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Sample records for enhanced pharmacological properties

  1. Biological and Pharmacological properties

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. Biological and Pharmacological properties. NOEA inhibits Ceramidase. Anandamide inhibits gap junction conductance and reduces sperm fertilizing capacity. Endogenous ligands for Cannabinoid receptors (anandamide and NPEA). Antibacterial and antiviral ...

  2. PHARMACOLOGICAL PROPERTIES OF SECURIDACA ...

    African Journals Online (AJOL)

    Methanolic Extract of the root-bark of Securidaca longipedunculata was tested for pharmacological activity on isolated vascular and extra-vascular smooth muscle preparations. The root barks extract (50-800mg/ml) inhibited and/or abolished, in a concentration-dependent manner, the myogenic, spontaneous contractions ...

  3. Non Pharmacological Cognitive Enhancers – Current Perspectives

    OpenAIRE

    SACHDEVA, Ankur; Kumar, Kuldip; Anand, Kuljeet Singh

    2015-01-01

    Cognition refers to the mental processes involved in thinking, knowing, remembering, judging, and problem solving. Cognitive dysfunctions are an integral part of neuropsychiatric disorders as well as in healthy ageing. Cognitive Enhancers are molecules that help improve aspects of cognition like memory, intelligence, motivation, attention and concentration. Recently, Non Pharmacological Cognitive Enhancers have gained popularity as effective and safe alternative to various established drugs. ...

  4. Non Pharmacological Cognitive Enhancers - Current Perspectives.

    Science.gov (United States)

    Sachdeva, Ankur; Kumar, Kuldip; Anand, Kuljeet Singh

    2015-07-01

    Cognition refers to the mental processes involved in thinking, knowing, remembering, judging, and problem solving. Cognitive dysfunctions are an integral part of neuropsychiatric disorders as well as in healthy ageing. Cognitive Enhancers are molecules that help improve aspects of cognition like memory, intelligence, motivation, attention and concentration. Recently, Non Pharmacological Cognitive Enhancers have gained popularity as effective and safe alternative to various established drugs. Many of these Non Pharmacological Cognitive Enhancers seem to be more efficacious compared to currently available Pharmacological Cognitive Enhancers. This review describes and summarizes evidence on various Non Pharmacological Cognitive Enhancers such as physical exercise, sleep, meditation and yoga, spirituality, nutrients, computer training, brain stimulation, and music. We also discuss their role in ageing and different neuro-psychiatric disorders, and current status of Cochrane database recommendations. We searched the Pubmed database for the articles and reviews having the terms 'non pharmacological and cognitive' in the title, published from 2000 till 2014. A total of 11 results displayed, out of which 10 were relevant to the review. These were selected and reviewed. Appropriate cross-references within the articles along with Cochrane reviews were also considered and studied.

  5. Pharmacological and clinical properties of curcumin

    Directory of Open Access Journals (Sweden)

    Huang S

    2011-06-01

    Full Text Available Christopher S Beevers¹, Shile Huang²¹Department of Pharmacology, Ross University School of Medicine, Picard-Portsmouth, Commonwealth of Dominica; ²Department of Biochemistry and Molecular Biology, Louisiana State University Health Sciences Center, Shreveport, LA, USAAbstract: The polyphenol natural product curcumin has been the subject of numerous studies over the past decades, which have identified and characterized the compound's pharmacokinetic, pharmacodynamic, and clinical pharmacological properties. In in vitro and in vivo model systems, curcumin displays potent pharmacological effects, by targeting many critical cellular factors, through a diverse array of mechanisms of action. Despite this tremendous molecular versatility, however, the clinical application of curcumin remains limited due to poor pharmacokinetic characteristics in human beings. The current trend is to develop and utilize unique delivery systems, chemical derivatives, and chemical analogs to circumvent these pharmacological obstacles, in order to optimize the conditions for curcumin as a chemopreventive and chemotherapeutic agent in diseases such as cancer, diabetes, obesity, Alzheimer's disease, and inflammatory disorders. The present work seeks to review recent studies in the basic pharmacological principles and potential clinical applications of curcumin.Keywords: curcumin, pharmacological properties, signal transduction, cellular targets, cancer, inflammation

  6. Pharmacological enhancement of treatment for amblyopia

    Directory of Open Access Journals (Sweden)

    Rashad MA

    2012-03-01

    Full Text Available Mohammad A RashadOphthalmology Department, Faculty of Medicine, Ain Shams University, Cairo, EgyptBackground: The purpose of this study was to compare a weight-adjusted dose of carbidopa-levodopa as treatment adjunctive to occlusion therapy with occlusion therapy alone in children and adults with different types of amblyopia.Methods: This prospective study included 63 patients with amblyopia classified into two groups, ie, an occlusion group which included 35 patients who received occlusion therapy only and a pharmacological enhancement group which included 28 patients who received oral carbidopa-levodopa together with occlusion therapy for 6 weeks.Results: The mean logarithm of the minimal angle of resolution (logMAR of the eyes with amblyopia was not significantly different in the occlusion group (0.52, 0.52, and 0.51 than in the pharmacological enhancement group (0.58, 0.49, and 0.56 at three follow-up visits (at months 1, 3, and 12, respectively. There was a highly significant improvement in mean logMAR of amblyopic eyes compared with baseline in both occlusion groups (from 0.68 to 0.52, from 0.68 to 0.52, and from 0.68 to 0.51 and in the pharmacological enhancement group (from 0.81 to 0.58, from 0.81 to 0.49, and from 0.81 to 0.56 at the month 1, 3, and 12 visits (P = 0.01, P = 0.01, and P = 0.001, respectively. The improvement of mean logMAR in the subgroup of patients older than 12 years was greater in the pharmacological enhancement group (42.5% than in the occlusion group (30%. The improvement of mean logMAR in the subgroup of patients with severe amblyopia was greater in the pharmacological enhancement group (34.3% than in the occlusion group (22%.Conclusion: Significant improvement was reported in both groups at all follow-up visits over 1 year. Regardless of the etiology of amblyopia, levodopa-carbidopa may be added to part-time occlusion in older patients as a means of increasing the plasticity of the visual cortex. Levodopa may add

  7. Therapeutic potentials and pharmacological properties of Moringa ...

    African Journals Online (AJOL)

    Therapeutic potentials and pharmacological properties of Moringa oleifera Lam in the treatment of diabetes mellitus and related complications. ... DM is a metabolic disorder resulting from abnormal insulin secretion. This leads to chronic hyperglycemia with disturbances of carbohydrate metabolism. Hyperglycemic-induced ...

  8. Ethnobotanical, phytochemical and pharmacological properties of ...

    African Journals Online (AJOL)

    Ethnobotanical, phytochemical and pharmacological ... Abstract. Purpose: To present an overview of the ethnobotany, phytochemistry and pharmacology of Crinum ..... PhD thesis. University of the Witwatersrand;. 2007. 8. Moeng TE. An investigation into the trade of medicinal plants by muthi shops and street vendors in the.

  9. Pharmacological Enhancement of Memory and Executive Functioning in Laboratory Animals

    OpenAIRE

    Floresco, Stan B.; Jentsch, James D

    2010-01-01

    Investigating how different pharmacological compounds may enhance learning, memory, and higher-order cognitive functions in laboratory animals is the first critical step toward the development of cognitive enhancers that may be used to ameliorate impairments in these functions in patients suffering from neuropsychiatric disorders. Rather than focus on one aspect of cognition, or class of drug, in this review we provide a broad overview of how distinct classes of pharmacological compounds may ...

  10. Phytochemistry and pharmacologic properties of Myristica fragrans ...

    African Journals Online (AJOL)

    Myristica fragrans is known as “nutmeg”, its extracts and essential oil are important in drug development with numerous pharmacological activities in South Africa, India and other tropical countries. For a long time, M. fragrans has been used in traditional medicines as a carminative, stimulant, narcotic, emmenagogue and ...

  11. Ethnobotanical, phytochemical and pharmacological properties of ...

    African Journals Online (AJOL)

    Purpose: To present an overview of the ethnobotany, phytochemistry and pharmacology of Crinum bulbispermum so as to understand its importance and potential in primary healthcare systems. Methods: A review of the literature was undertaken and an in-depth analysis of previous research on ethnobotany, phytochemistry ...

  12. Pharmacological properties of cashew ( Anacardium occidentale ...

    African Journals Online (AJOL)

    Net of cashew nut shell is classified according to the method of production of: (1) net of the shell of natural cashew nut (60-65% anacardic acid; 15-20% cardol and 10% of cardanol) and (2) liquid from the technical cashew nut shell ... Keywords: Cashew liquid, cosmetics, pharmacological, pharmaceutical, preparation ...

  13. Pharmacological Properties of Capparis spinosa Linn

    OpenAIRE

    Moufid A; Farid O; Eddouks, M

    2015-01-01

    Capparis spinosa Linn. (Capparaceae) was traditionally used for pharmacological purposes and has potential for use in modern cosmetics. This review aims to assess the current available knowledge of Capparis spinosa and its constituents for management of several diseases. Bibliographic investigation was carried out by scrutinizing classical text books and peer reviewed papers, consulting worldwide accepted scientific databases (SCOPUS, PUBMED, SCIENCE DIRECT, Google Scholar...

  14. Attitudes toward pharmacological cognitive enhancement-a review

    NARCIS (Netherlands)

    Schelle, K.J.; Faulmüller, N.S.; Caviola, L.; Hewstone, M.

    2014-01-01

    A primary means for the augmentation of cognitive brain functions is "pharmacological cognitive enhancement" (PCE). The term usually refers to the off-label use of medical substances to improve mental performance in healthy individuals. With the final aim to advance the normative debate taking place

  15. Physician attitudes towards pharmacological cognitive enhancement: safety concerns are paramount.

    Directory of Open Access Journals (Sweden)

    Opeyemi C Banjo

    2010-12-01

    Full Text Available The ethical dimensions of pharmacological cognitive enhancement have been widely discussed in academic circles and the popular media, but missing from the conversation have been the perspectives of physicians - key decision makers in the adoption of new technologies into medical practice. We queried primary care physicians in major urban centers in Canada and the United States with the aim of understanding their attitudes towards cognitive enhancement. Our primary hypothesis was that physicians would be more comfortable prescribing cognitive enhancers to older patients than to young adults. Physicians were presented with a hypothetical pharmaceutical cognitive enhancer that had been approved by the regulatory authorities for use in healthy adults, and was characterized as being safe, effective, and without significant adverse side effects. Respondents overwhelmingly reported increasing comfort with prescribing cognitive enhancers as the patient age increased from 25 to 65. When asked about their comfort with prescribing extant drugs that might be considered enhancements (sildenafil, modafinil, and methylphenidate or our hypothetical cognitive enhancer to a normal, healthy 40 year old, physicians were more comfortable prescribing sildenafil than any of the other three agents. When queried as to the reasons they answered as they did, the most prominent concerns physicians expressed were issues of safety that were not offset by the benefit afforded the individual, even in the face of explicit safety claims. Moreover, many physicians indicated that they viewed safety claims with considerable skepticism. It has become routine for safety to be raised and summarily dismissed as an issue in the debate over pharmacological cognitive enhancement; the observation that physicians were so skeptical in the face of explicit safety claims suggests that such a conclusion may be premature. Thus, physician attitudes suggest that greater weight be placed upon the

  16. Swiss University Students' Attitudes toward Pharmacological Cognitive Enhancement.

    Science.gov (United States)

    Maier, Larissa J; Liakoni, Evangelia; Schildmann, Jan; Schaub, Michael P; Liechti, Matthias E

    2015-01-01

    Pharmacological cognitive enhancement (PCE) refers to the nonmedical use of prescription or recreational drugs to enhance cognitive performance. Several concerns about PCE have been raised in the public. The aim of the present study was to investigate students' attitudes toward PCE. Students at three Swiss universities were invited by e-mail to participate in a web-based survey. Of the 29,282 students who were contacted, 3,056 participated. Of these students, 22% indicated that they had used prescription drugs (12%) or recreational substances including alcohol (14%) at least once for PCE. The use of prescription drugs or recreational substances including alcohol prior to the last exam was reported by 16%. Users of pharmacological cognitive enhancers were more likely to consider PCE fair (24%) compared with nonusers (11%). Only a minority of the participants agreed with the nonmedical use of prescription drugs by fellow students when assuming weak (7%) or hypothetically strong efficacy and availability to everyone (14%). Two-thirds (68%) considered performance that is obtained with PCE less worthy of recognition. Additionally, 80% disagreed that PCE is acceptable in a competitive environment. More than half (64%) agreed that PCE in academia is similar to doping in sports. Nearly half (48%) claimed that unregulated access to pharmacological cognitive enhancers increases the pressure to engage in PCE and educational inequality (55%). In conclusion, Swiss students' main concerns regarding PCE were related to coercion and fairness. As expected, these concerns were more prevalent among nonusers than among users of pharmacological cognitive enhancers. More balanced information on PCE should be shared with students, and future monitoring of PCE is recommended.

  17. [Pharmacological properties od steroid glycosides from Ruscus ponticus].

    Science.gov (United States)

    Abuladze, G V; Mulkidzhanian, K G; Novikova, Zh N

    2002-01-01

    Some pharmacological properties of the sum of steroidal glycosides (ruscoponin preparation) extracted from underground parts of Ruscus ponticus were studied. The drug exhibits a pronounced antiexudative effect (related to the alpha 1-adrenergic activity) on the models of formalin edema and pouch granuloma in rats and a thermal rectum inflammation in mice. The drug exhibited no hepato-, nephro-, and gastrotoxicity.

  18. Pharmacological enhancement of memory and executive functioning in laboratory animals.

    Science.gov (United States)

    Floresco, Stan B; Jentsch, James D

    2011-01-01

    Investigating how different pharmacological compounds may enhance learning, memory, and higher-order cognitive functions in laboratory animals is the first critical step toward the development of cognitive enhancers that may be used to ameliorate impairments in these functions in patients suffering from neuropsychiatric disorders. Rather than focus on one aspect of cognition, or class of drug, in this review we provide a broad overview of how distinct classes of pharmacological compounds may enhance different types of memory and executive functioning, particularly those mediated by the prefrontal cortex. These include recognition memory, attention, working memory, and different components of behavioral flexibility. A key emphasis is placed on comparing and contrasting the effects of certain drugs on different cognitive and mnemonic functions, highlighting methodological issues associated with this type of research, tasks used to investigate these functions, and avenues for future research. Viewed collectively, studies of the neuropharmacological basis of cognition in rodents and non-human primates have identified targets that will hopefully open new avenues for the treatment of cognitive disabilities in persons affected by mental disorders.

  19. Xanthones from mangosteen (Garcinia mangostana): multi-targeting pharmacological properties.

    Science.gov (United States)

    Jindarat, Sarawut

    2014-02-01

    This review focuses on mangosteen pericarp extracts, xanthones and derivatives for the future laboratory experiment and development in pharmacological aspects. All relevant literature databases were searched up to 2 March 2014. The search terms included mangosteen, xanthone, mangostin, and gatanin in all of the human, animal, in vitro and in vivo studies. Anti-intflammation, antioxidant, antibacterial, anticancer and antiulcer properties of each substance were the key parameters. Xanthones are a group of oxygen-containing heterocyclic compounds including alpha-mangostin, gamma-mangostin, mangosteen extract, xanthone derivatives and synthetic xanthones, which provide remarkable and diverse pharmacological effects such as anticancer, antioxidant, anti-inflammatory and antimicrobial activities. These xanthone compounds may play a major role in therapeutic treatment ofthe diseases but precise mechanisms ofaction are still unclear and needfurther investigation.

  20. The Genus Spilanthes Ethnopharmacology, Phytochemistry, and Pharmacological Properties: A Review

    Directory of Open Access Journals (Sweden)

    Jayaraj Paulraj

    2013-01-01

    Full Text Available Spilanthes spp. are popular, over-the-counter remedies; they are sold over the internet under various names and are widely used in traditional medicine in various cultures. This review will summarize the important reports on the ethnopharmacology, botany, phytochemistry, and pharmacological properties as described in the literature from recent years (1920 to 2013. Spilanthes spp. are used for more than 60 types of disorders. They are reported to contain a number of biologically active phytochemicals, although a large number of ethnopharmacological uses have been documented; only a few of these species have been investigated for their chemical and biological activities. The studies are carried out mainly on Spilanthes extracts and a few metabolites substantiate the uses of these plants in traditional medicine. Well-conducted pharmacological studies are still needed for several traditional indications, and the mechanisms of action by which the plant extracts and the active compounds exert their pharmacological effects remain to be studied. They are predominantly used as extracts in personal care products, traditional medicines, and the pharmaceutical and culinary areas. Suggestions are made regarding some of the possible mechanisms of action as to how the known compounds may exert their biological activity.

  1. On the pharmacological properties of Delta9-tetrahydrocannabinol (THC).

    Science.gov (United States)

    Costa, Barbara

    2007-08-01

    Cannabis is one of the first plants used as medicine, and the notion that it has potentially valuable therapeutic properties is a matter of current debate. The isolation of its main constituent, Delta9-tetrahydrocannabinol (THC), and the discovery of the endocannabinoid system (cannabinoid receptors CB1 and CB2 and their endogenous ligands) made possible studies concerning the pharmacological activity of cannabinoids. This paper reviews some of the most-important findings in the field of THC pharmacology. Clinical trials, anecdotal reports, and experiments employing animal models strongly support the idea that THC and its derivatives exhibit a wide variety of therapeutic applications. However, the psychotropic effects observed in laboratory animals and the adverse reactions reported during human trials, as well as the risk of tolerance development and potential dependence, limit the application of THC in therapy. Nowadays, researchers focus on other therapeutic strategies by which the endocannabinoid system might be modulated to clinical advantage (inhibitor or activator of endocannabinoid biosynthesis, cellular uptake, or metabolism). However, emerging evidence highlights the beneficial effects of the whole cannabis extract over those observed with single components, indicating cannabis-based medicines as new perspective to revisit the pharmacology of this plant.

  2. Neuroethical issues in pharmacological cognitive enhancement.

    Science.gov (United States)

    Mohamed, Ahmed Dahir

    2014-09-01

    Neuroethics is an emerging field that in general deals with the ethics of neuroscience and the neuroscience of ethics. In particular, it is concerned with the ethical issues in the translation of neuroscience to clinical practice and in the public domain. Numerous ethical issues arise when healthy individuals use pharmacological substances known as pharmacological cognitive enhancers (PCEs) for non-medical purposes in order to boost higher-order cognitive processes such as memory, attention, and executive functions. However, information regarding their actual use, benefits, and harms to healthy individuals is currently lacking. Neuroethical issues that arise from their use include the unknown side effects that are associated with these drugs, concerns about the modification of authenticity and personhood, and as a result of inequality of access to these drugs, the lack of distributive justice and competitive fairness that they may cause in society. Healthy individuals might be coerced by social institutions that force them to take these drugs to function better. These drugs might enable or hinder healthy individuals to gain better moral and self-understanding and autonomy. However, how these drugs might achieve this still remains speculative and unknown. Hence, before concrete policy decisions are made, the cognitive effects of these drugs should be determined. The initiation of accurate surveys to determine the actual usage of these drugs by healthy individuals from different sections of the society is proposed. In addition, robust empirical research need to be conducted to delineate not only whether or not these drugs modify complex higher-order cognitive processes but also how they might alter important human virtues such as empathy, moral reasoning, creativity, and motivation in healthy individuals. WIREs Cogn Sci 2014, 5:533-549. doi: 10.1002/wcs.1306 For further resources related to this article, please visit the WIREs website. The author has declared no

  3. Cornus mas: a review on traditional uses and pharmacological properties.

    Science.gov (United States)

    Hosseinpour-Jaghdani, Fatemeh; Shomali, Tahoora; Gholipour-Shahraki, Sajedeh; Rahimi-Madiseh, Mohammad; Rafieian-Kopaei, Mahmoud

    2017-03-31

    Medicinal plants that are used today have been known by people of ancient cultures around the world and have largely been considered due to their medicinal properties. Cornus mas L. (Cornelian cherry) is one of these medicinal plants with high level of antioxidant activity. Cornelian cherry is an attractive ornamental plant with delicious fruit having nutritional and therapeutic values. The main purpose of this paper is to present and summarize the pharmacological and therapeutic effects from researches done on Cornelian cherry in studies from 2000 to 2016. Information and findings in this review were taken from electronic journals in some websites including PubMed, Elsevier, ISI, Google scholar, SID and relevant books. C. mas L. is important in terms of decoration and is used in traditional medicine to treat diarrhea, inflammatory bowel disease, cholera, fever, malaria, kidney stones, urinary tract infections, cancer, bleeding and heat stroke. Several studies have shown that Cornelian cherry fruit plays an important role in prevention of atherosclerosis, blood sugar, lipid profiles and reduction of fat accumulation in the liver. Cornelian cherry has antimicrobial, antiparasitic, anti-inflammatory, antioxidant and anticancer effects as well as protecting liver, kidney and cardiovascular system. Using Cornelian cherry in pharmaceutical and food industries has caused fantastic value of this plant. Pharmaceutical properties of Cornelian cherry seeds, fruits, leaves and stems have led the need of further studies to explore the other unknown effects or review mechanism of its pharmacological effects for preparation of new drugs.

  4. [Molecule of taurine and its quantum-pharmacological properties].

    Science.gov (United States)

    Zahorodnyĭ, M I; Nebesna, T Iu

    2007-01-01

    Quantum-pharmacological properties of taurine and its zwitterion form have been studied. Geometrical and energetic parameters were calculated using ab initio 6-31G* technique. These parameters are the following: distance between atoms, distribution of electronic density only of external valency electrons, distribution of electrostatic potential, atomic charges, dipole moment, localization and energy of high and low occupied and low unoccupied molecular orbitals. Authors established that the sulfonate group is a electrophilic center of taurin molecul and amide group is a nucleophilic center. The biggest value of electrostatic potential is located around sulfonate group. The big value of energy of low occupied molecular orbital of taurin gives grounds to consider this substance as a reducing reagent and explains its antioxidant properties.

  5. Pills or push-ups? Effectiveness and public perception of pharmacological and non-pharmacological cognitive enhancement

    Directory of Open Access Journals (Sweden)

    Lucius eCaviola

    2015-12-01

    Full Text Available We review work on the effectiveness of different forms of cognitive enhancement, both pharmacological and non-pharmacological. We consider caffeine, methylphenidate, and modafinil for pharmacological cognitive enhancement (PCE and computer training, physical exercise, and sleep for non-pharmacological cognitive enhancement (NPCE. We find that all of the techniques described can produce significant beneficial effects on cognitive performance. However, effect sizes are moderate, and consistently dependent on individual and situational factors as well as the cognitive domain in question. Although meta-analyses allowing a quantitative comparison of effectiveness across techniques are lacking to date, we can conclude that PCE is not more effective than NPCE. We discuss the physiological reasons for this limited effectiveness.We then propose that even though their actual effectiveness seems similar, in the general public PCE is perceived as fundamentally different from NPCE, in terms of effectiveness, but also in terms of acceptability. We illustrate the potential consequences such a misperception of PCE can have.

  6. Pharmacological Properties and Molecular Mechanisms of Thymol: Prospects for Its Therapeutic Potential and Pharmaceutical Development

    Science.gov (United States)

    Nagoor Meeran, Mohamed Fizur; Javed, Hayate; Al Taee, Hasan; Azimullah, Sheikh; Ojha, Shreesh K.

    2017-01-01

    Thymol, chemically known as 2-isopropyl-5-methylphenol is a colorless crystalline monoterpene phenol. It is one of the most important dietary constituents in thyme species. For centuries, it has been used in traditional medicine and has been shown to possess various pharmacological properties including antioxidant, free radical scavenging, anti-inflammatory, analgesic, antispasmodic, antibacterial, antifungal, antiseptic and antitumor activities. The present article presents a detailed review of the scientific literature which reveals the pharmacological properties of thymol and its multiple therapeutic actions against various cardiovascular, neurological, rheumatological, gastrointestinal, metabolic and malignant diseases at both biochemical and molecular levels. The noteworthy effects of thymol are largely attributed to its anti-inflammatory (via inhibiting recruitment of cytokines and chemokines), antioxidant (via scavenging of free radicals, enhancing the endogenous enzymatic and non-enzymatic antioxidants and chelation of metal ions), antihyperlipidemic (via increasing the levels of high density lipoprotein cholesterol and decreasing the levels of low density lipoprotein cholesterol and low density lipoprotein cholesterol in the circulation and membrane stabilization) (via maintaining ionic homeostasis) effects. This review presents an overview of the current in vitro and in vivo data supporting thymol’s therapeutic activity and the challenges concerning its use for prevention and its therapeutic value as a dietary supplement or as a pharmacological agent or as an adjuvant along with current therapeutic agents for the treatment of various diseases. It is one of the potential candidates of natural origin that has shown promising therapeutic potential, pharmacological properties and molecular mechanisms as well as pharmacokinetic properties for the pharmaceutical development of thymol. PMID:28694777

  7. Review: Diverse pharmacological properties of Cinnamomum cassia: A review.

    Science.gov (United States)

    Zaidi, Syed Faisal; Aziz, Muhammad; Muhammad, Jibran Sualeh; Kadowaki, Makoto

    2015-07-01

    Cinnamomum cassia is widely utilized as a spice in different cookeries worldwide, especially in Asian cuisines. This herb is also being used in different forms of traditional medicine (Unani, Ayurvedic, Japanese and Chinese) for managing conditions like dyspepsia, peptic ulcer disease and ischemic brain injury. Recent studies have shown the scientific evidence for the medicinal use of this particular herb in several diseases like H. pylori infection, diabetes, brain ischemia and cancers. This article reviews the literature on potential benefits of the herb published within the last 10 years. The authors used Medical Subject Headings (MeSH) terms "Cinnamomum" with "cassia" or "arromaticum" to filter the PubMed database. To date, no systemic review focusing on medicinal use of C. cassia was found in the literature. Various research articles elucidating diverse pharmacological properties of C. cassia were identified. The standardised extract of C. cassia or the active compounds extracted from the herb might prove to be a novel candidate for early prevention and complimentary management of conditions like diabetes mellitus or H. pylori-associated disorders.

  8. A Review on Pharmacological Properties of Zingerone (4-(4-Hydroxy-3-methoxyphenyl-2-butanone

    Directory of Open Access Journals (Sweden)

    Bilal Ahmad

    2015-01-01

    Full Text Available Humans have been using natural products for medicinal use for ages. Natural products of therapeutic importance are compounds derived from plants, animals, or any microorganism. Ginger is also one of the most commonly used condiments and a natural drug in vogue. It is a traditional medicine, having some active ingredients used for the treatment of numerous diseases. During recent research on ginger, various ingredients like zingerone, shogaol, and paradol have been obtained from it. Zingerone (4-(4-hydroxy-3-methoxyphenyl-2-butanone is a nontoxic and inexpensive compound with varied pharmacological activities. It is the least pungent component of Zingiber officinale. Zingerone is absent in fresh ginger but cooking or heating transforms gingerol to zingerone. Zingerone closely related to vanillin from vanilla and eugenol from clove. Zingerone has potent anti-inflammatory, antidiabetic, antilipolytic, antidiarrhoeic, antispasmodic, and so forth properties. Besides, it displays the property of enhancing growth and immune stimulation. It behaves as appetite stimulant, anxiolytic, antithrombotic, radiation protective, and antimicrobial. Also, it inhibits the reactive nitrogen species which are important in causing Alzheimer’s disease and many other disorders. This review is written to shed light on the various pharmacological properties of zingerone and its role in alleviating numerous human and animal diseases.

  9. Marine Bioactives: Pharmacological Properties and Potential Applications against Inflammatory Diseases

    Directory of Open Access Journals (Sweden)

    Graziano Riccioni

    2012-04-01

    Full Text Available Inflammation is a hot topic in medical research, because it plays a key role in inflammatory diseases: rheumatoid arthritis (RA and other forms of arthritis, diabetes, heart diseases, irritable bowel syndrome, Alzheimer’s disease, Parkinson’s disease, allergies, asthma, even cancer and many others. Over the past few decades, it was realized that the process of inflammation is virtually the same in different disorders, and a better understanding of inflammation may lead to better treatments for numerous diseases. Inflammation is the activation of the immune system in response to infection, irritation, or injury, with an influx of white blood cells, redness, heat, swelling, pain, and dysfunction of the organs involved. Although the pathophysiological basis of these conditions is not yet fully understood, reactive oxygen species (ROS have often been implicated in their pathogenesis. In fact, in inflammatory diseases the antioxidant defense system is compromised, as evidenced by increased markers of oxidative stress, and decreased levels of protective antioxidant enzymes in patients with rheumatoid arthritis (RA. An enriched diet containing antioxidants, such as vitamin E, vitamin C, β-carotene and phenolic substances, has been suggested to improve symptoms by reducing disease-related oxidative stress. In this respect, the marine world represents a largely untapped reserve of bioactive ingredients, and considerable potential exists for exploitation of these bioactives as functional food ingredients. Substances such as n-3 oils, carotenoids, vitamins, minerals and peptides provide a myriad of health benefits, including reduction of cardiovascular diseases, anticarcinogenic and anti-inflammatory activities. New marine bioactives are recently gaining attention, since they could be helpful in combating chronic inflammatory degenerative conditions. The aim of this review is to examine the published studies concerning the potential pharmacological

  10. Pharmacological properties of Salvia officinalis and its components.

    Science.gov (United States)

    Ghorbani, Ahmad; Esmaeilizadeh, Mahdi

    2017-10-01

    Salvia officinalis (Sage) is a plant in the family of Labiatae/Lamiaceae. It is native to Middle East and Mediterranean areas, but today has been naturalized throughout the world. In folk medicine, S. officinalis has been used for the treatment of different kinds of disorders including seizure, ulcers, gout, rheumatism, inflammation, dizziness, tremor, paralysis, diarrhea, and hyperglycemia. In recent years, this plant has been a subject of intensive studies to document its traditional use and to find new biological effects. These studies have revealed a wide range of pharmacological activities for S. officinalis. Present review highlights the up-to-date information on the pharmacological findings that have been frequently reported for S. officinalis. These findings include anticancer, anti-inflammatory, antinociceptive, antioxidant, antimicrobial, antimutagenic, antidementia, hypoglycemic, and hypolipidemic effects. Also, chemical constituents responsible for pharmacological effects of S. officinalis and the clinical studies on this plant are presented and discussed.

  11. Pharmacological properties of Salvia officinalis and its components

    Directory of Open Access Journals (Sweden)

    Ahmad Ghorbani

    2017-10-01

    Full Text Available Salvia officinalis (Sage is a plant in the family of Labiatae/Lamiaceae. It is native to Middle East and Mediterranean areas, but today has been naturalized throughout the world. In folk medicine, S. officinalis has been used for the treatment of different kinds of disorders including seizure, ulcers, gout, rheumatism, inflammation, dizziness, tremor, paralysis, diarrhea, and hyperglycemia. In recent years, this plant has been a subject of intensive studies to document its traditional use and to find new biological effects. These studies have revealed a wide range of pharmacological activities for S. officinalis. Present review highlights the up-to-date information on the pharmacological findings that have been frequently reported for S. officinalis. These findings include anticancer, anti-inflammatory, antinociceptive, antioxidant, antimicrobial, antimutagenic, antidementia, hypoglycemic, and hypolipidemic effects. Also, chemical constituents responsible for pharmacological effects of S. officinalis and the clinical studies on this plant are presented and discussed.

  12. [Pharmacological properties of vortioxetine and its pre-clinical consequences].

    Science.gov (United States)

    David, D J; Tritschler, L; Guilloux, J-P; Gardier, A M; Sanchez, C; Gaillard, R

    2016-02-01

    Selective Serotonin Reuptake Inhibitors (SSRIs) are extensively used for the treatment of major depressive disorder (MDD). SSRIs are defined as indirect receptor agonists since the activation of postsynaptic receptors is a consequence of an increase in extracellular concentrations of serotonin (5-HT) mediated by the blockade of serotonin transporter. The activation of some serotoninergic receptors (5-HT1A, post-synaptic, 5-HT1B post-synaptic, 5-HT2B, and 5-HT4), but not all (5-HT1A, pre-synaptic, 5-HT1B pre-synaptic, 5-HT2A, 5-HT2C, 5-HT3, and probably 5-HT6), induces anxiolytic/antidepressive - like effects. Targetting specifically some of them could potentially improve the onset of action and/or efficacy and/or prevent MD relapse. Vortioxetine (Brintellix, 1- [2-(2,4-dimethylphenyl-sulfanyl)-phenyl]-piperazine) is a novel multi-target antidepressant drug approved by the Food and Drug Administration (FDA) and by European Medicines Agency. Its properties are markedly different from the extensively prescribed SSRIs. Compared to the SSRIs, vortioxetine is defined as a multimodal antidepressant drug since it is not only a serotonin reuptake inhibitor, but also a 5-HT1D, 5-HT3, 5-HT7 receptor antagonist, 5-HT1B receptor partial agonist and 5-HT1A receptor agonist. This specific pharmacological profile enables vortioxetine to affect not only the serotoninergic and noradrenergic systems, but also the histaminergic, cholinergic, gamma-butyric acid (GABA) ergic and glutamatergic ones. Thus, vortioxetine not only induces antidepressant-like or anxiolytic-like activity but also improves cognitive parameters in several animal models. Indeed, vortioxetine was shown to improve working memory, episodic memory, cognitive flexibility and spatial memory in young adult rodents and also in old animal models. These specific effects of the vortioxetine are of interest considering that cognitive dysfunction is a common comorbidity to MDD. Altogether, even though this molecule still

  13. Impact of Simulation-Enhanced Pharmacology Education in Prelicensure Nursing Education.

    Science.gov (United States)

    Sanko, Jill Steiner; Mckay, Mary

    Student and novice nurses are susceptible to committing medication errors related to lack of experience. To address medication safety, a quasi-experimental design (N = 120) was used to test the effect of adding simulation to an undergraduate nursing pharmacology course on students' confidence and competence, medication adverse events, and observed medication administration practices. Students who received simulation-enhanced pharmacology demonstrated important improvements in medication administration safety. Implementing simulation in nursing pharmacology curriculum is consistent with recommendations to implement Quality and Safety Education for Nurses competencies into nursing education.

  14. Angiotensin-(1-7) : Pharmacological properties and pharmacotherapeutic perspectives

    NARCIS (Netherlands)

    Iusuf, Dilek; Henning, Robert H.; van Gilst, Wiek H.; Roks, Anton J. M.

    2008-01-01

    Therapeutic modulation of the renin-angiotensin system is not complete without taking into consideration the beneficial effects of angiotensin-(1-7) in cardiovascular pathology. Various pharmacological pathways are already exploited to involve this heptapeptide in therapy as both inhibitors of

  15. A review on phytochemical and pharmacological properties of Litsea coreana.

    Science.gov (United States)

    Jia, Xuejing; Li, Peng; Wan, Jianbo; He, Chengwei

    2017-12-01

    Litsea coreana H. Lév. (Lauraceae) is used as an ethnic herb or beverage in China. Substantial studies indicate that it contains a variety of compounds and shows diverse bioactivities with no toxicity. This review analyzes and summarizes the ethnopharmacological applications, phytochemistry, and pharmacological activities and molecular mechanisms of L. coreana. Related literature (from 1998 to 2016) was obtained and compiled via searching databases including Scopus, Web of Science, Google Scholar, CNKI and PubMed. Keywords (Litsea coreana, hawk tea, eagle tea and laoying cha) were used to select the articles. Studies indicate that L. coreana contains characteristic polysaccharides, polyphenols, essential oils, and numerious flavonoids, which exhibit remarkable bioactivities, such as hepatoprotection, hyperglycaemia, anti-inflammation, antioxidation and antibacterial, through multiple molecular mechanisms. This paper provides a systematic review on the phytochemicals and pharmacological activities of L. coreana which should be useful for further study and application of this medicinal herb.

  16. Pharmacological enhancement of exposure-based treatment in PTSD: a qualitative review

    Directory of Open Access Journals (Sweden)

    Rianne A. de Kleine

    2013-10-01

    Full Text Available There is a good amount of evidence that exposure therapy is an effective treatment for posttraumatic stress disorder (PTSD. Notwithstanding its efficacy, there is room for improvement, since a large proportion of patients does not benefit from treatment. Recently, an interesting new direction in the improvement of exposure therapy efficacy for PTSD emerged. Basic research found evidence of the pharmacological enhancement of the underlying learning and memory processes of exposure therapy. The current review aims to give an overview of clinical studies on pharmacological enhancement of exposure-based treatment for PTSD. The working mechanisms, efficacy studies in PTSD patients, and clinical utility of four different pharmacological enhancers will be discussed: D-cycloserine, MDMA, hydrocortisone, and propranolol.

  17. Attitudes towards pharmacological cognitive enhancement – a review

    Directory of Open Access Journals (Sweden)

    Kimberly Johanna Schelle

    2014-04-01

    Full Text Available A primary means for the augmentation of cognitive brain functions is ‘pharmacological cognitive enhancement’ (PCE. The term usually refers to the off-label use of medical substances to improve mental performance in healthy individuals. With the final aim to advance the normative debate taking place on that topic, several empirical studies have been conducted to assess the attitudes towards PCE of groups outside the normative academic debate. In this review, we provide an overview of the 40 empirical studies published so far, reporting both their methodology and results. Overall, we find that several concerns about the use of PCE are prevalent in the public. These concerns largely match those discussed in the normative academic debate. We present our findings structured amongst the three most common concerns: medical safety, coercion and fairness. Fairness is divided into three subthemes: equality of opportunity, honesty and authenticity. Attitudes regarding some concerns are more coherent across studies (e.g. coercion, whereas for others we find mixed results (e.g. authenticity. Moreover, we find differences in how specific groups—such as users, nonusers, students, parents, and health care providers—perceive PCE: a coherent finding is that nonusers display more concerns regarding medical safety and fairness than users. We discuss potential psychological explanations for these differences.

  18. The promise and peril of the pharmacological enhancer Modafinil.

    Science.gov (United States)

    Tannenbaum, Julie

    2014-10-01

    The neuro-enhancement Modafinil promises to dramatically increase users' waking hours without much sacrifice to clarity of thought and without serious side effects (inducing addiction). For Modafinil to be advantageous, its usage must enable access to goods that themselves improve the quality of one's life. I draw attention to a variety of conditions that must be met for an experience, activity or object to improve the quality of one's life, such as positional, relational, and saturation conditions, as well as it's being good for its own sake. I discuss and describe the contexts in which widespread usage (legal or not) of Modafinil would undermine these conditions being met, and thus users would fail to significantly improve the quality of their lives and would in fact potentially make both themselves and nonusers worse off in important respects thus far overlooked by critics. In the right contexts, where free time is protected and prolonged, Modafinil does have a variety of potential benefits including, most interestingly, a distinctive form of agency possible only in free time. The potential disadvantages and advantages highlighted in this article are relevant not only to public institutions deciding whether to legalize Modafinil's use as an enhancement but also to individuals deciding whether to use it illegally, as well as to the questions of how and whether to alter key features of one's context (e.g. regulating work hours or extending social services) rather than, or in addition, to regulating the use of enhancement drugs such as Modafinil. © 2012 John Wiley & Sons Ltd.

  19. Osthole: A Review on Its Bioactivities, Pharmacological Properties, and Potential as Alternative Medicine

    Directory of Open Access Journals (Sweden)

    Zhong-Rong Zhang

    2015-01-01

    Full Text Available This paper reviews the latest understanding of biological and pharmacological properties of osthole (7-methoxy-8-(3-methyl-2-butenyl-2H-1-benzopyran-2-one, a natural product found in several medicinal plants such as Cnidium monnieri and Angelica pubescens. In vitro and in vivo experimental results have revealed that osthole demonstrates multiple pharmacological actions including neuroprotective, osteogenic, immunomodulatory, anticancer, hepatoprotective, cardiovascular protective, and antimicrobial activities. In addition, pharmacokinetic studies showed osthole uptake and utilization are fast and efficient in body. Moreover, the mechanisms of multiple pharmacological activities of osthole are very likely related to the modulatory effect on cyclic adenosine monophosphate (cAMP and cyclic adenosine monophosphate (cGMP level, though some mechanisms remain unclear. This review aims to summarize the pharmacological properties of osthole and give an overview of the underlying mechanisms, which showcase its potential as a multitarget alternative medicine.

  20. Osthole: A Review on Its Bioactivities, Pharmacological Properties, and Potential as Alternative Medicine

    Science.gov (United States)

    Zhang, Zhong-Rong; Leung, Wing Nang; Cheung, Ho Yee; Chan, Chun Wai

    2015-01-01

    This paper reviews the latest understanding of biological and pharmacological properties of osthole (7-methoxy-8-(3-methyl-2-butenyl)-2H-1-benzopyran-2-one), a natural product found in several medicinal plants such as Cnidium monnieri and Angelica pubescens. In vitro and in vivo experimental results have revealed that osthole demonstrates multiple pharmacological actions including neuroprotective, osteogenic, immunomodulatory, anticancer, hepatoprotective, cardiovascular protective, and antimicrobial activities. In addition, pharmacokinetic studies showed osthole uptake and utilization are fast and efficient in body. Moreover, the mechanisms of multiple pharmacological activities of osthole are very likely related to the modulatory effect on cyclic adenosine monophosphate (cAMP) and cyclic adenosine monophosphate (cGMP) level, though some mechanisms remain unclear. This review aims to summarize the pharmacological properties of osthole and give an overview of the underlying mechanisms, which showcase its potential as a multitarget alternative medicine. PMID:26246843

  1. Metformin: a review of its pharmacological properties and therapeutic use.

    Science.gov (United States)

    Hermann, L S

    1979-09-01

    In a survey, the pharmacological and clinical documentation of metformin is presented and discussed, and the present state of knowledge relating to metformin-associated lactic acidosis is reviewed. The use of metformin in the treatment of diabetes is based on clinical experience over twenty years. It has been well documented that metformin is effective in maturity-onset diabetes both as monotherapy and in combination with a sulphonylurea. An advantage of metformin treatment is the tendency to weight reduction and the absence of significant hypoglycaemia; blood glucose levels are reduced only to normal. The disadvantages are the gastro-intestinal side effects and the potential risk of vitamin B 12 and folic acid deficiency during long-term use. Metformin-associated lactic acidosis is a very rare complication, which has mainly occured in patients with serious renal insufficiency or other contra-indications to the use of metformin. The association between phenformin and lactic acidosis has led to withdrawal of this biguanide in several countries. Metformin differs from phenformin in certain important respects, and the normal use of metformin does not involve the risk of side effects disproportionate to the intended effect. Further experimental studies are required to substantiate pharmacokinetics and metabolic effects of metformin in man.

  2. Phytochemistry, pharmacology and medicinal properties of Phyllanthus emblica Linn.

    Science.gov (United States)

    Gaire, Bhakta Prasad; Subedi, Lalita

    2014-12-09

    Phyllanthus emblica L. (syn. Emblica officinalis) is commonly known as Indian gooseberry. In Ayurveda, P. emblica has been extensively used, both as edible (tonic) plants and for its therapeutic potentials. P. emblica is highly nutritious and is reported as an important dietary source of vitamin C, minerals and amino acids. All parts of the plant are used for medicinal purposes, especially the fruit, which has been used in Ayurveda as a potent Rasayana (rejuvenator). P. emblica contains phytochemicals including fixed oils, phosphatides, essential oils, tannins, minerals, vitamins, amino acids, fatty acids, glycosides, etc. Various pharmaceutical potential of P. emblica has been reported previously including antimicrobial, antioxidant, anti-inflammatory, analgesic and antipyretic, adaptogenic, hepatoprotective, antitumor and antiulcerogenic activities either in combined formulation or P. emblica alone. The various other Ayurvedic potentials of P. emblica are yet to be proven scientifically in order to explore its broad spectrum of therapeutic effects. On this regards we, in this review, tried to explore the complete information of P. emblica including its pharmacognosy, phytochemistry and pharmacology.

  3. Pharmacological properties of Datura stramonium L. as a potential medicinal tree: an overview.

    Science.gov (United States)

    Soni, Priyanka; Siddiqui, Anees Ahmad; Dwivedi, Jaya; Soni, Vishal

    2012-12-01

    India has a great wealth of various naturally occurring plant drugs which have great potential pharmacological activities. Datura stramonium (D. stramonium) is one of the widely well known folklore medicinal herbs. The troublesome weed, D. stramonium is a plant with both poisonous and medicinal properties and has been proven to have great pharmacological potential with a great utility and usage in folklore medicine. D. stromonium has been scientifically proven to contain alkaloids, tannins, carbohydrates and proteins. This plant has contributed various pharmacological actions in the scientific field of Indian systems of medicines like analgesic and antiasthmatic activities. The present paper presents an exclusive review work on the ethnomedical, phytochemical, pharmacological activities of this plant.

  4. [Study on characteristics of pharmacological effects of traditional Chinese medicines distributing along stomach meridian based on medicinal property combination].

    Science.gov (United States)

    Zhang, Bai-Xia; Gu, Hao; Guo, Hong-Ling; Ma, Li; Wang, Yun; Qiao, Yan-Jiang

    2014-07-01

    At present, studies on traditional Chinese medicine (TCM) properties are mostly restricted to a single or two kinds of medicinal properties, but deviated from the holism of the theoretical system of TCMs. In this paper, the characteristics of pharmacological effects of different property combinations of TCMs distributing in the stomach meridian were take as the study objective. The data of properties of TCMs distributing in the stomach meridian was collected from the Pharmacopoeia of the People's Republic of China (2005). The data of pharmacological effects of TCMs distributing in the stomach meridian was collected from all of literatures recorded in Chinese Journal Full-text Database (CNKI) since 1980, Science of Chinese Materia Medica (Yan Zhenghua, People's Medical Publishing House, 2006) and Clinical Science of Chinese Materia Medica (Gao Xuemin, Zhong Gansheng, Hebei Science and Technology Publishing House, 2005). The corresponding pharmacological effects of property combinations of TCMs distributing in the stomach meridian was mined by the method of association rules. The results of the association rules were consistent with the empirical knowledge, and showed that different medicinal property combinations had respective pharmacological characteristics, including differences and similarities in pharmacological effects of different medicinal property combinations. Medicinal property combinations with identical four properties or five tastes showed similar pharmacological effects; whereas medicinal property combinations with different four properties or five tastes showed differentiated pharmacological effects. However, medicinal property combinations with different four properties or five tastes could also show similar pharmacological effects. In this study, the medicinal property theory and the pharmacological effects of TCMs were combined to reveal the main characteristics and regularity of pharmacological effects of TCMs distributing in the stomach meridian

  5. Moclobemide : An Update of its Pharmacological Properties and Therapeutic Use.

    Science.gov (United States)

    Fulton, Bret; Benfield, Paul

    1996-09-01

    phobia. Its lack of adverse anticholinergic, cardiovascular, cognitive and psychomotor effects makes moclobemide a particularly useful option in the elderly or patients with cardiac disease. The in vitro binding of moclobemide to monoamine oxidase (MAO)-A is weak but >167-fold more selective than for the MAO-B isozyme. However, its ex vivo activity against -A is more pronounced, perhaps indicating the existence of an as yet unidentified, more active metabolite. The ex vivo binding of moclobemide to MAO-A was demonstrated to be reversible, with recovery of enzyme activity within 16 hours. This is in contrast to older MAO inhibitors, which nonselectively and irreversibly bind to both MAO-A and MAO-B isozymes. The effects of moclobemide on monoamine metabolism and/or activity of monoaminergic neurons have been indirectly demonstrated in humans by reductions in plasma levels of the catecholamine metabolites homovanillic acid, 3,4-dihydroxyphenylacetic acid, 3-methoxy-4-hydroxyphenylglycol and the serotonin (5-hydroxytryptamine) metabolite 5-hydroxyindoleacetic acid. In vitro, moclobemide has no appreciable affinity for muscarinic, dopaminergic, seroto-nergic, adrenergic, H1-histaminergic, benzodiazepine or opioid receptors. In oral tyramine pressor tests moclobemide enhanced the hypertensive re-sponse to oral tyramine approximately 8- and 16-fold less than tranylcypromine and phenelzine, respectively. In addition, the pressor response induced by tyramine returned to baseline within 3 days of discontinuing moclobemide, whereas baseline sensitivity did not return until 4 and 8 weeks after discontinuing tranyl-cypromine and phenelzine, respectively. In contrast to other antidepressants, moclobemide has minimal effect on REM sleep and is reported to have no effect on, or to improve, sleep continuity in depressed patients. Unlike tricyclic antidepressants (TCAs), moclobemide has no reported effect on cognitive or psychomotor function. After single-dose oral administration

  6. Pharmacological promiscuity: dependence on compound properties and target specificity in a set of recent Roche compounds.

    Science.gov (United States)

    Peters, Jens-Uwe; Schnider, Patrick; Mattei, Patrizio; Kansy, Manfred

    2009-04-01

    The term "pharmacological promiscuity" describes a compound's pharmacological activity at multiple targets. Pharmacological promiscuity is undesired in typical drug discovery projects, which focus on the "one drug-one target" paradigm. Off-target activity can lead to adverse drug reactions, or can obscure pharmacodynamic effects in animal models. Therefore, advanced lead compounds, pharmacological tool compounds, and drug candidates are usually screened against panels of safety-relevant targets to detect unwanted pharmacological activities. To identify determinants of pharmacological promiscuity, we compared the panel screening outcomes of 213 recent Roche compounds with their molecular properties. Pronounced promiscuity was not observed below a threshold Clog P value of 2. For basic compounds, the propensity for weak off-target activity was found to increase with calculated basicities, whereas the potential for strong off-target activity depends more qualitatively on the presence of a positive charge at physiological pH. Compounds originating from projects with an aminergic receptor or transporter as a therapeutic target are particularly prone to promiscuity; the promiscuity of such compounds is mainly caused by their activity at other aminergic targets in the screening panel.

  7. [The glaucoma pharmacological treatment and biomechanical properties of the cornea].

    Science.gov (United States)

    Liehneová, I; Karlovská, S

    2014-10-01

    To evaluate and compare the impact of long-term use of intraocular pressure lowering medication on the biomechanical properties of the cornea. Group of 305 eyes of 154 patients newly diagnosed with primary open angle glaucoma (POAG, n = 68) or ocular hypertension (OH, n = 6) was enrolled in prospective cohort study. The control group was established of 80 untreated eyes of 40 patients with ocular hypertension and 80 eyes of 40 patients with no ocular pathology. Following parameters were evaluated: intraocular pressure (IOPg,IOPcc), hysteresis (CH), corneal resistance factor (CRF) and central corneal thickness (CCT). The parameters were evaluated at baseline (untreated) and in follow up periods of 3, 6, 9 and 12 months. The same schedule was used for eyes in the control group. Eyes with POAG or OH were sorted into two groups depending on the type of applied medication: prostaglandin analogues, carboanhydrase inhibitors alone or combined with betablockers. We did not prove any statistically significant difference in hysteresis in patients with newly diagnosed POAG (yet untreated) in comparison with normal eyes in control group (p = 0.238). We proved significantly higher values of CRF (p = 0.032) and CCT (p = 0.013) in the control group of untreated patients with ocular hypertension. This result confirms higher number of patients with stiffer and thicker corneas. Statistically significant difference of CH and CRF was proved (p eyes treated by prostaglandin analogues during follow up period. In these eyes we also demonstrated reduction of CCT (p < 0.001). We did not record any other statistically significant change in remaining followed parameters. Increase of CH and CRF can show change of biomechanical properties of the cornea after long-term use of prostaglandin analogues. The biomechanical properties of the cornea were not impacted by carboanhydrase inhibitors. Further studies are required to establish the effect of long-term use prostaglandin analogues on accuracy

  8. Triterpenoid resinous metabolites from the genus Boswellia: pharmacological activities and potential species-identifying properties

    Science.gov (United States)

    2013-01-01

    The resinous metabolites commonly known as frankincense or olibanum are produced by trees of the genus Boswellia and have attracted increasing popularity in Western countries in the last decade for their various pharmacological activities. This review described the pharmacological specific details mainly on anti-inflammatory, anti-carcinogenic, anti-bacterial and apoptosis-regulating activities of individual triterpenoid together with the relevant mechanism. In addition, species-characterizing triterpenic markers with the methods for their detection, bioavailability, safety and other significant properties were reviewed for further research. PMID:24028654

  9. Can fear extinction be enhanced? A review of pharmacological and behavioral findings.

    Science.gov (United States)

    Fitzgerald, Paul J; Seemann, Jocelyn R; Maren, Stephen

    2014-06-01

    There is considerable interest, from both a basic and clinical standpoint, in gaining a greater understanding of how pharmaceutical or behavioral manipulations alter fear extinction in animals. Not only does fear extinction in rodents model exposure therapy in humans, where the latter is a cornerstone of behavioral intervention for anxiety disorders such as post-traumatic stress disorder and specific phobias, but also understanding more about extinction provides basic information into learning and memory processes and their underlying circuitry. In this paper, we briefly review three principal approaches that have been used to modulate extinction processes in animals and humans: a purely pharmacological approach, the more widespread approach of combining pharmacology with behavior, and a purely behavioral approach. The pharmacological studies comprise modulation by: brain derived neurotrophic factor (BDNF), d-cycloserine, serotonergic and noradrenergic drugs, neuropeptides, endocannabinoids, glucocorticoids, histone deacetylase (HDAC) inhibitors, and others. These studies strongly suggest that extinction can be modulated by drugs, behavioral interventions, or their combination, although not always in a lasting manner. We suggest that pharmacotherapeutic manipulations provide considerable promise for promoting effective and lasting fear reduction in individuals with anxiety disorders. This article is part of a Special Issue entitled 'Memory enhancement'. Copyright © 2014 Elsevier Inc. All rights reserved.

  10. Pharmacologic increase in HIF1α enhances hematopoietic stem and progenitor homing and engraftment.

    Science.gov (United States)

    Speth, Jennifer M; Hoggatt, Jonathan; Singh, Pratibha; Pelus, Louis M

    2014-01-09

    Hematopoietic stem cell (HSC) transplantation is a lifesaving therapy for a number of immunologic disorders. For effective transplant, HSCs must traffic from the peripheral blood to supportive bone marrow niches. We previously showed that HSC trafficking can be enhanced by ex vivo treatment of hematopoietic grafts with 16-16 dimethyl prostaglandin E2 (dmPGE2). While exploring regulatory molecules involved in dmPGE2 enhancement, we found that transiently increasing the transcription factor hypoxia-inducible factor 1-α (HIF1α) is required for dmPGE2-enhanced CXCR4 upregulation and enhanced migration and homing of stem and progenitor cells and that pharmacologic manipulation of HIF1α is also capable of enhancing homing and engraftment. We also now identify the specific hypoxia response element required for CXCR4 upregulation. These data define a precise mechanism through which ex vivo pulse treatment with dmPGE2 enhances the function of hematopoietic stem and progenitor cells; these data also define a role for hypoxia and HIF1α in enhancement of hematopoietic transplantation.

  11. Characterization and pharmacological properties of a novel multifunctional Kunitz inhibitor from Erythrina velutina seeds.

    Directory of Open Access Journals (Sweden)

    Richele J A Machado

    Full Text Available Inhibitors of peptidases isolated from leguminous seeds have been studied for their pharmacological properties. The present study focused on purification, biochemical characterization and anti-inflammatory and anticoagulant evaluation of a novel Kunitz trypsin inhibitor from Erythrina velutina seeds (EvTI. Trypsin inhibitors were purified by ammonium sulfate (30-60%, fractionation followed by Trypsin-Sepharose affinity chromatography and reversed-phase high performance liquid chromatography. The purified inhibitor showed molecular mass of 19,210.48 Da. Furthermore, a second isoform with 19,228.16 Da was also observed. The inhibitor that showed highest trypsin specificity and enhanced recovery yield was named EvTI (P2 and was selected for further analysis. The EvTI peptide fragments, generated by trypsin and pepsin digestion, were further analyzed by MALDI-ToF-ToF mass spectrometry, allowing a partial primary structure elucidation. EvTI exhibited inhibitory activity against trypsin with IC50 of 2.2×10(-8 mol.L(-1 and constant inhibition (Ki of 1.0×10(-8 mol.L(-1, by a non-competitive mechanism. In addition to inhibit the activity of trypsin, EvTI also inhibited factor Xa and neutrophil elastase, but do not inhibit thrombin, chymotrypsin or peptidase 3. EvTI was investigated for its anti-inflammatory and anti-coagulant properties. Firstly, EvTI showed no cytotoxic effect on human peripheral blood cells. Nevertheless, the inhibitor was able to prolong the clotting time in a dose-dependent manner by using in vitro and in vivo models. Due to anti-inflammatory and anticoagulant EvTI properties, two sepsis models were here challenged. EvTI inhibited leukocyte migration and specifically acted by inhibiting TNF-α release and stimulating IFN-α and IL-12 synthesis. The data presented clearly contribute to a better understanding of the use of Kunitz inhibitors in sepsis as a bioactive agent capable of interfering in blood coagulation and inflammation.

  12. Life context of pharmacological academic performance enhancement among university students--a qualitative approach.

    Science.gov (United States)

    Hildt, Elisabeth; Lieb, Klaus; Franke, Andreas Günter

    2014-03-07

    Academic performance enhancement or cognitive enhancement (CE) via stimulant drug use has received increasing attention. The question remains, however, whether CE solely represents the use of drugs for achieving better academic or workplace results or whether CE also serves various other purposes. The aim of this study was to put the phenomenon of pharmacological academic performance enhancement via prescription and illicit (psycho-) stimulant use (Amphetamines, Methylphenidate) among university students into a broader context. Specifically, we wanted to further understand students' experiences, the effects of use on students and other factors, such as pressure to perform in their academic and private lives. A sample of 18 healthy university students reporting the non-medical use of prescription and illicit stimulants for academic performance enhancement was interviewed in a face-to-face setting. The leading questions were related to the situations and context in which the students considered the non-medical use of stimulants. Based on the resultant transcript, two independent raters identified six categories relating to the life context of stimulant use for academic performance enhancement: Context of stimulant use beyond academic performance enhancement, Subjective experience of enhancement, Timing of consumption, Objective academic results, Side effects, Pressure to perform. The answers reveal that academic performance enhancement through the use of stimulants is not an isolated phenomenon that solely aims at enhancing cognition to achieve better academic results but that the multifaceted life context in which it is embedded is of crucial relevance. The participants not only considered the stimulants advantageous for enhancing academic performance, but also for leading an active life with a suitable balance between studying and time off. The most common reasons given for stimulant use were to maximize time, to increase motivation and to cope with memorizing

  13. A preliminary study on cognitive enhancer consumption behaviors and motives of French Medicine and Pharmacology students.

    Science.gov (United States)

    Micoulaud-Franchi, J-A; MacGregor, A; Fond, G

    2014-07-01

    Pharmaceutical neuroenhancer consumption in college students is a rather unknown phenomenon in Europe and particularly in France, where surprisingly only one study was conducted in 1988. Our objective is to assess prevalence and motivations for licit (use inside medical indication) and illicit pharmaceutical neuroenhancer consumption (tablet form) in a non-selected French sample of Medicine and Pharmacology students. A validated questionnaire was send to French sample of Medicine and Pharmacology students using email. The questionnaire investigate motives for use of pharmaceutical licit (vitamin C and caffeine tablets) and illicit (methylphenidate, amphetamines, modafinil, piracetam). Among 206 undergraduate students, 139 students (67.4%) declared to have consumed at least one cognitive enhancer in the past 12 months. Twelve students (8.6% of cognitive enhancers users and 5.8% of our total sample) used illicit pharmaceutical neuroenhancer. The motivations were first to improve their academic performances, second to improve their wakefulness/ vigilance, and third to improve their attention/concentration. Neuroenhancement is a widespread means of using pharmaceutical drugs in French as well as in US college campuses. Despites some limitations, these preliminary results highlight the need to boost the interest of professionals for the neuroenhancement issue in French and European students.

  14. Medicinal plants of the family Caryophyllaceae: a review of ethno-medicinal uses and pharmacological properties

    Directory of Open Access Journals (Sweden)

    Satish Chandra

    2015-09-01

    Full Text Available Several species of the family Caryophyllaceae are widely used by many ethnic communities as traditional medicine throughout the world. The highest number of plants of the family are used in Chinese traditional medicine. The ethnopharmacologial studies of this family indicate that plants of the family possess anticancer, antibacterial, antifungal, antiviral, antioxidant, and anti-inflammatory properties. Other miscellaneous properties reported are ribosome inactivation properties, inhibition of prostatic enlargement in rats, and inhibition of intestinal enzyme carboxyelasterase in rats, cerebro-protective activity, and antiobesity in rats. Few reviews have been published yet, providing information regarding medicinal plants of the family and their biomedical properties. All published reviews have focused either on a particular taxa or a few species. The present review is focused on the traditional medicinal uses of the plants of the family Caryophyllaceae along with phytochemical and pharmacological studies of the family. A study of the literature revealed significant traditional medicinal importance of the family. Major chemical constituents of Caryophyllceae are saponins, Phytoecdysteroids, benzenoids, phenyl propanoids, and nitrogen containing compounds. The most important property of plants of the family is anticancer activity and is shown by the large number of plant species studied. This review of traditional medicinal and pharmacological uses of plants of the family, provide a ground for future research in the family.

  15. An overview on phytochemical and pharmacological properties of Rhus coriaria L.

    Directory of Open Access Journals (Sweden)

    J. Asgarpanah

    2014-04-01

    Full Text Available Rhus coriaria L. is known as Sumac. R. coriaria extracts are important in drug development with numerous pharmacological reputations in the South-Eastern Anatolia, Mediterranean area and Western Asia especially in Iran. Regarding the new multi-functional properties of R. coriaria and the related valuable ongoing reports, we were prompted to review the phytochemical and pharmacological properties of this species. The data were collected using scientific journals, books and websites such as Scopus, PubMed and Google Scholar. For a long time, R. coriaria has been used as a spice by grinding the dried fruits with salt, and it has also been widely used as a medicinal herb in traditional medicine for its atheroprotective effect and its ability to treat eye diseases, wounds, bowel disorders, ring worms and skin disorders. In addition, R. coriaria has recently shown to have hepatoprotective, anti-ischemic, antimicrobial as well as hypoglycemic and hyperlipidemic effects. Volatile substances, flavonoids, tannins and xanthones have been reported from this plant. Due to its easy collection and the remarkable biological activities, R. coriaria has been used both as food and medicine in some parts of the world especially Iran. This article presents comprehensive analyzed information on the botanical, chemical and pharmacological aspects of R. coriaria.

  16. Prediction of the Carcinogenic Potential of Human Pharmaceuticals Using Repeated Dose Toxicity Data and Their Pharmacological Properties.

    Science.gov (United States)

    van der Laan, Jan Willem; Buitenhuis, Wenny H W; Wagenaar, Laura; Soffers, Ans E M F; van Someren, Eugene P; Krul, Cyrille A M; Woutersen, Ruud A

    2016-01-01

    In an exercise designed to reduce animal use, we analyzed the results of rat subchronic toxicity studies from 289 pharmaceutical compounds with the aim to predict the tumor outcome of carcinogenicity studies in this species. The results were obtained from the assessment reports available at the Medicines Evaluation Board of the Netherlands for 289 pharmaceutical compounds that had been shown to be non-genotoxic. One hundred forty-three of the 239 compounds not inducing putative preneoplastic lesions in the subchronic study did not induce tumors in the carcinogenicity study [true negatives (TNs)], whereas 96 compounds were categorized as false negatives (FNs) because tumors were observed in the carcinogenicity study. Of the remaining 50 compounds, 31 showed preneoplastic lesions in the subchronic study and tumors in the carcinogenicity study [true positives (TPs)], and 19 only showed preneoplastic lesions in subchronic studies but no tumors in the carcinogenicity study [false positives (FPs)]. In addition, we then re-assessed the prediction of the tumor outcome by integrating the pharmacological properties of these compounds. These pharmacological properties were evaluated with respect to the presence or absence of a direct or indirect proliferative action. We found support for the absence of cellular proliferation for 204 compounds (TN). For 67 compounds, the presence of cellular hyperplasia as evidence for proliferative action could be found (TP). Therefore, this approach resulted in an ability to predict non-carcinogens at a success rate of 92% and the ability to detect carcinogens at 98%. The combined evaluation of pharmacological and histopathological endpoints eventually led to only 18 unknown outcomes (17 categorized as FN and 1 as FP), thereby enhancing both the negative and positive predictivity of an evaluation based upon histopathological evaluation only. The data show the added value of a consideration of the pharmacological properties of compounds in

  17. Prediction of the carcinogenic potential of human pharmaceuticals using repeated dose toxicity data and their pharmacological properties

    Directory of Open Access Journals (Sweden)

    Jan Willem Van Der Laan

    2016-10-01

    Full Text Available In an exercise designed to reduce animal use, we analysed the results of rat sub-chronic toxicity studies from 289 pharmaceutical compounds with the aim to predict the tumour outcome of carcinogenicity studies in this species. The results were obtained from the assessment reports available at the Medicines Evaluation Board of the Netherlands for 289 pharmaceutical compounds that had been shown to be non-genotoxic. One hundred and forty-three of the 239 compounds not inducing putative preneoplastic lesions in the sub-chronic study did not induce tumours in the carcinogenicity study (True Negatives - TN, whereas 96 compounds were categorised as False Negatives (FN, because tumours were observed in the carcinogenicity study. For the remaining 50 compounds, 31 showed preneoplastic lesions in the subchronic study and tumours in the carcinogenicity study (True positives - TP, and 19 only showed preneoplastic lesions in subchronic studies but no tumours in the carcinogenicity study (False positives - FP. In addition, we then re-assessed the prediction of the tumour outcome by integrating the pharmacological properties of these compounds. These pharmacological properties were evaluated with respect to the presence or absence of a direct or indirect proliferative action. We found support for the absence of cellular proliferation for 204 compounds (TN. For 67 compounds the presence of cellular hyperplasia as evidence for proliferative action could be found (TP. Therefore, this approach resulted in an ability to predict non-carcinogens at a success rate of 92 % and the ability to detect carcinogens at 98 %. The combined evaluation of pharmacological and histopathological endpoints eventually led to only 18 unknown outcomes (17 categorised as FN. 1 as FP, thereby enhancing both the negative and positive predictivity of an evaluation based upon histopathological evaluation only. The data show the added value of a consideration of the pharmacological

  18. Ethnopharmacological Uses, Phytochemistry, and Pharmacological Properties of Croton macrostachyus Hochst. Ex Delile: A Comprehensive Review

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    Alfred Maroyi

    2017-01-01

    Full Text Available Croton macrostachyus is widely used as herbal medicine by the indigenous people of tropical Africa. The potential of C. macrostachyus as herbal medicine, the phytochemistry, and pharmacological properties of its parts used as herbal medicines are reviewed. The extensive literature survey revealed that C. macrostachyus is traditionally used to treat or manage at least 81 human and animal diseases and ailments. The species is used as herbal medicine for diseases and ailments such as abdominal pains, cancer, gastrointestinal disorders, malaria, pneumonia, sexually transmitted infections, skin infections, typhoid, and wounds and as ethnoveterinary medicine. Multiple classes of phytochemicals such as alkaloids, amino acids, anthraquinones, carbohydrates, cardiac glycosides, coumarins, essential oil, fatty acids, flavonoids, phenolic compounds, phlobatannins, polyphenols, phytosteroides, saponins, sterols, tannins, terpenoids, unsaturated sterol, vitamin C, and withanoides have been isolated from the species. Pharmacological studies on C. macrostachyus indicate that it has a wide range of pharmacological activities such as anthelmintic, antibacterial, antimycobacterial, antidiarrhoeal, antifungal, anticonvulsant and sedative, antidiabetic, anti-inflammatory, antileishmanial, antioxidant, antiplasmodial, and larvicidal effects. Croton macrostachyus has potential as a possible source of a wide range of pharmaceutical products for the treatment of a wide range of both human and animal diseases and ailments.

  19. Pharmacological Mechanisms of Cortical Enhancement Induced by the Repetitive Pairing of Visual/Cholinergic Stimulation.

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    Jun-Il Kang

    Full Text Available Repetitive visual training paired with electrical activation of cholinergic projections to the primary visual cortex (V1 induces long-term enhancement of cortical processing in response to the visual training stimulus. To better determine the receptor subtypes mediating this effect the selective pharmacological blockade of V1 nicotinic (nAChR, M1 and M2 muscarinic (mAChR or GABAergic A (GABAAR receptors was performed during the training session and visual evoked potentials (VEPs were recorded before and after training. The training session consisted of the exposure of awake, adult rats to an orientation-specific 0.12 CPD grating paired with an electrical stimulation of the basal forebrain for a duration of 1 week for 10 minutes per day. Pharmacological agents were infused intracortically during this period. The post-training VEP amplitude was significantly increased compared to the pre-training values for the trained spatial frequency and to adjacent spatial frequencies up to 0.3 CPD, suggesting a long-term increase of V1 sensitivity. This increase was totally blocked by the nAChR antagonist as well as by an M2 mAChR subtype and GABAAR antagonist. Moreover, administration of the M2 mAChR antagonist also significantly decreased the amplitude of the control VEPs, suggesting a suppressive effect on cortical responsiveness. However, the M1 mAChR antagonist blocked the increase of the VEP amplitude only for the high spatial frequency (0.3 CPD, suggesting that M1 role was limited to the spread of the enhancement effect to a higher spatial frequency. More generally, all the drugs used did block the VEP increase at 0.3 CPD. Further, use of each of the aforementioned receptor antagonists blocked training-induced changes in gamma and beta band oscillations. These findings demonstrate that visual training coupled with cholinergic stimulation improved perceptual sensitivity by enhancing cortical responsiveness in V1. This enhancement is mainly mediated by n

  20. Enhanced pharmacological activity of vitamin B₁₂ and penicillin as nanoparticles.

    Science.gov (United States)

    Yariv, Inbar; Lipovsky, Anat; Gedanken, Aharon; Lubart, Rachel; Fixler, Dror

    2015-01-01

    Sonochemistry has become a well-known technique for fabricating nanomaterials. Since one of the advantages of nanomaterials is that they have higher chemical activities compared with particles in the bulk form, efforts are being made to produce nano organic compounds with enhanced biological activities that could be exploited in the medical area. This study uses the sonication technique to prepare nano Vitamin B12 and nano Penicillin, and demonstrates their enhanced biological and pharmacological activity. The size and morphology of the nano Penicillin and nano Vitamin B12 were investigated using electron microscopy as well as dynamic light scattering techniques. The sizes of Penicillin and Vitamin B12 nanoparticles (NPs) were found to be 70 and 120-180 nm, respectively. The bactericidal effect of nano Penicillin was studied and found to be higher than that of the bulk form. Reducing the size of Vitamin B12 resulted in their enhanced antioxidative activity as observed using the electron paramagnetic spectroscopy technique. The penetration depth of these organic NPs can be detected by an optical iterative method. It is believed that nano organic drugs fabrication will have a great impact on the medical field.

  1. Treatments that enhance physical properties of wood

    Science.gov (United States)

    Roger M. Rowell; Peggy Konkol

    1987-01-01

    This paper was prepared for anyone who wants to know more about enhancing wood’s physical properties, from the amateur wood carver to the president of a forest products company. The authors describe chemical and physical treatments of wood that enhance the strength, stiffness, water repellency, and stability of wood. Five types of treatments are described: 1. water-...

  2. Genetic or pharmacological blockade of noradrenaline synthesis enhances the neurochemical, behavioural, and neurotoxic effects of methamphetamine

    Science.gov (United States)

    Weinshenker, David; Ferrucci, Michela; Busceti, Carla L.; Biagioni, Francesca; Lazzeri, Gloria; Liles, L. Cameron; Lenzi, Paola; Murri, Luigi; Paparelli, Antonio; Fornai, Francesco

    2008-01-01

    N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4) lesions of the locus coeruleus (LC), the major brain noradrenergic nucleus, exacerbate the damage to nigrostriatal dopamine (DA) terminals caused by the psychostimulant methamphetamine (METH). However, because noradrenergic terminals contain other neuromodulators and the noradrenaline (NA) transporter, which may act as a neuroprotective buffer, it was unclear whether this enhancement of METH neurotoxicity was caused by the loss of noradrenergic innervation or the loss of NA itself. We addressed the specific role of NA by comparing the effects of METH in mice with noradrenergic lesions (DSP-4) and those with intact noradrenergic terminals but specifically lacking NA (genetic or acute pharmacological blockade of the NA biosynthetic enzyme dopamine β-hydroxylase; DBH). We found that genetic deletion of DBH (DBH −/− mice) and acute treatment of wild-type mice with a DBH inhibitor (fusaric acid) recapitulated the effects of DSP-4 lesions on METH responses. All three methods of NA depletion enhanced striatal DA release, extracellular oxidative stress (as measured by in vivo microdialysis of DA and 2,3-dihydroxybenzoic acid), and behavioural stereotypies following repeated METH administration. These effects accompanied a worsening of the striatal DA neuron terminal damage and ultrastructural changes to medium spiny neurons. We conclude that NA itself is neuroprotective and plays a fundamental role in the sensitivity of striatal DA terminals to the neurochemical, behavioural, and neurotoxic effects of METH. PMID:18042179

  3. Genetic or pharmacological blockade of noradrenaline synthesis enhances the neurochemical, behavioral, and neurotoxic effects of methamphetamine.

    Science.gov (United States)

    Weinshenker, David; Ferrucci, Michela; Busceti, Carla L; Biagioni, Francesca; Lazzeri, Gloria; Liles, L Cameron; Lenzi, Paola; Pasquali, Livia; Murri, Luigi; Paparelli, Antonio; Fornai, Francesco

    2008-04-01

    N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4) lesions of the locus coeruleus, the major brain noradrenergic nucleus, exacerbate the damage to nigrostriatal dopamine (DA) terminals caused by the psychostimulant methamphetamine (METH). However, because noradrenergic terminals contain other neuromodulators and the noradrenaline (NA) transporter, which may act as a neuroprotective buffer, it was unclear whether this enhancement of METH neurotoxicity was caused by the loss of noradrenergic innervation or the loss of NA itself. We addressed the specific role of NA by comparing the effects of METH in mice with noradrenergic lesions (DSP-4) and those with intact noradrenergic terminals but specifically lacking NA (genetic or acute pharmacological blockade of the NA biosynthetic enzyme dopamine beta-hydroxylase; DBH). We found that genetic deletion of DBH (DBH-/- mice) and acute treatment of wild-type mice with a DBH inhibitor (fusaric acid) recapitulated the effects of DSP-4 lesions on METH responses. All three methods of NA depletion enhanced striatal DA release, extracellular oxidative stress (as measured by in vivo microdialysis of DA and 2,3-dihydroxybenzoic acid), and behavioral stereotypies following repeated METH administration. These effects accompanied a worsening of the striatal DA neuron terminal damage and ultrastructural changes to medium spiny neurons. We conclude that NA itself is neuroprotective and plays a fundamental role in the sensitivity of striatal DA terminals to the neurochemical, behavioral, and neurotoxic effects of METH.

  4. Pharmacological cognitive enhancement – how future neuroscientific research could advance ethical debate

    Directory of Open Access Journals (Sweden)

    Hannah eMaslen

    2014-06-01

    Full Text Available There are numerous ways people can improve their cognitive capacities: good nutrition and regular exercise can produce long-term improvements across many cognitive domains, whilst commonplace stimulants such as coffee temporarily boost levels of alertness and concentration. Effects like these have been well-documented in the medical literature and they raise few (if any ethical issues. More recently, however, clinical research has shown that the off-label use of some pharmaceuticals can, under certain conditions, have modest cognition-improving effects. Substances such as methylphenidate and modafinil can improve capacities such as working memory and concentration in some healthy individuals. Unlike their more mundane predecessors, these methods of ‘cognitive enhancement’ are thought to raise a multitude of ethical issues. This paper presents the six principal ethical issues raised in relation to pharmacological cognitive enhancers (PCEs – issues such as whether: (1 the medical safety-profile of PCEs justifies restricting or permitting their elective or required use; (2 the enhanced mind can be an ‘authentic’ mind; (3 individuals might be coerced into using PCEs; (4, there is a meaningful distinction to be made between the treatment versus enhancement effect of the same PCE; (5 unequal access to PCEs would have implications for distributive justice; and (6 PCE use constitutes cheating in competitive contexts. In reviewing the six principal issues, the paper discusses how future neuroscientific research might help advance the ethical debate. In particular, the paper presents new arguments about the contribution neuroscience could make to debates about justice, fairness and cheating, ultimately concluding that neuroscientific research into ‘personalised enhancement’ will be essential if policy is to be truly informed and ethical. We propose an ‘ethical agenda’ for neuroscientific research into PCEs.

  5. Traditional uses, phytochemistry and pharmacological properties of Neolamarckia cadamba: A review.

    Science.gov (United States)

    Pandey, Arti; Negi, Pradeep Singh

    2016-04-02

    There are more than 3000 officially documented plants in the Indian subcontinent that hold great medicinal potential. One such under-explored plant is an evergreen tropical tree Neolamarckia cadamba (Roxb.) Bosser (Rubiaceae). It is widely distributed in tropical and subtropical regions of the world and has therapeutic potential against many diseases such as diabetes, anaemia, stomatitis, leprosy, cancer and infectious diseases. Neolamarckia cadamba has historical existence in India and it is mentioned in mythical stories. There are several reports on medicinal values of root, bark and leaves of N. cadamba; but the literature on its fruits is scanty. Therefore, the present review aims to provide updated comprehensive information on the phytochemistry and pharmacological properties of different parts of N. cadamba tree with special reference to its fruit, in order to open new perspectives for future food and pharmacological research. A literature search was performed on N. cadamba using ethnobotanical textbooks, published articles in peer-reviewed journals, unpublished materials, government survey reports and scientific databases such as Pubmed, Scopus, Web of Science, Science Direct, Google Scholar and other web search engines (Google, Yahoo). The Plant List, International Plant Name Index and Kew Botanical Garden Plant name databases were used to validate the scientific names. Neolamarckia cadamba is one of the economically important trees, which is being exploited for paper, pulp and wood industry. In folk medicine, various parts of N. cadamba are used in the treatment of various ailments such as fever, uterine complaints, blood diseases, skin diseases, tumour, anaemia, eye inflammation and diarrhoea. Other reported uses of N. cadamba include antihepatotoxic, antimalarial, analgesic, anti-inflammatory, antipyretic, diuretic and laxative. Various phytochemicals such as cadambine and its derivatives (dihydrocadambine and isodihydrocadambine) and indole alkaloids

  6. Phytochemical and Pharmacological Properties of Gymnema sylvestre: An Important Medicinal Plant

    Directory of Open Access Journals (Sweden)

    Pragya Tiwari

    2014-01-01

    Full Text Available Gymnema sylvestre (Asclepiadaceae, popularly known as “gurmar” for its distinct property as sugar destroyer, is a reputed herb in the Ayurvedic system of medicine. The phytoconstituents responsible for sweet suppression activity includes triterpene saponins known as gymnemic acids, gymnemasaponins, and a polypeptide, gurmarin. The herb exhibits a broad range of therapeutic effects as an effective natural remedy for diabetes, besides being used for arthritis, diuretic, anemia, osteoporosis, hypercholesterolemia, cardiopathy, asthma, constipation, microbial infections, indigestion, and anti-inflammatory. G. sylvestre has good prospects in the treatment of diabetes as it shows positive effects on blood sugar homeostasis, controls sugar cravings, and promotes regeneration of pancreas. The herbal extract is used in dietary supplements since it reduces body weight, blood cholesterol, and triglyceride levels and holds great prospects in dietary as well as pharmacological applications. This review explores the transition of a traditional therapeutic to a modern contemporary medication with an overview of phytochemistry and pharmacological activities of the herb and its phytoconstituents.

  7. Differences in direct pharmacologic effects and antioxidative properties of mature breast milk and infant formulas.

    Science.gov (United States)

    Lugonja, Nikoleta; Spasić, Snežana D; Laugier, Olga; Nikolić-Kokić, Aleksandra; Spasojević, Ivan; Oreščanin-Dušić, Zorana; Vrvić, Miroslav M

    2013-02-01

    Early-onset and exclusive breast-feeding provides a significant health benefit to infants compared with infant formulas. The aim of this study was to compare mature breast milk with standard infant formulas by examining their effects on non-vascular smooth muscle contraction and their antioxidative properties. The pharmacologic effects of breast milk and formulas were examined using a model system of the rat uterine smooth muscle contraction. Electron paramagnetic resonance spin-trapping spectroscopy was used to compare the antioxidative capacities of breast milk (obtained in the ninth week of lactation) with commercial infant formulas against hydroxyl radical production in the Fenton reaction. The activities of superoxide dismutase, glutathione peroxidase, and the sulfhydryl group were determined in the breast milk and infant formulas. In contrast to the infant formulas, breast milk exerted a relaxing effect on isolated non-vascular smooth muscle. In general, breast milk showed higher antioxidative activity compared with the infant formulas. In all samples, the generation of hydroxyl radicals led to the formation of carbon-centered and ascorbyl radicals. Human milk exerts direct pharmacologic relaxation effects and provides better antioxidant protection compared with infant formulas because of the presence of specific enzymatic components, such as human superoxide dismutase. We propose that these effects should be advantageous to an infant's gastrointestinal tract by supporting the normal work of the smooth musculature and maintaining redox homeostasis and may represent one of the mechanisms by which breast-feeding benefits health. Copyright © 2013 Elsevier Inc. All rights reserved.

  8. Ethnobotany, phytochemistry, toxicology and pharmacological properties of Terminalia sericea Burch. ex DC. (Combretaceae) - A review.

    Science.gov (United States)

    Mongalo, N I; McGaw, L J; Segapelo, T V; Finnie, J F; Van Staden, J

    2016-12-24

    The use of medicinal plants in the treatment of infections is ancient. A wide variety of ethnotherapeutic properties and pharmacological actions has been attributed to Terminalia sericea. Studies by various groups of investigators reveal that it is a multipurpose medicinal plant used mostly in the treatment of diarrhoea, sexually transmitted infections, skin rashes, tuberculosis and other infections. The current paper is aimed at providing an overview of the ethnomedicinal uses, toxicology, pharmacology and the phytochemistry of Terminalia sericea. Information was retrieved using various search engines, including Pubmed, Science Direct, Google Scholar, Scielo, SciFinder and Scopus. The key words used included Terminalia sericea, secondary metabolites, phytochemistry, biological activity, pharmacology, ethnobotanical survey, medicinal uses, safety, toxicology and other related words. Terminalia sericea is an important medicinal plant which possesses anti-HIV, anti-fungal, anti-bacterial, anticancer, lipolytic, wound healing, antiparasitic, anti-inflammatory and anti-oxidant activity, as the most valuable biological activities, thus lending pharmacological support to the plant's folkloric uses in indigenous medicine. Toxicologically, the extracts and isolated compounds from the plant species may have mild toxic effects. Phytochemically, the plant species possesses valuable compounds including triterpenes, alkaloids and flavonoids which may well contribute to its biological activity. Terminalia sericea contains secondary metabolites which are valuable in the treatment of a variety of human infections, including community acquired infections which may be prevalent in developing countries. The degree of toxicity reported in various extracts warrants further exploration of the cytotoxicity of the plant species, both against normal human cell lines and in vivo. Moreover, the acetylcholinesterase inhibitory and anti-inflammatory effects also need to be further

  9. Human pharmacology of a performance-enhancing dietary supplement under resting and exercise conditions

    Science.gov (United States)

    Haller, Christine A; Duan, Minjing; Jacob, Peyton; Benowitz, Neal

    2008-01-01

    AIMS Dietary supplements (DS) promoted to enhance athletic performance often contain herbal sympathomimetics such as Citrus aurantium (synephrine) and caffeine. We aimed to characterize the pharmacology of a performance-enhancing DS in the setting of exercise. METHODS Ten healthy adults (three women) aged 20–31 years participated in a three-arm, double-blind, placebo-controlled, crossover study. Subjects ingested one dose of DS (Ripped Fuel Extreme Cut® with 21 mg synephrine and 304 mg caffeine by analysis) under resting conditions and 1 h prior to moderately intense exercise (30 min on cycle ergometer at 75–80% HRmax), with a placebo (PLC)/exercise control. Plasma synephrine and caffeine concentrations were measured over 12 h, and vital signs, serum electrolytes, oxygen consumption and perceived exercise exertion were monitored. RESULTS No significant adverse events occurred. Synephrine and caffeine pharmacokinetics were unaffected by exercise. Post-exercise diastolic blood pressure was higher after DS (peak mean 71.7 ± 8.7 mmHg) than PLC (63.0 ± 4.9 mmHg) (p = 0.007). There were no substantial treatment-related differences in post-exercise HR, systolic blood pressure, or temperature. Postprandial plasma glucose increased to 121.0 ± 31.6 mg dl−1 with DS and exercise vs. 103.7 ± 25.5 mg dl−1 with PLC and exercise (P = 0.004). No treatment differences in exercise-related oxygen consumption, serum lactate, or insulin were observed. Exercise was rated less difficult with DS than PLC (P = 0.001). CONCLUSIONS Blood pressure and plasma glucose increased post-exercise with DS use, which could be detrimental in some people. Exercise was perceived as less strenuous after DS, presumably due to the stimulant effects of caffeine. WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT Performance-enhancing dietary supplements have not been clinically tested for safety or efficacy. In clinical trials performed under resting conditions, performance-enhancing supplements raise

  10. Annona reticulata Linn. (Bullock's heart: Plant profile, phytochemistry and pharmacological properties

    Directory of Open Access Journals (Sweden)

    Prasad G. Jamkhande

    2015-07-01

    Full Text Available From the beginning of human civilization plants and plant based chemicals are the most important sources of medicines. Phytochemical and different products obtained from plant are used as medicines, pharmaceuticals, cosmetics and food supplements. Annona reticulata Linn. (牛心果 niú xīn guǒ; Bullock's heart is a versatile tree and its fruits are edible. Parts of A. reticulata are used as source of medicine and also for industrial products. It possesses several medicinal properties such as anthelmintic, analgesic, anti-inflammatory, antipyretic, wound healing and cytotoxic effects. It is widely distributed with phytochemicals like tannins, alkaloids, phenols, glycosides, flavonoids and steroids. Present article is an attempt to highlight over taxonomy, morphology, geographical distribution, phytoconstituents and pharmacological activities of A. reticulata reported so far.

  11. Pharmacology of the new P2Y12 receptor inhibitors: insights on pharmacokinetic and pharmacodynamic properties.

    Science.gov (United States)

    Ferri, Nicola; Corsini, Alberto; Bellosta, Stefano

    2013-10-01

    The P2Y(12) receptor is a key player in platelet activation and represents an effective pharmacological target for the inhibition of platelet aggregation and prevention of atherothrombotic events. Indeed, the clinical use of the P2Y(12) receptor inhibitor clopidogrel is an effective strategy for inhibiting platelet activity in patients with acute coronary syndrome, and for preventing thrombotic events in those undergoing percutaneous coronary intervention with stenting. However, clopidogrel has several drawbacks, which include delayed onset of action, large inter-individual variability in platelet response, genetic polymorphism of the metabolizing enzyme, drug-drug interactions (DDIs), and the two-step activation process catalyzed by a series of cytochrome P450 (CYP) isoenzymes. For these reasons, new P2Y(12) receptor inhibitors have been developed in an attempt to improve on the pharmacological and clinical profile of clopidogrel. Three new P2Y(12) receptor inhibitors--prasugrel, cangrelor, and ticagrelor--have arrived, and more are coming into clinical use. Each of these antagonists has individual properties and, according to their mechanism of inhibition, can be divided into irreversible (prasugrel) and reversible inhibitors (ticagrelor, cangrelor). These agents also have different metabolic pathways: prasugrel is a prodrug that requires metabolic activation through a cytochrome-dependent pathway, while ticagrelor and cangrelor do not require metabolic conversion. However, ticagrelor is a CYP3A4 substrate/inhibitor and thus it can be involved in DDIs. Indeed, ticagrelor significantly increases the plasma levels of CYP3A4 substrates such as statins. Moreover, concomitant use with strong CYP3A4 inhibitors (such as ketoconazole, itraconazole, clarithromycin, ritonavir, telithromycin, etc.) is contraindicated, while the co-administration of ticagrelor with potent CYP3A inducers (carbamazepine, rifampicin, phenytoin, phenobarbital) is discouraged. Prasugrel and

  12. Molecular Cloning and Pharmacological Properties of an Acidic PLA2 from Bothrops pauloensis Snake Venom

    Directory of Open Access Journals (Sweden)

    Francis Barbosa Ferreira

    2013-12-01

    Full Text Available In this work, we describe the molecular cloning and pharmacological properties of an acidic phospholipase A2 (PLA2 isolated from Bothrops pauloensis snake venom. This enzyme, denominated BpPLA2-TXI, was purified by four chromatographic steps and represents 2.4% of the total snake venom protein content. BpPLA2-TXI is a monomeric protein with a molecular mass of 13.6 kDa, as demonstrated by Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF analysis and its theoretical isoelectric point was 4.98. BpPLA2-TXI was catalytically active and showed some pharmacological effects such as inhibition of platelet aggregation induced by collagen or ADP and also induced edema and myotoxicity. BpPLA2-TXI displayed low cytotoxicity on TG-180 (CCRF S 180 II and Ovarian Carcinoma (OVCAR-3, whereas no cytotoxicity was found in regard to MEF (Mouse Embryonic Fibroblast and Sarcoma 180 (TIB-66. The N-terminal sequence of forty-eight amino acid residues was determined by Edman degradation. In addition, the complete primary structure of 122 amino acids was deduced by cDNA from the total RNA of the venom gland using specific primers, and it was significantly similar to other acidic D49 PLA2s. The phylogenetic analyses showed that BpPLA2-TXI forms a group with other acidic D49 PLA2s from the gender Bothrops, which are characterized by a catalytic activity associated with anti-platelet effects.

  13. Enhancing the magnetic properties of magnetic nanoparticles

    DEFF Research Database (Denmark)

    Ahlburg, Jakob; Saura-Múzquiz, Matilde; Stingaciu, Marian

    Enhancing the magnetic properties of magnetic nanoparticles J. V. Ahlburg, M. S. Músquiz, C. Zeuthen, S. Kjeldgaard, M. Stingaciu, M. Christensen Center for Materials Crystallography, Departement of Chemistry & iNano, Aarhus University, Denmark Strong magnets with a high energy product are vital...

  14. Microwave Enhancement in Coronal Holes: Statistical Properties

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Astrophysics and Astronomy; Volume 21; Issue 3-4. Microwave Enhancement in Coronal Holes: Statistical Properties. Ν. Gopalswamy Κ. Shibasaki Μ. Salem. Session X – Cycle Variation in the Quiet Corona & Coronal Holes Volume 21 Issue 3-4 September-December 2000 pp 413-417 ...

  15. Enhancement of Spartium junceum L. fibres properties

    Science.gov (United States)

    Kovačević, Z.; Bischof, S.; Antonović, A.

    2017-10-01

    Properties of lignocellulosic Spartium junceum L. (SJL) fibres were investigated in order to use them as reinforcement in composite material production. The fibres were obtained by microwave maceration process and additionally modified with NaOH, nanoclay and citric acid with the aim to improve their mechanical, thermal and other physical-chemical properties. Tensile and thermal properties of these natural fibres were enhanced by the different modification treatment which is investigated by the Vibrodyn/Vibroskop method and thermogravimetric analysis (TGA), whilst determination of chemical composition and fibre’s surface properties were explored using scanning electron microscope (SEM), electron dispersive spectroscopy (EDS) and elektrokinetic analyser. All the results show great improvement of nanoclay/citric acid modified SJL properties.

  16. Pharmacological Cognitive Enhancement in Healthy Individuals: A Compensation for Cognitive Deficits or a Question of Personality?

    Directory of Open Access Journals (Sweden)

    Larissa J Maier

    Full Text Available The ongoing bioethical debate on pharmacological cognitive enhancement (PCE in healthy individuals is often legitimated by the assumption that PCE will widely spread and become desirable for the general public in the near future. This assumption was questioned as PCE is not equally save and effective in everyone. Additionally, it was supposed that the willingness to use PCE is strongly personality-dependent likely preventing a broad PCE epidemic. Thus, we investigated whether the cognitive performance and personality of healthy individuals with regular nonmedical methylphenidate (MPH use for PCE differ from stimulant-naïve controls. Twenty-five healthy individuals using MPH for PCE were compared with 39 age-, sex-, and education-matched healthy controls regarding cognitive performance and personality assessed by a comprehensive neuropsychological test battery including social cognition, prosocial behavior, decision-making, impulsivity, and personality questionnaires. Substance use was assessed through self-report in an interview and quantitative hair and urine analyses. Recently abstinent PCE users showed no cognitive impairment but superior strategic thinking and decision-making. Furthermore, PCE users displayed higher levels of trait impulsivity, novelty seeking, and Machiavellianism combined with lower levels of social reward dependence and cognitive empathy. Finally, PCE users reported a smaller social network and exhibited less prosocial behavior in social interaction tasks. In conclusion, the assumption that PCE use will soon become epidemic is not supported by the present findings as PCE users showed a highly specific personality profile that shares a number of features with illegal stimulant users. Lastly, regular MPH use for PCE is not necessarily associated with cognitive deficits.

  17. Substances used and prevalence rates of pharmacological cognitive enhancement among healthy subjects.

    Science.gov (United States)

    Franke, Andreas G; Bagusat, Christiana; Rust, Sebastian; Engel, Alice; Lieb, Klaus

    2014-11-01

    Pharmacological "cognitive enhancement" (CE) is defined as the use of any psychoactive drug with the purpose of enhancing cognition, e.g. regarding attention, concentration or memory by healthy subjects. Substances commonly used as CE drugs can be categorized into three groups of drugs: (1) over-the-counter (OTC) drugs such as coffee, caffeinated drinks/energy drinks, caffeine tablets or Ginkgo biloba; (2) drugs being approved for the treatment of certain disorders and being misused for CE: drugs to treat attention-deficit/hyperactivity disorder (ADHD) such as the stimulants methylphenidate (MPH, e.g. Ritalin(®)) or amphetamines (AMPH, e.g. Attentin(®) or Adderall(®)), to treat sleep disorders such as modafinil or to treat Alzheimer's disease such as acetylcholinesterase inhibitors; (3) illicit drugs such as illicit AMPH, e.g. "speed", ecstasy, methamphetamine (crystal meth) or others. Evidence from randomized placebo-controlled trials shows that the abovementioned substances have limited pro-cognitive effects as demonstrated, e.g. regarding increased attention, increased cognitive speed or shortening of reaction times, but on the same time poses considerable safety risks on the consumers. Prevalence rates for the use of CE drugs among healthy subjects show a broad range from less than 1 % up to more than 20 %. The range in prevalence rates estimates results from several factors which are chosen differently in the available survey studies: type of subjects (students, pupils, special professions, etc.), degree of anonymity in the survey (online, face-to-face, etc.), definition of CE and substances used/misused for CE, which are assessed (OTC drugs, prescription, illicit drugs) as well as time periods of use (e.g. ever, during the past year/month/week, etc.). A clear and comprehensive picture of the drugs used for CE by healthy subjects and their adverse events and safety risks as well as comprehensive and comparable international data on the prevalence rates of

  18. Deep Learning Applications for Predicting Pharmacological Properties of Drugs and Drug Repurposing Using Transcriptomic Data.

    Science.gov (United States)

    Aliper, Alexander; Plis, Sergey; Artemov, Artem; Ulloa, Alvaro; Mamoshina, Polina; Zhavoronkov, Alex

    2016-07-05

    Deep learning is rapidly advancing many areas of science and technology with multiple success stories in image, text, voice and video recognition, robotics, and autonomous driving. In this paper we demonstrate how deep neural networks (DNN) trained on large transcriptional response data sets can classify various drugs to therapeutic categories solely based on their transcriptional profiles. We used the perturbation samples of 678 drugs across A549, MCF-7, and PC-3 cell lines from the LINCS Project and linked those to 12 therapeutic use categories derived from MeSH. To train the DNN, we utilized both gene level transcriptomic data and transcriptomic data processed using a pathway activation scoring algorithm, for a pooled data set of samples perturbed with different concentrations of the drug for 6 and 24 hours. In both pathway and gene level classification, DNN achieved high classification accuracy and convincingly outperformed the support vector machine (SVM) model on every multiclass classification problem, however, models based on pathway level data performed significantly better. For the first time we demonstrate a deep learning neural net trained on transcriptomic data to recognize pharmacological properties of multiple drugs across different biological systems and conditions. We also propose using deep neural net confusion matrices for drug repositioning. This work is a proof of principle for applying deep learning to drug discovery and development.

  19. Las propiedades farmacocinéticas del ayahuasca / The pharmacological properties of ayahuasca

    Directory of Open Access Journals (Sweden)

    Guillermo Saúl Escobar Cornejo

    2015-12-01

    Full Text Available RESUMEN Se describe las características químicas y los efectos del consumo del ayahuasca para conocer el estado actual de los descubrimientos existentes hasta la fecha sobre sus propiedades farmacocinéticas. Se realizó una revisión bibliográfica sobre estudios del ayahuasca hasta el año 2013 en inglés, español y portugués en las bases de datos de PubMed, PsycINFO, Psyke, Psicodoc y Redalyc, así como en capítulos de libros y bibliografía relacionada obtenida de investigaciones afines. Se concluye que uno de los componentes del ayahuasca, la harmina, puede ser utilizada para tratar diferentes patologías. ABSTRACT It describes the chemical characteristics and the effects of Ayahuasca consumption, in order to know the current status of the discoveries to date regarding their pharmacological properties. A literature review was performed on studies of ayahuasca until 2013 in English, Spanish, and Portuguese in the databases of PubMed, PsycINFO, Psyke, Psicodoc, and Redalyc; as well as chapters in books and literature obtained from related research. It is concluded that one of the components of ayahuasca – harmina – can be used to treat different pathologies.

  20. Tagetes lucida Cav.: Ethnobotany, phytochemistry and pharmacology of its tranquilizing properties.

    Science.gov (United States)

    Pérez-Ortega, G; González-Trujano, M E; Ángeles-López, G E; Brindis, F; Vibrans, H; Reyes-Chilpa, R

    2016-04-02

    Morelos State is one of the most important regions of Mexico where several plant species are used in traditional medicine to influence central nervous system (CNS) activity; for example Tagetes lucida Cav. To investigate the ethnobotany, phytochemistry and pharmacology of the tranquilizing properties of T. lucida aerial parts. Data on the medicinal uses of T. lucida were explored by interviewing healers and merchants of local markets in different regions of Morelos State by using a questionnaire. Anxiolytic and/or sedative-like responses of the T. lucida were investigated in experimental models in mice such as: open-field, exploration cylinder, hole-board, plus-maze, and the barbituric-induced hypnosis potentiation. The possible mechanism of action was explored in the presence of WAY100635 (0.32mg/kg, i.p.) and flumazenil (10mg/kg, i.p.) antagonists. A feasible active compound was isolated and identified by using conventional chromatography, including UHPLC and MS (DART) [M+H]+ techniques. Interviews of healers and merchants from ten local regions of Morelos State showed that they recommended T. lucida as infusion and as tincture for several culture-bound syndromes associated with the CNS. Anxiolytic and sedative-like activities of polar extracts were corroborated in the experimental models; these effects were inhibited in the presence of 5-HT1A and GABA/BDZ receptor antagonists. Dimethylfraxetin was identified as one possible active compound. The results support the anxiolytic and sedative-like properties of T. lucida in traditional medicine by involving serotonergic and GABAergic neurotransmission and coumarinic constituents. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  1. Supercritical processed starch nanosponge as a carrier for enhancement of dissolution and pharmacological efficacy of fenofibrate.

    Science.gov (United States)

    Jadhav, Nitin V; Vavia, Pradeep R

    2017-06-01

    In current study, supercritical processed starch nanosponge (SSNS) used as a carrier for poorly water soluble drug (fenofibrate) to enhance its in-vitro and in-vivo performance. SSNS was prepared by using sol- gel method and effective supercritical drying technique. Fenofibrate was loaded into the SSNS by using solvent immersion method with selected and optimized organic solvent. BET surface area of SSNS was evaluated by nitrogen adsorption/desorption analysis. SSNS and drug loaded SSNS were characterized by DSC, XRPD, FTIR, SEM, Contact angle study and evaluated for in-vitro, in-vivo studies. The results revealed that the formed SSNS material has high surface area (180m2/gm) with pore size (40 nm to 200nm). The DSC and XRPD study revealed the amorphization of drug within a SSNS. SEM study showed the continuous porous structure with differ nanosized pores of SSNS. Contact angle study showed improvement in aqueous wetting property of drug within a SSNS. In-vitro drug release study showed remarkable dissolution enhancement of SSNS formulation as compared to plain drug. In vivo pharmacodynamic study (hyperlipidaemia model) showed SNSS based formulation significantly improved the bioavailability of drug. Thus SSNS carrier system has good potential to be explored as a delivery system for poorly water soluble drugs. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Functional properties and toxin pharmacology of a dorsal root ganglion sodium channel viewed through its voltage sensors

    Science.gov (United States)

    Puopolo, Michelino; Martin-Eauclaire, Marie-France; Bean, Bruce P.

    2011-01-01

    The voltage-activated sodium (Nav) channel Nav1.9 is expressed in dorsal root ganglion (DRG) neurons where it is believed to play an important role in nociception. Progress in revealing the functional properties and pharmacological sensitivities of this non-canonical Nav channel has been slow because attempts to express this channel in a heterologous expression system have been unsuccessful. Here, we use a protein engineering approach to dissect the contributions of the four Nav1.9 voltage sensors to channel function and pharmacology. We define individual S3b–S4 paddle motifs within each voltage sensor, and show that they can sense changes in membrane voltage and drive voltage sensor activation when transplanted into voltage-activated potassium channels. We also find that the paddle motifs in Nav1.9 are targeted by animal toxins, and that these toxins alter Nav1.9-mediated currents in DRG neurons. Our results demonstrate that slowly activating and inactivating Nav1.9 channels have functional and pharmacological properties in common with canonical Nav channels, but also show distinctive pharmacological sensitivities that can potentially be exploited for developing novel treatments for pain. PMID:21670206

  3. Functional properties and toxin pharmacology of a dorsal root ganglion sodium channel viewed through its voltage sensors.

    Science.gov (United States)

    Bosmans, Frank; Puopolo, Michelino; Martin-Eauclaire, Marie-France; Bean, Bruce P; Swartz, Kenton J

    2011-07-01

    The voltage-activated sodium (Nav) channel Nav1.9 is expressed in dorsal root ganglion (DRG) neurons where it is believed to play an important role in nociception. Progress in revealing the functional properties and pharmacological sensitivities of this non-canonical Nav channel has been slow because attempts to express this channel in a heterologous expression system have been unsuccessful. Here, we use a protein engineering approach to dissect the contributions of the four Nav1.9 voltage sensors to channel function and pharmacology. We define individual S3b-S4 paddle motifs within each voltage sensor, and show that they can sense changes in membrane voltage and drive voltage sensor activation when transplanted into voltage-activated potassium channels. We also find that the paddle motifs in Nav1.9 are targeted by animal toxins, and that these toxins alter Nav1.9-mediated currents in DRG neurons. Our results demonstrate that slowly activating and inactivating Nav1.9 channels have functional and pharmacological properties in common with canonical Nav channels, but also show distinctive pharmacological sensitivities that can potentially be exploited for developing novel treatments for pain.

  4. Drosophila melanogaster "a potential model organism" for identification of pharmacological properties of plants/plant-derived components.

    Science.gov (United States)

    Panchal, Komal; Tiwari, Anand K

    2017-05-01

    Plants/plant-derived components have been used from ancient times to treat/cure several human diseases. Plants and their parts possess several chemical components that play the vital role in the improvement of human health and their life expectancy. Allopathic medicines have been playing a key role in the treatment of several diseases. Though allopathic medicines provide fast relief, long time consumption cause serious health concerns such as hyperallergic reactions, liver damage, etc. So, the study of medicinal plants which rarely cause any side effect is very important to mankind. Plants contain many health benefit properties like antioxidant, anti-aging, neuroprotective, anti-genotoxic, anti-mutagenic and bioinsecticidal activity. Thus, identification of pharmacological properties of plants/plant-derived components are of utmost importance to be explored. Several model organisms have been used to identify the pharmacological properties of the different plants or active components therein and Drosophila is one of them. Drosophila melanogaster "fruit fly" is a well understood, high-throughput model organism being used more than 110 years to study the different biological aspects related to the development and diseases. Most of the developmental and cell signaling pathways and ∼75% human disease-related genes are conserved between human and Drosophila. Using Drosophila, one can easily analyze the pharmacological properties of plants/plant-derived components by performing several assays available with flies such as survivorship, locomotor, antioxidant, cell death, etc. The current review focuses on the potential of Drosophila melanogaster for the identification of medicinal/pharmacological properties associated with plants/plant-derived components. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  5. Distinct pharmacological properties of second generation HDAC inhibitors with the benzamide or hydroxamate head group.

    Science.gov (United States)

    Beckers, Thomas; Burkhardt, Carmen; Wieland, Heike; Gimmnich, Petra; Ciossek, Thomas; Maier, Thomas; Sanders, Karl

    2007-09-01

    Advanced second generation inhibitors of histone deacetylases (HDAC) are currently used in clinical development. This study aimed at comparing the pharmacological properties of selected second generation HDAC inhibitors with the hydroxamate and benzamide head group, namely SAHA, LAQ824/LBH589, CI994, MS275 and MGCD0103. In biochemical assays using recombinant HDAC1, 3, 6 and 8 isoenzymes, SAHA and LAQ824/LBH589 behave as quite unselective HDAC inhibitors. In contrast, the benzamides CI994, MS275 and MGCD0103 are more selective, potent inhibitors of at least HDAC1 and HDAC3. All HDAC inhibitors induce histone H3 hyperacetylation, correlating with inhibition of proliferation, induction of cell differentiation and apoptosis. A broad cytotoxicity is seen across cell lines from different tumor entities with LAQ824/LBH589 being the most potent agents. The apoptosis inducing activity is evident in arrested and proliferating RKO colon cancer cells with inducible, heterologous p21(waf1) expression, indicative for a cell-cycle independent mode-of-action. Differentiation of MDA-MB468 breast cancer cells is induced by benzamide and hydroxamate analogs. The reversibility of drug action was evaluated by pulse treatment of A549 lung cancer cells. Whereas paclitaxel induced irreversible cell cycle alterations already after 6 hr treatment, HDAC inhibitor action was retarded and irreversible after >16 hr treatment. Interestingly, pulse treatment was equally effective as continous treatment. Finally, the efficacy of LAQ824, SAHA and MS275 in A549 nude mice xenografts was comparable to that of paclitaxel at well tolerated doses. We conclude that despite a different HDAC isoenzyme inhibition profile, hydroxamate and benzamide analogs as studied display similar cellular profiles. (c) 2007 Wiley-Liss, Inc.

  6. Chemical composition and pharmacological properties of the essential oils obtained seasonally from Lippia thymoides.

    Science.gov (United States)

    Silva, Fabrício Souza; Menezes, Pedro Modesto Nascimento; de Sá, Pedro Guilherme Souza; Oliveira, André Luís de Santana; Souza, Eric Alencar Araújo; Almeida, Jackson Roberto Guedes da Silva; de Lima, Julianeli Tolentino; Uetanabaro, Ana Paula Trovatti; Silva, Tânia Regina dos Santos; Peralta, Edna Dória; Lucchese, Angélica Maria

    2016-01-01

    Lippia thymoides Mart. & Schauer (Verbenaceae) is used in folk medicine to treat wounds, fever, bronchitis, rheumatism, headaches, and weakness. This study determinates the chemical composition of essential oils from L. thymoides, obtained at during each of the four seasons and correlates with pharmacological properties. Essential oils were obtained by hydrodistillation and analyzed by gas chromatography coupled to mass spectroscopy (GC-MS). Antioxidant activity was determined by DPPH free radical scavenging and β-carotene bleaching methods. The antimicrobial assays were performed by minimum inhibitory concentration (MIC) and minimum microbicidal concentration (MMC) methods. Isolated rat aorta and uterus, and guinea-pig trachea were utilized to evaluate relaxant potential in pre-contracted smooth muscle. Essential oils from leaves of L. thymoides had the sesquiterpene β-caryophyllene (17.22-26.27%) as the major constituent followed by borneol (4.45-7.36%), camphor (3.22-8.61%), camphene (2.64-5.66%), and germacrene D (4.72-6.18%). In vitro assays showed that these essential oils do not have antioxidant activity, have antimicrobial selectivity to Gram-positive bacteria Staphylococcus aureus (MIC = 0.004 mg/mL and MMC = 0.26-10.19 mg/mL) and Micrococcus luteus (MIC = 0.03 mg/mL and MMC = 8.43 mg/mL), relax isolated rat aorta (EC50 = 305-544 μg/mL, with endothelium; and EC50 = 150-283 μg/mL, without endothelium), and uterus (EC50 = 74-257 μg/mL), and minor potency, isolated guinea-pig trachea. Lippia thymoides is a source of natural products of pharmaceutical interest, being necessary additional studies to determine the substances involved in the biological activities.

  7. In vitro pharmacological properties of an indigenous medicinal plant, Artabotrys crassifolius Hook.f. & Thomson (Family: Annonaceae Juss.)

    OpenAIRE

    Tan, Kok Kwan

    2015-01-01

    The tropical rainforest of Malaysia is considered as one of the most evolved and complex ecosystems in the world that serves a vast untapped biodiversity of natural resources. Exploitation of medicinal plants for bioactive compounds is of great potential and could be an imperative source of providing new vistas for novel drug discovery and development. The study was undertaken to evaluate the in vitro pharmacological properties of Artabotrys crassifolius including antibacterial, antifungal, a...

  8. Functional Properties and Toxin Pharmacology of a Dorsal Root Ganglion Sodium Channel Viewed through its Voltage Sensors

    OpenAIRE

    Bosmans, Frank; Puopolo, Michelino; Martin-Eauclaire, Marie-France; Swartz, Kenton J.; Bean, Bruce Palmer

    2011-01-01

    The voltage-activated sodium (Nav) channel Nav1.9 is expressed in dorsal root ganglion (DRG) neurons where it is believed to play an important role in nociception. Progress in revealing the functional properties and pharmacological sensitivities of this non-canonical Nav channel has been slow because attempts to express this channel in a heterologous expression system have been unsuccessful. Here, we use a protein engineering approach to dissect the contributions of the four Nav1.9 voltage se...

  9. An Enantiomer of an Oral Small Molecule TSH Receptor Agonist Exhibits Improved Pharmacologic Properties

    Directory of Open Access Journals (Sweden)

    Susanne Neumann

    2016-07-01

    Full Text Available We are developing an orally available small molecule, allosteric TSH receptor (TSHR agonist for follow up diagnostics of patients with thyroid cancer. The agonist C2 (NCGC00161870 that we have studied so far is a racemic mixture containing equal amounts of two enantiomers, E1 and E2. As enantiomers of many drugs exhibit different pharmacologic properties, we assessed the properties of E1 and E2. We separated the two enantiomers by chiral chromatography and determined E2 as the (S-(+ isomer via crystal structure analysis. E1 and E2 were shown to bind differently to a homology model of the transmembrane domain of TSHR in which E2 was calculated to exhibit lower binding energy than E1 and was therefore predicted to be more potent than E1. In HEK293 cells expressing human TSHRs, C2, E1, and E2 were equally efficacious in stimulating cAMP production, but their potencies were different. E2 was more potent (EC50 = 18 nM than C2 (EC50 = 46 nM which was more potent than E1 (EC50 = 217 nM. In primary cultures of human thyrocytes, C2, E1, and E2 stimulated increases in thyroperoxidase mRNA of 92-, 55-, and 137-fold and in sodium-iodide symporter mRNA of 20-fold, 4-fold and 121-fold above basal levels, respectively. In mice, C2 stimulated an increase in radioactive iodine uptake of 1.5-fold and E2 of 2.8-fold above basal level, whereas E1 did not have an effect. C2 stimulated an increase in serum T4 of 2.4-fold, E1 of 1.9-fold, and E2 of 5.6-fold above basal levels, and a 5 day oral dosing regimen of E2 increased serum T4 levels comparable to recombinant human TSH (rhTSH, Thyrogen®. Thus, E2 is more effective than either C2 or E1 in stimulating thyroid function and as efficacious as rhTSH in vivo. E2 represents the next step toward developing an oral drug for patients with thyroid cancer.

  10. Pharmacology of cognitive enhancers for exposure-based therapy of fear, anxiety and trauma-related disorders

    Science.gov (United States)

    Singewald, N.; Schmuckermair, C.; Whittle, N.; Holmes, A.; Ressler, K.J.

    2015-01-01

    Pathological fear and anxiety are highly debilitating and, despite considerable advances in psychotherapy and pharmacotherapy they remain insufficiently treated in many patients with PTSD, phobias, panic and other anxiety disorders. Increasing preclinical and clinical evidence indicates that pharmacological treatments including cognitive enhancers, when given as adjuncts to psychotherapeutic approaches [cognitive behavioral therapy including extinction-based exposure therapy] enhance treatment efficacy, while using anxiolytics such as benzodiazepines as adjuncts can undermine long-term treatment success. The purpose of this review is to outline the literature showing how pharmacological interventions targeting neurotransmitter systems including serotonin, dopamine, noradrenaline, histamine, glutamate, GABA, cannabinoids, neuropeptides (oxytocin, neuropeptides Y and S, opioids) and other targets (neurotrophins BDNF and FGF2, glucocorticoids, L-type-calcium channels, epigenetic modifications) as well as their downstream signaling pathways, can augment fear extinction and strengthen extinction memory persistently in preclinical models. Particularly promising approaches are discussed in regard to their effects on specific aspects of fear extinction namely, acquisition, consolidation and retrieval, including long-term protection from return of fear (relapse) phenomena like spontaneous recovery, reinstatement and renewal of fear. We also highlight the promising translational value of the preclinial research and the clinical potential of targeting certain neurochemical systems with, for example d-cycloserine, yohimbine, cortisol, and L-DOPA. The current body of research reveals important new insights into the neurobiology and neurochemistry of fear extinction and holds significant promise for pharmacologically-augmented psychotherapy as an improved approach to treat trauma and anxiety-related disorders in a more efficient and persistent way promoting enhanced symptom

  11. Can fear extinction be enhanced? A review of pharmacological and behavioral findings

    Science.gov (United States)

    Fitzgerald, Paul J.; Seemann, Jocelyn R.; Maren, Stephen

    2014-01-01

    There is considerable interest, from both a basic and clinical standpoint, in gaining a greater understanding of how pharmaceutical or behavioral manipulations alter fear extinction in animals. Not only does fear extinction in rodents model exposure therapy in humans, where the latter is a cornerstone of behavioral intervention for anxiety disorders such as post-traumatic stress disorder and specific phobias, but also understanding more about extinction provides basic information into learning and memory processes and their underlying circuitry. In this paper, we briefly review three principal approaches that have been used to modulate extinction processes in animals and humans: a purely pharmacological approach, the more widespread approach of combining pharmacology with behavior, and a purely behavioral approach. The pharmacological studies comprise modulation by: brain derived neurotrophic factor (BDNF), d-cycloserine, serotonergic and noradrenergic drugs, neuropeptides, endocannabinoids, glucocorticoids, histone deacetylase (HDAC) inhibitors, and others. These studies strongly suggest that extinction can be modulated by drugs, behavioral interventions, or their combination, although not always in a lasting manner. We suggest that pharmacotherapeutic manipulations provide considerable promise for promoting effective and lasting fear reduction in individuals with anxiety disorders. PMID:24374101

  12. Pharmacological Activities of Sijunzi Decoction Which Are Related to Its Antioxidant Properties

    Directory of Open Access Journals (Sweden)

    Lei Ye

    2014-01-01

    Full Text Available This paper introduces the antioxidant constituents and pharmacological effects of Sijunzi decoction by looking up literatures in recent years. Sijunzi decoction is composed of Ginseng, Atractylodes, Tuckahoe, and Glycyrrhiza. The antioxidant ingredients of Sijunzi decoction include paeonol, dauricine, naringin, and isoliquiritigenin. The study has proved that it possesses wide pharmacological effects of anticardiovascular diseases, antinervous system disease, antidiabetes, antimetabolic syndrome, and antitumor. Research on the antioxidant components of Sijunzi decoction and their targets is a promising study area in the future.

  13. Plant composition, pharmacological properties and mutagenic evaluation of a commercial Zulu herbal mixture: Imbiza ephuzwato.

    Science.gov (United States)

    Ndhlala, A R; Finnie, J F; Van Staden, J

    2011-01-27

    Imbiza ephuzwato is a traditional herbal tonic made from a mixture of extracts of roots, bulbs, rhizomes and leaves of 21 medicinal plants and is used in traditional medicine as a multipurpose remedy. To compile and investigate the bioactivity and mutagenic effects of extracts of the 21 plant species used in the preparation of Imbiza ephuzwato herbal tonic. The 21 plant species used to make Imbiza ephuzwato herbal mixture were each investigated for their pharmacological properties. Petroleum ether (PE), dichloromethane (DCM), 80% ethanol (EtOH) and water extracts of the 21 plants were evaluated against two gram-positive, two gram-negative bacteria and a fungus Candida albicans. The extracts were also evaluated for their inhibitory effects against cyclooxygenase (COX-1 and -2) and acetylcholinesterase AChE enzymes. Mutagenic effects of the water extracts were evaluated using the Ames test. Gunnera perpensa and Rubia cordifolia were the only plant species used to manufacture Imbiza ephuzwato that had water extracts which showed good antibacterial activity. The extracts of G. perpensa (EtOH), Hypericum aethiopicum (DCM) and Urginea physodes (EtOH) showed the best antifungal activity. The water extracts of H. aethiopicum, G. perpensa, Drimia robusta, Vitellariopsis marginata, Scadoxus puniceus and Momordica balsamina showed percentage inhibition of COX-1 that was over 70%. For COX-2 enzyme, the water extracts of G. perpensa, Cyrtanthus obliquus, M. balsamina and Tetradenia riparia exhibited inhibitory activity above 70%. Water extracts of G. perpensa, C. obliquus, V. marginata, Asclepias fruticosa and Watsonia densiflora showed good AChE inhibitory activity (>80%). The Ames test results revealed that all the water extracts of the 21 plant species used to make Imbiza ephuzwato were non-mutagenic towards the Salmonella typhimurium TA98 strain for the assay with and without S9 metabolic activation. In contrast, Imbiza ephuzwato showed mutagenic effects after exposure to S

  14. Operculina turpethum (Linn.) Silva Manso as a Medicinal Plant Species: A Review on Bioactive Components and Pharmacological Properties.

    Science.gov (United States)

    Gupta, Shweta; Ved, Akash

    2017-01-01

    Operculina turpethum (Linn.) (OT) Silva Manso belongs to the family Convolvulaceae. This review incorporates literature for the phytochemical and pharmacological profile of OT herb. Exhaustive literature survey was done using all the details on phytochemistry and pharmacology of OT available. This herb was found to be a potent source of bioactive compounds such as α- and β-turpethein, turpethinic acids (A, B, C, D, and E), coumarins, cycloartenol, lanosta-5-ene, 24-methylene-δ-5-lanosterol, α- and β-rhamnose, β-sitosterol, lupeol, scopoletin, betulin, acrylamide, stigma-5,22dien-3-O-β-D-glucopyranoside, β-sitosterol-β-D-glucoside (H-1), 22,23-dihydro-α-spinosterol-β-D-glucoside (H-2), and salicylic acid (CH-2), which are useful in fevers, edema, ascites, anorexia, constipation, hepatosplenomegaly, hemorrhoids, cervical lymphadenitis, fistulas, constipation, chronic gout, fever, bronchitis, ulcers, hemorrhoids, tumors, obesity, jaundice, herpes, induce lacrimation, and other skin disorders. From the aerial parts of OT, four new dammarane-type saponins that are operculinosides A-D (1-4) were isolated that showed particular hepatoprotective activities. All the compounds are reported to possess pharmacological properties such as antibacterial, anti-inflammatory, analgesic, hepatoprotective, anti-arthritic, ulcer protective, antidiarrheal, antidiabetic, and cytotoxic properties.

  15. Physiological and pharmacological inductors of HSP70 enhance the antioxidative defense mechanisms of the liver and pancreas in diabetic rats.

    Science.gov (United States)

    Dimitrovska, Maja; Dervisevik, Mirsada; Cipanovska, Natasa; Gerazova, Katerina; Dinevska-Kjovkarovska, Suzana; Miova, Biljana

    2018-02-01

    Heat preconditioning (HP) is a powerful adaptive and protective phenomenon and the heat stress proteins (HSPs) it produces are an important determinant for the development of diabetic complications. Aspirin has been reported to modulate heat shock response in different organisms through increased induction of HSPs and is also known to exert antioxidative and radical scavenging effects in diabetes. We estimated the effect of physiological (heat stress: 45 min at 41 ± 0.5 °C) and pharmacological (aspirin treatment) induction of HSP70 on several parameters of oxidative state in the pancreas and liver of diabetic rats. Diabetes increased HSP70 level and decreased poly(ADP) ribose polymerase (PARP), glutathione (GSH), and glutathione peroxidase (GPx) activities in the pancreas. In the liver, there was reduction of HSP70 level, GSH concentration, and CAT activity, while GPx and GR activity were enhanced. HP of diabetic rats caused an additional increase of HSP70, GSH, and antioxidant enzymes in both organs. Pre-treatment of HP-diabetic animals with aspirin led to an additional increase of PARP and HSP70. Both HP and aspirin, as physiological and pharmacological inductors of HSP70, respectively, enhanced the antioxidative defense mechanisms of the liver and pancreas in diabetic rats.

  16. Cistanches Herba: an overview of its chemistry, pharmacology, and pharmacokinetics property.

    Science.gov (United States)

    Fu, Zhifei; Fan, Xiang; Wang, Xiaoying; Gao, Xiumei

    2017-10-17

    Cistanches Herba is an Orobanchaceae parasitic plant. As a commonly used Traditional Chinese Medicine (TCM), its traditional functions include treating kidney deficiency, impotence, female infertility and senile constipation. Chemical analysis of Cistanches Herba revealed that phenylethanoid glycosides, iridoids, lignans, oligosaccharides, and polysaccharides were the main constituents. Pharmacological studies demonstrated that Cistanches Herba exhibited neuroprotective, immunomodulatory, hormonal balancing, anti-fatigue, anti-inflammatory, hepatoprotection, anti-oxidative, anti-bacterial, anti-viral, and anti-tumor effects, etc. The aim of this review is to provide updated, comprehensive and categorized information on the phytochemistry, pharmacological research and pharmacokinetics studies of the major constituents of Cistanches Herba. The literature search was conducted by systematic searching multiple electronic databases including SciFinder, ISI Web of Science, PubMed, Google Scholar and CNKI. Information was also collected from journals, local magazines, books, monographs. To date, more than 100 compounds have been isolated from this genus, include phenylethanoid glycosides, carbohydrates, lignans, iridoids, etc. The crude extracts and isolated compounds have exhibited a wide range of in vitro and in vivo pharmacologic effects, such as neuroprotective, immunomodulatory, anti-inflammatory, hepatoprotection, anti-oxidative, anti-bacterial, and anti-tumor effects. The phenylethanoid glycosides, echinacoside and acteoside have attracted the most attention for their significantly neuropharmacology effects. Pharmacokinetic studies of echinacoside and acteoside also have also been summarized. Phenylethanoid glycosides have demonstrated wide pharmacological actions and have great clinical value if challenges such as poor bioavailability, fast and extensive metabolism are addressed. Apart from phenylethanoid glycosides, other constituents of Cistanches Herba, their

  17. Traditional uses, phytochemistry and pharmacological properties of the genus Peucedanum: a review.

    Science.gov (United States)

    Sarkhail, Parisa

    2014-10-28

    The genus Peucedanum (Apiaceae) comprising more than 120 species is widely distributed in Europe, Asia and Africa. The ethnopharmacologial history of this genus indicated that some extracts of aerial and underground parts of several Peucedanum species have been used in folk medicine for treatment of various conditions, such as cough, cramps, pain, rheumatism, asthma and angina. This review focuses on ethnopharmacological uses of Peucedanum species, as well as the phytochemical, pharmacological and toxicological studies on this genus. Through this review, I intend to highlight the known and potential effects of the Peucedanum species or their isolated compounds and show which traditional medicine uses have been supported by pharmacological investigations. Information on the Peucedanum species was collected from scientific journals, books, thesis and reports via a library and electronic search (using Google Scholar, Pubmed, Scopus, Web of Science and ScienceDirect). This review covers the available literature from 1970 to the end of September 2013. Although, there are about 120 species in this genus, so far many species have received no or little attention and most of pharmacological studies were performed on just about 20 species. Many phytochemical investigations on this genus confirmed that Peucedanum species are rich in essential oils and coumarins. The present review article shows that Peucedanum species have a wide spectrum of pharmacological activities and the most reported activities of Peucedanum plants come back to the presence of coumarins, flavonoids, phenolics and essential oils. The present review confirms that some Peucedanum species have emerged as a good source of the traditional medicine for treatment of inflammation, microbial infections, cardiopulmonary diseases and provides new insights for further investigations on isolated compounds, especially on praeruptorins, to find novel therapeutics and aid drug discovery. However, for using Peucedanum

  18. Pharmacological properties of cardiovascular histamine H1 receptor binding sites: characterisation with 2-phenylhistamines.

    Science.gov (United States)

    Carman-Krzan, M; Krzan, M; Schunack, W

    1997-04-01

    We determined and compared the molecular properties of histamine H1 receptor binding sites in bovine thoracic aorta smooth muscle and guinea pig myocardial membranes from ventricles with saturation and inhibition binding assay, using 3H-mepyramine to label the receptor and specific and selective H1 receptor agonists of the 2-phenylhistamine group as displacers of specific 3H-mepyramine binding. 3H-mepyramine binds in a saturable manner to a homogenous population of binding sites with a K(D) of 5.6 nM and a Bmax of 57 fmol/mg of protein in bovine aorta vascular smooth muscle membranes, whereas in the guinea pig myocardium high and low affinity 3H-mepyramine binding sites exist having the following molecular characteristics: a K(D) of 1.6 nM and a Bmax of 99 fmol/mg of protein (high affinity site) and a K(D) 15.0 nM and a Bmax of 466 fmol/mg of protein (low affinity site). Halogenated 2-phenylhistamines: 2-(3-fluoro-) (2-FPH), 2-(3-trifluoromethyl-) (2-triFMPH), 2-(3-chloro-) (2-CPH), 2-(3-bromo-) (2-BPH) and 2-(3-iodophenyl)histamine (2-IPH), which showed high selectivity and potency for H1 receptors in the functional pharmacological studies, were potent inhibitors of specific radioligand binding in comparison with histamine and parent nonhalogenated 2-phenylhistamine (2-PH). Their rank order of potencies and affinities differ significantly for the vascular and cardiac H1 receptor binding sites: Specific 3H-mepyramine binding to H1 receptors in bovine vascular smooth muscle membranes was displaced in a biphasic manner by 2-(3-fluoro-), 2-(3-trifluoromethyl-), 2-(3-chloro-), 2-(3-bromo-), 2-(3-iodophenyl)histamine and histamine. In guinea pig ventricular myocardium the rank order was 2-(3-iodo-), 2-(3-bromo-), histamine, 2-(3-chloro-), and 2-(3-fluorophenyl)histamine showing better correlation with the lipophilicity of the derivatives than in vascular tissue (order of lipophilicity: 2-triFMPH >2-IPH >2-BPH >2-CPH >2-FPH >2-PH). Displacement of the radioligand binding

  19. Targeting Homologous Recombination by Pharmacological Inhibitors Enhances the Killing Response of Glioblastoma Cells Treated with Alkylating Drugs.

    Science.gov (United States)

    Berte, Nancy; Piée-Staffa, Andrea; Piecha, Nadine; Wang, Mengwan; Borgmann, Kerstin; Kaina, Bernd; Nikolova, Teodora

    2016-11-01

    Malignant gliomas exhibit a high level of intrinsic and acquired drug resistance and have a dismal prognosis. First- and second-line therapeutics for glioblastomas are alkylating agents, including the chloroethylating nitrosoureas (CNU) lomustine, nimustine, fotemustine, and carmustine. These agents target the tumor DNA, forming O6-chloroethylguanine adducts and secondary DNA interstrand cross-links (ICL). These cross-links are supposed to be converted into DNA double-strand breaks, which trigger cell death pathways. Here, we show that lomustine (CCNU) with moderately toxic doses induces ICLs in glioblastoma cells, inhibits DNA replication fork movement, and provokes the formation of DSBs and chromosomal aberrations. Since homologous recombination (HR) is involved in the repair of DSBs formed in response to CNUs, we elucidated whether pharmacologic inhibitors of HR might have impact on these endpoints and enhance the killing effect. We show that the Rad51 inhibitors RI-1 and B02 greatly ameliorate DSBs, chromosomal changes, and the level of apoptosis and necrosis. We also show that an inhibitor of MRE11, mirin, which blocks the formation of the MRN complex and thus the recognition of DSBs, has a sensitizing effect on these endpoints as well. In a glioma xenograft model, the Rad51 inhibitor RI-1 clearly enhanced the effect of CCNU on tumor growth. The data suggest that pharmacologic inhibition of HR, for example by RI-1, is a reasonable strategy for enhancing the anticancer effect of CNUs. Mol Cancer Ther; 15(11); 2665-78. ©2016 AACR. ©2016 American Association for Cancer Research.

  20. Pharmacological Administration of the Isoflavone Daidzein Enhances Cell Proliferation and Reduces High Fat Diet-Induced Apoptosis and Gliosis in the Rat Hippocampus

    Science.gov (United States)

    Rivera, Patricia; Pérez-Martín, Margarita; Pavón, Francisco J.; Serrano, Antonia; Crespillo, Ana; Cifuentes, Manuel; López-Ávalos, María-Dolores; Grondona, Jesús M.; Vida, Margarita; Fernández-Llebrez, Pedro; de Fonseca, Fernando Rodríguez; Suárez, Juan

    2013-01-01

    Soy extracts have been claimed to be neuroprotective against brain insults, an effect related to the estrogenic properties of isoflavones. However, the effects of individual isoflavones on obesity-induced disruption of adult neurogenesis have not yet been analyzed. In the present study we explore the effects of pharmacological administration of daidzein, a main soy isoflavone, in cell proliferation, cell apoptosis and gliosis in the adult hippocampus of animals exposed to a very high-fat diet. Rats made obese after 12-week exposure to a standard or high-fat (HFD, 60%) diets were treated with daidzein (50 mg kg−1) for 13 days. Then, plasma levels of metabolites and metabolic hormones, cell proliferation in the subgranular zone of the dentate gyrus (SGZ), and immunohistochemical markers of hippocampal cell apoptosis (caspase-3), gliosis (GFAP and Iba-1), food reward factor FosB and estrogen receptor alpha (ERα) were analyzed. Treatment with daidzein reduced food/caloric intake and body weight gain in obese rats. This was associated with glucose tolerance, low levels of HDL-cholesterol, insulin, adiponectin and testosterone, and high levels of leptin and 17β-estradiol. Daidzein increased the number of phospho-histone H3 and 5-bromo-2-deoxyuridine (BrdU)-ir cells detected in the SGZ of standard diet and HFD-fed rats. Daidzein reversed the HFD-associated enhanced immunohistochemical expression of caspase-3, FosB, GFAP, Iba-1 and ERα in the hippocampus, being more prominent in the dentate gyrus. These results suggest that pharmacological treatment with isoflavones regulates metabolic alterations associated with enhancement of cell proliferation and reduction of apoptosis and gliosis in response to high-fat diet. PMID:23741384

  1. Melastoma malabathricum (L. Smith Ethnomedicinal Uses, Chemical Constituents, and Pharmacological Properties: A Review

    Directory of Open Access Journals (Sweden)

    S. Mohd. Joffry

    2012-01-01

    Full Text Available Melastoma malabathricum L. (Melastomataceae is one of the 22 species found in the Southeast Asian region, including Malaysia. Considered as native to tropical and temperate Asia and the Pacific Islands, this commonly found small shrub has gained herbal status in the Malay folklore belief as well as the Indian, Chinese, and Indonesian folk medicines. Ethnopharmacologically, the leaves, shoots, barks, seeds, and roots of M. malabathricum have been used to treat diarrhoea, dysentery, hemorrhoids, cuts and wounds, toothache, and stomachache. Scientific findings also revealed the wide pharmacological actions of various parts of M. malabthricum, such as antinociceptive, anti-inflammatory, wound healing, antidiarrheal, cytotoxic, and antioxidant activities. Various types of phytochemical constituents have also been isolated and identifed from different parts of M. malabathricum. Thus, the aim of the present review is to present comprehensive information on ethnomedicinal uses, phytochemical constituents, and pharmacological activities of M. malabathricum.

  2. European Viscum album: a potent phytotherapeutic agent with multifarious phytochemicals, pharmacological properties and clinical evidence

    OpenAIRE

    Singh, Brahma N.; Saha, Chaitrali; Galun, Danijel; Upreti, Dalip K.; Bayry, Jagadeesh; Kaveri, Srini V.

    2016-01-01

    International audience; Viscum album L. or European mistletoe (Loranthaceae), a semi-parasitic shrub, has been used as a traditional medicine in Europe for centuries to treat various diseases like cancer, cardiovascular disorder, epilepsy, infertility, hypertension and arthritis. V. album contains diverse phytochemicals, which exert a large number of biological and pharmacological activities. The aim of this review is to compile the developments in the domain of V. album and research trends, ...

  3. Pharmacological and therapeutic properties of valproate: a summary after 35 years of clinical experience.

    Science.gov (United States)

    Perucca, Emilio

    2002-01-01

    Thirty-five years since its introduction into clinical use, valproate (valproic acid) has become the most widely prescribed antiepileptic drug (AED) worldwide. Its pharmacological effects involve a variety of mechanisms, including increased gamma-aminobutyric acid (GABA)-ergic transmission, reduced release and/or effects of excitatory amino acids, blockade of voltage-gated sodium channels and modulation of dopaminergic and serotoninergic transmission. Valproate is available in different dosage forms for parenteral and oral use. All available oral formulations are almost completely bioavailable, but they differ in dissolution characteristics and absorption rates. In particular, sustained-release formulations are available that minimise fluctuations in serum drug concentrations during a dosing interval and can therefore be given once or twice daily. Valproic acid is about 90% bound to plasma proteins, and the degree of binding decreases with increasing drug concentration within the clinically occurring range. Valproic acid is extensively metabolised by microsomal glucuronide conjugation, mitochondrial beta-oxidation and cytochrome P450-dependent omega-, (omega-1)- and (omega-2)-oxidation. The elimination half-life is in the order of 9 to 18 hours, but shorter values (5 to 12 hours) are observed in patients comedicated with enzyme-inducing agents such as phenytoin, carbamazepine and barbiturates. Valproate itself is devoid of enzyme-inducing properties, but it has the potential of inhibiting drug metabolism and can increase by this mechanism the plasma concentrations of certain coadministered drugs, including phenobarbital (phenobarbitone), lamotrigine and zidovudine. Valproate is a broad spectrum AED, being effective against all seizure types. In patients with newly diagnosed partial seizures (with or without secondary generalisation) and/or primarily generalised tonic-clonic seizures, the efficacy of valproate is comparable to that of phenytoin, carbamazepine and

  4. Mastering languages with different rhythmic properties enhances musical rhythm perception

    NARCIS (Netherlands)

    Roncaglia-Denissen, M.Paula; Roor, Drikus; Chen, A.; Sadakata, Makiko

    Previous research suggests that mastering languages with distinct rather than similar rhythmic properties enhances musical rhythmic perception. This study investigates whether learning a second language (L2) contributes to enhanced musical rhythmic perception in general, regardless of first and

  5. Persimmon (Diospyros kaki L.) leaves: a review on traditional uses, phytochemistry and pharmacological properties.

    Science.gov (United States)

    Xie, Chunyan; Xie, Zhisheng; Xu, Xinjun; Yang, Depo

    2015-04-02

    Persimmon (Diospyros kaki L.) leaves, known as Shi Ye (in Chinese), have a long history as a Chinese traditional medicine for the treatment of ischemia stroke, angina, internal hemorrhage, hypertension, atherosclerosis and some infectious diseases, etc. Additionally, persimmon leaves could be used as healthy products, cosmetics and so on, which have become increasingly popular in Asia, such as Japan, Korea and China etc. The present paper reviewed the ethnopharmacology, phytochemistry, analytical methods, biological activities and toxicology of persimmon leaves in order to assess the ethnopharmacological use and to explore therapeutic potentials and future opportunities for research. Information on persimmon leaves were gathered via the Internet (using Google Scholar, Baidu Scholar, Elsevier, ACS, Pudmed, Web of Science, CNKI and EMBASE) and libraries. Additionally, information was also obtained from some local books. Persimmon leaves have played an important role in Chinese system of medicines. The main compositions of persimmon leaves were flavonoids, terpenoids, etc. Scientific studies on extracts and formulations revealed a wide range of pharmacological activities, such as, antioxidative, hypolipidemic, antidiabetic, antibacterial, hemostasis activities and effects on cardiovascular system. Based on the pharmacological activities, persimmon leaves were widely used in clinic including treatment of cardiovascular disease, hemostasis, antibacterial, anti-inflammatory and beauty treatment. Persimmon leaves probably have therapeutic potential in the prevention and treatment for cerebral arteriosclerosis, diabetes, hypertension. It showed significant neuroprotection against ischemia/reperfusion injury in vivo and in vitro. Moreover, it can regulate immune function and inhibite inflammation. Further investigations are needed to explore individual bioactive compounds responsible for these pharmacological effects in vitro and in vivo and the mode of actions. Further

  6. Pharmacological Enhancement of mGluR5 Facilitates Contextual Fear Memory Extinction

    Science.gov (United States)

    Sethna, Ferzin; Wang, Hongbing

    2014-01-01

    Behavioral exposure therapy, which involves extinction of the previously acquired fear, has been used to treat anxiety-related symptoms such as post-traumatic stress disorder. It has been hypothesized that proextinction pharmacotherapeutics may enhance the efficacy of exposure therapy. Systemic administration of the metabotropic glutamate receptor…

  7. Pharmacognosy, Phytochemistry and Pharmacological Properties of Achillea millefolium L.: A Review.

    Science.gov (United States)

    Ali, Sofi Imtiyaz; Gopalakrishnan, B; Venkatesalu, V

    2017-08-01

    Achillea millefoilum L. (Yarrow) is an important species of Asteraceae family with common utilization in traditional medicine of several cultures from Europe to Asia for the treatment of spasmodic gastrointestinal disorders, hepatobiliary, gynecological disorders, against inflammation and for wound healing. An extensive review of literature was made on A. millefoilum L. using ethno botanical text books, published articles in peer-reviewed journals, unpublished materials and scientific databases. The Plant List, International Plant Name Index and Kew Botanical Garden databases were used to authenticate the scientific names. Monoterpenes are the most representative metabolites constituting 90% of the essential oils in relation to the sesquiterpenes, and a wide range of chemical compounds have also been reported. Different pharmacological experiments in many in-vitro and in-vivo models have proved the potential of A. millefoilum with antiinflammatory, antiulcer, anticancer activities etc. lending support to the rationale behind numerous of its traditional uses. Due to the noteworthy pharmacological activities, A. millefoilum will be a better option for new drug discovery. The present review will comprehensively summarize the pharmacognosy, phytochemistry and ethnopharmacology of A. millefoilum reported to date, with emphasis on more in vitro, clinical and pathological studies needed to investigate the unexploited potential of this plant. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  8. Therapeutic Uses and Pharmacological Properties of Garlic, Shallot, and Their Biologically Active Compounds

    Science.gov (United States)

    Mikaili, Peyman; Maadirad, Surush; Moloudizargari, Milad; Aghajanshakeri, Shahin; Sarahroodi, Shadi

    2013-01-01

    Objective(s): Garlic (Allium sativum L. family Liliaceae) is well known in Iran and its leaves, flowers, and cloves have been used in traditional medicine for a long time. Research in recent decades has shown widespread pharmacological effects of A. sativum and its organosulfur compounds especially Allicin. Studies carried out on the chemical composition of the plant show that the most important constituents of this plant are organosulfur compounds such as allicin, diallyl disulphide, S-allylcysteine, and diallyl trisulfide. Allicin represents one of the most studied among these naturally occurring compounds. In addition to A. sativum, these compounds are also present in A. hirtifolium (shallot) and have been used to treat various diseases. This article reviews the pharmacological effects and traditional uses of A. sativum, A. hirtifolium, and their active constituents to show whether or not they can be further used as potential natural sources for the development of novel drugs. Materials and Methods: For this purpose, the authors went through a vast number of sources and articles and all needed data was gathered. The findings were reviewed and classified on the basis of relevance to the topic and a summary of all effects were reported as tables. Conclusion: Garlic and shallots are safe and rich sources of biologically active compounds with low toxicity. Further studies are needed to confirm the safety and quality of the plants to be used by clinicians as therapeutic agents. PMID:24379960

  9. Clinacanthus nutans: a review on ethnomedicinal uses, chemical constituents and pharmacological properties.

    Science.gov (United States)

    Zulkipli, Ihsan N; Rajabalaya, Rajan; Idris, Adi; Sulaiman, Nurul Atiqah; David, Sheba R

    2017-12-01

    Medicinal plants have attracted global attention for their hidden therapeutic potential. Clinacanthus nutans (Burm.f) Lindau (Acanthaceae) (CN) is endemic in Southeast Asia. CN contains phytochemicals common to medicinal plants, such as flavonoids. Traditionally, CN has been used for a broad range of human ailments including snake bites and cancer. This article compiles the ethnomedicinal uses of CN and its phytochemistry, and thus provides a phytochemical library of CN. It also discusses the known pharmacological and biological effects of CN to enable better investigation of CN. This literature review was limited to articles and websites published in the English language. MEDLINE and Google Scholar databases were searched from December 2014 to September 2016 using the following keywords: "Clinacanthus nutans" and "Belalai gajah". The results were reviewed to identify relevant articles. Information from relevant selected studies was systematically analyzed from contemporary ethnopharmacological sources, evaluated against scientific literature, and extracted into tables. The literature search yielded 124 articles which were then further scrutinized revealing the promising biological activities of CN, including antimicrobial, antiproliferative, antitumorigenic and anti-inflammatory effects. Few articles discussed the mechanisms for these pharmacological activities. Furthermore, CN was beneficial in small-scale clinical trials for genital Herpes and aphthous stomatitis. Despite the rich ethnomedicinal knowledge behind the traditional uses of CN, the current scientific evidence to support these claims remains scant. More research is still needed to validate these medicinal claims, beginning by increasing the understanding of the biological actions of this plant.

  10. Genetic or pharmacological blockade of noradrenaline synthesis enhances the neurochemical, behavioural, and neurotoxic effects of methamphetamine

    OpenAIRE

    Weinshenker, David; Ferrucci, Michela; Busceti, Carla L.; Biagioni, Francesca; Lazzeri, Gloria; Liles, L. Cameron; Lenzi, Paola; Murri, Luigi; Paparelli, Antonio; Fornai, Francesco

    2007-01-01

    N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP-4) lesions of the locus coeruleus (LC), the major brain noradrenergic nucleus, exacerbate the damage to nigrostriatal dopamine (DA) terminals caused by the psychostimulant methamphetamine (METH). However, because noradrenergic terminals contain other neuromodulators and the noradrenaline (NA) transporter, which may act as a neuroprotective buffer, it was unclear whether this enhancement of METH neurotoxicity was caused by the loss of noradrene...

  11. The genus Hippocampus--a review on traditional medicinal uses, chemical constituents and pharmacological properties.

    Science.gov (United States)

    Chen, Lu; Wang, Xiaoyu; Huang, Baokang

    2015-03-13

    Several species from the genus Hippocampus have been widely used as a traditional medicine or invigorant with long history in China. Five species of them have been recorded in Chinese pharmacopoeia with name Hippocampus (Chinese name Haima [symbol: see text]). The ethnopharmacologial history of this genus indicated that they possess anti-tumor, anti-aging, anti-fatigue, anti-prostatic hyperplasia activities and can be used for the treatment of tumor, aging, fatigue, thrombus, inflammatory, hypertension and impotence. This review focuses on the traditional medicinal uses of Hippocampus species, as well as the phytochemical, pharmacological and toxicological studies on this genus. To provide an overview of the ethnopharmacology, chemical constituents, pharmacology and clinical applications of the genus Hippocampus, and to reveal their therapeutic potentials and being an evidence base for further research works of the Hippocampus. Information on the Hippocampus species was collected from scientific journals, books, thesis and reports based on the Chinese herbal classic literature and worldwide accepted scientific databases via a library and electronic search (PubMed, Elsevier, Scopus, Google Scholar, Springer, Web of Science and CNKI). A survey of literature revealed that the major chemical constituents of Hippocampus are sterides, essential amino acids, fatty acids and microelements. Experimental evidences confirmed that the Hippocampus could be used in treating tumor, aging, fatigue, thrombus, inflammatory, hypertension, prostatic hyperplasia and impotence. The most important function of Hippocampus in TCM is invigorating kidney-yang. The key traditional uses of Hippocampus have been investigated in vitro and in vivo, but their mechanism and clinical trial data are needed, and the sustainable exploitation of the endangered Hippocampus species should be considered. This literature analysis of traditional medicinal uses and experimental chemical and pharmacological

  12. Porphyra Species: A Mini-Review of Its Pharmacological and Nutritional Properties.

    Science.gov (United States)

    Cao, Jin; Wang, Jianping; Wang, Shicheng; Xu, Ximing

    2016-02-01

    Porphyra sensu lato belongs to Bangiales, the most genetically diverse order of red algae. Porphyra or Pyropia is widely cultivated in East Asian countries, such as China, Japan, and Korea. Dried Porphyra contains numerous nutritional and biofunctional compounds, including proteins, minerals, dietary fiber, polyunsaturated fatty acids, carotenoids, saccharides, and mycosporine-like amino acids. In addition, the compound is most abundant in Porphyra, such as polysaccharides and phycobiliproteins, and demonstrates various immunomodulating, anticancer, antihyperlipidemic, and antioxidative activities. This review summarizes our current knowledge concerning the pharmacologically active substances found in Porphyra species. The biological activities and potential applications of certain carbohydrates, proteins, peptides, and other small molecules purified from Porphyra are also described, and possible areas for future studies are discussed.

  13. Traditional uses, phytochemistry and pharmacological properties of African Nauclea species: A review.

    Science.gov (United States)

    Haudecoeur, Romain; Peuchmaur, Marine; Pérès, Basile; Rome, Maxime; Taïwe, Germain Sotoing; Boumendjel, Ahcène; Boucherle, Benjamin

    2018-02-15

    The genus Nauclea in Africa comprises seven species. Among them, N. latifolia, N. diderrichii and N. pobeguinii are widely used by the local population in traditional remedies. Preparation from various parts of plants (e.g. roots, bark, leaves) are indicated by traditional healers for a wide range of diseases including malaria, pain, digestive ailments or metabolic diseases. A literature search was conducted on African species of the genus Nauclea using scientific databases such as Google Scholar, Pubmed or SciFinder. Every document of ethnopharmacological, phytochemical or pharmacological relevance and written in English or French were analyzed. The Nauclea genus is used as ethnomedicine all along sub-Saharan Africa. Several local populations consider Nauclea species as a major source of remedies for malaria. In this regard, two improved traditional medicines are currently under development using extracts from N. latifolia and N. pobeguinii. Concerning the chemical composition of the Nauclea genus, indoloquinolizidines alkaloids could be considered as the major class of compounds as they are reported in every analyzed Nauclea species, with numerous structures identified. Based on traditional indications a considerable amount of pharmacological studies were conducted to ensure activity and attempt to link them to the presence of particular compounds in plant extracts. Many experimental studies using plant extracts of the African species of the genus Nauclea validate traditional indications (e.g. malaria and pain). However, bioactive compounds are rarely identified and therefore, there is a clear need for further evaluations as well as for toxicity experiments. The sustainability of these plants, especially of N. diderrichii, a threatened species, should be kept in mind to adapt local uses and preparation modes of traditional remedies. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. PTSD-like memory generated through enhanced noradrenergic activity is mitigated by a dual step pharmacological intervention targeting its reconsolidation.

    Science.gov (United States)

    Gazarini, Lucas; Stern, Cristina A J; Piornedo, Rene R; Takahashi, Reinaldo N; Bertoglio, Leandro J

    2014-10-31

    Traumatic memories have been resilient to therapeutic approaches targeting their permanent attenuation. One of the potentially promising pharmacological strategies under investigation is the search for safe reconsolidation blockers. However, preclinical studies focusing on this matter have scarcely addressed abnormal aversive memories and related outcomes. By mimicking the enhanced noradrenergic activity reported after traumatic events in humans, here we sought to generate a suitable condition to establish whether some clinically approved drugs able to disrupt the reconsolidation of conditioned fear memories in rodents would still be effective. We report that the α2-adrenoceptor antagonist yohimbine was able to induce an inability to restrict behavioral (fear) and cardiovascular (increased systolic blood pressure) responses to the paired context when administered immediately after acquisition, but not 6h later, indicating the formation of a generalized fear memory, which endured for over 29 days and was less susceptible to suppression by extinction. It was also resistant to reconsolidation disruption by the α2-adrenoceptor agonist clonidine or cannabidiol, the major non-psychotomimetic component of Cannabis sativa. Since signaling at N-methyl-D-aspartate (NMDA) receptors is important for memory labilization and because a dysfunctional memory may be less labile than is necessary to trigger reconsolidation on its brief retrieval and reactivation, we then investigated and demonstrated that pre-retrieval administration of the partial NMDA agonist D-cycloserine allowed the disrupting effects of clonidine and cannabidiol on reconsolidation. These findings highlight the effectiveness of a dual-step pharmacological intervention to mitigate an aberrant and enduring aversive memory similar to that underlying the post-traumatic stress disorder. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  15. Formal Verification of Security Properties of Privacy Enhanced Mail

    Science.gov (United States)

    1998-06-01

    AFRL-IF-RS-TR-1998-99 Final Technical Report June 1998 FORMAL VERIFICATION OF SECURITY PROPERTIES OF PRIVACY ENHANCED MAIL Syracuse University...AND DATES COVERED Final Jun 96 - Jul 97 4. TITLE AND SUBTITLE FORMAL VERIFICATION OF SECURITY PROPERTIES OF PRIVACY ENHANCED MAIL 6. AUTHOR

  16. Cardio-ankle vascular index (CAVI) differentiates pharmacological properties of vasodilators nicardipine and nitroglycerin in anesthetized rabbits.

    Science.gov (United States)

    Chiba, Tatsuo; Yamanaka, Mari; Takagi, Sachie; Shimizu, Kazuhiro; Takahashi, Mao; Shirai, Kohji; Takahara, Akira

    2015-08-01

    Cardio-ankle vascular index (CAVI) has been developed for measurement of vascular stiffness from the aorta to tibial artery, which is clinically utilized for assessing the progress of arteriosclerosis. In this study, we established measuring system of the CAVI in rabbits, and assessed whether the index could reflect different pharmacological actions of nitroglycerin and nicardipine on the systemic vasculature. Rabbits were anesthetized with halothane, and the CAVI was calculated from the well-established basic equations with variables obtained from brachial and tibial blood pressure and phonocardiogram. Nicardipine (1, 3 and 10 μg/kg, i.v.) decreased the blood pressure, femoral vascular resistance, and heart-ankle pulse wave velocity (haPWV). Meanwhile, no significant change was detected in the CAVI at the low or middle dose, which reflects the defining feature of the CAVI that is independent of blood pressure. The index increased at the high dose. Nitroglycerin (2, 4 and 8 μg/kg, i.v.) decreased the blood pressure, femoral vascular resistance, and haPWV. Meanwhile, the CAVI was decreased during the nitroglycerin infusion, which may reflect its well-known pharmacological action dilating conduit arteries. These results suggest that the CAVI differentiates the properties of these vasodilators in vivo. Copyright © 2015 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  17. Pharmacological Inhibition of Protein Kinase G1 Enhances Bone Formation by Human Skeletal Stem Cells Through Activation of RhoA-Akt Signaling

    DEFF Research Database (Denmark)

    Kermani, Abbas Jafari; Siersbaek, Majken S; Chen, Li

    2015-01-01

    Development of novel approaches to enhance bone regeneration is needed for efficient treatment of bone defects. Protein kinases play a key role in regulation of intracellular signal transduction pathways, and pharmacological targeting of protein kinases has led to development of novel treatments...... for several malignant and nonmalignant conditions. We screened a library of kinase inhibitors to identify small molecules that enhance bone formation by human skeletal (stromal or mesenchymal) stem cells (hMSC). We identified H-8 (known to inhibit protein kinases A, C, and G) as a potent enhancer of ex vivo...... that pharmacological inhibition of PRKG1 in hMSC implanted at the site of bone defect can enhance bone regeneration. Stem Cells 2015....

  18. Enhanced fear expression in a psychopathological mouse model of trait anxiety: pharmacological interventions.

    Directory of Open Access Journals (Sweden)

    Simone B Sartori

    Full Text Available The propensity to develop an anxiety disorder is thought to be determined by genetic and environmental factors. Here we investigated the relationship between a genetic predisposition to trait anxiety and experience-based learned fear in a psychopathological mouse model. Male CD-1 mice selectively bred for either high (HAB, or normal (NAB anxiety-related behaviour on the elevated plus maze were subjected to classical fear conditioning. During conditioning both mouse lines showed increased fear responses as assessed by freezing behaviour. However, 24 h later, HAB mice displayed more pronounced conditioned responses to both a contextual or cued stimulus when compared with NAB mice. Interestingly, 6 h and already 1 h after fear conditioning, freezing levels were high in HAB mice but not in NAB mice. These results suggest that trait anxiety determines stronger fear memory and/or a weaker ability to inhibit fear responses in the HAB line. The enhanced fear response of HAB mice was attenuated by treatment with either the α(2,3,5-subunit selective benzodiazepine partial agonist L-838,417, corticosterone or the selective neurokinin-1 receptor antagonist L-822,429. Overall, the HAB mouse line may represent an interesting model (i for identifying biological factors underlying misguided conditioned fear responses and (ii for studying novel anxiolytic pharmacotherapies for patients with fear-associated disorders, including post-traumatic stress disorder and phobias.

  19. Review of Ethnomedicinal Uses, Phytochemistry and Pharmacological Properties of Euclea natalensis A.DC.

    Directory of Open Access Journals (Sweden)

    Alfred Maroyi

    2017-12-01

    Full Text Available Euclea natalensis is traditionally used as herbal medicine for several human diseases and ailments in tropical Africa. This study reviews information on ethnomedicinal uses, botany, phytochemical constituents, pharmacology and toxicity of E. natalensis. Results of this study are based on literature search from several sources including electronic databases, books, book chapters, websites, theses and conference proceedings. This study showed that E. natalensis is used as traditional medicine in 57.1% of the countries where it is indigenous. Euclea natalensis has a high degree of consensus on abdominal pains, antidote for snake bites, diabetes, diarrhoea, malaria, roundworms, stomach problems, toothache, venereal diseases and wounds. Several ethnopharmacological studies have shown that crude extracts and chemical compounds from E. natalensis demonstrated many biological activities both in vitro and in vivo, which included antibacterial, antidiabetic, antifungal, antimycobacterial, antiviral, antioxidant, antiplasmodial, larvicidal, antischistosomal, molluscicidal, dentin permeability and hepatoprotective activities. Future studies should focus on the mechanism of biological activities of both crude extracts and chemical compounds from the species, as well as structure–function relationships of bioactive constituents of the species.

  20. Synthesis and Pharmacological Properties of Novel Esters Based on Monocyclic Terpenes and GABA

    Science.gov (United States)

    Nesterkina, Mariia; Kravchenko, Iryna

    2016-01-01

    Novel esters of γ-aminobutyric acid (GABA) with monocyclic terpenes were synthesized via Steglich esterification and characterized by 1H-NMR, IR and mass spectral studies. Their anticonvulsant, analgesic and anti-inflammatory activities were evaluated by a PTZ-induced convulsion model, AITC-induced hyperalgesia and AITC-induced paw edema, respectively. All studied esters, as well as their parent terpenes, were found to produce antinociceptive effects in the AITC-induced model and attenuate acute pain more than the reference drug benzocaine after their topical application. GABA esters of l-menthol and thymol were also shown to exceed the reference drug ibuprofen in their ability to decrease the inflammatory state induced by intraplantar injection of the TRPA1 activator AITC. The present findings indicate that GABA esters of carvacrol and guaiacol are not a classical prodrug and possess their own pharmacological activity. Prolonged antiseizure action of the ester based on the amino acid and guaiacol (200 mg/kg) was revealed at 24 h after oral administration. Furthermore, orally co-administered gidazepam (1 mg/kg) and GABA esters of l-menthol, thymol and carvacrol produce synergistic seizure prevention effects. PMID:27304960

  1. Synthesis and Pharmacological Properties of Novel Esters Based on Monocyclic Terpenes and GABA

    Directory of Open Access Journals (Sweden)

    Mariia Nesterkina

    2016-06-01

    Full Text Available Novel esters of γ-aminobutyric acid (GABA with monocyclic terpenes were synthesized via Steglich esterification and characterized by 1H-NMR, IR and mass spectral studies. Their anticonvulsant, analgesic and anti-inflammatory activities were evaluated by a PTZ-induced convulsion model, AITC-induced hyperalgesia and AITC-induced paw edema, respectively. All studied esters, as well as their parent terpenes, were found to produce antinociceptive effects in the AITC-induced model and attenuate acute pain more than the reference drug benzocaine after their topical application. GABA esters of l-menthol and thymol were also shown to exceed the reference drug ibuprofen in their ability to decrease the inflammatory state induced by intraplantar injection of the TRPA1 activator AITC. The present findings indicate that GABA esters of carvacrol and guaiacol are not a classical prodrug and possess their own pharmacological activity. Prolonged antiseizure action of the ester based on the amino acid and guaiacol (200 mg/kg was revealed at 24 h after oral administration. Furthermore, orally co-administered gidazepam (1 mg/kg and GABA esters of l-menthol, thymol and carvacrol produce synergistic seizure prevention effects.

  2. Novel 1-hydroxyazole bioisosteres of glutamic acid. Synthesis, protolytic properties, and pharmacology

    DEFF Research Database (Denmark)

    Stensbøl, Tine B; Uhlmann, Peter; Morel, Sandrine

    2002-01-01

    A number of 1-hydroxyazole derivatives were synthesized as bioisosteres of (S)-glutamic acid (Glu) and as analogues of the AMPA receptor agonist (R,S)-2-amino-3-(3-hydroxy-5-methyl-4-isoxazolyl)propionic acid (AMPA, 3b). All compounds were subjected to in vitro pharmacological studies, including...... the corresponding 4-methyl analogue 8b was a potent AMPA receptor agonist (EC(50) = 15 +/- 2 microM). In accordance with this disparity, compound 8a was found to inhibit synaptosomal [3H]D-aspartic acid uptake (IC(50) = 93 +/- 25 microM), as well as excitatory amino acid transporters (EAATs) EAAT1 (IC(50) = 100...... +/- 30 microM) and EAAT2 (IC(50) = 300 +/- 80 microM). By contrast, compound 8b showed no appreciable affinity for Glu uptake sites, neither synaptosomal nor cloned. Compounds 9a-c and 10a,b, possessing 1-hydroxyimidazole as the terminal acidic function, were devoid of activity in all of the systems...

  3. Bidens pilosa L. (Asteraceae: Botanical Properties, Traditional Uses, Phytochemistry, and Pharmacology

    Directory of Open Access Journals (Sweden)

    Arlene P. Bartolome

    2013-01-01

    Full Text Available There are 230 to 240 known Bidens species. Among them, Bidens pilosa is a representative perennial herb, globally distributed across temperate and tropical regions. B. pilosa has been traditionally used in foods and medicines without obvious adverse effects. Despite significant progress in phytochemical and biological analyses of B. pilosa over the past few years, comprehensive and critical reviews of this plant are anachronistic or relatively limited in scope. The present review aims to summarize up-to-date information on the phytochemistry, pharmacology, and toxicology of B. pilosa from the literature. In addition to botanical studies and records of the traditional use of B. pilosa in over 40 diseases, scientific studies investigating the potential medicinal uses of this species and its constituent phytochemicals for a variety of disorders are presented and discussed. The structure, bioactivity, and likely mechanisms of action of B. pilosa and its phytochemicals are emphasized. Although some progress has been made, further rigorous efforts are required to investigate the individual compounds isolated from B. pilosa to understand and validate its traditional uses and develop clinical applications. The present review provides preliminary information and gives guidance for further basic and clinical research into this plant.

  4. Review of Ethnomedicinal Uses, Phytochemistry and Pharmacological Properties of Euclea natalensis A.DC.

    Science.gov (United States)

    Maroyi, Alfred

    2017-12-02

    Euclea natalensis is traditionally used as herbal medicine for several human diseases and ailments in tropical Africa. This study reviews information on ethnomedicinal uses, botany, phytochemical constituents, pharmacology and toxicity of E. natalensis . Results of this study are based on literature search from several sources including electronic databases, books, book chapters, websites, theses and conference proceedings. This study showed that E. natalensis is used as traditional medicine in 57.1% of the countries where it is indigenous. Euclea natalensis has a high degree of consensus on abdominal pains, antidote for snake bites, diabetes, diarrhoea, malaria, roundworms, stomach problems, toothache, venereal diseases and wounds. Several ethnopharmacological studies have shown that crude extracts and chemical compounds from E. natalensis demonstrated many biological activities both in vitro and in vivo, which included antibacterial, antidiabetic, antifungal, antimycobacterial, antiviral, antioxidant, antiplasmodial, larvicidal, antischistosomal, molluscicidal, dentin permeability and hepatoprotective activities. Future studies should focus on the mechanism of biological activities of both crude extracts and chemical compounds from the species, as well as structure-function relationships of bioactive constituents of the species.

  5. RF-amide neuropeptides and their receptors in Mammals: Pharmacological properties, drug development and main physiological functions.

    Science.gov (United States)

    Quillet, Raphaëlle; Ayachi, Safia; Bihel, Frédéric; Elhabazi, Khadija; Ilien, Brigitte; Simonin, Frédéric

    2016-04-01

    RF-amide neuropeptides, with their typical Arg-Phe-NH2 signature at their carboxyl C-termini, belong to a lineage of peptides that spans almost the entire life tree. Throughout evolution, RF-amide peptides and their receptors preserved fundamental roles in reproduction and feeding, both in Vertebrates and Invertebrates. The scope of this review is to summarize the current knowledge on the RF-amide systems in Mammals from historical aspects to therapeutic opportunities. Taking advantage of the most recent findings in the field, special focus will be given on molecular and pharmacological properties of RF-amide peptides and their receptors as well as on their implication in the control of different physiological functions including feeding, reproduction and pain. Recent progress on the development of drugs that target RF-amide receptors will also be addressed. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. Systematic review of clinical trials assessing pharmacological properties of Salvia species on memory, cognitive impairment and Alzheimer's disease.

    Science.gov (United States)

    Miroddi, Marco; Navarra, Michele; Quattropani, Maria C; Calapai, Fabrizio; Gangemi, Sebastiano; Calapai, Gioacchino

    2014-06-01

    Salvia officinalis L. and Salvia lavandulaefolia L. have a longstanding use as traditional herbal remedies that can enhance memory and improve cognitive functions. Pharmacological actions of S. officinalis and S. lavandulaefolia on healthy subjects and on patients suffering of cognitive decline have been investigated. Aim of this review was to summarize published clinical trials assessing effectiveness and safety of S. officinalis and S. lavandulaefolia in the enhancement of cognitive performance in healthy subjects and neurodegenerative illnesses. Furthermore, to purchase a more complete view on safety of S. officinalis and S. lavandulaefolia, we collected and discussed articles regarding toxicity and adverse reactions. Eight clinical studies investigating on acute effects of S. officinalis on healthy subjects were included in the review. Six studies investigated on the effects of S. officinalis and S. lavandaeluaefolia on cognitive performance in healthy subjects. The two remaining were carried out to study the effects of sage on Azheimer's disease. Our review shows that S. officinalis and S. lavandulaefolia exert beneficial effects by enhancing cognitive performance both in healthy subjects and patients with dementia or cognitive impairment and is safe for this indication. Unfortunately, promising beneficial effects are debased by methodological issues, use of different herbal preparations (extracts, essential oil, use of raw material), lack of details on herbal products used. We believe that sage promising effects need further higher methodological standard clinical trials. © 2014 John Wiley & Sons Ltd.

  7. Pharmacological properties of S1RA, a new sigma-1 receptor antagonist that inhibits neuropathic pain and activity-induced spinal sensitization.

    Science.gov (United States)

    Romero, L; Zamanillo, D; Nadal, X; Sánchez-Arroyos, R; Rivera-Arconada, I; Dordal, A; Montero, A; Muro, A; Bura, A; Segalés, C; Laloya, M; Hernández, E; Portillo-Salido, E; Escriche, M; Codony, X; Encina, G; Burgueño, J; Merlos, M; Baeyens, J M; Giraldo, J; López-García, J A; Maldonado, R; Plata-Salamán, C R; Vela, J M

    2012-08-01

    The sigma-1 (σ(1) ) receptor is a ligand-regulated molecular chaperone that has been involved in pain, but there is limited understanding of the actions associated with its pharmacological modulation. Indeed, the selectivity and pharmacological properties of σ(1) receptor ligands used as pharmacological tools are unclear and the demonstration that σ(1) receptor antagonists have efficacy in reversing central sensitization-related pain sensitivity is still missing. The pharmacological properties of a novel σ(1) receptor antagonist (S1RA) were first characterized. S1RA was then used to investigate the effect of pharmacological antagonism of σ(1) receptors on in vivo nociception in sensitizing conditions and on in vitro spinal cord sensitization in mice. Drug levels and autoradiographic, ex vivo binding for σ(1) receptor occupancy were measured to substantiate behavioural data. Formalin-induced nociception (both phases), capsaicin-induced mechanical hypersensitivity and sciatic nerve injury-induced mechanical and thermal hypersensitivity were dose-dependently inhibited by systemic administration of S1RA. Occupancy of σ(1) receptors in the CNS was significantly correlated with the antinociceptive effects. No pharmacodynamic tolerance to the antiallodynic and antihyperalgesic effect developed following repeated administration of S1RA to nerve-injured mice. As a mechanistic correlate, electrophysiological recordings demonstrated that pharmacological antagonism of σ(1) receptors attenuated the wind-up responses in spinal cords sensitized by repetitive nociceptive stimulation. These findings contribute to evidence identifying the σ(1) receptor as a modulator of activity-induced spinal sensitization and pain hypersensitivity, and suggest σ(1) receptor antagonists as potential novel treatments for neuropathic pain. © 2012 The Authors. British Journal of Pharmacology © 2012 The British Pharmacological Society.

  8. Curriculum Guidelines for Pharmacology.

    Science.gov (United States)

    Shaw, David H.; And Others

    1990-01-01

    Pharmacology embraces the physical and chemical properties of drugs; the preparation of pharmaceutical agents; the absorption, fate, and excretion of drugs; and the effects of drugs on living systems. These guidelines represent a consensus on what would constitute a minimally acceptable pharmacology course for predoctoral dental students. (MLW)

  9. Enhanced thermophysical properties via PAO superstructure

    National Research Council Canada - National Science Library

    Pournorouz, Zahra; Mostafavi, Amirhossein; Pinto, Aditya; Bokka, Apparao; Jeon, Junha; Shin, Donghyun

    2017-01-01

    .... However, such enhancement in specific heat was only observed for molten salts, yet other engineering fluids such as water, ethylene glycol, and oil have shown a decrease of specific heat with doped nanoparticle...

  10. Synthesis and preliminary evaluation of pharmacological properties of some piperazine derivatives of xanthone.

    Science.gov (United States)

    Szkaradek, Natalia; Rapacz, Anna; Pytka, Karolina; Filipek, Barbara; Siwek, Agata; Cegła, Marek; Marona, Henryk

    2013-01-15

    A series of 9 piperazine derivatives of xanthone were synthesized and evaluated for cardiovascular activity. The following pharmacological experiments were conducted: the binding affinity for adrenoceptors, the influence on the normal electrocardiogram, the effect on the arterial blood pressure and prophylactic antiarrhythmic activity in adrenaline induced model of arrhythmia (rats, iv). Three compounds revealed nanomolar affinity for α(1)-adrenoceptor which was correlated with the strongest cardiovascular (antiarrhythmic and hypotensive) activity in animals' models. The most promising compound was 4-(3-(4-(2-methoxyphenyl)piperazine-1-yl)propoxy)-9H-xanthen-9-one hydrochloride (12) which revealed antiarrhythmic activity with ED(50) value of 0.69 mg/kg in adrenaline induced arrhythmia (rats, iv). Other synthesized xanthone derivatives, that is, (R,S)-4-(2-hydroxy-3-(4-(2-methoxyphenyl)piperazine-1-yl)propoxy)-9H-xanthen-9-one hydrochloride (10) and (R,S)-4-(2-acetoxy-3-(4-(2-methoxyphenyl)piperazine-1-yl)propoxy)-9H-xanthen-9-one hydrochloride (11) also acted as potential antiarrhythmics in adrenaline induced model of arrhythmia in rats after intravenous injection (ED(50) = 0.88 mg/kg and 0.89 mg/kg, respectively). These values were lower than values obtained for reference drugs such as propranolol and urapidil, but not carvedilol. Results were quite promising and suggested that in the group of xanthone derivatives new potential antiarrhythmics and hypotensives might be found. Copyright © 2012 Elsevier Ltd. All rights reserved.

  11. Biochemical properties and comparative pharmacology of a coagulant from Deinagkistrodon acutus snake venom.

    Science.gov (United States)

    Tang, Song-Shan; Wang, Xiao-Hua; Zhang, Juan-Hui; Tang, Bo-Shan; Qian, Li; Li, Pei-Ying; Luo, Lie-Wei

    2013-04-11

    A number of snake venom thrombin-like enzymes (TLEs) have already been characterized. Some TLEs play significant roles in vessel injury hemostasis. A novel TLE (Agacutase) was purified from Deinagkistrodon acutus snake venom by the means of Sephadex G-75, DEAE-Sepharose FF, and Sephadex G-25 column chromatography. Structural analysis indicated that Agacutase is a single-chain glycoprotein with a molecular mass of 31,084 Da, isoelectric point of 4.38, optimal activity at 37 °C and pH 6.6, sugar content of 7.6%. Its N-terminal 44 amino acid sequence was determined to be VIGGNECDTNEHRFLAAFFTSRPWIFQCAGTLIHEEWVLAAAHC, showing maximum identity of 80% with that of Dav-X protease. The Agacutase-induced clotting activity was not influenced by heparin, hirudin, or Dextran 40, but activated by Ca(2+) and inhibited by PMSF or lactose, which suggests that Agacutase is a serine protease and the coagulation activity is independent of Thrombin. Agacutase with arginine esterase activity specifically cleaves the α-chain of fibrinogen. Agacutase iv (0.03-0.12 U/kg) shortened 16-68% of the rabbit blood clotting time. No significant influence was indicated on platelet, Factor II and XIII, or fibrinolytic system. It converts fibrinogen into the soluble fibrin that accelerates hemostasis at wound. Pharmacological comparison showed the hemostatic effect of Agacutase lasted 24h while Reptilase did 8h. Its maximum tolerated, abnormal toxicity, allergic, and hemorrhagin doses were 80 U/kg, 1 U, 2 U, and 50 U, respectively, whereas those of Reptilase or Agacutin were 35 U/kg, 0.25 U, 0.25 U, and 0.2 U, respectively. The results indicated that Agacutase may be a predominant coagulant. Copyright © 2013 Elsevier B.V. All rights reserved.

  12. Robust resilience and substantial interest: a survey of pharmacological cognitive enhancement among university students in the UK and Ireland.

    Directory of Open Access Journals (Sweden)

    Ilina Singh

    Full Text Available Use of 'smart drugs' among UK students is described in frequent media reports as a rapidly increasing phenomenon. This article reports findings from the first large-scale survey of pharmacological cognitive enhancement (PCE among students in the UK and Ireland. Conducted from February to September 2012, a survey of a convenience sample of 877 students measured PCE prevalence, attitudes, sources, purposes and ethics. Descriptive and logistic regression statistical methods were used to analyse the data. Lifetime prevalence of PCE using modafinil, methylphenidate or Adderall was under 10%, while past regular and current PCE users of these substances made up between 0.3%-4% of the survey population. A substantial majority of students was unaware of and/or uninterested in PCE; however about one third of students were interested in PCE. PCE users were more likely to be male, British and older students; predictors of PCE use included awareness of other students using PCEs, ADHD symptomatology, ethical concerns, and alcohol and cannabis use. The survey addresses the need for better evidence about PCE prevalence and practices among university students in the UK. We recommend PCE-related strategies for universities based on the survey findings.

  13. Robust resilience and substantial interest: a survey of pharmacological cognitive enhancement among university students in the UK and Ireland.

    Science.gov (United States)

    Singh, Ilina; Bard, Imre; Jackson, Jonathan

    2014-01-01

    Use of 'smart drugs' among UK students is described in frequent media reports as a rapidly increasing phenomenon. This article reports findings from the first large-scale survey of pharmacological cognitive enhancement (PCE) among students in the UK and Ireland. Conducted from February to September 2012, a survey of a convenience sample of 877 students measured PCE prevalence, attitudes, sources, purposes and ethics. Descriptive and logistic regression statistical methods were used to analyse the data. Lifetime prevalence of PCE using modafinil, methylphenidate or Adderall was under 10%, while past regular and current PCE users of these substances made up between 0.3%-4% of the survey population. A substantial majority of students was unaware of and/or uninterested in PCE; however about one third of students were interested in PCE. PCE users were more likely to be male, British and older students; predictors of PCE use included awareness of other students using PCEs, ADHD symptomatology, ethical concerns, and alcohol and cannabis use. The survey addresses the need for better evidence about PCE prevalence and practices among university students in the UK. We recommend PCE-related strategies for universities based on the survey findings.

  14. U.S. Army Research on Pharmacological Enhancement of Soldier Performance: Stimulants, Anabolic Hormones, and Blood Doping.

    Science.gov (United States)

    Friedl, Karl E

    2015-11-01

    The level playing field of competitive sports is an irrelevant concern in asymmetrical warfare. However, there is a common theme of pressure to use performance-enhancing drugs because athletic or military opponents may be using them to advantage. This interest is fueled by personal anecdotes, misconceptions, and myths, and decisions to use or not to use pharmacological interventions may ignore available scientific data. The U.S. Army has led research in this area, with an abundance of published data extending back to World War II. Behavioral effects have been a consistent concern. A key conclusion to be drawn from this research is that although there may be specialized applications for some of these interventions, the majority of soldiers will gain the greatest performance benefits from effective physical and mental training programs combined with good principles of rest and nutrition. Furthermore, the perceived need to improve human biology with drugs may be solving the wrong problem, trying to fit the human to the demands of poorly conceived tactics, tasks, and equipments instead of capitalizing on human capabilities.

  15. The abuse of diuretics as performance-enhancing drugs and masking agents in sport doping: pharmacology, toxicology and analysis.

    Science.gov (United States)

    Cadwallader, Amy B; de la Torre, Xavier; Tieri, Alessandra; Botrè, Francesco

    2010-09-01

    Diuretics are drugs that increase the rate of urine flow and sodium excretion to adjust the volume and composition of body fluids. There are several major categories of this drug class and the compounds vary greatly in structure, physicochemical properties, effects on urinary composition and renal haemodynamics, and site and mechanism of action. Diuretics are often abused by athletes to excrete water for rapid weight loss and to mask the presence of other banned substances. Because of their abuse by athletes, diuretics have been included on The World Anti-Doping Agency's (WADA) list of prohibited substances; the use of diuretics is banned both in competition and out of competition and diuretics are routinely screened for by anti-doping laboratories. This review provides an overview of the pharmacology and toxicology of diuretics and discusses their application in sports. The most common analytical strategies currently followed by the anti-doping laboratories accredited by the WADA are discussed along with the challenges laboratories face for the analysis of this diverse class of drugs.

  16. Enhanced thermophysical properties via PAO superstructure

    Science.gov (United States)

    Pournorouz, Zahra; Mostafavi, Amirhossein; Pinto, Aditya; Bokka, Apparao; Jeon, Junha; Shin, Donghyun

    2017-01-01

    For the last few years, molten salt nanomaterials have attracted many scientists for their enhanced specific heat by doping a minute concentration of nanoparticles (up to 1% by weight). Likewise, enhancing the specific heat of liquid media is important in many aspects of engineering such as engine oil, coolant, and lubricant. However, such enhancement in specific heat was only observed for molten salts, yet other engineering fluids such as water, ethylene glycol, and oil have shown a decrease of specific heat with doped nanoparticles. Recent studies have shown that the observed specific heat enhancement resulted from unique nanostructures that were formed by molten salt molecules when interacting with nanoparticles. Thus, such enhancement in specific heat is only possible for molten salts because other fluids may not naturally form such nanostructures. In this study, we hypothesized such nanostructures can be mimicked through in situ formation of fabricated nano-additives, which are putative nanoparticles coated with useful organic materials (e.g., polar-group-ended organic molecules) leading to superstructures, and thus can be directly used for other engineering fluids. We first applied this approach to polyalphaolefin (PAO). A differential scanning calorimeter (DSC), a rheometer, and a customized setup were employed to characterize the heat capacity, viscosity, and thermal conductivity of PAO and PAO with fabricated nano-additives. Results showed 44.5% enhanced heat capacity and 19.8 and 22.98% enhancement for thermal conductivity and viscosity, respectively, by an addition of only 2% of fabricated nanostructures in comparison with pure PAO. Moreover, a partial melting of the polar-group-ended organic molecules was observed in the first thermal cycle and the peak disappeared in the following cycles. This indicates that the in situ formation of fabricated nano-additives spontaneously occurs in the thermal cycle to form nanostructures. Figure of merit analyses have

  17. Pharmacologically active microcarriers delivering BDNF within a hydrogel: Novel strategy for human bone marrow-derived stem cells neural/neuronal differentiation guidance and therapeutic secretome enhancement.

    Science.gov (United States)

    Kandalam, Saikrishna; Sindji, Laurence; Delcroix, Gaëtan J-R; Violet, Fabien; Garric, Xavier; André, Emilie M; Schiller, Paul C; Venier-Julienne, Marie-Claire; des Rieux, Anne; Guicheux, Jérôme; Montero-Menei, Claudia N

    2017-02-01

    Stem cells combined with biodegradable injectable scaffolds releasing growth factors hold great promises in regenerative medicine, particularly in the treatment of neurological disorders. We here integrated human marrow-isolated adult multilineage-inducible (MIAMI) stem cells and pharmacologically active microcarriers (PAMs) into an injectable non-toxic silanized-hydroxypropyl methylcellulose (Si-HPMC) hydrogel. The goal is to obtain an injectable non-toxic cell and growth factor delivery device. It should direct the survival and/or neuronal differentiation of the grafted cells, to safely transplant them in the central nervous system, and enhance their tissue repair properties. A model protein was used to optimize the nanoprecipitation conditions of the neuroprotective brain-derived neurotrophic factor (BDNF). BDNF nanoprecipitate was encapsulated in fibronectin-coated (FN) PAMs and the in vitro release profile evaluated. It showed a prolonged, bi-phasic, release of bioactive BDNF, without burst effect. We demonstrated that PAMs and the Si-HPMC hydrogel increased the expression of neural/neuronal differentiation markers of MIAMI cells after 1week. Moreover, the 3D environment (PAMs or hydrogel) increased MIAMI cells secretion of growth factors (b-NGF, SCF, HGF, LIF, PlGF-1, SDF-1α, VEGF-A & D) and chemokines (MIP-1α & β, RANTES, IL-8). These results show that PAMs delivering BDNF combined with Si-HPMC hydrogel represent a useful novel local delivery tool in the context of neurological disorders. It not only provides neuroprotective BDNF but also bone marrow-derived stem cells that benefit from that environment by displaying neural commitment and an improved neuroprotective/reparative secretome. It provides preliminary evidence of a promising pro-angiogenic, neuroprotective and axonal growth-promoting device for the nervous system. Combinatorial tissue engineering strategies for the central nervous system are scarce. We developed and characterized a novel

  18. [Isolation and pharmacological properties of analgesic fraction from venom of Naja Naja atra].

    Science.gov (United States)

    Liang, Ying-Xia; Han, Li-Ping; Jiang, Wei-Jian; Zhao, Shu-Jin

    2009-07-01

    To separate main analgesic fraction from venom of Guangdong Naja naja atra, to establish the basis for the using of Naja naja atra and find new analgesic fraction. Affinity chromatography and size exclusion were used to isolate the analgesic fraction from the venom of Naja naja atra, and then to determine its properties by biochemical methods, such as SDS-polyacryamide gel electrophoresis ( SDS-PAGE), HPLC and Mole-toff. HPLC showed its relative purity was 95% (HPLC)and Mw was 6741. 236 Da. We observed that peripheral administration of neurotoxin strongly reduced the mechanical allogynia and thermal hyperalgesia for 24 hours, associated with this neuropathy (L5 spinal nerve ligation). The fraction from venom of Naja naja atra has significant analgesic effect and it is worth further developing.

  19. Umeclidinium for treating COPD: an evaluation of pharmacologic properties, safety and clinical use.

    Science.gov (United States)

    Manickam, Rajapriya; Asija, Amit; Aronow, Wilbert S

    2014-11-01

    Umeclidinium (UMEC) is a long-acting inhaled antagonist of muscarinic cholinergic receptors. The FDA approved UMEC for maintenance treatment of chronic obstructive pulmonary disease (COPD) in 2013 and it became available for commercial use as a single agent in 2014. After tiotropium, this is the only other once daily LAMA available for COPD patients. In this article, we have comprehensively reviewed the pharmacokinetic properties and analyzed the currently available randomized controlled trials on the efficacy and safety profile of UMEC. We have discussed the current clinical application of UMEC and its future implication. UMEC is the newer long-acting antimuscarinic agent (LAMA) that has demonstrated significant improvement in lung function and improved the quality of life in moderate-to-severe COPD patients. It is suitable for once daily dosing, has low anticholinergic side effects and is well tolerated. Overall, it is a safe, effective and convenient LAMA for maintenance therapy in COPD patients.

  20. Pharmacological evaluation of anxiolytic property of aqueous root extract of Cymbopogon citratus in mice

    Directory of Open Access Journals (Sweden)

    David Arome

    2014-01-01

    Full Text Available Aim: This study was designed to evaluate the anxiolytic property of aqueous root extract of Cymbopogon citratus in mice. Materials and Methods: In this study, stress induced hyperthermia (SIH, elevated plus maze (EPM and open field experimental models were employed. Results: In SIH model, the extract caused a significant (P 0.05 effect. In open field model, 200 mg/kg and 600 mg/kg extract doses significantly (P < 0.05 increased locomotion of the mice more than the standard, while rearing and defecation were less in the extract groups. Conclusion: In different experimental models used significant anxiolytic effect was observed of the aqueous extract at different dose levels in comparison to reference standard and normal saline group. This clearly justified its folkloric application in the treatment of anxiety disorders.

  1. Pharmacological properties and related constituents of stem bark of Pterocarpus erinaceus Poir. (Fabaceae).

    Science.gov (United States)

    Noufou, Ouédraogo; Wamtinga, Sawadogo Richard; André, Tibiri; Christine, Bayet; Marius, Lompo; Emmanuelle, Hay A; Jean, Koudou; Marie-Geneviève, Dijoux; Pierre, Guissou Innocent

    2012-01-01

    To screen methanol and dichloromethane extracts of stem bark of Pterocarpus erinaceus for anti-inflammatory, analgesic, in vitro antioxidant activities and phytochemical analysis. Anti-inflammatory activity was determined by using carrageenan induced-edema of mice paw and croton oil-induced edema of mice ear; analgesic effect was evaluated using acetic acid-induced writhing. Phytochemical screening of extracts was performed by thin layer chromatography. The chromatographic fractionation led to the isolation of main active components as friedelin, lupeol and epicathechin. The structures were established by TLC and nuclear magnetic resonance studies. Both methanol and dichloromethane extracts, friedelin, lupeol and epicatechin showed a significant anti-inflammatory effect using croton oil induced-ear edema. Furthermore, the action of dichloromethane extract was more important. At the doses of 100 and 200 mg/kg, the methanol extract was able to reduce the carrageenan induced-hind paw edema, while at the doses of 100, 200 and 400 mg/kg, it showed an important analgesic effect against writhing induced by acetic acid injection of 38.8%, 68.0% and 74.3%, respectively. Antioxidative properties of methanol extract and its dichloromethane and ethyl acetate fractions were assessed by using the 1,1-diphenyl-2-picrylhydrazyl method. The methanol extract showed the stronger radical scavenging activity than dichloromethane and ethyl acetate fractions, with an antiradical power of 5, 3.5 and 2 respectively. The main components isolated from these extracts as friedelin, lupeol and epicathechin were responsible of these activities. The results suggest that the stem bark extracts of Pterocarpus erinaceus possessed important anti-inflammatory, analgesic activities and strong antioxidant properties, therefore, they could be used as potential natural ingredients in the pharmaceutical industry. Copyright © 2012 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  2. Pharmacological properties of Myrtacine® and its potential value in acne treatment.

    Science.gov (United States)

    Fiorini-Puybaret, Christel; Aries, Marie-Françoise; Fabre, Bernard; Mamatas, Stelianos; Luc, Joëlle; Degouy, Arnaud; Ambonati, Marco; Mejean, Carine; Poli, Florence

    2011-09-01

    This study aimed at evaluating the antiproliferative, antibacterial, and anti-inflammatory properties of an ethanolic myrtle extract (Myrtacine®) in vitro, characterising its potential active compounds (myrtucommulones A and B') by structural analysis, and evaluating their biological activity. Antiproliferative activity was assessed by the BrdU incorporation assay in HaCat keratinocytes and inhibitory and bactericidal activities against P. ACNES strains by measuring the minimal inhibitory concentration (MIC) and D value. Anti-inflammatory effect was evaluated by measuring 6-keto-prostaglandin F1 α and [³H]-arachidonic acid metabolite production in keratinocytes stimulated for inflammation. Myrtacine® inhibited keratinocyte proliferation by 27 % and 76 % at 1 and 3 µg/mL, respectively (p P. ACNES strains growth with MICs of 4.9 µg/mL and 2.4 µg/mL, respectively. Myrtucommulone B' and myrtucommulone A displayed a similar inhibitory activity against both strains (for both strains, MIC = 1.2 µg/mL and about 0.5 µg/mL, respectively). At 3 and 10 µg/mL, Myrtacine® significantly decreased all metabolite production from cyclooxygenase (81 % and 107 %, p lipase activity at 100 µg/mL and 1 mg/mL, as it decreased lipase activity by respectively 53 % and 100 % (p acne lesions. © Georg Thieme Verlag KG Stuttgart · New York.

  3. Antiadherent and Antibiofilm Activity of Humulus lupulus L. Derived Products: New Pharmacological Properties

    Directory of Open Access Journals (Sweden)

    Marcin Rozalski

    2013-01-01

    Full Text Available New antimicrobial properties of products derived from Humulus lupulus L. such as antiadherent and antibiofilm activities were evaluated. The growth of gram-positive but not gram-negative bacteria was inhibited to different extents by these compounds. An extract of hop cones containing 51% xanthohumol was slightly less active against S. aureus strains (MIC range 31.2–125.0 μg/mL than pure xanthohumol (MIC range 15.6–62.5 μg/mL. The spent hop extract, free of xanthohumol, exhibited lower but still relevant activity (MIC range 1-2 mg/mL. There were positive coactions of hop cone, spent hop extracts, and xanthohumol with oxacillin against MSSA and with linezolid against MSSA and MRSA. Plant compounds in the culture medium at sub-MIC concentrations decreased the adhesion of Staphylococci to abiotic surfaces, which in turn caused inhibition of biofilm formation. The rate of mature biofilm eradication by these products was significant. The spent hop extract at MIC reduced biofilm viability by 42.8%, the hop cone extract by 74.8%, and pure xanthohumol by 86.5%. When the hop cone extract or xanthohumol concentration was increased, almost complete biofilm eradication was achieved (97–99%. This study reveals the potent antibiofilm activity of hop-derived compounds for the first time.

  4. Are the Traditional Medical Uses of Muricidae Molluscs Substantiated by Their Pharmacological Properties and Bioactive Compounds?

    Directory of Open Access Journals (Sweden)

    Kirsten Benkendorff

    2015-08-01

    Full Text Available Marine molluscs from the family Muricidae hold great potential for development as a source of therapeutically useful compounds. Traditionally known for the production of the ancient dye Tyrian purple, these molluscs also form the basis of some rare traditional medicines that have been used for thousands of years. Whilst these traditional and alternative medicines have not been chemically analysed or tested for efficacy in controlled clinical trials, a significant amount of independent research has documented the biological activity of extracts and compounds from these snails. In particular, Muricidae produce a suite of brominated indoles with anti-inflammatory, anti-cancer and steroidogenic activity, as well as choline esters with muscle-relaxing and pain relieving properties. These compounds could explain some of the traditional uses in wound healing, stomach pain and menstrual problems. However, the principle source of bioactive compounds is from the hypobranchial gland, whilst the shell and operculum are the main source used in most traditional remedies. Thus further research is required to understand this discrepancy and to optimise a quality controlled natural medicine from Muricidae.

  5. Effects of drug pharmacokinetic/pharmacodynamic properties, characteristics of medication use, and relevant pharmacological interventions on fall risk in elderly patients.

    Science.gov (United States)

    Chen, Ying; Zhu, Ling-Ling; Zhou, Quan

    2014-01-01

    Falls among the elderly are an issue internationally and a public health problem that brings substantial economic and quality-of-life burdens to individuals and society. Falls prevention is an important measure of nursing quality and patient safety. Numerous studies have evaluated the association of medication use with fall risk in elderly patients. However, an up-to-date review has not been available to summarize the multifaceted pharmaceutical concerns in the prevention of medication-related falls. Relevant literature was identified by performing searches in PubMed, Web of Science, and the Cochrane Library, covering the period until February 2014. We included studies that described an association between medications and falls, and effects of drug pharmacokinetic/pharmacodynamic properties, characteristics of medication use, and pharmacological interventions on fall risk in elderly patients. The full text of each included article was critically reviewed, and data interpretation was performed. Fall-risk-increasing drugs (FRIDs) include central nervous system-acting agents, cough preparations, nonsteroidal anti-inflammatory drugs, anti-Alzheimer's agents, antiplatelet agents, calcium antagonists, diuretics, α-blockers, digoxin, hypoglycemic drugs, neurotoxic chemotherapeutic agents, nasal preparations, and antiglaucoma ophthalmic preparations. The degree of medication-related fall risk was dependent on one or some of the following factors: drug pharmacokinetic/pharmacodynamic properties (eg, elimination half-life, metabolic pathway, genetic polymorphism, risk rating of medications despite belonging to the same therapeutic class) and/or characteristics of medication use (eg, number of medications and drug-drug interactions, dose strength, duration of medication use and time since stopping, medication change, prescribing appropriateness, and medication adherence). Pharmacological interventions, including withdrawal of FRIDs, pharmacist-conducted clinical medication

  6. Luminescent oxide nanoparticles with enhanced optical properties

    Energy Technology Data Exchange (ETDEWEB)

    Mialon, Genevieve, E-mail: genevieve.mialon@polytechnique.ed [Laboratory of Condensed Matter Physics, Ecole Polytechnique, Palaiseau 91128 (France); Poggi, Melanie [Laboratory of Condensed Matter Physics, Ecole Polytechnique, Palaiseau 91128 (France); Casanova, Didier; Nguyen, Thanh-Liem; Tuerkcan, Silvan; Alexandrou, Antigoni [Laboratory of Optics and Biosciences, Ecole Polytechnique, Palaiseau 91128 (France); Gacoin, Thierry; Boilot, Jean-Pierre [Laboratory of Condensed Matter Physics, Ecole Polytechnique, Palaiseau 91128 (France)

    2009-12-15

    Yttrium vanadate particles doped with europium are studied for their applications as biomolecule labels. Two parts of our recent work are presented. The first concerns the thermal treatment of particles incorporated in a solid matrix. After annealing at 1000 deg. C and redispersion in water by dissolution of the matrix, the structural and optical properties are greatly improved without any modification of size; the obtained nanoparticles appear as perfect single crystals of 39 nm and have the same emission properties as the bulk material. Their quantum yield is worth 39% for 5% europium doping and the emission lifetime is 1 ms. The second aspect concerns the functionalization of the nanoparticles by the sol-gel condensation of aminopropyltriethoxysilane at the surface of particles. The chemical accessibility of amino groups grafted on the particles is measured by reaction with an organic fluorescent tag fluorescein isothiocyanate (FITC). These amine-coated nanoparticles were coupled to a peptidic toxin via a cross linker and allowed observation of the toxin motion bound to its membrane receptor.

  7. Enhancements in Magnesium Die Casting Impact Properties

    Energy Technology Data Exchange (ETDEWEB)

    David Schwam; John F. Wallace; Yulong Zhu; Srinath Viswanathan; Shafik Iskander

    2000-06-30

    The need to produce lighter components in transportation equipment is the main driver in the increasing demand for magnesium castings. In many automotive applications, components can be made of magnesium or aluminum. While being lighter, often times the magnesium parts have lower impact and fatigue properties than the aluminum. The main objective of this study was to identify potential improvements in the impact resistance of magnesium alloys. The most common magnesium alloys in automotive applications are AZ91D, AM50 and AM60. Accordingly, these alloys were selected as the main candidates for the study. Experimental quantities of these alloys were melted in an electrical furnace under a protective atmosphere comprising sulfur hexafluoride, carbon dioxide and dry air. The alloys were cast both in a permanent mold and in a UBE 315 Ton squeeze caster. Extensive evaluation of tensile, impact and fatigue properties was conducted at CWRU on permanent mold and squeeze cast test bars of AZ91, AM60 and AM50. Ultimate tensile strength values between 20ksi and 30ksi were obtained. The respective elongations varied between 25 and 115. the Charpy V-notch impact strength varied between 1.6 ft-lb and 5 ft-lb depending on the alloy and processing conditions. Preliminary bending fatigue evaluation indicates a fatigue limit of 11-12 ksi for AM50 and AM60. This is about 0.4 of the UTS, typical for these alloys. The microstructures of the cast specimens were investigated with optical and scanning electron microscopy. Concomitantly, a study of the fracture toughness in AM60 was conducted at ORNL as part of the study. The results are in line with values published in the literature and are representative of current state of the art in casting magnesium alloys. The experimental results confirm the strong relationship between aluminum content of the alloys and the mechanical properties, in particular the impact strength and the elongation. As the aluminum content increases from about 5

  8. Composite Materials with Magnetically Aligned Carbon Nanoparticles Having Enhanced Electrical Properties and Methods of Preparation

    Science.gov (United States)

    Hong, Haiping (Inventor); Peterson, G.P. (Bud) (Inventor); Salem, David R. (Inventor)

    2016-01-01

    Magnetically aligned carbon nanoparticle composites have enhanced electrical properties. The composites comprise carbon nanoparticles, a host material, magnetically sensitive nanoparticles and a surfactant. In addition to enhanced electrical properties, the composites can have enhanced mechanical and thermal properties.

  9. Harnessing the medicinal properties of Andrographis paniculata for diseases and beyond: a review of its phytochemistry and pharmacology

    Directory of Open Access Journals (Sweden)

    Agbonlahor Okhuarobo

    2014-06-01

    Full Text Available Andrographis paniculata Wall (family Acanthaceae is one of the most popular medicinal plants used traditionally for the treatment of array of diseases such as cancer, diabetes, high blood pressure, ulcer, leprosy, bronchitis, skin diseases, flatulence, colic, influenza, dysentery, dyspepsia and malaria for centuries in Asia, America and Africa continents. It possesses several photochemical constituents with unique and interesting biological properties. This review describes the past and present state of research on Andrographis paniculata with respect to the medicinal usage, phytochemistry, pharmacological activities, toxicity profile and therapeutic usage, in order to bridge the gap requiring future research opportunities. This review is based on literature study on scientific journals and books from library and electronic sources. Diterpenes, flavonoids, xanthones, noriridoides and other miscellaneous compounds have been isolated from the plant. Extract and pure compounds of the plant have been reported for their antimicrobial, cytotoxicity, anti-protozoan, anti-inflammatory, anti-oxidant, immunostimulant, anti-diabetic, anti-infective, anti-angiogenic, hepato-renal protective, sex hormone/sexual function modulation, liver enzymes modulation insecticidal and toxicity activities. The results of numerous toxicity evaluations of extracts and metabolites isolated from this plant did not show any significant acute toxicity in experimental animals. Detailed and more comprehensive toxicity profile on mammalian tissues and organs is needed in future studies.

  10. Feasibility assessment of using oxygen-enhanced magnetic resonance imaging for evaluating the effect of pharmacological treatment in COPD

    Energy Technology Data Exchange (ETDEWEB)

    Morgan, Alexandra R., E-mail: alex.morgan@bioxydyn.com [Bioxydyn Ltd, Manchester (United Kingdom); Centre for Imaging Sciences and Biomedical Imaging Institute, Manchester Academic Health Sciences Centre, University of Manchester, Manchester (United Kingdom); Parker, Geoff J.M.; Roberts, Caleb [Bioxydyn Ltd, Manchester (United Kingdom); Centre for Imaging Sciences and Biomedical Imaging Institute, Manchester Academic Health Sciences Centre, University of Manchester, Manchester (United Kingdom); Buonaccorsi, Giovanni A.; Maguire, Niall C. [Bioxydyn Ltd, Manchester (United Kingdom); Hubbard Cristinacce, Penny L. [Centre for Imaging Sciences and Biomedical Imaging Institute, Manchester Academic Health Sciences Centre, University of Manchester, Manchester (United Kingdom); Singh, Dave; Vestbo, Jørgen [University of Manchester, Medicines Evaluation Unit, Manchester Academic Health Sciences Centre, University Hospital of South Manchester, Manchester (United Kingdom); Bjermer, Leif [Department of Respiratory Medicine and Allergology, Skåne University Hospital, Lund (Sweden); Jögi, Jonas [Department of Clinical Physiology, Skåne University Hospital and Lund University, Lund (Sweden); Taib, Ziad; Sarv, Janeli; Bruijnzeel, Piet L.B.; Olsson, Lars E.; Bondesson, Eva [AstraZeneca R and D, Mölndal (Sweden); Nihlén, Ulf [Department of Respiratory Medicine and Allergology, Skåne University Hospital, Lund (Sweden); AstraZeneca R and D, Mölndal (Sweden); McGrath, Deirdre M. [Centre for Imaging Sciences and Biomedical Imaging Institute, Manchester Academic Health Sciences Centre, University of Manchester, Manchester (United Kingdom); Young, Simon S. [AstraZeneca R and D, Alderley Park (United Kingdom); and others

    2014-11-15

    Highlights: • We investigate physiologic response to standard COPD treatment regimes using OE-MRI. • We assess the potential role of OE-MRI in future drug development studies. • In COPD, OE-MRI parameters showed response to single-dose formoterol. • OE-MRI parameters showed response to 8-week formoterol/budesonide treatment. • OE-MRI measurements are feasible in a small-scale multi-center trial setting. - Abstract: Objectives: Oxygen-enhanced MRI (OE-MRI) biomarkers have potential value in assessment of COPD, but need further evaluation before treatment-induced changes can be interpreted. The objective was to evaluate how OE-MRI parameters of regional ventilation and oxygen uptake respond to standard pharmacological interventions in COPD, and how the response compares to that of gold standard pulmonary function tests. Materials and methods: COPD patients (n = 40), mean FEV{sub 1} 58% predicted normal, received single-dose inhaled formoterol 9 μg, or placebo, followed by 8 weeks treatment bid with a combination of budesonide and formoterol Turbuhaler{sup ®} 320/9 μg or formoterol Turbuhaler{sup ®}. OE-MRI biomarkers were obtained, as well as X-ray computed tomography (CT) biomarkers and pulmonary function tests, in a two-center study. An ANCOVA statistical model was used to assess effect size of intervention measurable in OE-MRI parameters of lung function. Results: OE-MRI data were successfully acquired at both study sites. 8-week treatment with budesonide/formoterol significantly decreased lung wash-out time by 31% (p < 0.01), decreased the change in lung oxygen level upon breathing pure oxygen by 13% (p < 0.05) and increased oxygen extraction from the lung by 58% (p < 0.01). Single-dose formoterol increased both lung wash-out time (+47%, p < 0.05) and lung oxygenation time (+47%, p < 0.05). FEV{sub 1} was improved by single-dose formoterol (+12%, p < 0.001) and 8 weeks of budesonide/formoterol (+ 18%, p < 0.001), consistent with published studies

  11. Hypocretin-1 receptors regulate the reinforcing and reward-enhancing effects of cocaine: Pharmacological and behavioral genetics evidence

    Directory of Open Access Journals (Sweden)

    Jonathan eHollander

    2012-07-01

    Full Text Available Considerable evidence suggests that transmission at hypocretin-1 (orexin-1 receptors (Hcrt-R1 plays an important role in the reinstatement of extinguished cocaine-seeking behaviors in rodents. However, far less is known about the role for hypocretin transmission in regulating ongoing cocaine-taking behavior. Here, we investigated the effects of the selective Hcrt-R1 antagonist SB-334867 on cocaine intake, as measured by intravenous (IV cocaine self-administration in rats. The stimulatory effects of cocaine on brain reward systems contribute to the establishment and maintenance of cocaine-taking behaviors. Therefore, we also assessed the effects of SB-334867 on the reward-enhancing properties of cocaine, as measured by cocaine-induced lowering of intracranial self-stimulation (ICSS thresholds. Finally, to definitively establish a role for Hcrt-R1 in regulating cocaine intake, we assessed IV cocaine self-administration in Hcrt-R1 knockout mice. We found that SB-334867 (1-4 mg/kg dose-dependently decreased cocaine (0.5 mg/kg/infusion self-administration in rats but did not alter responding for food rewards under the same schedule of reinforcement. This suggests that SB-334867 decreased cocaine reinforcement without negatively impacting operant performance. SB-334867 (1-4 mg/kg also dose-dependently attenuated the stimulatory effects of cocaine (10 mg/kg on brain reward systems, as measured by reversal of cocaine-induced lowering of ICSS thresholds in rats. Finally, we found that Hcrt-R1 knockout mice self-administered far less cocaine than wildtype mice across the entire dose-response function. These data demonstrate that Hcrt-R1 play an important role in regulating the reinforcing and reward-enhancing properties of cocaine, and suggest that hypocretin transmission is likely essential for establishing and maintaining the cocaine habit in human addicts.

  12. The pharmacology of TD-8954, a potent and selective 5-HT4 receptor agonist with gastrointestinal prokinetic properties

    Directory of Open Access Journals (Sweden)

    David T Beattie

    2011-05-01

    Full Text Available This study evaluated the in vitro and in vivo pharmacological properties of TD-8954, a potent and selective 5-HT4 receptor agonist. TD-8954 had high affinity (pKi = 9.4 for human recombinant 5-HT4(c (h5-HT4(c receptors, and selectivity (> 2,000-fold over all other 5-HT receptors and non-5-HT receptors, ion channels, enzymes and transporters tested (n = 78. TD-8954 produced an elevation of cAMP in HEK-293 cells expressing the h5-HT4(c receptor (pEC50 = 9.3, and contracted the guinea pig colonic longitudinal muscle/myenteric plexus (LMMP preparation (pEC50 = 8.6. TD-8954 had moderate intrinsic activity (IA in the in vitro assays. In conscious guinea pigs, subcutaneous (s.c. administration of TD 8954 (0.03 - 3 mg/kg increased the colonic transit of carmine red dye, reducing the time taken for its excretion. Following intraduodenal (i.d. dosing to anesthetized rats, TD 8954 (0.03 - 10 mg/kg evoked a dose-dependent relaxation of the esophagus. Following oral administration to conscious dogs, TD 8954 (10 and 30 µg/kg produced an increase in contractility of the antrum, duodenum and jejunum. In a single ascending oral dose study in healthy human subjects, TD-8954 (0.1 - 20 mg increased bowel movement frequency and reduced the time to first stool. It is concluded that TD-8954 is a potent and selective 5-HT4 receptor agonist in vitro, with robust in vivo stimulatory activity in the gastrointestinal (GI tract of guinea pigs, rats, dogs and humans. TD-8954 may have clinical utility in patients with disorders of reduced GI motility.

  13. Microwave Enhancement in Coronal Holes: Statistical Properties Ν ...

    Indian Academy of Sciences (India)

    tribpo

    Astr. (2000) 21, 413 417. Microwave Enhancement in Coronal Holes: Statistical Properties. Ν. Gopalswamy1,2*, Κ. Shibasaki3, & Μ. Salem4. 1. Bldg 26, Room Gl, Code 682.3, NASA/GSFC, Greenbelt MD, USA. 2 Center for Solar Physics and Space Weather, The Catholic University of America,. Washington DC 20064.

  14. Enhancement of nonlinear optical properties of compounds of silica ...

    Indian Academy of Sciences (India)

    The aim of this paper is to introduce a method for enhancing the nonlinear optical properties in silica glass by using metallic nanoparticles. First, the T-matrix method is developed to calculate the effective dielectric constant for the compound of silica glass and metallic nanoparticles, both of which possess nonlinear dielectric ...

  15. Enhanced photocatalytic properties in well-ordered mesoporous WO3

    KAUST Repository

    Li, Li

    2010-01-01

    We used polyisoprene-block-ethyleneoxide copolymers as structure-directing agents to synthesise well-ordered and highly-crystalline mesoporous WO 3 architectures that possess improved photocatalytic properties due to enhanced dye-adsorption in absence of diffusion limitation. © 2010 The Royal Society of Chemistry.

  16. A comparative study of the flow enhancing properties of bentonite ...

    African Journals Online (AJOL)

    A comparative study of granule flow enhancing property of bentonite, magnesium stearate, talc and microcrystalline cellulose (MCC) was undertaken. Bentonite was processed into fine powder. A 10 %w/w of starch granules was prepared and separated into different sizes (˂180, 180-500, 500-710 and 710-850 μm).

  17. Pharmacological Inhibition of Gal-3 in Mesenchymal Stem Cells Enhances Their Capacity to Promote Alternative Activation of Macrophages in Dextran Sulphate Sodium-Induced Colitis

    Directory of Open Access Journals (Sweden)

    Bojana Simovic Markovic

    2016-01-01

    Full Text Available Transplantation of mesenchymal stem cells (MSCs reduces the severity of dextran sulphate sodium- (DSS- induced colitis. MSCs are able to secrete Galectin-3 (Gal-3, a protein known to affect proliferation, adhesion, and migration of immune cells. We investigate whether newly synthetized inhibitor of Gal-3 (Davanat will affect production of Gal-3 in MSCs and enhance their potential to attenuate DSS-induced colitis. Pharmacological inhibition of Gal-3 in MSCs enhances their capacity to promote alternative activation of peritoneal macrophages in vitro and in vivo. Injection of MSCs cultured in the presence of Davanat increased concentration of IL-10 in sera of DSS-treated animals and markedly enhanced presence of alternatively activated and IL-10 producing macrophages in the colons of DSS-treated mice. Pharmacological inhibition of Gal-3 in MSCs significantly attenuates concentration of Gal-3 in sera of DSS-treated animals, indicating that MSCs produce Gal-3 in this disease. In conclusion, our findings indicate that Davanat could be used for improvement of MSC-mediated polarization towards immunosuppressive M2 phenotype of macrophages.

  18. Pharmacological Inhibition of Gal-3 in Mesenchymal Stem Cells Enhances Their Capacity to Promote Alternative Activation of Macrophages in Dextran Sulphate Sodium-Induced Colitis

    Science.gov (United States)

    Simovic Markovic, Bojana; Nikolic, Aleksandar; Gazdic, Marina; Nurkovic, Jasmin; Djordjevic, Irena; Arsenijevic, Nebojsa; Stojkovic, Miodrag; Lukic, Miodrag L.; Volarevic, Vladislav

    2016-01-01

    Transplantation of mesenchymal stem cells (MSCs) reduces the severity of dextran sulphate sodium- (DSS-) induced colitis. MSCs are able to secrete Galectin-3 (Gal-3), a protein known to affect proliferation, adhesion, and migration of immune cells. We investigate whether newly synthetized inhibitor of Gal-3 (Davanat) will affect production of Gal-3 in MSCs and enhance their potential to attenuate DSS-induced colitis. Pharmacological inhibition of Gal-3 in MSCs enhances their capacity to promote alternative activation of peritoneal macrophages in vitro and in vivo. Injection of MSCs cultured in the presence of Davanat increased concentration of IL-10 in sera of DSS-treated animals and markedly enhanced presence of alternatively activated and IL-10 producing macrophages in the colons of DSS-treated mice. Pharmacological inhibition of Gal-3 in MSCs significantly attenuates concentration of Gal-3 in sera of DSS-treated animals, indicating that MSCs produce Gal-3 in this disease. In conclusion, our findings indicate that Davanat could be used for improvement of MSC-mediated polarization towards immunosuppressive M2 phenotype of macrophages. PMID:27057168

  19. Anesthetic pharmacology

    National Research Council Canada - National Science Library

    Evers, Alex S; Maze, M; Kharasch, Evan D

    2011-01-01

    ...: Section 1 introduces the principles of drug action, Section 2 presents the molecular, cellular and integrated physiology of the target organ/functional system and Section 3 reviews the pharmacology...

  20. Physical Properties and Effect in a Battery of Safety Pharmacology Models for Three Structurally Distinct Enteric Polymers Employed as Spray-dried Dispersion Carriers

    Directory of Open Access Journals (Sweden)

    Ryan M Fryer

    2016-10-01

    Full Text Available Establishing a wide therapeutic index (TI for pre-clinical safety is important during lead optimization (LO in research, prior to clinical development, although is often limited by a molecules physiochemical characteristics. Recent advances in the application of the innovative vibrating mesh spray-drying technology to prepare amorphous solid dispersions may offer an opportunity to achieve high plasma concentrations of poorly soluble NCEs to enable testing and establishment of a wide TI in safety pharmacology studies. While some of the amorphous solid dispersion carriers are generally recognized as safe for clinical use, whether they are sufficiently benign to enable in vivo pharmacology studies has not been sufficiently demonstrated. Thus, the physical properties, and effect in a battery of in vivo safety pharmacology models, were assessed in three classes of polymers employed as spray-dried dispersion carriers. The polymers (HPMC-AS, Eudragit, PVAP displayed low affinity with acetone/methanol, suitable for solvent-based spray drying. The water sorption of the polymers was moderate, and the degree of hysteresis of HPMC-AS was smaller than Eudragit and PVAP indicating the intermolecular interaction of water-cellulose molecules is weaker than water-acrylate or water-polyvinyl molecules. The polymer particles were well-suspended without aggregation with a mean particle size less than 3 µm in an aqueous vehicle. When tested in conscious Wistar Han rats in safety pharmacology models (n=6-8/dose/polymer investigating effects on CNS, gastrointestinal, and cardiovascular function, no liabilities were identified at any dose tested (30-300 mg/kg PO, suspension. In brief, the polymers had no effect in a modified Irwin test that included observational and evoked endpoints related to stereotypies, excitation, sedation, pain/anesthesia, autonomic balance, reflexes, and others. No effect of the polymers on gastric emptying or intestinal transit was observed

  1. Effects of drug pharmacokinetic/pharmacodynamic properties, characteristics of medication use, and relevant pharmacological interventions on fall risk in elderly patients

    Directory of Open Access Journals (Sweden)

    Chen Y

    2014-06-01

    Full Text Available Ying Chen,1 Ling-Ling Zhu,2 Quan Zhou3 1Liaison Office of Geriatric VIP Patients, 2First Geriatric VIP Ward, Division of Nursing, 3Department of Pharmacy, Second Affiliated Hospital, School of Medicine, Zhejiang University, Hangzhou, People’s Republic of China Background: Falls among the elderly are an issue internationally and a public health problem that brings substantial economic and quality-of-life burdens to individuals and society. Falls prevention is an important measure of nursing quality and patient safety. Numerous studies have evaluated the association of medication use with fall risk in elderly patients. However, an up-to-date review has not been available to summarize the multifaceted pharmaceutical concerns in the prevention of medication-related falls. Materials and methods: Relevant literature was identified by performing searches in PubMed, Web of Science, and the Cochrane Library, covering the period until February 2014. We included studies that described an association between medications and falls, and effects of drug pharmacokinetic/pharmacodynamic properties, characteristics of medication use, and pharmacological interventions on fall risk in elderly patients. The full text of each included article was critically reviewed, and data interpretation was performed. Results: Fall-risk-increasing drugs (FRIDs include central nervous system-acting agents, cough preparations, nonsteroidal anti-inflammatory drugs, anti-Alzheimer’s agents, antiplatelet agents, calcium antagonists, diuretics, α-blockers, digoxin, hypoglycemic drugs, neurotoxic chemotherapeutic agents, nasal preparations, and antiglaucoma ophthalmic preparations. The degree of medication-related fall risk was dependent on one or some of the following factors: drug pharmacokinetic/pharmacodynamic properties (eg, elimination half-life, metabolic pathway, genetic polymorphism, risk rating of medications despite belonging to the same therapeutic class and

  2. Use of Short Animal-Themed Videos to Enhance Veterinary Students' Mood, Attention, and Understanding of Pharmacology Lectures.

    Science.gov (United States)

    Kogan, Lori R; Hellyer, Pete; Clapp, Tod R; Suchman, Erica; McLean, Jennifer; Schoenfeld-Tacher, Regina

    2017-09-29

    Professional DVM training is inherently stressful and challenging for students. This study evaluated a simple intervention-short breaks during a veterinary pharmacology lecture course in the form of funny/cute animal videos (Mood Induction Procedures, or MIP)-to assess for potential impact on students' mood, interest in material, and perceived understanding of material. Ten YouTube video clips showing cats or dogs were selected to influence students' affective states. The videos were shown in a required pharmacology class offered during the fall semester of the second year of the DVM program at a large, land-grant institution in the Western US. The student cohort consisted of 133 students (20 males, 113 females). Twenty days of the course were randomly chosen for the study and ranged from weeks 2 to 13 of the semester. Sessions in which the videos were played were alternated with sessions in which no video was played, for a total of 10 video days and 10 control days. There were significant differences in all three post-class assessment measures between the experimental (video) days and the control days. Results suggest that showing short cute animal videos in the middle of class positively affected students' mood, interest in material, and self-reported understanding of material. While the results of this study are limited to one student cohort at one institution, the ease of implementation of the technique and relatively low stakes support incorporation of the MIP technique across a variety of basic and clinical science courses.

  3. 2014 Enhanced LAW Glass Property-Composition Models, Phase 2

    Energy Technology Data Exchange (ETDEWEB)

    Muller, Isabelle [The Catholic Univ. of America, Washington, DC (United States); Pegg, Ian L. [The Catholic Univ. of America, Washington, DC (United States); Joseph, Innocent [Energy Solutions, Salt Lake City, UT (United States); Gilbo, Konstantin [The Catholic Univ. of America, Washington, DC (United States)

    2015-10-28

    This report describes the results of testing specified by the Enhanced LAW Glass Property-Composition Models, VSL-13T3050-1, Rev. 0 Test Plan. The work was performed in compliance with the quality assurance requirements specified in the Test Plan. Results required by the Test Plan are reported. The te4st results and this report have been reviewed for correctness, technical adequacy, completeness, and accuracy.

  4. ENHANCEMENT OF SOLUBILITY AND DISSOLUTION PROPERTY OF GRISEOFULVIN BY NANOCRYSTALLIZATION

    OpenAIRE

    Phanchaxari M Dandagi; Sumit Kaushik; Shaktish Telsang

    2011-01-01

    The aim of this study was to develop the formulation of griseofulvin by nanocrystallization for the enhancement of solubility and dissolution property of drug. In the present study the area of interest are drugs belonging to class II of BCS classification. Nanocrystal is a new carrier free colloidal drug delivery system with particle size ranging from 100-1000 nm, and is considered as a viable drug delivery strategy to develop the poorly soluble drugs. In the present work an attempt was made ...

  5. A Review of the Receptor-Binding Properties of p-Synephrine as Related to Its Pharmacological Effects

    Directory of Open Access Journals (Sweden)

    Sidney J. Stohs

    2011-01-01

    Full Text Available Bitter orange (Citrus aurantium extract and its primary protoalkaloid p-synephrine are used widely in weight loss/weight management and sports performance products. Because of structural similarities, the pharmacological effects of p-synephrine are widely assumed to be similar to those of ephedrine, m-synephrine (phenylephrine, and endogenous amine neurotransmitters as norepinephrine and epinephrine. However, small structural changes result in the receptor binding characteristics of these amines that are markedly different, providing a plausible explanation for the paucity of adverse effects associated with the wide-spread consumption of p-synephrine in the form of dietary supplements as well as in various Citrus foods and juices. This paper summarizes the adrenoreceptor binding characteristics of p-synephrine relative to m-synephrine, norepinephrine, and other amines as related to the observed pharmacological effects.

  6. A Review of the Receptor-Binding Properties of p-Synephrine as Related to Its Pharmacological Effects

    Science.gov (United States)

    Stohs, Sidney J.; Preuss, Harry G.; Shara, Mohd

    2011-01-01

    Bitter orange (Citrus aurantium) extract and its primary protoalkaloid p-synephrine are used widely in weight loss/weight management and sports performance products. Because of structural similarities, the pharmacological effects of p-synephrine are widely assumed to be similar to those of ephedrine, m-synephrine (phenylephrine), and endogenous amine neurotransmitters as norepinephrine and epinephrine. However, small structural changes result in the receptor binding characteristics of these amines that are markedly different, providing a plausible explanation for the paucity of adverse effects associated with the wide-spread consumption of p-synephrine in the form of dietary supplements as well as in various Citrus foods and juices. This paper summarizes the adrenoreceptor binding characteristics of p-synephrine relative to m-synephrine, norepinephrine, and other amines as related to the observed pharmacological effects. PMID:21904645

  7. Pharmacological activities and medicinal properties of endemic Moroccan medicinal plant Origanum compactum (Benth and their main compounds

    Directory of Open Access Journals (Sweden)

    Abdelhakim Bouyahya

    2017-10-01

    Full Text Available Oregano [Origanum compactum Benth. (O. compactum, Lamiaceae] is an endemic Moroccan medicinal herb. It is used traditionally to fight against several disorders such as diarrhea, urolithiasis, hypertension, diabetes, and inflammation. A large number of components have been identified and isolated from the essential oil of this plant. Carvacrol, thymol, p-cymene and γ-Terpinene are among the more compounds presented in O. compactum essential oil and considered to be the main biologically active components. Numerous experimental studies showed that O. compactum organic extracts, essentials oil and its main compounds possess a broader spectrum of pharmacological and therapeutic activities such as antibacterial, antifungal, antioxidant, and anticancer activity. The present review attempts to give an overview of pharmacological studies of O. compactum and its major compounds.

  8. Synthesis, Characterization, and Enhanced Magnetic Properties of Iron Carbide Nanomaterials

    Science.gov (United States)

    Williams, Brent M.

    Permanent magnets are classified as hard magnetic materials with the main purpose of generating flux for applications such as electric motors, turbines, and hard drives. High coercivity, magnetic remanence, and saturation values with high stability are some of the requirements for permanent magnets. Rare-earth magnets including neodymium and samarium based magnets are known to have superior magnetic properties due to their high magnetocrystalline anisotropy. However, due to the price of rare-earth materials development of alternate permanent magnets composed of inexpensive materials is an ongoing process. Previously cobalt carbide (CoxC) have shown promise as a potential rare-earth free magnet alternative with magnetic properties comparable to that of hexaferrite materials. Unfortunately, CoxC magnets have a low magnetic saturation (50 emu g-1) which drastically lowers its energy product. Alternatively, iron carbide has a rather high bulk magnetization value of 140 emu g-1 and is composed of naturally abundant materials. The sole issue of iron carbide is that it is considered an intermediate magnet with properties between those of a hard and a soft magnetic material. The main focus of this work is the enhancement of the hard magnetic properties of iron carbide through size effect, shape anisotropy, magnetocrystalline anisotropy and exchange anisotropy. First a wet synthesis method was developed which utilized hexadecyltrimethylammonium chloride to control particle size, shape, and crystal structure to manipulate the magnetic properties of iron carbide. With this method a semi-hard 50 nm orthorhombic Fe3C phase and a magnetically soft single crystal hexagonal Fe7C3 structure with texture-induced magnetic properties were developed. The properties for both materials were further enhanced through formation of exchange bias Fe3C/CoO nanoaggregates and spring exchange coupling of the ferromagnetically hard and soft phases of Fe7C3/SrFe 12O19. A 33% increase in coercivity

  9. Clinical pharmacology

    African Journals Online (AJOL)

    Clinical pharmacology. Acute pain management in children. Early and appropriate pain management, and the reduction of pain during diagnostic and therapeutic procedures, are essential in all trauma patients, but paediatric patients present particular challenges. Appropriate analgesia, as well as appropriate routes.

  10. Enhanced thermoelectric properties in boron nitride quantum-dot

    Directory of Open Access Journals (Sweden)

    Changning Pan

    Full Text Available We have investigated the ballistic thermoelectric properties in boron nitride quantum dots by using the nonequilibrium Green’s function approach and the Landauer transport theory. The result shows that the phonon transport is substantially suppressed by the interface in the quantum dots. The resonant tunneling effect of electron leads to the fluctuations of the electronic conductance. It enhances significantly the Seebeck coefficient. Combined with the low thermal conductance of phonon, the high thermoelectric figure of merit ZT ∼0.78 can be obtained at room temperature T = 300 K and ZT ∼0.95 at low temperature T = 100 K. It is much higher than that of graphene quantum dots with the same geometry parameters, which is ZT ∼0.29 at room temperature T = 300 K and ZT ∼0.48 at low temperature T = 100 K. The underlying mechanism is that the boron nitride quantum dots possess higher thermopower and lower phonon thermal conductance than the graphene quantum dots. Thus the results indicate that the thermoelectric properties of boron nitride can be significantly enhanced by the quantum dot and are better than those of graphene. Keywords: Thermoelectric properties, Boron nitride quantum dot, Electron transport, Phonon transport

  11. Enhancement of mechanical properties of epoxy/graphene nanocomposite

    Science.gov (United States)

    Berhanuddin, N. I. C.; Zaman, I.; Rozlan, S. A. M.; Karim, M. A. A.; Manshoor, B.; Khalid, A.; Chan, S. W.; Meng, Q.

    2017-10-01

    Graphene is a novel class of nanofillers possessing outstanding characteristics including most compatible with most polymers, high absolute strength, high aspect ratio and cost effectiveness. In this study, graphene was used to reinforce epoxy as a matrix, to enhance its mechanical properties. Two types of epoxy composite were developed which are epoxy/graphene nanocomposite and epoxy/modified graphene nanocomposite. The fabrication of graphene was going through thermal expansion and sonication process. Chemical modification was only done for modified graphene where 4,4’-Methylene diphenyl diisocyanate (MDI) is used. The mechanical properties of both nanocomposite, such as Young’s modulus and maximum stress were investigated. Three weight percentage were used for this study which are 0.5 wt%, 1.0 wt% and 1.5 wt%. At 0.5 wt%, modified and unmodified shows the highest value compared to neat epoxy, where the value were 8 GPa, 6 GPa and 0.675 GPa, respectively. For maximum stress, neat epoxy showed the best result compared to both nanocomposite due to the changes of material properties when adding the filler into the matrix. Therefore, both nanocomposite increase the mechanical properties of the epoxy, however modification surface of graphene gives better improvement.

  12. Glass Fiber Reinforced Polypropylene Mechanical Properties Enhancement by Adhesion Improvement

    Directory of Open Access Journals (Sweden)

    Mariana Etcheverry

    2012-06-01

    Full Text Available Glass fibers (GF are the reinforcement agent most used in polypropylene (PP based composites, as they have good balance between properties and costs. However, their final properties are mainly determined by the strength and stability of the polymer-fiber interphase. Fibers do not act as an effective reinforcing material when the adhesion is weak. Also, the adhesion between phases can be easily degraded in aggressive environmental conditions such as high temperatures and/or elevated moisture, and by the stress fields to which the material may be exposed. Many efforts have been done to improve polymer-glass fiber adhesion by compatibility enhancement. The most used techniques include modifications in glass surface, polymer matrix and/or both. However, the results obtained do not show a good costs/properties improvement relationship. The aim of this work is to perform an accurate analysis regarding methods for GF/PP adhesion improvement and to propose a new route based on PP in-situ polymerization onto fibers. This route involves the modification of fibers with an aluminum alkyl and hydroxy-α-olefin and from there to enable the growth of the PP chains using direct metallocenic copolymerization. The adhesion improvements were further proved by fragmentation test, as well as by mechanical properties measurements. The strength and toughness increases three times and the interfacial strength duplicates in PP/GF composites prepared with in-situ polymerized fibers.

  13. Pharmacological treatment with inhibitors of nuclear export enhances the antitumor activity of docetaxel in human prostate cancer.

    Science.gov (United States)

    Gravina, Giovanni Luca; Mancini, Andrea; Colapietro, Alessandro; Marampon, Francesco; Sferra, Roberta; Pompili, Simona; Biordi, Leda Assunta; Iorio, Roberto; Flati, Vincenzo; Argueta, Christian; Landesman, Yosef; Kauffman, Michael; Shacham, Sharon; Festuccia, Claudio

    2017-12-19

    Docetaxel (DTX) modestly increases patient survival of metastatic castration-resistant prostate cancer (mCRPC) due to insurgence of pharmacological resistance. Deregulation of Chromosome Region Maintenance (CRM-1)/ exportin-1 (XPO-1)-mediated nuclear export may play a crucial role in this phenomenon. Here, we evaluated the effects of two Selective Inhibitor of Nuclear Export (SINE) compounds, selinexor (KPT-330) and KPT-251, in association with DTX by using 22rv1, PC3 and DU145 cell lines with their. DTX resistant derivatives. We show that DTX resistance may involve overexpression of β-III tubulin (TUBB3) and P-glycoprotein as well as increased cytoplasmic accumulation of Foxo3a. Increased levels of XPO-1 were also observed in DTX resistant cells suggesting that SINE compounds may modulate DTX effectiveness in sensitive cells as well as restore the sensitivity to DTX in resistant ones. Pretreatment with SINE compounds, indeed, sensitized to DTX through increased tumor shrinkage and apoptosis by preventing DTX-induced cell cycle arrest. Basally SINE compounds induce FOXO3a activation and nuclear accumulation increasing the expression of FOXO-responsive genes including p21, p27 and Bim causing cell cycle arrest. SINE compounds-catenin and survivin supporting apoptosis. βdown-regulated Cyclin D1, c-myc, Nuclear sequestration of p-Foxo3a was able to reduce ABCB1 and TUBB3 H2AX levels, prolonged γ expression. Selinexor treatment increased DTX-mediated double strand breaks (DSB), and reduced the levels of DNA repairing proteins including DNA PKc and Topo2A. Our results provide supportive evidence for the therapeutic use of SINE compounds in combination with DTX suggesting their clinical use in mCRPC patients.

  14. Superoxide Dismutase Mimetic GC4419 Enhances the Oxidation of Pharmacological Ascorbate and Its Anticancer Effects in an H2O2-Dependent Manner

    Directory of Open Access Journals (Sweden)

    Collin D. Heer

    2018-01-01

    Full Text Available Lung cancer, together with head and neck cancer, accounts for more than one-fourth of cancer deaths worldwide. New, non-toxic therapeutic approaches are needed. High-dose IV vitamin C (aka, pharmacological ascorbate; P-AscH− represents a promising adjuvant to radiochemotherapy that exerts its anti-cancer effects via metal-catalyzed oxidation to form H2O2. Mn(III-porphyrins possessing superoxide dismutase (SOD mimetic activity have been shown to increase the rate of oxidation of AscH−, enhancing the anti-tumor effects of AscH− in several cancer types. The current study demonstrates that the Mn(II-containing pentaazamacrocyclic selective SOD mimetic GC4419 may serve as an AscH−/O2•− oxidoreductase as evidenced by the increased rate of oxygen consumption, steady-state concentrations of ascorbate radical, and H2O2 production in complete cell culture media. GC4419, but not CuZnSOD, was shown to significantly enhance the toxicity of AscH− in H1299, SCC25, SQ20B, and Cal27 cancer cell lines. This enhanced cancer cell killing was dependent upon the catalytic activity of the SOD mimetic and the generation of H2O2, as determined using conditional overexpression of catalase in H1299T cells. GC4419 combined with AscH− was also capable of enhancing radiation-induced cancer cell killing. Currently, AscH− and GC4419 are each being tested separately in clinical trials in combination with radiation therapy. Data presented here support the hypothesis that the combination of GC4419 and AscH− may provide an effective means by which to further enhance radiation therapy responses.

  15. Pharmacological properties of blister beetles (Coleoptera: Meloidae) promoted their integration into the cultural heritage of native rural Spain as inferred by vernacular names diversity, traditions, and mitochondrial DNA.

    Science.gov (United States)

    Percino-Daniel, Nohemí; Buckley, David; García-París, Mario

    2013-06-03

    Beetles of the family Meloidae (blister beetles) are often reported in pharmacological literature because of their content of cantharidin. Cantharidin has a long history in human medicine and was commonly applied in the 19th and the early 20th centuries, although its use has been progressively abandoned since then. Contrary to most, even common, large species of Coleoptera, blister beetles of the genera Berberomeloe, Physomeloe and to a lesser extent Meloe, are usually recognized and often incorporated into local folk taxonomy by inhabitants of rural areas in Spain. To demonstrate the role that pharmacological properties of blister beetles must have played in their integration in the culture of early Iberian human societies, but also in the preservation of their identity until today, a rare case for Spanish insects. To achieve this purpose we document the diversity of vernacular names applied in rural areas of Spain, and we determine, using molecular data, the antiquity of the presence of two species of the better-known blister beetle in rural Spain, Berberomeloe majalis and Berberomeloe insignis. We try to document the extent of traditional knowledge of meloid beetles in rural areas by interviewing about 120 people from villages in central and southern Spain. We also use mitochondrial DNA sequences (Cytochrome Oxidase I and 16SrRNA) obtained from several populations of two species of the better known blister beetle in rural Spain, Berberomeloe majalis and Berberomeloe insignis, to determine whether these beetles were already present in the Iberian Peninsula when earlier ancient cultures were developing. Our results show that, based on mitochondrial DNA, blister beetles of the genus Berberomeloe were present in the Iberian Peninsula long before humans arrived, so ancient Iberian cultures were in contact with the same beetle species occurring now in rural areas. On the other hand, people interviewed in rural communities provided us with more than 28 different

  16. Phytochemical properties and pharmacological effects of Quercus ilex L. aqueous extract on gastrointestinal physiological parameters in vitro and in vivo.

    Science.gov (United States)

    Rtibi, Kaïs; Hammami, Imen; Selmi, Slimen; Grami, Dhekra; Sebai, Hichem; Amri, Mohamed; Marzouki, Lamjed

    2017-10-01

    Several research studies have reported on the pharmacological relevance of the medicinal plants used for treating various gastrointestinal disorders and controlling the dietary glucose uptake in the intestinal tract. Male rats were used to investigate the pharmacological effects of green oak acorn aqueous extract (GOAE) on gastrointestinal physiological parameters in vivo and in vitro. In this respect, the gastro-intestinal motility and hypersecretion essays were evaluated using a simple test meal (10% charcoal in 5% gum arabic) and castor oil induced diarrhea. However, the effect of GOAE on glucose absorption and homeostasis was assessed by the Ussing chamber system and oral glucose tolerance test (OGTT) measures. Various doses of the Quercus ilex aqueous extract (125, 250 and 500mgkg -1 ) administered orally produced a significantly dose-related inhibition of gut meal travel distance in normal rat. The highest intestinal transit reduction of 49.34% was obtained with 500mgkg -1 compared to 58.33% caused by reference drug (clonidine, 1mgkg -1 ). In castor oil induced diarrhea in rat, Q. ilex extract reduced the frequency of defecation, fluid accumulation and electrolyte transport. These effects were associated with decreased histopathological damage and regulation of intracellular mediators disturbance in the intestinal mucosa. In addition, GOAE treatment improved glucose tolerance and significantly and dose-dependently reduced (>50%) the glucose absorption via intestinal epithelium. Phytochemical screening revealed the presence of many bioactive natural compounds. These results suggest that the extract was effective towards reducing diarrhea, fluid accumulation, electrolyte transport and glucose absorption, and no toxic effects of the GOAE presented on this study. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  17. Phytochemistry, pharmacology, and clinical trials of Morus alba.

    Science.gov (United States)

    Chan, Eric Wei-Chiang; Lye, Phui-Yan; Wong, Siu-Kuin

    2016-01-01

    The present review is aimed at providing a comprehensive summary on the botany, utility, phytochemistry, pharmacology, and clinical trials of Morus alba (mulberry or sang shu). The mulberry foliage has remained the primary food for silkworms for centuries. Its leaves have also been used as animal feed for livestock and its fruits have been made into a variety of food products. With flavonoids as major constituents, mulberry leaves possess various biological activities, including antioxidant, antimicrobial, skin-whitening, cytotoxic, anti-diabetic, glucosidase inhibition, anti-hyperlipidemic, anti-atherosclerotic, anti-obesity, cardioprotective, and cognitive enhancement activities. Rich in anthocyanins and alkaloids, mulberry fruits have pharmacological properties, such as antioxidant, anti-diabetic, anti-atherosclerotic, anti-obesity, and hepatoprotective activities. The root bark of mulberry, containing flavonoids, alkaloids and stilbenoids, has antimicrobial, skin-whitening, cytotoxic, anti-inflammatory, and anti-hyperlipidemic properties. Other pharmacological properties of M. alba include anti-platelet, anxiolytic, anti-asthmatic, anthelmintic, antidepressant, cardioprotective, and immunomodulatory activities. Clinical trials on the efficiency of M. alba extracts in reducing blood glucose and cholesterol levels and enhancing cognitive ability have been conducted. The phytochemistry and pharmacology of the different parts of the mulberry tree confer its traditional and current uses as fodder, food, cosmetics, and medicine. Overall, M. alba is a multi-functional plant with promising medicinal properties. Copyright © 2016 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

  18. Magnetic nanofluid properties as the heat transfer enhancement agent

    Directory of Open Access Journals (Sweden)

    Roszko Aleksandra

    2016-01-01

    Full Text Available The main purpose of this paper was to investigate an influence of various parameters on the heat transfer processes with strong magnetic field utilization. Two positions of experimental enclosure in magnetic environment, two methods of preparation and three different concentrations of nanoparticles (0.0112, 0.056 and 0.112 vol.% were taken into account together with the magnetic field strength. Analysed nanofluids consisted of distilled water (diamagnetic and Cu/CuO particles (paramagnetic of 40–60 nm size. The nanofluids components had different magnetic properties what caused complex interaction of forces’ system. The heat transfer data and fluid flow structure demonstrated the influence of magnetic field on the convective phenomena. The most visible consequence of magnetic field application was the heat transfer enhancement and flow reorganization under applied conditions.

  19. Behavioural pharmacology of the α5-GABAA receptor antagonist S44819: Enhancement and remediation of cognitive performance in preclinical models.

    Science.gov (United States)

    Gacsályi, István; Móricz, Krisztina; Gigler, Gábor; Wellmann, János; Nagy, Katalin; Ling, István; Barkóczy, József; Haller, József; Lambert, Jeremy J; Szénási, Gábor; Spedding, Michael; Antoni, Ferenc A

    2017-10-01

    Previous work has shown that S44819 is a novel GABAA receptor (GABAAR) antagonist, which is selective for extrasynaptic GABAARs incorporating the α5 subunit (α5-GABAARs). The present study reports on the preclinical neuropsychopharmacological profile of S44819. Significantly, no sedative or pro-convulsive side effects of S44819 were found at doses up to 30 mg/kg i.p. Object recognition (OR) memory in intact mice was enhanced by S44819 (0.3 mg/kg p.o.) given before the acquisition trial. Mice treated with phencyclidine for two weeks and tested six days after the cessation of treatment failed to show OR memory. This deficit was corrected by a single administration of S44819 (0.1, 0.3 or 1 mg/kg p.o.) prior to the acquisition trial. The amnestic effect of ketamine in rats tested in the eight-arm radial maze (reference and working memory versions) was blocked by S44819 (3 mg/kg p.o.). Extinction of cued fear was preserved during treatment with S44819 (3 mg/kg/diem i.p.). Administration of S44819 had no significant effect in the Vogel-conflict test, the elevated plus maze, the forced swim, the marble-burying and the tail-suspension tests. In contrast, anxiolytic/antidepressant-like effects of the compound were found in paradigms that have mnemonic components, such as social interaction, fear-potentiated startle and social avoidance induced by negative life experience. In summary, S44819 enhanced intact recognition memory and ameliorated memory deficits induced by inhibition of NMDA receptors. Anxiolytic/antidepressant efficacy was limited to paradigms involving cognitive function. In conclusion, S44819 is a novel psychoactive pro-cognitive compound with potential as a therapeutic agent in dementia. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Pharmacological and physiological properties of a putative ganglionic nicotinic receptor, alpha 3 beta 4, expressed in transfected eucaryotic cells.

    Science.gov (United States)

    Wong, E T; Holstad, S G; Mennerick, S J; Hong, S E; Zorumski, C F; Isenberg, K E

    1995-01-01

    Neuronal nicotinic acetylcholine receptor subunits alpha 3 (PCA48E) and beta 4S (ZPC13) were expressed in human embryonic kidney (HEK)-293 cells by calcium phosphate transfection. In the presence of atropine, acetylcholine (ACh) induced fast activating currents which exhibited desensitization and inward rectification. The EC50 for ACh was 202 +/- 32 microM with a Hill coefficient of 1.9 +/- 0.4. The rank order of nicotinic agonist potency was 1,1-dimethyl-4-phenylpiperozinium (DMPP) > cytisine = nicotine approximately equal to ACh. The maximal response elicited by DMPP was substantially less than that elicited by other agonists, suggesting that DMPP is a partial agonist. ACh (500 microM) responses were very effectively blocked by equimolar concentrations (100 microM) of the ganglionic antagonists d-tubocurarine, mecamylamine and hexamethonium. Equal concentrations of the potent muscle receptor antagonist decamethonium and the competitive antagonist dihydro-beta-erythroidine were much less effective. alpha bungaro-toxin (1 microM) had little effect on ACh-induced responses. This physiological and pharmacological profile is consistent with a ganglionic nicotinic response.

  1. Enhanced tensile properties of magnesium composites reinforced with graphene nanoplatelets

    Energy Technology Data Exchange (ETDEWEB)

    Rashad, Muhammad, E-mail: rashadphy87@gmail.com [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China); Pan, Fusheng, E-mail: fspan@cqu.edu.cn [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China); Chongqing Academy of Science and Technology, Chongqing 401123 (China); Hu, Huanhuan [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China); Asif, Muhammad [School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024 (China); Hussain, Shahid [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); She, Jia [College of Materials Science and Engineering, Chongqing University, Chongqing 400044 (China); National Engineering Research Center for Magnesium Alloys, Chongqing University, Chongqing 400044 (China)

    2015-04-10

    The aim of this study is to fabricate magnesium reinforced metal matrix composites using graphene nanoplatelets (GNPs) via powder metallurgy processing in order to enhance room temperature mechanical properties. The microstructural evaluation and mechanical behaviors of composite powders and extruded bulk materials were examined by X-ray diffraction (XRD), differential scanning calorimetry (DSC), Raman spectroscopy, transmission electron microscopy (TEM), scanning electron microscopy (SEM) equipped with energy-dispersive spectrometer and mechanical tests. The uniform dispersion and large specific surface area per volume of GNPs embedded in magnesium matrix led to increament in microhardness, tensile strength and fracture strains of the composites. For example, when employing the pure magnesium reinforced with 0.30 wt% GNPs, the increase of Young's modulus, yield strength, and failure strain of extruded nanocomposite was +131%, +49.5% and +74.2% respectively, compared to those of extruded materials with no GNPs additive. Additionally, mechanical properties of synthesized composites were compared with previously reported Mg–CNTs composites. It was found that GNPs outperform CNTs due their high specific surface area.

  2. Novel oral anticoagulants in non-valvular atrial fibrillation: Pharmacological properties, clinical trials, guideline recommendations, new antidote drugs and real-world data

    Directory of Open Access Journals (Sweden)

    Umut Kocabas

    2016-12-01

    Full Text Available Atrial fibrillation (AF is the most common sustained cardiac arrhythmia. Ischemic stroke and systemic thromboembolism are the most fatal complications of AF. Vitamin K antagonists (VKA are used in the prevention of AF-related stroke and systemic thromboembolism. However, the use of VKAs is associated with limitations such as their narrow therapeutic index, the need for monitoring, and numerous food-drug interactions. Novel oral anticoagulants (NOACs developed by researchers do not have those limitations and are better tolerated in patients with non-valvular atrial fibrillation. In this review, the pharmacological properties of NOACs, the results of NOAC clinical trials, the guideline recommendations, the important aspects of patient selection and clinical practice, new antidote drugs for NOACs and real-world data of NOACs in patients with non-valvular atrial fibrillation have been discussed.

  3. Design of materials configurations for enhanced phononic and electronic properties

    Science.gov (United States)

    Daraio, Chiara

    The discovery of novel nonlinear dynamic and electronic phenomena is presented for the specific cases of granular materials and carbon nanotubes. This research was conducted for designing and constructing optimized macro-, micro- and nano-scale structural configurations of materials, and for studying their phononic and electronic behavior. Variation of composite arrangements of granular elements with different elastic properties in a linear chain-of-sphere, Y-junction or 3-D configurations led to a variety of novel phononic phenomena and interesting physical properties, which can be potentially useful for security, communications, mechanical and biomedical engineering applications. Mechanical and electronic properties of carbon nanotubes with different atomic arrangements and microstructures were also investigated. Electronic properties of Y-junction configured carbon nanotubes exhibit an exciting transistor switch behavior which is not seen in linear configuration nanotubes. Strongly nonlinear materials were designed and fabricated using novel and innovative concepts. Due to their unique strongly nonlinear and anisotropic nature, novel wave phenomena have been discovered. Specifically, violations of Snell's law were detected and a new mechanism of wave interaction with interfaces between NTPCs (Nonlinear Tunable Phononic Crystals) was established. Polymer-based systems were tested for the first time, and the tunability of the solitary waves speed was demonstrated. New materials with transformed signal propagation speed in the manageable range of 10-100 m/s and signal amplitude typical for audible speech have been developed. The enhancing of the mitigation of solitary and shock waves in 1-D chains were demonstrated and a new protective medium was designed for practical applications. 1-D, 2-D and 3-D strongly nonlinear system have been investigated providing a broad impact on the whole area of strongly nonlinear wave dynamics and creating experimental basis for new

  4. Pharmacological Effects of Rosa Damascena

    OpenAIRE

    Boskabady, Mohammad Hossein; Shafei, Mohammad Naser; Saberi, Zahra; Amini, Somayeh

    2011-01-01

    Rosa damascena mill L., known as Gole Mohammadi in is one of the most important species of Rosaceae family flowers. R. damascena is an ornamental plant and beside perfuming effect, several pharmacological properties including anti-HIV, antibacterial, antioxidant, antitussive, hypnotic, antidiabetic, and relaxant effect on tracheal chains have been reported for this plant. This article is a comprehensive review on pharmacological effects of R. damascena. Online literature searches were perform...

  5. Nanoscale structural modulation and enhanced room-temperature multiferroic properties

    Science.gov (United States)

    Sun, Shujie; Huang, Yan; Wang, Guopeng; Wang, Jianlin; Fu, Zhengping; Peng, Ranran; Knize, Randy J.; Lu, Yalin

    2014-10-01

    Availability of a single-phase multiferroic material functional at room temperature poses a big challenge, although it is very important to both fundamental physics and application development. Recently, layered Aurivillius oxide materials, one of the most promising candidates, have attracted considerable interest. In this work, we investigated the nanoscale structural evolution of the six-layer Bi7Fe3-xCoxTi3O21 when substituting excessive Co. Nanoscale structural modulation (NSM) occurred at the boundaries when changing the material gradually from the originally designed six-layer nanoscale architecture down to five and then four, when increasing the Co content, inducing a previously unidentified analogous morphotropic transformation (AMT) effect. The AMT's net contribution to the enhanced intrinsic multiferroic properties at room temperature was confirmed by quantifying and deducting the contribution from the existing impurity phase using derivative thermo-magneto-gravimetry measurements (DTMG). Significantly, this new AMT effect may be caused by a possible coupling contribution from co-existing NSM phases, indicating a potential method for realizing multiferroic materials that function at room temperature.Availability of a single-phase multiferroic material functional at room temperature poses a big challenge, although it is very important to both fundamental physics and application development. Recently, layered Aurivillius oxide materials, one of the most promising candidates, have attracted considerable interest. In this work, we investigated the nanoscale structural evolution of the six-layer Bi7Fe3-xCoxTi3O21 when substituting excessive Co. Nanoscale structural modulation (NSM) occurred at the boundaries when changing the material gradually from the originally designed six-layer nanoscale architecture down to five and then four, when increasing the Co content, inducing a previously unidentified analogous morphotropic transformation (AMT) effect. The AMT

  6. Gallium enhances reconstructive properties of a calcium phosphate bone biomaterial.

    Science.gov (United States)

    Strazic Geljic, Ivana; Melis, Nicolas; Boukhechba, Florian; Schaub, Sébastien; Mellier, Charlotte; Janvier, Pascal; Laugier, Jean-Pierre; Bouler, Jean-Michel; Verron, Elise; Scimeca, Jean-Claude

    2018-02-01

    Calcium phosphate (CaP)-based biomaterials are commonly used in bone reconstructive surgery to replace the damaged tissue, and can also serve as vectors for local drug delivery. Due to its inhibitory action on osteoclasts, the semi-metallic element gallium (Ga) is used for the systemic treatment of disorders associated with accelerated bone resorption. As it was demonstrated that Ga could be incorporated in the structure of CaP biomaterials, we investigated the biological properties of Ga-loaded CaP biomaterials. Culturing bone cells on Ga-CaP, we observed a decrease in osteoclast number and a downregulation of late osteoclastic markers expression, while Ga-CaP upregulated the expression of osteoblastic marker genes involved in the maturation of bone matrix. We next investigated in vivo bone reconstructive properties of different Ga-loaded biomaterials using a murine bone defect healing model. All implanted biomaterials showed a good osseointegration into the surrounding host tissue, accompanied by a successful bone ingrowth and bone marrow reconstruction, as evidenced by histological analysis. Moreover, quantitative micro-computed tomography analysis of implants revealed that Ga enhanced total defect filling. Lastly, we took advantage for the first time of a particular mode of non-linear microscopy (second harmonic generation) to quantify in vivo bone tissue reconstruction within a CaP bone substitute. By doing so, we showed that Ga exerted a positive impact on mature organized collagen synthesis. As a whole, our data support the hypothesis that Ga represents an attractive additive to CaP biomaterials for bone reconstructive surgery. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  7. Pharmacological study of the antitussive and respiratory-analeptic properties of N-(2'-ethylpyrrolidino)diphenylacetamide hydrochloride (F 1459).

    Science.gov (United States)

    Tarayre, J P; Vilain, P; Lauressergues, H; Cauquil, J; Bru, M; Caillol, V; Pouget, G; Jougla, A M; Go, M

    1983-01-01

    The antitussive and respiratory stimulant properties of N-(2'-ethylpyrrolidino)diphenylacetamide hydrochloride (F 1459) in animals are reported. In the mechanical stimulation of the trachea in guinea pigs and after intraperitoneal administration of the product, F 1459 showed a better antitussive action as compared to oxeladin, zipeprol, codeine and clobutinol. Low intraduodenal doses of F 1459 also reduced in cats the cough induced by the electrical stimulation of the superior laryngeal nerve. In anesthetized dogs whose respiratory functions had been depressed by morphine, F 1459 significantly increased the volume inspired per minute, an effect not due to any uncoupling effect on oxidative phosphorylation. F 1459 has local anesthetic and broncholytic properties that may play a role in the mechanism of its antitussive action. Contrarily to codeine, the test compound did not induce a decrease in the intestinal transit.

  8. Pharmacological Properties of Biocompounds from Spores of the Lingzhi or Reishi Medicinal Mushroom Ganoderma lucidum (Agaricomycetes): A Review.

    Science.gov (United States)

    Soccol, Carlos Ricardo; Bissoqui, Lucas Yamasaki; Rodrigues, Cristine; Rubel, Rosalia; Sella, Sandra R B R; Leifa, Fan; de Souza Vandenberghe, Luciana Porto; Soccol, Vanete Thomaz

    2016-01-01

    Ganoderma lucidum is a well-known representative of mushrooms that have been used in traditional Chinese medicine for centuries. New discoveries related to this medicinal mushroom and its biological properties are frequently reported. However, only recently have scientists started to pay special attention to G. lucidum spores. This is in part because of the recent development of methods for breaking the spore wall and extracting biocompounds from the spore. Although some research groups are working with G. lucidum spores, data in the literature are still limited, and the methods used have not been systematized. This review therefore describes the main advances in techniques for breaking the spore wall and extracting biocompounds from the spore. In addition, the major active components identified and their biological properties, such as neurological activity and antiaging and cell-protective effects, are investigated because these are of importance for potential drug development.

  9. In Vitro Characterization of the Pharmacological Properties of the Anti-Cancer Chelator, Bp4eT, and Its Phase I Metabolites.

    Directory of Open Access Journals (Sweden)

    Eliška Potůčková

    Full Text Available Cancer cells have a high iron requirement and many experimental studies, as well as clinical trials, have demonstrated that iron chelators are potential anti-cancer agents. The ligand, 2-benzoylpyridine 4-ethyl-3-thiosemicarbazone (Bp4eT, demonstrates both potent anti-neoplastic and anti-retroviral properties. In this study, Bp4eT and its recently identified amidrazone and semicarbazone metabolites were examined and compared with respect to their anti-proliferative activity towards cancer cells (HL-60 human promyelocytic leukemia, MCF-7 human breast adenocarcinoma, HCT116 human colon carcinoma and A549 human lung adenocarcinoma, non-cancerous cells (H9c2 neonatal rat-derived cardiomyoblasts and 3T3 mouse embryo fibroblasts and their interaction with intracellular iron pools. Bp4eT was demonstrated to be a highly potent and selective anti-neoplastic agent that induces S phase cell cycle arrest, mitochondrial depolarization and apoptosis in MCF-7 cells. Both semicarbazone and amidrazone metabolites showed at least a 300-fold decrease in cytotoxic activity than Bp4eT towards both cancer and normal cell lines. The metabolites also lost the ability to: (1 promote the redox cycling of iron; (2 bind and mobilize iron from labile intracellular pools; and (3 prevent 59Fe uptake from 59Fe-labeled transferrin by MCF-7 cells. Hence, this study demonstrates that the highly active ligand, Bp4eT, is metabolized to non-toxic and pharmacologically inactive analogs, which most likely contribute to its favorable pharmacological profile. These findings are important for the further development of this drug candidate and contribute to the understanding of the structure-activity relationships of these agents.

  10. Elastic Properties and Enhanced Piezoelectric Response at Morphotropic Phase Boundaries

    Science.gov (United States)

    Cordero, Francesco

    2015-01-01

    The search for improved piezoelectric materials is based on the morphotropic phase boundaries (MPB) between ferroelectric phases with different crystal symmetry and available directions for the spontaneous polarization. Such regions of the composition x−T phase diagrams provide the conditions for minimal anisotropy with respect to the direction of the polarization, so that the polarization can easily rotate maintaining a substantial magnitude, while the near verticality of the TMPBx boundary extends the temperature range of the resulting enhanced piezoelectricity. Another consequence of the quasi-isotropy of the free energy is a reduction of the domain walls energies, with consequent formation of domain structures down to nanoscale. Disentangling the extrinsic and intrinsic contributions to the piezoelectricity in such conditions requires a high level of sophistication from the techniques and analyses for studying the structural, ferroelectric and dielectric properties. The elastic characterization is extremely useful in clarifying the phenomenology and mechanisms related to ferroelectric MPBs. The relationship between dielectric, elastic and piezoelectric responses is introduced in terms of relaxation of defects with electric dipole and elastic quadrupole, and extended to the response near phase transitions in the framework of the Landau theory. An account is provided of the anelastic experiments, from torsional pendulum to Brillouin scattering, that provided new important information on ferroelectric MPBs, including PZT, PMN-PT, NBT-BT, BCTZ, and KNN-based systems. PMID:28793707

  11. Elastic Properties and Enhanced Piezoelectric Response at Morphotropic Phase Boundaries

    Directory of Open Access Journals (Sweden)

    Francesco Cordero

    2015-12-01

    Full Text Available The search for improved piezoelectric materials is based on the morphotropic phase boundaries (MPB between ferroelectric phases with different crystal symmetry and available directions for the spontaneous polarization. Such regions of the composition x − T phase diagrams provide the conditions for minimal anisotropy with respect to the direction of the polarization, so that the polarization can easily rotate maintaining a substantial magnitude, while the near verticality of the TMPB(x boundary extends the temperature range of the resulting enhanced piezoelectricity. Another consequence of the quasi-isotropy of the free energy is a reduction of the domain walls energies, with consequent formation of domain structures down to nanoscale. Disentangling the extrinsic and intrinsic contributions to the piezoelectricity in such conditions requires a high level of sophistication from the techniques and analyses for studying the structural, ferroelectric and dielectric properties. The elastic characterization is extremely useful in clarifying the phenomenology and mechanisms related to ferroelectric MPBs. The relationship between dielectric, elastic and piezoelectric responses is introduced in terms of relaxation of defects with electric dipole and elastic quadrupole, and extended to the response near phase transitions in the framework of the Landau theory. An account is provided of the anelastic experiments, from torsional pendulum to Brillouin scattering, that provided new important information on ferroelectric MPBs, including PZT, PMN-PT, NBT-BT, BCTZ, and KNN-based systems.

  12. Functional Overload Enhances Satellite Cell Properties in Skeletal Muscle

    Directory of Open Access Journals (Sweden)

    Shin Fujimaki

    2016-01-01

    Full Text Available Skeletal muscle represents a plentiful and accessible source of adult stem cells. Skeletal-muscle-derived stem cells, termed satellite cells, play essential roles in postnatal growth, maintenance, repair, and regeneration of skeletal muscle. Although it is well known that the number of satellite cells increases following physical exercise, functional alterations in satellite cells such as proliferative capacity and differentiation efficiency following exercise and their molecular mechanisms remain unclear. Here, we found that functional overload, which is widely used to model resistance exercise, causes skeletal muscle hypertrophy and converts satellite cells from quiescent state to activated state. Our analysis showed that functional overload induces the expression of MyoD in satellite cells and enhances the proliferative capacity and differentiation potential of these cells. The changes in satellite cell properties coincided with the inactivation of Notch signaling and the activation of Wnt signaling and likely involve modulation by transcription factors of the Sox family. These results indicate the effects of resistance exercise on the regulation of satellite cells and provide insight into the molecular mechanism of satellite cell activation following physical exercise.

  13. New pharmacological properties of Medicago sativa and Saponaria officinalis saponin-rich fractions addressed to Candida albicans.

    Science.gov (United States)

    Sadowska, Beata; Budzyńska, Aleksandra; Więckowska-Szakiel, Marzena; Paszkiewicz, Małgorzata; Stochmal, Anna; Moniuszko-Szajwaj, Barbara; Kowalczyk, Mariusz; Różalska, Barbara

    2014-08-01

    The antifungal activity of the saponin-rich fractions (SFs) from Medicago sativa (aerial parts and roots) and Saponaria officinalis (used as a well-known source of plant saponins) against Candida albicans reference and clinical strains, their yeast-to-hyphal conversion, adhesion, and biofilm formation was investigated. Direct fungicidal/fungistatic properties of the tested phytochemicals used alone, as well as their synergy with azoles (probably resulting from yeast cell wall instability) were demonstrated. Here, to the best of our knowledge, we report for the first time the ability of saponin-rich extracts of M. sativa and S. officinalis to inhibit C. albicans germ tube formation, limit hyphal growth, reduce yeast adherence and biofilm formation, and eradicate mature (24 h) Candida biofilm. Moreover, M. sativa SFs (mainly obtained from aerial parts), in the range of concentrations which were active modulators of Candida virulence factors, exhibited low cytotoxicity against the mouse fibroblast line L929. These properties seem to be very promising in the context of using plant-derived SFs as potential novel antifungal therapeutics supporting classic drugs or as ingredients of disinfectants. © 2014 The Authors.

  14. Pharmacological and pharmaceutical properties of freeze-dried formulations of egg albumin, indomethacin, olive oil, or fatty acids.

    Science.gov (United States)

    Tsuji, Y; Kakegawa, H; Miyataka, H; Matsumoto, H; Satoh, T

    1993-07-01

    Formulations consisting of egg albumin, indomethacin (IND), and olive oil or fatty acids, were prepared by vigorous stirring using a high-speed homogenizer and subsequent freeze-drying. To confirm the anti-inflammatory properties and ulcerogenic effects of the formulations, we examined the action of the formulations on carrageenan-induced edema in rats as well as their ulcerogenic actions in the same species. Compared with IND alone, albumin-IND-olive oil (9:1:4.3), albumin-IND-linolenic acid (9:1:4.3), albumin-IND-linolic acid (9:1:4.3), albumin-IND-oleic acid (9:1:4.3), albumin-IND-stearic acid (9:1:4.3), and albumin-IND-tristearin (9:1:4.3) formulations all exhibited a more potent inhibitory effect on carrageenan-induced edema. In addition, the inhibitory effects on edema formation of an albumin-IND (9:1) complex was as strong as that of IND alone. These results suggested that the bioavailability of IND was increased by olive oil, fatty acid, and tristearin as absorbefacient agents. The increase in the bioavailability was evident from the fact that the mean plasma levels, maximum plasma levels (Cmax), and area under plasma concentration-time curve (AUC) values after oral administration of the albumin-IND-olive oil (9:1:4.3) formulation was significantly greater than that after administration of the drug alone. With respect to their ulcerogenic properties, the formulations were significantly less active than IND alone, suggesting that a reduction in the ulcerogenic activity of IND was by produced complexation with egg albumin.

  15. Metilfenidato e aprimoramento cognitivo farmacológico: representações sociais de universitários Methylphenidate and pharmacological cognitive enhancement: social representations of university students

    Directory of Open Access Journals (Sweden)

    Denise Barros

    2011-06-01

    Full Text Available O artigo tem por objetivo apresentar o resultado da investigação das representações sociais de 20 estudantes universitários sobre o uso de metilfenidato para aprimorar o desempenho cognitivo em pessoas saudáveis. Nesta pesquisa qualitativa, de cunho exploratório, 20 universitários entre 18 e 25 anos, oriundos de cursos das áreas de saúde e humanas, foram distribuídos em três grupos focais para debater sobre o Aprimoramento Cognitivo Farmacológico. A análise dos dados revelou que entre esses estudantes houve uma maior tolerância aos métodos que alteram a neurobiologia a favor do ideal social de melhoria da performance das pessoas. Contudo, os entrevistados expressaram grande preocupação com a possibilidade de este procedimento vir a intensificar injustiças e desigualdades entre as pessoas, principalmente nas sociedades em que já existem significativas diferenças sociais. Assim, apesar de o tema ser pouco estudado no Brasil, a análise dos dados da presente investigação sugere que o Aprimoramento Cognitivo Farmacológico é um assunto atual e relevante. Não apenas por esta prática estar relacionada à construção e manutenção da subjetividade dos indivíduos em uma sociedade que prioriza a melhoria da performance cognitiva, mas também pelo risco de esta interferir em questões de igualdade e justiça social.The article aims to present the outcome of the investigation of social representations of 20 university students on the use of methylphenidate to improve cognitive performance in healthy people. In this qualitative and exploratory research, 20 university students between 18 and 25 years from health and humanities courses were divided into 3 focus groups to discuss about Pharmacological Cognitive Enhancement. Data analysis revealed that these students had greater tolerance to methods that alter neurobiology in favor of the social ideal of improving the performance of people. However, respondents expressed great

  16. gamma-Aminobutyric acid esters. 2. Synthesis, brain uptake, and pharmacological properties of lipid esters of gamma-aminobutyric acid.

    Science.gov (United States)

    Jacob, J N; Shashoua, V E; Campbell, A; Baldessarini, R J

    1985-01-01

    Two lipid esters of U-14C-labeled and unlabeled gamma-aminobutyric acid (GABA) were synthesized to test the possibility that natural lipid analogues, which resemble normal components of lipid bilayer membranes, can penetrate the blood-brain barrier and transport exogenous GABA to the brain. The uptake of 1-linolenoyl-2,3-bis(4-aminobutyryl)propane-1,2,3-triol and 1,2-dilinolenoyl-3-(4-aminobutyryl)propane-1,2,3-triol into mouse brain relative to liver was found to be, respectively, 75- and 127-fold greater than that of free GABA. The results indicate that there is little or no blood-brain barrier for the GABA ester molecules at doses up to 0.36 mmol/kg. Both ester compounds, but neither free GABA nor the lipid components delivered systemically, demonstrated central nervous system depressant properties by inhibiting the general motor activity of mice. Brain tissue has esterase activity which can release GABA from these compounds. This suggests that these compounds function as "prodrugs" to release GABA in the CNS.

  17. Diversity of Pharmacological Properties in Chinese and European Medicinal Plants: Cytotoxicity, Antiviral and Antitrypanosomal Screening of 82 Herbal Drugs

    Directory of Open Access Journals (Sweden)

    Thomas Efferth

    2011-09-01

    Full Text Available In an extensive screening, the antiviral, antitrypanosomal and anticancer properties of extracts from 82 plants used in traditional Chinese medicine and European phytomedicine were determined. Several promising plants that were highly effective against hepatitis B virus (HBV, bovine viral diarrhoea virus (BVDV—a flavivirus used here as a surrogate in vitro model of hepatitis C virus, trypanosomes (Trypanosoma brucei brucei and several cancer cell lines were identified. Six aqueous extracts from Celosia cristata, Ophioglossum vulgatum, Houttuynia cordata, Selaginella tamariscina, Alpinia galanga and Alpinia oxyphylla showed significant antiviral effects against BVDV without toxic effects on host embryonic bovine trachea (EBTr cells, while Evodia lepta, Hedyotis diffusa and Glycyrrhiza spp. demonstrated promising activities against the HBV without toxic effects on host human hepatoblastoma cells transfected with HBV-DNA (HepG2 2.2.15 cells. Seven organic extracts from Alpinia oxyphylla, Coptis chinensis, Kadsura longipedunculata, Arctium lappa, Panax ginseng, Panax notoginseng and Saposhnikovia divaricata inhibited T. b. brucei. Moreover, among fifteen water extracts that combined high antiproliferative activity (IC50 0.5–20 µg/mL and low acute in vitro toxicity (0–10% reduction in cell viability at IC50, Coptis chinensis presented the best beneficial characteristics. In conclusion, traditional herbal medicine from Europe and China still has a potential for new therapeutic targets and therapeutic applications.

  18. Unraveling the Proteome Composition and Immuno-profiling of Western India Russell's Viper Venom for In-Depth Understanding of Its Pharmacological Properties, Clinical Manifestations, and Effective Antivenom Treatment.

    Science.gov (United States)

    Kalita, Bhargab; Patra, Aparup; Mukherjee, Ashis K

    2017-02-03

    The proteome composition of western India (WI) Russell's viper venom (RVV) was correlated with pharmacological properties and pathological manifestations of RV envenomation. Proteins in the 5-19 and 100-110 kDa mass ranges were the most predominate (∼35.1%) and least abundant (∼3.4%) components, respectively, of WI RVV. Non-reduced SDS-PAGE indicated the occurrence of multiple subunits, non-covalent oligomers, self-aggregation, and/or interactions among the RVV proteins. A total of 55 proteins belonging to 13 distinct snake venom families were unambiguously identified by ESI-LC-MS/MS analysis. Phospholipase A2 (32.5%) and Kunitz-type serine protease inhibitors (12.5%) represented the most abundant enzymatic and non-enzymatic proteins, respectively. However, ATPase, ADPase, and hyaluronidase, detected by enzyme assays, were not identified by proteomic analysis owing to limitations in protein database deposition. Several biochemical and pharmacological properties of WI RVV were also investigated. Neurological symptoms exhibited by some RV-bite patients in WI may be correlated to the presence of neurotoxic phospholipase A2 enzymes and Kunitz-type serine protease inhibitor complex in this venom. Monovalent antivenom was found to be better than polyvalent antivenom in immuno-recognition and neutralization of the tested pharmacological properties and enzyme activities of WI RVV; nevertheless, both antivenoms demonstrated poor cross-reactivity and neutralization of pharmacological activities shown by low-molecular-mass proteins (<18 kDa) of this venom.

  19. On the use of slow light for enhancing waveguide properties

    DEFF Research Database (Denmark)

    Mørk, Jesper; Nielsen, Torben Roland

    2010-01-01

    On the basis of a general analysis of waveguides containing a dispersive material, we identify conditions under which slow-light propagation may enhance the gain, absorption, or phase change. The enhancement is shown to depend on the slow-light mechanism and the translational symmetry...... of the waveguide. A combination of material and waveguide dispersion may strongly enhance the control of light speed, e.g., using electromagnetically induced transparency in quantum dots embedded in a photonic crystal waveguide....

  20. Phyto-constituents, Pharmacological Properties and Biotechnological Approaches for Conservation of the Anti-diabetic Functional Food Medicinal Plant Salacia: A Review Note

    Directory of Open Access Journals (Sweden)

    Majid Bagnazari

    2017-01-01

    Full Text Available Background and Objective: Genus Salacia L. (Celastraceae is a woody climbing medicinal plant consisting of about 200 species with many endangered species located throughout the world’s tropical areas. Various parts of the plant as food, functional food additive and tea have been extensively used to treat a variety of ailments like diabetes and obesity as well as inflammatory and skin diseases. The present work reviews the phytochemical properties, pharmacological activities, biotechnological strategy for conservation and safety evaluation of this valuable genus.Results and Conclusion: More efforts are needed to isolate new phytoconstituents from this important medicinal plant. The  echanism of anti-diabetic action has not been done at molecular and cellular levels, thus the fundamental biological understanding is required for future applications. Though the safety of plant species has been well documented and has been confirmed by many toxicological studies, further toxicity research and clinical trials arerecommended. In order to sustain harvest and conservation, agronomic practices for cultivation have to be developed. Establishment of more efficient protocols for in vitro propagation is necessary too. Approaches like genetic manipulation, hairy root culture, media standardization, and use of inducers/precursors for elevation of secondary metabolite levels could also be attractive.Conflict of interest: The authors report no conflicts of interest.

  1. Current knowledge of Schisandra chinensis (Turcz.) Baill. (Chinese magnolia vine) as a medicinal plant species: a review on the bioactive components, pharmacological properties, analytical and biotechnological studies.

    Science.gov (United States)

    Szopa, Agnieszka; Ekiert, Radosław; Ekiert, Halina

    2017-01-01

    Schisandra chinensis Turcz. (Baill.) is a plant species whose fruits have been well known in Far Eastern medicine for a long time. However, schisandra seems to be a plant still underestimated in contemporary therapy still in the countries of East Asia. The article presents latest available information on the chemical composition of this plant species. Special attention is given to dibenzo cyclooctadiene lignans. In addition, recent studies of the biological activity of dibenzocyclooctadiene lignans and schisandra fruit extracts are recapitulated. The paper gives a short resume of their beneficial effects in biological systems in vitro, in animals, and in humans, thus underlining their medicinal potential. The cosmetic properties are depicted, too. The analytical methods used for assaying schisandra lignans in the scientific studies and also in industry are also presented. Moreover, special attention is given to the information on the latest biotechnological studies of this plant species. The intention of this review is to contribute to a better understanding of the huge potential of the pharmacological relevance of S. chinensis.

  2. The Concise Guide to PHARMACOLOGY 2015/16: Overview

    National Research Council Canada - National Science Library

    ...; Alexander, Stephen PH; Kelly, Eamonn; Marrion, Neil; Peters, John A; Benson, Helen E; Faccenda, Elena; Pawson, Adam J; Sharman, Joanna L; Southan, Christopher; Buneman, O Peter; Catterall, William A; Cidlowski, John A; Davenport, Anthony P; Fabbro, Doriano; Fan, Grace; McGrath, John C; Spedding, Michael; Davies, Jamie A; Aldrich, R; Attali, B; Bäck, Ml; Barnes, NM; Bathgate, R; Beart, PM; Becirovic, E; Biel, M; Birdsall, NJ; Boison, D; Bräuner‐Osborne, H; Bröer, S; Bryant, C; Burnstock, G; Burris, T; Cain, D; Calo, G; Chan, SL; Chandy, KG; Chiang, N; Christakos, S; Christopoulos, A; Chun, JJ; Chung, J‐J; Clapham, DE; Connor, MA; Coons, L; Cox, HM; Dautzenberg, FM; Dent, G; Douglas, SD; Dubocovich, ML; Edwards, DP; Farndale, R; Fong, TM; Forrest, D; Fowler, CJ; Fuller, P; Gainetdinov, RR; Gershengorn, MA; Goldin, A; Goldstein, SAN; Grimm, SL; Grissmer, S; Gundlach, AL; Hagenbuch, B; Hammond, JR; Hancox, JC; Hartig, S; Hauger, RL; Hay, DL; Hébert, T; Hollenberg, AN; Holliday, ND; Hoyer, D; Ijzerman, AP; Inui, KI; Ishii, S; Jacobson, KA; Jan, LY; Jarvis, GE; Jensen, R; Jetten, A; Jockers, R; Kaczmarek, LK; Kanai, Y; Kang, HS; Karnik, S; Kerr, ID; Korach, KS; Lange, CA; Larhammar, D; Leeb‐Lundberg, F; Leurs, R; Lolait, SJ; Macewan, D; Maguire, JJ; May, JM; Mazella, J; Mcardle, CA; Mcdonnell, DP; Michel, MC

    2015-01-01

    The Concise Guide to PHARMACOLOGY 2015/16 provides concise overviews of the key properties of over 1750 human drug targets with their pharmacology, plus links to an open access knowledgebase of drug...

  3. Chemotaxonomy and pharmacology of Gentianaceae

    DEFF Research Database (Denmark)

    Jensen, Søren Rosendal; Schripsema, Jan

    2002-01-01

    the remaining six are members of the Gentianeae. Based on the above results, a tentative list of chemical characteristics for the tribes of the Gentianaceae is presented. Finally, some pharmacologically interesting properties of plant extracts or compounds from taxa within Gentianaceae are listed....

  4. Pharmacology of Marihuana (Cannabis sativa)

    Science.gov (United States)

    Maickel, Roger P.

    1973-01-01

    A detailed discussion of marihuana (Cannabis sativa) providing the modes of use, history, chemistry, and physiologic properties of the drug. Cites research results relating to the pharmacologic effects of marihuana. These effects are categorized into five areas: behavioral, cardiovascular-respiratory, central nervous system, toxicity-toxicology,…

  5. Pharmacologic overview of Withania somnifera, the Indian Ginseng.

    Science.gov (United States)

    Dar, Nawab John; Hamid, Abid; Ahmad, Muzamil

    2015-12-01

    Withania somnifera, also called 'Indian ginseng', is an important medicinal plant of the Indian subcontinent. It is widely used, singly or in combination, with other herbs against many ailments in Indian Systems of Medicine since time immemorial. Withania somnifera contains a spectrum of diverse phytochemicals enabling it to have a broad range of biological implications. In preclinical studies, it has shown anti-microbial, anti-inflammatory, anti-tumor, anti-stress, neuroprotective, cardioprotective, and anti-diabetic properties. Additionally, it has demonstrated the ability to reduce reactive oxygen species, modulate mitochondrial function, regulate apoptosis, and reduce inflammation and enhance endothelial function. In view of these pharmacologic properties, W. somnifera is a potential drug candidate to treat various clinical conditions, particularly related to the nervous system. In this review, we summarize the pharmacologic characteristics and discuss the mechanisms of action and potential therapeutic applications of the plant and its active constituents.

  6. Proteomic analysis to unravel the complex venom proteome of eastern India Naja naja: Correlation of venom composition with its biochemical and pharmacological properties.

    Science.gov (United States)

    Dutta, Sumita; Chanda, Abhishek; Kalita, Bhargab; Islam, Taufikul; Patra, Aparup; Mukherjee, Ashis K

    2017-03-06

    The complex venom proteome of the eastern India (EI) spectacled cobra (Naja naja) was analyzed using tandem mass spectrometry of cation-exchange venom fractions. About 75% of EI N. naja venom proteins were naja venom with a percent composition of about 28.4% and 71.6% respectively were distributed over 15 venom protein families. The three finger toxins (63.8%) and phospholipase A2s (11.4%) were the most abundant families of non-enzymatic and enzymatic proteins, respectively. nanoLC-ESI-MS/MS analysis demonstrated the occurrence of acetylcholinesterase, phosphodiesterase, cholinesterase and snake venom serine proteases in N. naja venom previously not detected by proteomic analysis. ATPase, ADPase, hyaluronidase, TAME, and BAEE-esterase activities were detected by biochemical analysis; however, due to a limitation in the protein database depository they were not identified in EI N. naja venom by proteomic analysis. The proteome composition of EI N. naja venom was well correlated with its in vitro and in vivo pharmacological properties in experimental animals and envenomed human. Proteomic analysis reveals the complex and diverse protein profile of EI N. naja venom which collectively contributes to the severe pathophysiological manifestation upon cobra envenomation. The study has also aided in comprehending the compositional variation in venom proteins of N. naja within the Indian sub-continent. In addition, this study has also identified several enzymes in EI N. naja venom which were previously uncharacterized by proteomic analysis of Naja venom. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Interaction of nilotinib, dasatinib and bosutinib with ABCB1 and ABCG2: implications for altered anti-cancer effects and pharmacological properties.

    Science.gov (United States)

    Hegedus, C; Ozvegy-Laczka, C; Apáti, A; Magócsi, M; Német, K; Orfi, L; Kéri, G; Katona, M; Takáts, Z; Váradi, A; Szakács, G; Sarkadi, B

    2009-10-01

    ABC multidrug transporters (MDR-ABC proteins) cause multiple drug resistance in cancer and may be involved in the decreased anti-cancer efficiency and modified pharmacological properties of novel specifically targeted agents. It has been documented that ABCB1 and ABCG2 interact with several first-generation, small-molecule, tyrosine kinase inhibitors (TKIs), including the Bcr-Abl fusion kinase inhibitor imatinib, used for the treatment of chronic myeloid leukaemia. Here, we have investigated the specific interaction of these transporters with nilotinib, dasatinib and bosutinib, three clinically used, second-generation inhibitors of the Bcr-Abl tyrosine kinase activity. MDR-ABC transporter function was screened in both membrane- and cell-based (K562 cells) systems. Cytotoxicity measurements in Bcr-Abl-positive model cells were coupled with direct determination of intracellular TKI concentrations by high-pressure liquid chromatography-mass spectrometry and analysis of the pattern of Bcr-Abl phosphorylation. Transporter function in membranes was assessed by ATPase activity. Nilotinib and dasatinib were high-affinity substrates of ABCG2, and this protein mediated an effective resistance in cancer cells against these compounds. Nilotinib and dasatinib also interacted with ABCB1, but this transporter provided resistance only against dasatinib. Neither ABCB1 nor ABCG2 induced resistance to bosutinib. At relatively higher concentrations, however, each TKI inhibited both transporters. A combination of in vitro assays may provide valuable preclinical information for the applicability of novel targeted anti-cancer TKIs, even in multidrug-resistant cancer. The pattern of MDR-ABC transporter-TKI interactions may also help to understand the general pharmacokinetics and toxicities of new TKIs.

  8. Interaction of nilotinib, dasatinib and bosutinib with ABCB1 and ABCG2: implications for altered anti-cancer effects and pharmacological properties

    Science.gov (United States)

    Hegedűs, C; Özvegy-Laczka, C; Apáti, Á; Magócsi, M; Német, K; Őrfi, L; Kéri, G; Katona, M; Takáts, Z; Váradi, A; Szakács, G; Sarkadi, B

    2009-01-01

    Background and purpose: ABC multidrug transporters (MDR-ABC proteins) cause multiple drug resistance in cancer and may be involved in the decreased anti-cancer efficiency and modified pharmacological properties of novel specifically targeted agents. It has been documented that ABCB1 and ABCG2 interact with several first-generation, small-molecule, tyrosine kinase inhibitors (TKIs), including the Bcr-Abl fusion kinase inhibitor imatinib, used for the treatment of chronic myeloid leukaemia. Here, we have investigated the specific interaction of these transporters with nilotinib, dasatinib and bosutinib, three clinically used, second-generation inhibitors of the Bcr-Abl tyrosine kinase activity. Experimental approach: MDR-ABC transporter function was screened in both membrane- and cell-based (K562 cells) systems. Cytotoxicity measurements in Bcr-Abl-positive model cells were coupled with direct determination of intracellular TKI concentrations by high-pressure liquid chromatography-mass spectrometry and analysis of the pattern of Bcr-Abl phosphorylation. Transporter function in membranes was assessed by ATPase activity. Key results: Nilotinib and dasatinib were high-affinity substrates of ABCG2, and this protein mediated an effective resistance in cancer cells against these compounds. Nilotinib and dasatinib also interacted with ABCB1, but this transporter provided resistance only against dasatinib. Neither ABCB1 nor ABCG2 induced resistance to bosutinib. At relatively higher concentrations, however, each TKI inhibited both transporters. Conclusions and implications: A combination of in vitro assays may provide valuable preclinical information for the applicability of novel targeted anti-cancer TKIs, even in multidrug-resistant cancer. The pattern of MDR-ABC transporter–TKI interactions may also help to understand the general pharmacokinetics and toxicities of new TKIs. PMID:19785662

  9. Field-enhanced nonlinear optical properties of organic nanofibers

    DEFF Research Database (Denmark)

    Kostiučenko, Oksana; Fiutowski, Jacek; Brewer, Jonathan R.

    2014-01-01

    Second harmonic generation in nonlinearly optically active organic nanofibers, generated via self-assembled surface growth from nonsymmetrically functionalized para-quarterphenylene (CNHP4) molecules, has been investigated. After the growth on mica templates, nanofibers have been transferred onto...... lithographically defined regular arrays of metal and dielectric nanostructures. Such hybrid systems were employed to correlate the second harmonic response to both morphology of the fibers i.e. local field enhancement due to local changes in the fiber’s morphology and field enhancement effects appearing...... on the nanostructures. With the help of femtosecond laser scanning microscopy two-dimensional second-harmonic images of individual nanoaggregates were obtained and analyzed....

  10. Field-enhanced nonlinear optical properties of organic nanofibers

    DEFF Research Database (Denmark)

    Kostiučenko, Oksana; Fiutowski, Jacek; Brewer, Jonathan R.

    Second harmonic generation in nonlinearly optically active organic nanofibers, generated via self-assembled surface growth from nonsymmetrically functionalized para-quarterphenylene (CNHP4) molecules, has been investigated. After the growth on mica templates, nanofibers have been transferred onto...... lithographically defined regular arrays of metal and dielectric nanostructures. Such hybrid systems were employed to correlate the second harmonic response to both morphology of the fibers i.e. local field enhancement due to local changes in the fiber’s morphology and field enhancement effects appearing...... on the nanostructures. With the help of femtosecond laser scanning microscopy two-dimensional second-harmonic images of individual nanoaggregates were obtained and analyzed....

  11. Spherical agglomerates of lactose with enhanced mechanical properties.

    Science.gov (United States)

    Lamešić, Dejan; Planinšek, Odon; Lavrič, Zoran; Ilić, Ilija

    2017-01-10

    The aim of this study was to prepare spherical agglomerates of lactose and to evaluate their physicochemical properties, flow properties, particle friability and compaction properties, and to compare them to commercially available types of lactose for direct compression (spray-dried, granulated and anhydrous β-lactose). Porous spherical agglomerates of α-lactose monohydrate with radially arranged prism-like primary particles were prepared exhibiting a high specific surface area. All types of lactose analysed had passable or better flow properties, except for anhydrous β-lactose, which had poor flowability. Particle friability was more pronounced in larger granulated lactose particles; however, particle structure was retained in all samples analysed. The mechanical properties of spherical agglomerates of lactose, in terms of compressibility, established with Walker analysis, and compactibility, established with a compactibility profile, were found to be superior to any commercially available types of lactose. Higher compactibility of spherical agglomerates of lactose is ascribed to significantly higher particle surface area due to a unique internal structure with higher susceptibility to fragmentation. Copyright © 2016 Elsevier B.V. All rights reserved.

  12. Pharmacological effects of rosa damascena.

    Science.gov (United States)

    Boskabady, Mohammad Hossein; Shafei, Mohammad Naser; Saberi, Zahra; Amini, Somayeh

    2011-07-01

    Rosa damascena mill L., known as Gole Mohammadi in is one of the most important species of Rosaceae family flowers. R. damascena is an ornamental plant and beside perfuming effect, several pharmacological properties including anti-HIV, antibacterial, antioxidant, antitussive, hypnotic, antidiabetic, and relaxant effect on tracheal chains have been reported for this plant. This article is a comprehensive review on pharmacological effects of R. damascena. Online literature searches were performed using Medline, medex, Scopus, and Google Scholar websites backed to 1972 to identify researches about R. damascena. Searches also were done by going through the author's files and the bibliographies of all located papers.

  13. Cognitive-enhancing properties of Morinda lucida (Rubiaceae) and ...

    African Journals Online (AJOL)

    This study evaluated the cognitive enhancing potentials of Morinda lucida (L) Rubiaceae and Peltophorum pterocarpum (DC) ex. K Heyne in scopolamine induced amnesic animals. Materials and Methods: The anti-amnesic activity of the ethyl acetate extracts of Morinda lucida and Peltophorum pterocarpum at doses of 4 ...

  14. Enhanced physicochemical properties of collagen by using EDC ...

    Indian Academy of Sciences (India)

    Home; Journals; Bulletin of Materials Science; Volume 35; Issue 5. Enhanced ... Collagen-based scaffolds are appealing products for the repair of cartilage defects using tissue engineering strategies. The present ... Department of Materials Science and Engineering, Fujian University of Technology, Fuzhou 350108, China ...

  15. Superfocusing properties of disorder-enhanced plasmonic nanolenses

    KAUST Repository

    Gongora, J. S. Totero

    2014-01-01

    We investigated a disordered plasmonic nanolens using an extensive campaign of FDTD simulations. Our results show that surface roughness plays a crucial role in the enhancement of the electromagnetic energy with respect to regular structures. © 2014 Optical Society of America.

  16. Fabrication and enhanced photoluminescence properties of NaLa ...

    Indian Academy of Sciences (India)

    2017-08-29

    Aug 29, 2017 ... Many phosphors have been applied on white. LED, such as a yellow emitting phosphor Y3Al5O12: Ce3+,. YAG: Ce3+ based on blue InGaN LED [29]. It is necessary to add a red component to enhance the colour rendering index. Therefore, researches on high efficiency red phos- phors are very important.

  17. Membranes with Surface-Enhanced Antifouling Properties for Water Purification

    Directory of Open Access Journals (Sweden)

    Nima Shahkaramipour

    2017-03-01

    Full Text Available Membrane technology has emerged as an attractive approach for water purification, while mitigation of fouling is key to lower membrane operating costs. This article reviews various materials with antifouling properties that can be coated or grafted onto the membrane surface to improve the antifouling properties of the membranes and thus, retain high water permeance. These materials can be separated into three categories, hydrophilic materials, such as poly(ethylene glycol, polydopamine and zwitterions, hydrophobic materials, such as fluoropolymers, and amphiphilic materials. The states of water in these materials and the mechanisms for the antifouling properties are discussed. The corresponding approaches to coat or graft these materials on the membrane surface are reviewed, and the materials with promising performance are highlighted.

  18. Membranes with Surface-Enhanced Antifouling Properties for Water Purification

    Science.gov (United States)

    Shahkaramipour, Nima; Tran, Thien N.; Ramanan, Sankara; Lin, Haiqing

    2017-01-01

    Membrane technology has emerged as an attractive approach for water purification, while mitigation of fouling is key to lower membrane operating costs. This article reviews various materials with antifouling properties that can be coated or grafted onto the membrane surface to improve the antifouling properties of the membranes and thus, retain high water permeance. These materials can be separated into three categories, hydrophilic materials, such as poly(ethylene glycol), polydopamine and zwitterions, hydrophobic materials, such as fluoropolymers, and amphiphilic materials. The states of water in these materials and the mechanisms for the antifouling properties are discussed. The corresponding approaches to coat or graft these materials on the membrane surface are reviewed, and the materials with promising performance are highlighted. PMID:28273869

  19. Enhancing the functional properties and nutritional quality of ice cream with processed amla (Indian gooseberry)

    National Research Council Canada - National Science Library

    Goraya, Rajpreet Kaur; Bajwa, Usha

    2015-01-01

    .... In contrast, ice cream is a poor source of these phytochemicals and antioxidants; therefore, the present investigation was undertaken to enhance the functional properties and nutritional quality of ice cream with the incorporation of processed amla...

  20. Fabrication and enhanced photoluminescence properties of NaLa ...

    Indian Academy of Sciences (India)

    Furthermore,UV-absorption and the photoluminescence (PL) properties of these phosphors were systematically investigated and the PLof the phosphors shows strong white light emissions. Efficient energy transfer from the MoO 4 2 − group or Bi 3 + ions to Sm 3 + ions was established by PL investigation excited at 405 nm.

  1. Enhanced physicochemical properties of collagen by using EDC ...

    Indian Academy of Sciences (India)

    Introduction. The necessity of bone substitutes for wound healing has promoted development of the biomimetic bone biomateri- als. Collagen, therefore, becomes a popular biomaterial for this purpose due to its compatibility. The desired properties of collagen which facilitates wound-healing processes are stimulation of cell ...

  2. Experimental Enhancement for Electric Properties of Polyethylene Nanocomposites under Thermal Conditions

    Directory of Open Access Journals (Sweden)

    Ahmed Thabet

    2017-01-01

    Full Text Available Polymer properties can be experimentally tailored by adding small amounts of different nanoparticles for enhancing their mechanical, thermal and electrical properties. The work in this paper investigates enhancing the electric and dielectric properties of Low Density Polyethylene (LDPE, and High Density Polyethylene (HDPE polymer materials with cheap nanoparticles. Certain percentages of clay and fumed silica nanoparticles are used to enhance electric and dielectric properties of polyethylene nanocomposites films. By using the Dielectric Spectroscopy; the electric and dielectric properties of each polyethylene nanocomposites have been measured with and without nanoparticles at various frequencies up to 1kHz under different thermal conditions (20°C and 60°C. And so, we were successful in specifying the optimal nanoparticles types and their concentrations for the control of electric and dielectric characterization.

  3. Real-time observations of mechanical stimulus-induced enhancements of mechanical properties in osteoblast cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Xu; Liu Xiaoli; Sun Jialun [State Key Laboratory of Bioactive Materials, School of Physics, Nankai University, Tianjin 300073 (China); He Shuojie [State Key Laboratory of Bioactive Materials, School of Physics, Nankai University, Tianjin 300073 (China); Department of Physics, Pusan National University, Pusan (Korea, Republic of); Lee, Imshik [State Key Laboratory of Bioactive Materials, School of Physics, Nankai University, Tianjin 300073 (China)], E-mail: ilee@nankai.edu.cn2; Pak, Hyuk Kyu [Department of Physics, Pusan National University, Pusan (Korea, Republic of)

    2008-09-15

    Osteoblast, playing a key role in the pathophysiology of osteoporosis, is one of the mechanical stress sensitive cells. The effects of mechanical load-induced changes of mechanical properties in osteoblast cells were studied at real-time. Osteoblasts obtained from young Wister rats were exposed to mechanical loads in different frequencies and resting intervals generated by atomic force microscopy (AFM) probe tip and simultaneously measured the changes of the mechanical properties by AFM. The enhancement of the mechanical properties was observed and quantified by the increment of the apparent Young's modulus, E{sup *}. The observed mechanical property depended on the frequency of applied tapping loads. For the resting interval is 50 s, the mechanical load-induced enhancement of E{sup *}-values disappears. It seems that the enhanced mechanical property was recover able under no additional mechanical stimulus.

  4. ENHANCING OF WOOD CHIPPING CONCRETE PROPERTIES BY ADDING WASTE FIBRE

    Directory of Open Access Journals (Sweden)

    Fadia S. Kulak

    2013-05-01

    Full Text Available The recycling of wood chippings, anindustrial waste product, has a potential use in the production of alightweight concrete. In modern countries, the low cost and the proximity ofsupply makes this material a good candidate for local building applications.This study aims to examining the ability of enhancing of a wood fibre lightweightconcrete strength by reinforcing it with lathe scrap from lathe industry. Specimenshave been casted, compressive and split tensile strengths were measured inaddition to the wet and dry weight as per relevant British standardspecifications. The wood chippings are saturated with a water for 24 hours,this is to prevent chippings from sorption the water of the mixture. Testresults indicate that addition of waste fibre from lathe enhances the strengthmarkedly and in the same time increases the weight.

  5. Pharmacological activities and pharmacokinetic study of hyperoside ...

    African Journals Online (AJOL)

    ... with no significant gender variation in its activities. Other significant details on its pharmacological properties and information for future investigations on its components are provided. Keywords: Hyperoside; Anti-inflammatory, Antidepressant, Neuroprotective, Antidiabetic, Anticancer, Antioxidant, Cytochrome P450 ...

  6. Phytochemistry, pharmacology and ethnomedicinal uses of Ficus ...

    African Journals Online (AJOL)

    Blume moraceae): A review. ... Ficus thonningii contains various bioactive compounds which include alkaloids, terpenoids, flavonoids, tannins and active proteins, all of which contribute to its curative properties. In vitro and in vivo pharmacological ...

  7. Phytochemical and pharmacological overview on Liriopes radix

    African Journals Online (AJOL)

    and pharmacological activities in vitro and in vivo. The review does not ... inflammation, airway inflammation, obesity, and diabetes [1]. ... content, chemical, and physical properties. Many ..... A strong luciferase signal detected in the abdominal ...

  8. Enhancement of Hevea brasiliensis properties through chemical application.

    Science.gov (United States)

    Kadir, Roszaini; Jantan, Mohd D

    2016-01-01

    The effects of four different types of bleaching agents (hydrogen peroxide, sodium hypochlorite, sodium chlorite and oxalic acid) mixed together with 2% boron-based preservative (Celbor SP) were studied on green sawn rubberwood. Two concentration levels (1% and 2%) of were used. Whitish values (W) and colour changes (ΔE) of sawn rubberwood were assessed before and after chemical treatment using a colour meter. Preliminary observation indicated that timber treated with 1% and 2% hydrogen peroxide produced better and more homogeneous colour properties. Hydrogen peroxide treated timber gave higher whitish values (6.23 and 9.91 for 1% and 2% solution, respectively) and lower colour changes (8.49 and 5.51 for 1% and 2% solution, respectively) when compared to the other three chemicals. Evaluation on the effects of bleaching (hydrogen peroxide with a higher level of concentration) on physical, mechanical and biological properties of rubberwood also have been determined in this study.

  9. Enhancement of Hevea brasiliensis properties through chemical application

    Directory of Open Access Journals (Sweden)

    ROSZAINI KADIR

    Full Text Available ABSTRACT The effects of four different types of bleaching agents (hydrogen peroxide, sodium hypochlorite, sodium chlorite and oxalic acid mixed together with 2% boron-based preservative (Celbor SP were studied on green sawn rubberwood. Two concentration levels (1% and 2% of were used. Whitish values (W and colour changes (ΔE of sawn rubberwood were assessed before and after chemical treatment using a colour meter. Preliminary observation indicated that timber treated with 1% and 2% hydrogen peroxide produced better and more homogeneous colour properties. Hydrogen peroxide treated timber gave higher whitish values (6.23 and 9.91 for 1% and 2% solution, respectively and lower colour changes (8.49 and 5.51 for 1% and 2% solution, respectively when compared to the other three chemicals. Evaluation on the effects of bleaching (hydrogen peroxide with a higher level of concentration on physical, mechanical and biological properties of rubberwood also have been determined in this study.

  10. Pharmacological inhibition of caspase and calpain proteases: a novel strategy to enhance the homing responses of cord blood HSPCs during expansion.

    Directory of Open Access Journals (Sweden)

    V M Sangeetha

    Full Text Available BACKGROUND: Expansion of hematopoietic stem/progenitor cells (HSPCs is a well-known strategy employed to facilitate the transplantation outcome. We have previously shown that the prevention of apoptosis by the inhibition of cysteine proteases, caspase and calpain played an important role in the expansion and engraftment of cord blood (CB derived HSPCs. We hypothesize that these protease inhibitors might have maneuvered the adhesive and migratory properties of the cells rendering them to be retained in the bone marrow for sustained engraftment. The current study was aimed to investigate the mechanism of the homing responses of CB cells during expansion. METHODOLOGY/PRINCIPAL FINDINGS: CB derived CD34(+ cells were expanded using a combination of growth factors with and without Caspase inhibitor -zVADfmk or Calpain 1 inhibitor- zLLYfmk. The cells were analyzed for the expression of homing-related molecules. In vitro adhesive/migratory interactions and actin polymerization dynamics of HSPCs were assessed. In vivo homing assays were carried out in NOD/SCID mice to corroborate these observations. We observed that the presence of zVADfmk or zLLYfmk (inhibitors caused the functional up regulation of CXCR4, integrins, and adhesion molecules, reflecting in a higher migration and adhesive interactions in vitro. The enhanced actin polymerization and the RhoGTPase protein expression complemented these observations. Furthermore, in vivo experiments showed a significantly enhanced homing to the bone marrow of NOD/SCID mice. CONCLUSION/SIGNIFICANCE: Our present study reveals another novel aspect of the regulation of caspase and calpain proteases in the biology of HSPCs. The priming of the homing responses of the inhibitor-cultured HSPCs compared to the cytokine-graft suggests that the modulation of these proteases may help in overcoming the major homing defects prevalent in the expansion cultures thereby facilitating the manipulation of cells for transplant

  11. Enhanced properties of graphene/fly ash geopolymeric composite cement

    Energy Technology Data Exchange (ETDEWEB)

    Saafi, Mohamed, E-mail: m.bensalem.saafi@strath.ac.uk [Department of Civil and Environmental Engineering, University of Strathclyde, G4 0NG (United Kingdom); Tang, Leung [Agilent Technologies, EH12 9DJ (United Kingdom); Fung, Jason; Rahman, Mahbubur [Department of Civil and Environmental Engineering, University of Strathclyde, G4 0NG (United Kingdom); Liggat, John [Department of Pure and Applied Chemistry, University of Strathclyde, G4 0NG (United Kingdom)

    2015-01-15

    This paper reports for the first time the incorporation of in-situ reduced graphene oxide (rGO) into geopolymers. The resulting rGO–geopolymeric composites are easy to manufacture and exhibit excellent mechanical properties. Geopolymers with graphene oxide (GO) concentrations of 0.00, 0.10, 0.35 and 0.50% by weight were fabricated. The functional groups, morphology, void filling mechanisms and mechanical properties of the composites were determined. The Fourier transform infrared (FTIR) spectra revealed that the alkaline solution reduced the hydroxyl/carbonyl groups of GO by deoxygenation and/or dehydration. Concomitantly, the spectral absorbance related to silica type cross-linking increased in the spectra. The scanning electron microscope (SEM) micrographs indicated that rGO altered the morphology of geopolymers from a porous nature to a substantially pore filled morphology with increased mechanical properties. The flexural tests showed that 0.35-wt.% rGO produced the highest flexural strength, Young's modulus and flexural toughness and they were increased by 134%, 376% and 56%, respectively.

  12. Enhancing antibacterial properties of UHMWPE via ion implantation

    Science.gov (United States)

    Nassisi, Vincenzo; Delle Side, Domenico; Velardi, Luciano; Alifano, Pietro; Talà, Adelfia; Maurizio Tredici, Salvatore

    2012-10-01

    In the last decades, the demand for biomaterials of antimicrobial quality sensibly increased. The essential properties of these materials must be the biocompatibility, wettability, durability and their antibacterial characteristics. One of the most important biomaterial for medical applications is the ultra high molecular weight polyethylene (UHMWPE) that it is used to make components of prosthetic knee, hip and shoulder. It is well known that the presence in UHMWPE of Ag atoms increase its antibacterial properties while Cu and its alloys are known as natural antimicrobial materials. In this work it is proposed a dedicated laser ion source (LIS) accelerator to perform ion implantation together with a systematic study of the surface properties of UHMWPE samples treated with different metals in order to modify their antibacterial characteristics. The proposed technique consists in the application of a dose of specific ions inside the first layer of the sample to be treated. This goal can be effectively achieved if the ions are preventively accelerated. This technique seems to be interesting, since it can open the way to an easier realization of antibacterial materials using various metal ions.

  13. Nanoparticle Properties and Synthesis Effects on Surface-Enhanced Raman Scattering Enhancement Factor: An Introduction

    Directory of Open Access Journals (Sweden)

    Nathan D. Israelsen

    2015-01-01

    Full Text Available Raman spectroscopy has enabled researchers to map the specific chemical makeup of surfaces, solutions, and even cells. However, the inherent insensitivity of the technique makes it difficult to use and statistically complicated. When Raman active molecules are near gold or silver nanoparticles, the Raman intensity is significantly amplified. This phenomenon is referred to as surface-enhanced Raman spectroscopy (SERS. The extent of SERS enhancement is due to a variety of factors such as nanoparticle size, shape, material, and configuration. The choice of Raman reporters and protective coatings will also influence SERS enhancement. This review provides an introduction to how these factors influence signal enhancement and how to optimize them during synthesis of SERS nanoparticles.

  14. Enhancement of Unequal Error Protection Properties of LDPC Codes

    Directory of Open Access Journals (Sweden)

    Poulliat Charly

    2007-01-01

    Full Text Available It has been widely recognized in the literature that irregular low-density parity-check (LDPC codes exhibit naturally an unequal error protection (UEP behavior. In this paper, we propose a general method to emphasize and control the UEP properties of LDPC codes. The method is based on a hierarchical optimization of the bit node irregularity profile for each sensitivity class within the codeword by maximizing the average bit node degree while guaranteeing a minimum degree as high as possible. We show that this optimization strategy is efficient, since the codes that we optimize show better UEP capabilities than the codes optimized for the additive white Gaussian noise channel.

  15. Nanoscale chemical interaction enhances the physical properties of bioglass composites.

    Science.gov (United States)

    Ravarian, Roya; Zhong, Xia; Barbeck, Mike; Ghanaati, Shahram; Kirkpatrick, Charles James; Murphy, Ciara M; Schindeler, Aaron; Chrzanowski, Wojciech; Dehghani, Fariba

    2013-10-22

    Bioglasses are favorable biomaterials for bone tissue engineering; however, their applications are limited due to their brittleness. In addition, the early failure in the interface is a common problem of composites of bioglass and a polymer with high mechanical strength. This effect is due to the phase separation, nonhomogeneous mixture, nonuniform mechanical strength, and different degradation properties of two compounds. To address these issues, in this study a nanoscale interaction between poly(methyl methacrylate) (PMMA) and bioactive glass was formed via silane coupling agent (3-trimethoxysilyl)propyl methacrylate (MPMA). A monolith was produced at optimum composition from this hybrid by the sol-gel method at 50 °C with a rapid gelation time (bioglass and physical mixture. For instance, the Young's modulus of bioglass was decreased 40-fold and the dissolution rate of silica was retarded 1.5-fold by integration of PMMA. Prolonged dissolution of silica fosters bone integration due to the continuous dissolution of bioactive silica. The primary osteoblast cells were well anchored and cell migration was observed on the surface of the hybrid. The in vivo studies in mice demonstrated that the integrity of the hybrids was maintained in subcutaneous implantation. They induced mainly a mononuclear phagocytic tissue reaction with a low level of inflammation, while bioglass provoked a tissue reaction with TRAP-positive multinucleated giant cells. These results demonstrated that the presence of a nanoscale interaction between bioglass and PMMA affects the properties of bioglass and broadens its potential applications for bone replacement.

  16. Thermo-Optical Properties of Colloids Enhanced by Gold Nanoparticles

    Science.gov (United States)

    Aleali, Hoda; Sarkhosh, Leila; Eslamifar, Mina; Karimzadeh, Rouhollah; Mansour, Nastaran

    2010-08-01

    This work presents a study on the thermo-optical properties of colloidal gold nanoparticles (AuNPs) under a low power laser irradiation at 532 nm. Samples of various gold volume fractions, ranging from 2.5×10-4 to 19.5×10-4%, are synthesized by nanosecond pulsed laser ablation of a pure gold plate in the distilled water. The formation of the AuNPs has been evidenced by optical absorption spectra and transmission electron microscopy. We investigate the effect of the gold nanoparticle concentration on thermo-optical properties of the colloids using the Z-scan technique. The nonlinear optical measurements exhibit a very large nonlinear refraction close to the surface plasmon resonance frequency of the nanoparticles. Our results reveal that the heat diffusion in the colloids is due to nonlocal thermal process. As the gold concentration increases, the temperature change within and around gold nanoparticles greatly enlarges the thermo-optic and thermal nonlinear refractive index coefficients of the samples. This work suggests that thermal nonlinear refraction will play an important role in development of photonic applications involving metal nanoparticles colloids.

  17. Innovative phytosynthesized silver nanoarchitectures with enhanced antifungal and antioxidant properties

    Science.gov (United States)

    Ortan, Alina; Fierascu, Irina; Ungureanu, Camelia; Fierascu, Radu Claudiu; Avramescu, Sorin Marius; Dumitrescu, Ovidiu; Dinu-Pirvu, Cristina Elena

    2015-12-01

    While in the early era of nanotechnology, nanoparticles of noble metals were obtained through expensive methods, using toxic chemical reagents, in the last decade attempts are made to obtain the desired chemical composition, size, morphology, and other properties by eco and green synthesis, using plants. The aim of this paper is to compare two extraction methods (hydroalcoholic extraction and microwave extraction) used to phytosynthesize silver nanoparticles, in terms of nanoparticle (NP) morphology, antioxidant, and antifungal action, using an European native plant, Anthriscus cerefolium (L.) Hoffm. The extracts and the obtained NPs were characterized by modern analytical techniques (GC-MS, UV-Vis, SEM, TEM) and by phytochemical assays (total flavonoids, total terpenoids and total phenolic content). The antifungal activity (evaluated using the Kirby-Bauer method, against Aspergillus niger and Penicillium hirsutum) and the antioxidant activity (determined by the DPPH assay and a chemiluminescence assay) revealed notable differences between the samples, differences due to the extraction procedure followed. Also, preliminary studies regarding the stability and the toxicity of the nanoparticles are presented. By using the microwave-assisted extraction, not only smaller particles (less than 10 nm) were obtained, but also with better antifungal and antioxidant properties than the ones obtained by classical extraction.

  18. Dendritic optical antennas: scattering properties and fluorescence enhancement.

    Science.gov (United States)

    Guo, Ke; Antoncecchi, Alessandro; Zheng, Xuezhi; Sallam, Mai; Soliman, Ezzeldin A; Vandenbosch, Guy A E; Moshchalkov, Victor V; Koenderink, A Femius

    2017-07-24

    With the development of nanotechnologies, researchers have brought the concept of antenna to the optical regime for manipulation of nano-scaled light matter interactions. Most optical nanoantennas optimize optical function, but are not electrically connected. In order to realize functions that require electrical addressing, optical nanoantennas that are electrically continuous are desirable. In this article, we study the optical response of a type of electrically connected nanoantennas, which we propose to call "dendritic" antennas. While they are connected, they follow similar antenna hybridization trends to unconnected plasmon phased array antennas. The optical resonances supported by this type of nanoantennas are mapped both experimentally and theoretically to unravel their optical response. Photoluminescence measurements indicate a potential Purcell enhancement of more than a factor of 58.

  19. Nitrogen doped germania glasses with enhanced optical and mechanical properties

    DEFF Research Database (Denmark)

    Storgaard-Larsen, Torben; Poulsen, Christian; Leistiko, Otto

    1997-01-01

    A new type of ultraviolet photosensitive germanium doped glass has been developed for use in the fabrication of optical waveguide structures. By adding ammonia to the source gases during a plasma enhanced chemical vapor deposition of these glasses, ultraviolet induced refractive index changes of up...... to 3.5 x 10(-3) have been obtained. Although this is, to the best of our knowledge, a record for germanium doped silica films not photosensitized by hydrogen loading, our results show that even larger changes in the refractive index can be induced. Stable glasses with refractive indexes from 1.460 to 1.......518 have been formed throughout the composition range from 0 to 30% germanium by including ammonia in the deposition process Not only is it possible to increase the photosensitivity, but it is also possible to control stress in these films. Depending on the deposition and annealing conditions, these glass...

  20. Nanostructured germanium deposited on heated substrates with enhanced photoelectric properties

    Directory of Open Access Journals (Sweden)

    Ionel Stavarache

    2016-10-01

    Full Text Available Obtaining high-quality materials, based on nanocrystals, at low temperatures is one of the current challenges for opening new paths in improving and developing functional devices in nanoscale electronics and optoelectronics. Here we report a detailed investigation of the optimization of parameters for the in situ synthesis of thin films with high Ge content (50 % into SiO2. Crystalline Ge nanoparticles were directly formed during co-deposition of SiO2 and Ge on substrates at 300, 400 and 500 °C. Using this approach, effects related to Ge–Ge spacing are emphasized through a significant improvement of the spatial distribution of the Ge nanoparticles and by avoiding multi-step fabrication processes or Ge loss. The influence of the preparation conditions on structural, electrical and optical properties of the fabricated nanostructures was studied by X-ray diffraction, transmission electron microscopy, electrical measurements in dark or under illumination and response time investigations. Finally, we demonstrate the feasibility of the procedure by the means of an Al/n-Si/Ge:SiO2/ITO photodetector test structure. The structures, investigated at room temperature, show superior performance, high photoresponse gain, high responsivity (about 7 AW−1, fast response time (0.5 µs at 4 kHz and great optoelectronic conversion efficiency of 900% in a wide operation bandwidth, from 450 to 1300 nm. The obtained photoresponse gain and the spectral width are attributed mainly to the high Ge content packed into a SiO2 matrix showing the direct connection between synthesis and optical properties of the tested nanostructures. Our deposition approach put in evidence the great potential of Ge nanoparticles embedded in a SiO2 matrix for hybrid integration, as they may be employed in structures and devices individually or with other materials, hence the possibility of fabricating various heterojunctions on Si, glass or flexible substrates for future development of Si

  1. Soy protein polymers: Enhancing the water stability property

    Science.gov (United States)

    Srinivasan, Gowrishankar

    Soy protein based plastics have been processed in the past by researchers for various short-term applications; however a common issue is the high water sensitivity of these plastics. This work concentrates on resolving this water sensitivity issue of soy protein polymers by employing chemical and mechanical interaction at the molecular level during extrusion. The primary chemical interactions employed were anhydride chemistries such as maleic anhydride (MA), phthalic anhydride (PTA), and butylated hydroxyanisole (BHA). These were respectively used in conjunction with glycerol as a plasticizer to produce relatively water stable soy protein based plastics. Formulations with varying additive levels of the chemistries were extruded and injection molded to form the samples for characterization. The additive levels of anhydrides were varied between 3-10% tw/tw (total mass). Results indicated that phthalic anhydride formulations resulted in highest water stability. Plastic formulations with concentration up to 10% phthalic anhydride were observed to have water absorption as low as 21.5% after 24 hrs of exposure to water with respect to 250% for the control formulation. Fourier transform infrared spectroscopy (FTIR) was utilized to characterize and confirm the fundamental mechanisms of water stability achieved by phthalic and maleic anhydride chemistries. In addition, the anhydride formulations were modified by inclusion of cotton fibers and pretreated cotton powder in order to improve mechanical properties. The incorporation of cotton fibers improved the dry strength by 18%, but did not significantly improve the wet state strength of the plastics. It was also observed that the butylated-hydroxy anisole (BHA) formulation exhibited high extension values in the dry state and had inferior water absorption properties in comparison with anhydride formulations.

  2. Enhancement of Ultrahigh Performance Concrete Material Properties with Carbon Nanofiber

    Directory of Open Access Journals (Sweden)

    Libya Ahmed Sbia

    2014-01-01

    Full Text Available Ultrahigh performance concrete (UHPC realized distinctly high mechanical, impermeability, and durability characteristics by reducing the size and content of capillary pore, refining the microstructure of cement hydrates, and effectively using fiber reinforcement. The dense and fine microstructure of UHPC favor its potential to effectively disperse and interact with nanomaterials, which could complement the reinforcing action of fibers in UHPC. An optimization experimental program was implemented in order to identify the optimum combination of steel fiber and relatively low-cost carbon nanofiber in UHPC. The optimum volume fractions of steel fiber and carbon nanofiber identified for balanced improvement of flexural strength, ductility, energy sorption capacity, impact, and abrasion resistance of UHPC were 1.1% and 0.04%, respectively. Desired complementary/synergistic actions of nanofibers and steel fibers in UHPC were detected, which were attributed to their reinforcing effects at different scales, and the potential benefits of nanofibers to interfacial bonding and pull-out behavior of fibers in UHPC. Modification techniques which enhanced the hydrophilicity and bonding potential of nanofibers to cement hydrates benefited their reinforcement efficiency in UHPC.

  3. Carbon Nanotube Chopped Fiber for Enhanced Properties in Additive Manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Menchhofer, Paul A [ORNL; Lindahl, John M [ORNL; JohnsonPhD, DR Joseph E. [Nanocomp Technologies, Inc.

    2016-06-06

    Nanocomp Technologies, Inc. is working with Oak Ridge National Laboratory to develop carbon nanotube (CNT) composite materials and evaluate their use in additive manufacturing (3D printing). The first phase demonstrated feasibility and improvements for carbon nanotube (CNT)- acrylonitrile butadiene styrene (ABS) composite filaments use in additive manufacturing, with potential future work centering on further improvements. By focusing the initial phase on standard processing methods (developed mainly for the incorporation of carbon fibers in ABS) and characterization techniques, a basis of knowledge for the incorporation of CNTs in ABS was learned. The ability to understand the various processing variables is critical to the successful development of these composites. From the degradation effects on ABS (caused by excessive temperatures), to the length of time the ABS is in the melt state, to the order of addition of constituents, and also to the many possible mixing approaches, a workable flow sequence that addresses each processing step is critical to the final material properties. Although this initial phase could not deal with each of these variables in-depth, a future study is recommended that will build on the lessons learned for this effort.

  4. Modifying zirconia solid electrolyte surface property to enhance oxide transport

    Energy Technology Data Exchange (ETDEWEB)

    Liaw, B.Y.; Song, S.Y. [Univ. of Hawaii, Honolulu, HI (United States)

    1996-12-31

    Bismuth-strontium-calcium-copper oxide (Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8}, BSCCO) is known for its high T{sub c} superconducting behavior and mixed conducting property. The applicability of similar high T{sub c} cuprates for intermediate-temperature solid oxide fuel cell (SOFC) application has been studied recently. We investigated the electrochemical behavior of several Ag{vert_bar}BSCCO{vert_bar}10 mol% yttria-stabilized zirconia (YSZ){vert_bar}Ag and Ag{vert_bar}YSZ{vert_bar}Ag cells using complex impedance spectroscopy. A highly uniform and porous microstructure was observed at the interface of the YSZ and BSCCO. The ionic conductivity determined from the Nyquest plots in the temperature range of 200-700{degrees}C agrees with the values reported in the literature. The specific resistance of the BSCCO{vert_bar}YSZ interface was also determined to be lower than those of the conventional manganite electrode, suggesting that BSCCO seems attractive for cathode applications in SOFC.

  5. Chemical Potential Tuning and Enhancement of Thermoelectric Properties in Indium Selenides

    Directory of Open Access Journals (Sweden)

    Jong-Soo Rhyee

    2015-03-01

    Full Text Available Researchers have long been searching for the materials to enhance thermoelectric performance in terms of nano scale approach in order to realize phonon-glass-electron-crystal and quantum confinement effects. Peierls distortion can be a pathway to enhance thermoelectric figure-of-merit ZT by employing natural nano-wire-like electronic and thermal transport. The phonon-softening known as Kohn anomaly, and Peierls lattice distortion decrease phonon energy and increase phonon scattering, respectively, and, as a result, they lower thermal conductivity. The quasi-one-dimensional electrical transport from anisotropic band structure ensures high Seebeck coefficient in Indium Selenide. The routes for high ZT materials development of In4Se3−δ are discussed from quasi-one-dimensional property and electronic band structure calculation to materials synthesis, crystal growth, and their thermoelectric properties investigations. The thermoelectric properties of In4Se3−δ can be enhanced by electron doping, as suggested from the Boltzmann transport calculation. Regarding the enhancement of chemical potential, the chlorine doped In4Se3−δCl0.03 compound exhibits high ZT over a wide temperature range and shows state-of-the-art thermoelectric performance of ZT = 1.53 at 450 °C as an n-type material. It was proven that multiple elements doping can enhance chemical potential further. Here, we discuss the recent progress on the enhancement of thermoelectric properties in Indium Selenides by increasing chemical potential.

  6. Clinical pharmacology of labetalol

    Science.gov (United States)

    Richards, D. A.; Prichard, B. N. C.

    1979-01-01

    1 The clinical pharmacology of labetalol has been evaluated using pharmacological and physiological test methods. 2 Labetalol displaces the log dose-response curves to the right of isoprenaline-induced increases in heart rate, cardiac output and decreases in diastolic BP. The similarity in the displacements of these curves suggests labetalol has non-selective β-adrenoceptor-blocking properties. 3 Labetalol inhibits exercise-induced increases in heart rate and systolic BP, inhibits tilt tachycardia and that associated with Valsalva's manoeuvre. 4 Direct comparison with propranolol using the methods above have shown that the β-adrenoceptor-blocking effect of labetalol is qualitatively similar to that of propranolol but that propranolol is more potent weight for weight to the order of 4 to 6:1 propranolol:labetalol. In respect of their effects on respiratory function, labetalol and propranolol are qualitatively different; whereas propranolol increases airways resistance in equipotent β-adrenoceptor-blocking doses, labetalol does not. 5 Labetalol displaces the log dose-response curves of phenylephrine and noradrenaline-induced increases in systolic and diastolic BPs to the right consistent with an α-adrenoceptor-blocking action. 6 Labetalol inhibits increases in BP due to a cold stimulus, whereas propranolol does not. 7 The combined α- and β-adrenoceptor-blocking effect of labetalol after acute and chronic administration leads to reductions in BP and peripheral resistance but little change in heart rate or cardiac output at rest. During exercise, increases in BP and heart rate are attenuated but cardiac output increases are only significantly diminished at high levels of exercise. 8 Labetalol is less lipophylic than propranolol, with a partition coefficient of 1.2. It is almost completely metabolized being extensively conjugated. PMID:43165

  7. Pharmacological effects of Sapindus mukorossi

    OpenAIRE

    Upadhyay,Aparna; Singh,D.K.

    2012-01-01

    Sapindus mukorossi is an extremely valuable medicinal plant, distributed in tropical and sub-tropical regions of Asia. The aim of present review is to form a short compilation of the phytochemical composition and pharmacological properties of this multipurpose tree. The main phytoconstituents isolated and identified from different parts of this plant are triterpenoidal saponins of oleanane, dammarane and tirucullane type. The structure and chemical names of all the types of triterpenoidal sap...

  8. Enhanced mechanical and thermal properties of regenerated cellulose/graphene composite fibers.

    Science.gov (United States)

    Tian, Mingwei; Qu, Lijun; Zhang, Xiansheng; Zhang, Kun; Zhu, Shifeng; Guo, Xiaoqing; Han, Guangting; Tang, Xiaoning; Sun, Yaning

    2014-10-13

    In this study, a wet spinning method was applied to fabricate regenerated cellulose fibers filled with low graphene loading which was systematically characterized by SEM, TEM, FTIR and XRD techniques. Subsequently, the mechanical and thermal properties of the resulting fibers were investigated. With only 0.2 wt% loading of graphene, a ∼ 50% improvement of tensile strength and 25% enhancement of Young's modulus were obtained and the modified Halpin-Tsai model was built to predict the mechanical properties of composite fibers. Thermal analysis of the composite fibers showed remarkably enhanced thermal stability and dynamic heat transfer performance of graphene-filled cellulose composite fiber, also, the presence of graphene oxide can significantly enhance the thermal conductivity of the composite fiber. This work provided a facile way to improve mechanical and thermal properties of regenerated cellulose fibers. The resultant composite fibers have potential application in thermal insulation and reinforced fibrous materials. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. O-(carboxymethyl)-chitosan nanofiltration membrane surface functionalized with graphene oxide nanosheets for enhanced desalting properties.

    Science.gov (United States)

    Wang, Jiali; Gao, Xueli; Wang, Jian; Wei, Yi; Li, Zhaokui; Gao, Congjie

    2015-02-25

    A novel O-(carboxymethyl)-chitosan (OCMC) nanofiltration (NF) membrane is developed via surface functionalization with graphene oxide (GO) nanosheets to enhance desalting properties. Using ring-opening polymerization between epoxy groups of GO nanosheets and amino groups of OCMC active layer, GO nanosheets are irreversibly bound to the membrane. The OCMC NF membranes surface-functionalized with GO nanosheets are characterized by Fourier-transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, atomic force microscopy, contact angle analyzer, and zeta potential analyzer. The membranes exhibit not only higher permeability but also better salt rejections than the pristine membranes and the commercial NF membranes; besides, the desalting properties are enhanced with the concentration of GO nanosheets increasing. Furthermore, the transport mechanism of GO-OCMC NF membranes reveals that the nanoporous structure of GO-OCMC functional layer and size exclusion and electrostatic repulsion of water nanochannels formed by GO nanosheets lead to the membranes possessing enhanced desalting properties.

  10. Chemistry, Pharmacology, and Medicinal Property of Sage (Salvia to Prevent and Cure Illnesses such as Obesity, Diabetes, Depression, Dementia, Lupus, Autism, Heart Disease, and Cancer

    Directory of Open Access Journals (Sweden)

    Mohsen Hamidpour

    2014-04-01

    Full Text Available For a long time, sage (Salvia species have been used in traditional medicine for the relief of pain, protecting the body against oxidative stress, free radical damages, angiogenesis, inflammation, bacterial and virus infection, etc., Several studies suggest that sage species can be considered for drug development because of their reported pharmacology and therapeutic activities in many countries of Asia and Middle East, especially China and India. These studies suggest that Salvia species, in addition to treating minor common illnesses, might potentially provide novel natural treatments for the relief or cure of many serious and life-threatening diseases such as depression, dementia, obesity, diabetes, lupus, heart disease, and cancer. This article presents a comprehensive analysis of the botanical, chemical, and pharmacological aspects of sage (Saliva.

  11. Chemistry, Pharmacology, and Medicinal Property of Sage (Salvia) to Prevent and Cure Illnesses such as Obesity, Diabetes, Depression, Dementia, Lupus, Autism, Heart Disease, and Cancer.

    Science.gov (United States)

    Hamidpour, Mohsen; Hamidpour, Rafie; Hamidpour, Soheila; Shahlari, Mina

    2014-04-01

    For a long time, sage (Salvia) species have been used in traditional medicine for the relief of pain, protecting the body against oxidative stress, free radical damages, angiogenesis, inflammation, bacterial and virus infection, etc., Several studies suggest that sage species can be considered for drug development because of their reported pharmacology and therapeutic activities in many countries of Asia and Middle East, especially China and India. These studies suggest that Salvia species, in addition to treating minor common illnesses, might potentially provide novel natural treatments for the relief or cure of many serious and life-threatening diseases such as depression, dementia, obesity, diabetes, lupus, heart disease, and cancer. This article presents a comprehensive analysis of the botanical, chemical, and pharmacological aspects of sage (Saliva).

  12. Ayahuasca: Pharmacology, neuroscience and therapeutic potential.

    Science.gov (United States)

    Domínguez-Clavé, Elisabet; Soler, Joaquim; Elices, Matilde; Pascual, Juan C; Álvarez, Enrique; de la Fuente Revenga, Mario; Friedlander, Pablo; Feilding, Amanda; Riba, Jordi

    2016-09-01

    Ayahuasca is the Quechua name for a tea obtained from the vine Banisteriopsis caapi, and used for ritual purposes by the indigenous populations of the Amazon. The use of a variation of the tea that combines B. caapi with the leaves of the shrub Psychotria viridis has experienced unprecedented expansion worldwide for its psychotropic properties. This preparation contains the psychedelic 5-HT 2A receptor agonist N,N-dimethyltryptamine (DMT) from P. viridis, plus β-carboline alkaloids with monoamine-oxidase-inhibiting properties from B. caapi. Acute administration induces a transient modified state of consciousness characterized by introspection, visions, enhanced emotions and recollection of personal memories. A growing body of evidence suggests that ayahuasca may be useful to treat substance use disorders, anxiety and depression. Here we review the pharmacology and neuroscience of ayahuasca, and the potential psychological mechanisms underlying its therapeutic potential. We discuss recent findings indicating that ayahuasca intake increases certain mindfulness facets related to acceptance and to the ability to take a detached view of one's own thoughts and emotions. Based on the available evidence, we conclude that ayahuasca shows promise as a therapeutic tool by enhancing self-acceptance and allowing safe exposure to emotional events. We postulate that ayahuasca could be of use in the treatment of impulse-related, personality and substance use disorders and also in the handling of trauma. More research is needed to assess the full potential of ayahuasca in the treatment of these disorders. Copyright © 2016 Elsevier Inc. All rights reserved.

  13. [Properties of gas (CO2) microbubbles made by hand agitation and it's contrast enhancing effect].

    Science.gov (United States)

    Matsuda, Y; Yabuuchi, I; Ito, T

    1998-04-01

    The property of gas (CO2) microbubbles made by hand agitation and it's contrast enhancing effect of abdominal organs on gray scale ultrasound are here described. The size of microbubbles of CO2 gas adequately prepared with 5% human serum albumin was nearly 23 microns in mean diameter. However, the size and the density of gas microbubbles are affected with many factors, including mixing times, volume ratio of gas and liquid and the species of gas and liquid. On the other hand, contrast enhancing effect is determined by the size and the density of gas microbubbles. For the adequate evaluation of contrast enhancing effect of abdominal tumors by enhanced ultrasonography, the property of gas microbubbles described as above should be carefully considered.

  14. Antioxidant property enhancement of sweet potato flour under simulated gastrointestinal pH.

    Science.gov (United States)

    Chan, Kim Wei; Khong, Nicholas M H; Iqbal, Shahid; Umar, Imam Mustapha; Ismail, Maznah

    2012-01-01

    Sweet potato is known to be rich in healthful antioxidants, but the stability of its antioxidant properties under gastrointestinal pH is very much unknown. Hence, this study aimed to evaluate the changes in antioxidant properties (total contents of phenolics and flavonoids as well as antioxidant activity) of sweet potato flour (SPF) under simulated gastrointestinal pH conditions. It was found that the yield of SPF crude phenolic extract increased from 0.29 to 3.22 g/100 g SPF upon subjection to gastrointestinal pH conditions (p antioxidant activity of SPF (p antioxidant properties of SPF were enhanced under gastrointestinal pH conditions, suggesting that SPF might possess a considerable amount of bound phenolic and other antioxidative compounds. The antioxidant properties of SPF are largely influenced by pH and thus might be enhanced during the in vivo digestive process.

  15. Studies in neuroendocrine pharmacology

    Science.gov (United States)

    Maickel, R. P.

    1976-01-01

    The expertise and facilities available within the Medical Sciences Program section on Pharmacology were used along with informational input from various NASA sources to study areas relevant to the manned space effort. Topics discussed include effects of drugs on deprivation-induced fluid consumption, brain biogenic amines, biochemical responses to stressful stimuli, biochemical and behavioral pharmacology of amphetamines, biochemical and pharmacological studies of analogues to biologically active indole compounds, chemical pharmacology: drug metabolism and disposition, toxicology, and chemical methodology. Appendices include a bibliography, and papers submitted for publication or already published.

  16. Molecular design of seed storage proteins for enhanced food physicochemical properties.

    Science.gov (United States)

    Tandang-Silvas, Mary Rose G; Tecson-Mendoza, Evelyn Mae; Mikami, Bunzo; Utsumi, Shigeru; Maruyama, Nobuyuki

    2011-01-01

    Seed storage proteins such as soybean globulins have been nutritionally and functionally valuable in the food industry. Protein structure-function studies are valuable in modifying proteins for enhanced functionality. Recombinant technology and protein engineering are two of the tools in biotechnology that have been used in producing soybean proteins with better gelling property, solubility, and emulsifying ability. This article reviews the molecular basis for the logical and precise protein designs that are important in obtaining the desired improved physicochemical properties.

  17. Electrospun Polymeric Scaffolds with Enhanced Biomimetic Properties for Tissue Engineering Applications

    OpenAIRE

    Fiorani, Andrea

    2014-01-01

    This PhD Thesis is focused on the development of fibrous polymeric scaffolds for tissue engineering applications and on the improvement of scaffold biomimetic properties. Scaffolds were fabricated by electrospinning, which allows to obtain scaffolds made of polymeric micro or nanofibers. Biomimetism was enhanced by following two approaches: (1) the use of natural biopolymers, and (2) the modification of the fibers surface chemistry. Gelatin was chosen for its bioactive properties and cellu...

  18. Pharmacological effects of lavandulifolioside from Leonurus cardiaca.

    Science.gov (United States)

    Miłkowska-Leyck, Katarzyna; Filipek, Barbara; Strzelecka, Halina

    2002-04-01

    Lavandulifolioside was detected for the first time in Leonurus cardiaca var. vulgaris [Moench] Briquet (Lamiaceae). The isolation was performed from the butanolic extract of the aerial parts and the identification by NMR and MS. The pharmacological properties of lavandulifolioside consist of significant negative chronotropism, prolongation of the P-Q, Q-T intervals and QRS complex, and decrease of blood pressure. Contrary to the butanolic extract lavandulifolioside did not reduce the spontaneous locomotor activity. In conclusion, the pharmacological pattern of lavandulifolioside did not explain the pharmacological effects of L. cardiaca L. alone.

  19. Molecular pharmacology of human NMDA receptors

    DEFF Research Database (Denmark)

    Hedegaard, Maiken; Hansen, Kasper Bø; Andersen, Karen Toftegaard

    2012-01-01

    current knowledge of the relationship between NMDA receptor structure and function. We summarize studies on the biophysical properties of human NMDA receptors and compare these properties to those of rat orthologs. Finally, we provide a comprehensive pharmacological characterization that allows side......-by-side comparison of agonists, un-competitive antagonists, GluN2B-selective non-competitive antagonists, and GluN2C/D-selective modulators at recombinant human and rat NMDA receptors. The evaluation of biophysical properties and pharmacological probes acting at different sites on the receptor suggest...... that the binding sites and conformational changes leading to channel gating in response to agonist binding are highly conserved between human and rat NMDA receptors. In summary, the results of this study suggest that no major detectable differences exist in the pharmacological and functional properties of human...

  20. Fundamentals of Experimental Pharmacology

    National Research Council Canada - National Science Library

    Bhatt, J

    2012-01-01

    ... or in human volunteers. Thus, an experimental pharmacology using animal models continues to be the starting point for a new drug research. The book Fundamentals of Experimental Pharmacology by Dr. M. N. Ghosh has really been a cornerstone for postgraduate students and researchers engaged in animal experimentation. It has always been useful for pos...

  1. Fundamentals of Experimental Pharmacology

    National Research Council Canada - National Science Library

    Ghosh, M

    2007-01-01

    ... to its unique approach in comparison to other books available on Experimental pharmacology. The main purpose of this book was to give a theoretical background followed by the appropriate experimental techniques. The late Prof. H. O. Schild, then Professor of Pharmacology, University College London in his brief introduction to the first editi...

  2. Pharmacology Information System Ready

    Science.gov (United States)

    Chemical and Engineering News, 1973

    1973-01-01

    Discusses the development and future of Prophet,'' a specialized information handling system for pharmacology research. It is designed to facilitate the acquisition and dissemination of knowledge about mechanisms of drug action, and it is hoped that it will aid in converting pharmacology research from an empirical to a predictive science. (JR)

  3. SnO2 nanosheets grown on graphene sheets with enhanced lithium storage properties.

    Science.gov (United States)

    Ding, Shujiang; Luan, Deyan; Boey, Freddy Yin Chiang; Chen, Jun Song; Lou, Xiong Wen David

    2011-07-07

    We demonstrate a new hydrothermal method to directly grow SnO(2) nanosheets on a graphene oxide support that is subsequently reduced to graphene. This unique SnO(2)/graphene hybrid structure exhibits enhanced lithium storage properties with high reversible capacities and good cycling performance. This journal is © The Royal Society of Chemistry 2011

  4. Pharmacological effects of Sapindus mukorossi.

    Science.gov (United States)

    Upadhyay, Aparna; Singh, D K

    2012-01-01

    Sapindus mukorossi is an extremely valuable medicinal plant, distributed in tropical and sub-tropical regions of Asia. The aim of present review is to form a short compilation of the phytochemical composition and pharmacological properties of this multipurpose tree. The main phytoconstituents isolated and identified from different parts of this plant are triterpenoidal saponins of oleanane, dammarane and tirucullane type. The structure and chemical names of all the types of triterpenoidal saponins reported in Sapindus mukorossi are included in this review. Many research studies have been conducted to prove the plant's potential as being spermicidal, contraceptive, hepatoprotective, emetic, anti-inflammatory and anti-protozoal. The present review highlights some of the salient pharmacological uses of Sapindus mukorossi.

  5. Pharmacological effects of Sapindus mukorossi

    Directory of Open Access Journals (Sweden)

    Aparna Upadhyay

    2012-10-01

    Full Text Available Sapindus mukorossi is an extremely valuable medicinal plant, distributed in tropical and sub-tropical regions of Asia. The aim of present review is to form a short compilation of the phytochemical composition and pharmacological properties of this multipurpose tree. The main phytoconstituents isolated and identified from different parts of this plant are triterpenoidal saponins of oleanane, dammarane and tirucullane type. The structure and chemical names of all the types of triterpenoidal saponins reported in Sapindus mukorossi are included in this review. Many research studies have been conducted to prove the plant's potential as being spermicidal, contraceptive, hepatoprotective, emetic, anti-inflammatory and anti-protozoal. The present review highlights some of the salient pharmacological uses of Sapindus mukorossi.

  6. Pharmacology of cannabinoids.

    Science.gov (United States)

    Grotenhermen, Franjo

    2004-01-01

    Dronabinol (Delta 9-tetrahydocannabinol, THC), the main source of the pharmacological effects caused by the use of cannabis, is an agonist to both the CB1 and the CB2 subtype of cannabinoid receptors. It is available on prescription in several countries. The non-psychotropic cannabidiol (CBD), some analogues of natural cannabinoids and their metabolites, antagonists at the cannabinoid receptors and modulators of the endogenous cannabinoid system are also promising candidates for clinical research and therapeutic uses. Cannabinoid receptors are distributed in the central nervous system and many peripheral tissues including spleen, leukocytes; reproductive, urinary and gastrointestinal tracts; endocrine glands, arteries and heart. Five endogenous cannabinoids have been detected so far, of whom anandamide and 2-arachidonylglycerol are best characterized. There is evidence that besides the two cannabinoid receptor subtypes cloned so far additional cannabinoid receptor subtypes and vanilloid receptors are involved in the complex physiological functions of the cannabinoid system that include motor coordination, memory procession, control of appetite, pain modulation and neuroprotection. Strategies to modulate their activity include inhibition of re-uptake into cells and inhibition of their degradation to increase concentration and duration of action. Properties of cannabinoids that might be of therapeutic use include analgesia, muscle relaxation, immunosuppression, anti-inflammation, anti-allergic effects, sedation, improvement of mood, stimulation of appetite, anti-emesis, lowering of intraocular pressure, bronchodilation, neuroprotection and antineoplastic effects.

  7. Preparation and enhanced mechanical properties of hybrid hydrogels comprising ultralong hydroxyapatite nanowires and sodium alginate.

    Science.gov (United States)

    Jiang, Ying-Ying; Zhu, Ying-Jie; Li, Heng; Zhang, Yong-Gang; Shen, Yue-Qin; Sun, Tuan-Wei; Chen, Feng

    2017-07-01

    Hydrogels with 3-dimentional cross-linked structures are widely used in various biomedical fields such as bone repair scaffolds, drug carriers and biosensors. However, the applications of hydrogels are usually restricted because of their poor mechanical properties. Currently, nanocomposites, double network systems, hydrophobic association, macromolecules, and nanoparticles are commonly adopted as cross-linking agents to enhance mechanical properties of hydrogels. In this work, ultralong hydroxyapatite nanowires (HANWs) with lengths of several hundred microns are prepared and used to enhance the mechanical properties of sodium alginate (SA)-based hydrogels. Using divalent calcium ions as the cross-linking agent, the hybrid HANWs/SA hydrogels containing various percentages of HANWs are obtained. The as-prepared HANWs/SA hybrid hydrogels have a porous structure with pore sizes ranging from about 200 to 500μm. The mechanical properties of SA hydrogels can be significantly improved by incorporating HANWs. The maximum compressive modulus (E50%) and tensile Young's modulus of the hybrid hydrogel (HANWs/SA=2:1) are as high as 0.123MPa and 0.994MPa, which are about 162% and 614% those of the pure SA hydrogel, respectively. Due to the enhanced mechanical properties and high biocompatibility, the as-prepared HANWs/SA hybrid hydrogels have promising applications in various biomedical fields such as bone defect repair. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Superior Long-Term Synaptic Memory Induced by Combining Dual Pharmacological Activation of PKA and ERK with an Enhanced Training Protocol

    Science.gov (United States)

    Liu, Rong-Yu; Neveu, Curtis; Smolen, Paul; Cleary, Leonard J.; Byrne, John H.

    2017-01-01

    Developing treatment strategies to enhance memory is an important goal of neuroscience research. Activation of multiple biochemical signaling cascades, such as the protein kinase A (PKA) and extracellular signal-regulated kinase (ERK) pathways, is necessary to induce long-term synaptic facilitation (LTF), a correlate of long-term memory (LTM).…

  9. Enhanced catalytic properties of mesoporous mordenite for benzylation of benzene with benzyl alcohol

    Energy Technology Data Exchange (ETDEWEB)

    Saxena, Sandeep K.; Viswanadham, Nagabhatla, E-mail: nagabhatla.viswanadham@gmail.com

    2017-01-15

    Graphical abstract: The nano size pores (∼10 nm) created in the microporous mordenite zeolite facilitated enhanced catalytic activity to produce as high as 97 wt.% yield of di-phenyl methane in the benzylation of benzene with benzyl alcohol at solvent-free liquid phase reaction conditions. - Highlights: • Nano pores of ∼10 nm size have been created in microporous mordenite. • Dealumination at optimized conditions resulted in enhanced properties of mordenite. • Hierarchically porous mordenite enhanced bulky catalytic reactions. • As high as 97% selectivity to Di-phenyl methane obtained. • Solvent-free, liquid phase alkylation catalyst with stable activity for reusability. - Abstract: Zeolite mordenite has been treated with nitric acid at different severities so as to facilitate the framework dealumination and optimization of the textural properties such as acidity and porosity. The samples obtained have been characterized by X-ray diffraction, FTIR, SEM, TEM, surface area, porosity by N{sub 2} adsorption and ammonia TPD. The resultant samples have been evaluated towards the bulky alkylation reaction of benzylation of benzene with benzyl alcohol. The studies indicated the improvement in the textural properties such as surface area, pore volume and acidity of the samples after the acid treatment. While, the phenomenon of enhancement in properties was exhibited by all the acid treated mordenite samples, the highest improvement in properties was observed at a particular condition of acid treatment (SM-2 sample). This particular sample also exhibited highest acidity and the presence of ∼10 nm size pores that resulted in the effective catalytic activity towards the bulky alkylation reaction of benzene with benzyl alcohol to produce high yields of di-phenyl methane.

  10. Advancing pharmacometrics and systems pharmacology.

    Science.gov (United States)

    Waldman, S A; Terzic, A

    2012-11-01

    Pharmacometrics and systems pharmacology are emerging as principal quantitative sciences within drug development and experimental therapeutics. In recognition of the importance of pharmacometrics and systems pharmacology to the discipline of clinical pharmacology, the American Society for Clinical Pharmacology and Therapeutics (ASCPT), in collaboration with Nature Publishing Group and Clinical Pharmacology & Therapeutics, has established CPT: Pharmacometrics & Systems Pharmacology to inform the field and shape the discipline.

  11. Advancing Pharmacometrics and Systems Pharmacology

    Science.gov (United States)

    Waldman, SA; Terzic, A

    2017-01-01

    Pharmacometrics and systems pharmacology are emerging as principal quantitative sciences within drug development and experimental therapeutics. In recognition of the importance of pharmacometrics and systems pharmacology to the discipline of clinical pharmacology, the American Society for Clinical Pharmacology and Therapeutics (ASCPT), in collaboration with Nature Publishing Group and Clinical Pharmacology & Therapeutics, has established CPT: Pharmacometrics & Systems Pharmacology to inform the field and shape the discipline. PMID:23085873

  12. Enhancement of heat transfer coefficient multi-metallic nanofluid with ANFIS modeling for thermophysical properties

    Directory of Open Access Journals (Sweden)

    Balla Hyder H.

    2015-01-01

    Full Text Available Cu and Zn-water nanofluid is a suspension of the Cu and Zn nanoparticles with the size 50 nm in the water base fluid for different volume fractions to enhance its Thermophysical properties. The determination and measuring the enhancement of Thermophysical properties depends on many limitations. Nanoparticles were suspended in a base fluid to prepare a nanofluid. A coated transient hot wire apparatus was calibrated after the building of the all systems. The vibro-viscometer was used to measure the dynamic viscosity. The measured dynamic viscosity and thermal conductivity with all parameters affected on the measurements such as base fluids thermal conductivity, volume factions, and the temperatures of the base fluid were used as input to the Artificial Neural Fuzzy inference system to modeling both dynamic viscosity and thermal conductivity of the nanofluids. Then, the ANFIS modeling equations were used to calculate the enhancement in heat transfer coefficient using CFD software. The heat transfer coefficient was determined for flowing flow in a circular pipe at constant heat flux. It was found that the thermal conductivity of the nanofluid was highly affected by the volume fraction of nanoparticles. A comparison of the thermal conductivity ratio for different volume fractions was undertaken. The heat transfer coefficient of nanofluid was found to be higher than its base fluid. Comparisons of convective heat transfer coefficients for Cu and Zn nanofluids with the other correlation for the nanofluids heat transfer enhancement are presented. Moreover, the flow demonstrates anomalous enhancement in heat transfer nanofluids.

  13. Plasmon mediated enhancement and tuning of optical emission properties of two dimensional graphitic carbon nitride nanosheets

    Science.gov (United States)

    Bayan, Sayan; Gogurla, Narendar; Midya, Anupam; Singha, Achintya; Ray, Samit K.

    2017-12-01

    We demonstrate surface plasmon induced enhancement and tunablilty in optical emission properties of two dimensional graphitic carbon nitride (g-C3N4) nanosheets through the attachment of gold (Au) nanoparticles. Raman spectroscopy has revealed surface enhanced Raman scattering that arises due to the combined effect of the charge transfer process and localized surface plasmon induced enhancement in electromagnetic field, both occurring at the nanoparticle–nanosheet interface. Photoluminescence studies suggest that at an optimal concentration of nanoparticles, the emission intensity can be enhanced, which is maximum within the 500–525 nm region. Further, the fabricated electroluminescent devices reveal that the emission feature can be tuned from bluish-green to red (∼160 nm shift) upon attaching Au nanoparticles. We propose that the π*→π transition in g-C3N4 can trigger surface plasmon oscillation in Au, which subsequently increases the excitation process in the nanosheets and results in enhanced emission in the green region of the photoluminescence spectrum. On the other hand, electroluminescence of g-C3N4 can induce plasmon oscillation more efficiently and thus can lead to red emission from Au nanoparticles through the radiative damping of particle plasmons. The influence of nanoparticle size and coverage on the emission properties of two dimensional g-C3N4, nanosheets has also been studied in detail.

  14. Structure-Based Small Molecule Modulation of a Pre-Amyloid State: Pharmacological Enhancement of IAPP Membrane-Binding and Toxicity

    Science.gov (United States)

    Nath, Abhinav; Schlamadinger, Diana E.; Rhoades, Elizabeth; Miranker, Andrew D.

    2015-01-01

    Islet amyloid polypeptide (IAPP) is a peptide hormone whose pathological self-assembly is a hallmark of the progression of type II diabetes. IAPP–membrane interactions catalyze its higher-order self-assembly and also underlie its toxic effects toward cells. While there is great interest in developing small molecule reagents capable of altering the structure and behavior of oligomeric, membrane-bound IAPP, the dynamic and heterogeneous nature of this ensemble makes it recalcitrant to traditional approaches. Here, we build on recent insights into the nature of membrane-bound states and develop a combined computational and experimental strategy to address this problem. The generalized structural approach efficiently identified diverse compounds from large commercial libraries with previously unrecognized activities toward the gain-of-function behaviors of IAPP. The use of appropriate computational prescreening reduced the experimental burden by orders of magnitude relative to unbiased high-throughput screening. We found that rationally targeting experimentally derived models of membrane-bound dimers identified several compounds that demonstrate the remarkable ability to enhance IAPP–membrane binding and one compound that enhances IAPP-mediated cytotoxicity. Taken together, these findings imply that membrane binding per se is insufficient to generate cytotoxicity; instead, enhanced sampling of rare states within the membrane-bound ensemble may potentiate IAPP’s toxic effects. PMID:25966003

  15. Enhanced microwave absorbing properties and heat resistance of carbonyl iron by electroless plating Co

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hongyu, E-mail: wanghongyu07010310@163.com; Zhu, Dongmei; Zhou, Wancheng; Luo, Fa

    2015-11-01

    Co coated carbonyl iron particles (Co (CI)) are fabricated through electroless plating method, and the electromagnetic microwave absorbing properties are investigated in the frequencies during 8.2–12.4 GHz. The complex permittivity of CI particles after electroless plating Co is higher than that of raw CI particles due to improvment of the polarization process. Furthermore, according to the XRD and TG results, the Co layer can enhance the heat resistance of CI particles. The bandwidth below −10 dB can reach 3.9 GHz for the Co(CI) absorbent. The results indicate that the electroless plating Co not only enhances the absorbing properties but also improves the heat resistance of CI. - Highlights: • The Co-coated carbonyl iron Co(CI) particles were prepared by electroless plating. • The electromagnetic wave absorbing properties of Co(CI) particles were studied. • The heat treatment on the absorbing property of Co(CI) particles was studied. • The Co(CI) particles have good absorbing property when compared with CI.

  16. Clinical pharmacology of caffeine.

    Science.gov (United States)

    Benowitz, N L

    1990-01-01

    Caffeine is the most widely consumed stimulant drug in the world. This chapter reviews the human pharmacology of caffeine; the evidence for its role in causing human disease, including addiction; and its potential usefulness as a therapeutic agent.

  17. Non-toxic poly(ethylene terephthalate)/clay nanocomposites with enhanced barrier properties

    KAUST Repository

    Hayrapetyan, Suren

    2012-01-01

    Motivated by the technological need for poly(ethylene terephthalate) materials with improved barrier properties together with the requirement for sustainability this study focuses on an eco-friendly sulfonated polyester as clay compatibilizer to facilitate polymer mixing during melt compounding. We demonstrate that the nanocomposites based on sulfonated polyester are a reliable alternative to their imidazolium counterparts, exhibiting enhanced properties (water vapor and UV transmission), without sacrificing the excellent transparency, clarity and mechanical strength of the matrix. © 2011 Elsevier Ltd. All rights reserved.

  18. The pharmacology of psilocybin.

    Science.gov (United States)

    Passie, Torsten; Seifert, Juergen; Schneider, Udo; Emrich, Hinderk M

    2002-10-01

    Psilocybin (4-phosphoryloxy-N,N-dimethyltryptamine) is the major psychoactive alkaloid of some species of mushrooms distributed worldwide. These mushrooms represent a growing problem regarding hallucinogenic drug abuse. Despite its experimental medical use in the 1960s, only very few pharmacological data about psilocybin were known until recently. Because of its still growing capacity for abuse and the widely dispersed data this review presents all the available pharmacological data about psilocybin.

  19. Enhanced performance in capacitive force sensors using carbon nanotube/polydimethylsiloxane nanocomposites with high dielectric properties

    Science.gov (United States)

    Jang, Hyeyoung; Yoon, Hyungsuk; Ko, Youngpyo; Choi, Jaeyoo; Lee, Sang-Soo; Jeon, Insu; Kim, Jong-Ho; Kim, Heesuk

    2016-03-01

    Force sensors have attracted tremendous attention owing to their applications in various fields such as touch screens, robots, smart scales, and wearable devices. The force sensors reported so far have been mainly focused on high sensitivity based on delicate microstructured materials, resulting in low reproducibility and high fabrication cost that are limitations for wide applications. As an alternative, we demonstrate a novel capacitive-type force sensor with enhanced performance owing to the increased dielectric properties of elastomers and simple sensor structure. We rationally design dielectric elastomers based on alkylamine modified-multi-walled carbon nanotube (MWCNT)/polydimethylsiloxane (PDMS) composites, which have a higher dielectric constant than pure PDMS. The alkylamine-MWCNTs show excellent dispersion in a PDMS matrix, thus leading to enhanced and reliable dielectric properties of the composites. A force sensor array fabricated with alkylamine-MWCNT/PDMS composites presents an enhanced response due to the higher dielectric constant of the composites than that of pure PDMS. This study is the first to report enhanced performance of capacitive force sensors by modulating the dielectric properties of elastomers. We believe that the disclosed strategy to improve the sensor performance by increasing the dielectric properties of elastomers has great potential in the development of capacitive force sensor arrays that respond to various input forces.Force sensors have attracted tremendous attention owing to their applications in various fields such as touch screens, robots, smart scales, and wearable devices. The force sensors reported so far have been mainly focused on high sensitivity based on delicate microstructured materials, resulting in low reproducibility and high fabrication cost that are limitations for wide applications. As an alternative, we demonstrate a novel capacitive-type force sensor with enhanced performance owing to the increased

  20. Enhanced photovoltaic properties in graphene/polycrystalline BiFeO3/Pt heterojunction structure

    Science.gov (United States)

    Zang, Yongyuan; Xie, Dan; Wu, Xiao; Chen, Yu; Lin, Yuxuan; Li, Mohan; Tian, He; Li, Xiao; Li, Zhen; Zhu, Hongwei; Ren, Tianling; Plant, David

    2011-09-01

    We report the enhanced photovoltaic properties in polycrystalline BiFeO3 (BFO) thin films with graphene as top electrodes. The short circuit current density (Jsc) and open circuit voltage of the heterojunction are measured to be 25 μA/cm2 and 0.44 V, respectively, much higher than the reported values for polycrystalline BFO with indium tin oxide (ITO) as top electrodes. Influence of HNO3 treatment on the photovoltaic properties is studied, and a significant photocurrent density improvement from 25 μA/cm2 to 2.8 mA/cm2 is observed. A metal-intrinsic semiconductor-metal model is proposed to explain the graphene induced enhancement comparing with traditional ITO.

  1. Enhanced capacitive properties of commercial activated carbon by re-activation in molten carbonates

    Science.gov (United States)

    Lu, Beihu; Xiao, Zuoan; Zhu, Hua; Xiao, Wei; Wu, Wenlong; Wang, Dihua

    2015-12-01

    Simple, affordable and green methods to improve capacitive properties of commercial activated carbon (AC) are intriguing since ACs possess a predominant role in the commercial supercapacitor market. Herein, we report a green reactivation of commercial ACs by soaking ACs in molten Na2CO3-K2CO3 (equal in mass ratios) at 850 °C combining the merits of both physical and chemical activation strategies. The mechanism of molten carbonate treatment and structure-capacitive activity correlations of the ACs are rationalized. Characterizations show that the molten carbonate treatment increases the electrical conductivity of AC without compromising its porosity and wettability of electrolytes. Electrochemical tests show the treated AC exhibited higher specific capacitance, enhanced high-rate capability and excellent cycle performance, promising its practical application in supercapacitors. The present study confirms that the molten carbonate reactivation is a green and effective method to enhance capacitive properties of ACs.

  2. Atomic Force Microscopy and pharmacology: from microbiology to cancerology.

    Science.gov (United States)

    Pillet, Flavien; Chopinet, Louise; Formosa, Cécile; Dague, Etienne

    2014-03-01

    Atomic Force Microscopy (AFM) has been extensively used to study biological samples. Researchers take advantage of its ability to image living samples to increase our fundamental knowledge (biophysical properties/biochemical behavior) on living cell surface properties, at the nano-scale. AFM, in the imaging modes, can probe cells morphological modifications induced by drugs. In the force spectroscopy mode, it is possible to follow the nanomechanical properties of a cell and to probe the mechanical modifications induced by drugs. AFM can be used to map single molecule distribution at the cell surface. We will focus on a collection of results aiming at evaluating the nano-scale effects of drugs, by AFM. Studies on yeast, bacteria and mammal cells will illustrate our discussion. Especially, we will show how AFM can help in getting a better understanding of drug mechanism of action. This review demonstrates that AFM is a versatile tool, useful in pharmacology. In microbiology, it has been used to study the drugs fighting Candida albicans or Pseudomonas aeruginosa. The major conclusions are a better understanding of the microbes' cell wall and of the drugs mechanism of action. In cancerology, AFM has been used to explore the effects of cytotoxic drugs or as an innovative diagnostic technology. AFM has provided original results on cultured cells, cells extracted from patient and directly on patient biopsies. This review enhances the interest of AFM technologies for pharmacology. The applications reviewed range from microbiology to cancerology. Copyright © 2013 Elsevier B.V. All rights reserved.

  3. Enhancing the mechanical properties of collagen by photo-chemical cross-linking

    OpenAIRE

    Shahban, S. A.; Brown, R. A.; Bozec, L.; Cheema, U.

    2009-01-01

    Cell survival within mechanically strong scaffolds is critical in the design of tissue engineered constructs. Collagen type I gels tend to be mechanically weak due to the low percentage of collagen with limited orientation and crosslinking. To enhance the properties of collagen type I gels we used the following approaches: a) plastically compress the collagen gel to increase the density and b) photochemically crosslink the gel using riboflavin as a photoinitiator and high intensity blue light...

  4. SPHERICAL CRYSTALLIZATION OF ZALTOPROFEN FOR ENHANCEMENT OF MICROMERITIC PROPERTIES AND DISSOLUTION RATE

    OpenAIRE

    E. Hari Krishna*, V. Ram Mohan Gupta and S. Jyothi

    2012-01-01

    The present work deals with the spherical crystallization process by Spherical agglomeration method applied to Zaltoprofen, a novel NSAID drug. The object of present study was to prepare and characterize the spherical agglomeration of water insoluble non-steroidal anti-inflammatory drug. Zaltoprofen spherical agglomerates prepared with poly ethylene glycol, which is hydrophilic polymer by using simple spherical agglomeration technique for enhancing micromeritic properties and dissolution rate...

  5. Electrochemical synthesis and one step modification of PMProDot nanotubes and their enhanced electrochemical properties.

    Science.gov (United States)

    Nguyen, Thao M; Cho, Seungil; Varongchayakul, Nitinun; Yoon, Daehyun; Seog, Joonil; Zong, Kyukwan; Lee, Sang Bok

    2012-03-11

    Poly (3,4-(2-methylene)propylenedioxythiophene) (PMProDot) nanotubes were synthesized within the pores of polycarbonate and were further modified with styrene and vinylcarbazole by a one step electrochemical method through the methylene functional group. The enhanced electrochemical and electrochromic properties of composite nanotubes were investigated using FTIR, UV/Vis absorbance spectroscopy, and AFM. This journal is © The Royal Society of Chemistry 2012

  6. Host-Guest Carbon Dots for Enhanced Optical Properties and Beyond

    OpenAIRE

    Ya-Ping Sun; Ping Wang; Zhuomin Lu; Fan Yang; Meziani, Mohammed J.; Gregory E. LeCroy; Yun Liu; Haijun Qian

    2015-01-01

    Carbon dots, generally small carbon nanoparticles with various forms of surface passivation, have achieved the performance level of semiconductor quantum dots in the green spectral region, but their absorption and fluorescence in red/near-IR are relatively weaker. Conceptually similar to endofullerenes, host-guest carbon dots were designed and prepared with red/near-IR dyes encapsulated as guest in the carbon nanoparticle core. Beyond the desired enhancement in optical properties, the host-gu...

  7. TiCN/TiNbCN multilayer coatings with enhanced mechanical properties

    Science.gov (United States)

    Caicedo, J. C.; Amaya, C.; Yate, L.; Gómez, M. E.; Zambrano, G.; Alvarado-Rivera, J.; Muñoz-Saldaña, J.; Prieto, P.

    2010-08-01

    Enhancement of mechanical properties by using a TiCN/TiNbCN multilayered system with different bilayer periods ( Λ) and bilayer numbers ( n) via magnetron sputtering technique was studied in this work. The coatings were characterized in terms of structural, chemical, morphological and mechanical properties by X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nanoindentation. Results of the X-ray analysis showed reflections associated to FCC (1 1 1) crystal structure for TiCN/TiNbCN films. AFM analysis revealed a reduction of grain size and roughness when the bilayer number is increased and the bilayer period is decreased. Finally, enhancement of mechanical properties was determined via nanoindentation measurements. The best behavior was obtained when the bilayer period ( Λ) was 15 nm ( n = 200), yielding the highest hardness (42 GPa) and elastic modulus (408 GPa). The values for the hardness and elastic modulus are 1.6 and 1.3 times greater than the coating with n = 1, respectively. The enhancement effects in multilayer coatings could be attributed to different mechanisms for layer formation with nanometric thickness due to the Hall-Petch effect; because this effect, originally used to explain the increase in hardness with decreasing grain size in bulk polycrystalline metals, has also been used to explain hardness enhancements in multilayers taking into account the thickness reduction at individual single layers that make the multilayered system. The Hall-Petch model based on dislocation motion within layers and across layer interfaces, has been successfully applied to multilayers to explain this hardness enhancement.

  8. TiCN/TiNbCN multilayer coatings with enhanced mechanical properties

    Energy Technology Data Exchange (ETDEWEB)

    Caicedo, J.C., E-mail: Jcesarca@calima.univalle.edu.co [Thin Film Group, Universidad del Valle, Cali (Colombia); Amaya, C. [Thin Film Group, Universidad del Valle, Cali (Colombia); Laboratory of Hard Coatings, CDT-ASTIN SENA, Cali (Colombia); Yate, L. [Department de Fisica Aplicada i Optica, Universitat de Barcelona, Catalunya (Spain); Gomez, M.E.; Zambrano, G. [Thin Film Group, Universidad del Valle, Cali (Colombia); Alvarado-Rivera, J.; Munoz-Saldana, J. [Centro de Investigacion y de Estudios Avanzados del IPN, Unidad Queretaro, Mexico (Mexico); Prieto, P. [Thin Film Group, Universidad del Valle, Cali (Colombia); Center of Excellence on Novel Materials, CENM, Calle 13 100-00 Edificio 320, espacio 1026, Cali (Colombia)

    2010-08-01

    Enhancement of mechanical properties by using a TiCN/TiNbCN multilayered system with different bilayer periods ({Lambda}) and bilayer numbers (n) via magnetron sputtering technique was studied in this work. The coatings were characterized in terms of structural, chemical, morphological and mechanical properties by X-ray diffraction (XRD), atomic force microscopy (AFM), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nanoindentation. Results of the X-ray analysis showed reflections associated to FCC (1 1 1) crystal structure for TiCN/TiNbCN films. AFM analysis revealed a reduction of grain size and roughness when the bilayer number is increased and the bilayer period is decreased. Finally, enhancement of mechanical properties was determined via nanoindentation measurements. The best behavior was obtained when the bilayer period ({Lambda}) was 15 nm (n 200), yielding the highest hardness (42 GPa) and elastic modulus (408 GPa). The values for the hardness and elastic modulus are 1.6 and 1.3 times greater than the coating with n = 1, respectively. The enhancement effects in multilayer coatings could be attributed to different mechanisms for layer formation with nanometric thickness due to the Hall-Petch effect; because this effect, originally used to explain the increase in hardness with decreasing grain size in bulk polycrystalline metals, has also been used to explain hardness enhancements in multilayers taking into account the thickness reduction at individual single layers that make the multilayered system. The Hall-Petch model based on dislocation motion within layers and across layer interfaces, has been successfully applied to multilayers to explain this hardness enhancement.

  9. Vibrational Properties of a Monolayer Silicene Sheet Studied by Tip-Enhanced Raman Spectroscopy

    Science.gov (United States)

    Sheng, Shaoxiang; Wu, Jiang-bin; Cong, Xin; Li, Wenbin; Gou, Jian; Zhong, Qing; Cheng, Peng; Tan, Ping-heng; Chen, Lan; Wu, Kehui

    2017-11-01

    Combining ultrahigh sensitivity, spatial resolution, and the capability to resolve chemical information, tip-enhanced Raman spectroscopy (TERS) is a powerful tool to study molecules or nanoscale objects. Here we show that TERS can also be a powerful tool in studying two-dimensional materials. We have achieved a 109 Raman signal enhancement and a 0.5 nm spatial resolution using monolayer silicene on Ag(111) as a prototypical 2D material system. Because of the selective enhancement on Raman modes with vertical vibrational components in TERS, our experiment provides direct evidence of the origination of Raman modes in silicene. Furthermore, the ultrahigh sensitivity of TERS allows us to identify different vibrational properties of silicene phases, which differ only in the bucking direction of the Si-Si bonds. Local vibrational features from defects and domain boundaries in silicene can also be identified.

  10. Thermodynamic Approach to Enhanced Dispersion and Physical Properties in a Carbon Nanotube/Polypeptide Nanocomposite

    Science.gov (United States)

    Lovell, Conrad S.; Wise, Kristopher E.; Kim, Jae-Woo; Lillehei, Peter T.; Harrison, Joycelyn S.; Park, Cheol

    2009-01-01

    A high molecular weight synthetic polypeptide has been designed which exhibits favorable interactions with single wall carbon nanotubes (SWCNTs). The enthalpic and entropic penalties of mixing between these two molecules are reduced due to the polypeptide's aromatic sidechains and helical secondary structure, respectively. These enhanced interactions result in a well dispersed SWCNT/Poly (L-Leucine-ran-L-Phenylalanine) nanocomposite with enhanced mechanical and electrical properties using only shear mixing and sonication. At 0.5 wt% loading of SWCNT filler, the nanocomposite exhibits simultaneous increases in the Young's modulus, failure strain, and toughness of 8%, 120%, and 144%, respectively. At one kHz, the same nanotube loading level also enhances the dielectric constant from 2.95 to 22.81, while increasing the conductivity by four orders of magnitude.

  11. Investigation of plasmon properties of silver microsphere array demonstrated experimentally by tip-enhanced Raman spectroscopy

    Science.gov (United States)

    Liu, Yanqi; Zhao, Lijiang; Li, Xinjuan; Zeng, Zhuo; Wang, Peijie; Zhang, Lisheng; Fang, Yan

    2018-01-01

    Due to high spatial resolution and extraordinarily high detection sensitivity of tip-enhanced Raman spectroscopy (TERS), it has attracted more and more attention. However, the tip size and shape, and tip substrate distance have a large impact on the TERS enhancement properties. In this study, a silver microsphere array was prepared on a Polystyrene (PS) microsphere array by vacuum thermal evaporation. And the correlation between the properties of two-dimensional surface-enhanced Raman scattering (SERS) mapping of rhodamine 6G (Rh6G) absorbed on the silver microsphere array and the polarization direction of the incident light was investigated. The effect of the location of the tip on the surface plasmon distribution of the silver microsphere array was also revealed in TERS. In addition, the surface electromagnetic field distribution of the silver microsphere array was simulated by three-dimensional finite-difference time domain (3D-FDTD) method. These results show that the distribution of 'hot spots' on the surface of the silver microsphere array has a dependency on the polarization direction of the incident laser. Moreover, with the introduction of the tip, the 'hot spot' on the surface of the silver microsphere array becomes much more localized and largely enhanced. These results obtained in this paper may have some significance for further studies on the surface plasmon resonance bio-sensing.

  12. Combining Non-Pharmacological Treatments with Pharmacotherapies for Neurological Disorders: A Unique Interface of the Brain, Drug–Device, and Intellectual Property

    Science.gov (United States)

    Bulaj, Grzegorz

    2014-01-01

    Mobile medical applications (mHealth), music, and video games are being developed and tested for their ability to improve pharmacotherapy outcomes and medication adherence. Pleiotropic mechanism of music and gamification engages an intrinsic motivation and the brain reward system, supporting therapies in patients with neurological disorders, including neuropathic pain, depression, anxiety, or neurodegenerative disorders. Based on accumulating results from clinical trials, an innovative combination treatment of epilepsy seizures, comorbidities, and the medication non-adherence can be designed, consisting of antiepileptic drugs and disease self-management software delivering clinically beneficial music. Since creative elements and art expressed in games, music, and software are copyrighted, therefore clinical and regulatory challenges in developing copyrighted, drug–device therapies may be offset by a value proposition of the exclusivity due to the patent–independent protection, which can last for over 70 years. Taken together, development of copyrighted non-pharmacological treatments (e-therapies), and their combinations with pharmacotherapies, offer incentives to chronically ill patients and outcome-driven health care industries. PMID:25071711

  13. Combining non-pharmacological treatments with pharmacotherapies for neurological disorders: a unique interface of the brain, drug-device, and intellectual property.

    Science.gov (United States)

    Bulaj, Grzegorz

    2014-01-01

    Mobile medical applications (mHealth), music, and video games are being developed and tested for their ability to improve pharmacotherapy outcomes and medication adherence. Pleiotropic mechanism of music and gamification engages an intrinsic motivation and the brain reward system, supporting therapies in patients with neurological disorders, including neuropathic pain, depression, anxiety, or neurodegenerative disorders. Based on accumulating results from clinical trials, an innovative combination treatment of epilepsy seizures, comorbidities, and the medication non-adherence can be designed, consisting of antiepileptic drugs and disease self-management software delivering clinically beneficial music. Since creative elements and art expressed in games, music, and software are copyrighted, therefore clinical and regulatory challenges in developing copyrighted, drug-device therapies may be offset by a value proposition of the exclusivity due to the patent-independent protection, which can last for over 70 years. Taken together, development of copyrighted non-pharmacological treatments (e-therapies), and their combinations with pharmacotherapies, offer incentives to chronically ill patients and outcome-driven health care industries.

  14. Combining Non-pharmacological Treatments with Pharmacotherapies for Neurological Disorders: a Unique Interface of the Brain, Drug-Device and Intellectual Property

    Directory of Open Access Journals (Sweden)

    Grzegorz eBulaj

    2014-07-01

    Full Text Available Mobile medical applications (mHealth, music and video games are being developed and tested for their ability to improve pharmacotherapy outcomes and medication adherence. Pleiotropic mechanism of music and gamification engage an intrinsic motivation and the brain reward system, supporting therapies in patients with neurological disorders, including neuropathic pain, depression, anxiety, or neurodegenerative disorders. Based on accumulating results from clinical trials, an innovative combination treatment of epilepsy seizures, comorbidities and the medication non-adherence can be designed, consisting of antiepileptic drugs and disease self-management software delivering clinically beneficial music. Since creative elements and art expressed in games, music and software are copyrighted, therefore clinical and regulatory challenges in developing copyrighted, drug-device therapies may be offset by a value proposition of the exclusivity due to the patent-independent protection which can last for over 70 years. Taken together, development of copyrighted non-pharmacological treatments (e-therapies, and their combinations with pharmacotherapies, offers incentives to chronically-ill patients and outcome-driven health care industries.

  15. Ethnobotanical review and pharmacological properties of selected medicinal plants in Brunei Darussalam: Litsea elliptica, Dillenia suffruticosa, Dillenia excelsa, Aidia racemosa, Vitex pinnata and Senna alata

    National Research Council Canada - National Science Library

    Goh, May Poh Yik; Basri, Aida Maryam; Yasin, Hartini; Taha, Hussein; Ahmad, Norhayati

    2017-01-01

    The aim of the current study is to review the medicinal properties of the plants found in Brunei Darussalam namely Litsea elliptica, Dillenia suffruticosa, Dillenia excelsa, Aidia racemosa, Vitex pinnata and Senna alata...

  16. Nanostructured interfaces for enhancing mechanical properties of composites: Computational micromechanical studies

    DEFF Research Database (Denmark)

    Mishnaevsky, Leon

    2015-01-01

    . Several groups of materials (composites, nanocomposites, nanocrystalline metals, wood) are considered with view on the effect of nanostructured interfaces on their properties. The structures of various nanostructured interfaces (protein structures and mineral bridges in biopolymers in nacre......Computational micromechanical studies of the effect of nanostructuring and nanoengineering of interfaces, phase and grain boundaries of materials on the mechanical properties and strength of materials and the potential of interface nanostructuring to enhance the materials properties are reviewed...... and microfibrils in wood; pores, interphases and nanoparticles in fiber/matrix interfaces of polymer fiber reinforced composites and nanocomposites; dislocations and precipitates in grain boundaries of nanocrystalline metals) and the methods of their modeling are discussed. It is concluded that nanostructuring...

  17. Chicken feathers as a natural source of sulphur to develop sustainable protein films with enhanced properties.

    Science.gov (United States)

    Garrido, Tania; Leceta, Itsaso; de la Caba, Koro; Guerrero, Pedro

    2018-01-01

    In this work, the effect of hydrolyzed keratin on the properties of soy protein-based films was analyzed when different manufacture processes were employed. It is widely known that the processing method selected can affect the film properties as a function of the structure obtained during the film formation. Therefore, the assessment of hydrolyzed keratin/soy protein films processed by casting and compression moulding was carried out by means of the analysis of physicochemical, thermal, mechanical, optical and surface properties. It was observed that the incorporation of hydrolyzed keratin, obtained from a simpler, environmentally friendlier and more sustainable extraction method, resulted in the improvement of the thermal stability of the films, irrespective of the processing method employed. Moreover, the films processed by compression moulding showed enhanced tensile strength, which increased with the incorporation of hydrolyzed keratin due to the formation of disulfide bonds. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Porous Polyelectrolyte Hydrogels With Enhanced Swelling Properties Prepared Via Thermal Reverse Casting Technique

    Science.gov (United States)

    Salerno, Aurelio; Netti, Paolo A.

    2010-06-01

    In this work we investigated the preparation and characterization of porous polyelectrolyte hydrogels via thermal reverse casting technique. Polyacrylamide hydrogels were synthesized by free-radical crosslinking polymerization into the space of an agarose gel which, after the setting of the chemical gel, was removed to allow the formation of an interconnected porosity pathway. Two different monomer/agarose solution ratios were selected for the reverse casting process and, the resulting hydrogels characterized in terms of morphological, micro-structural and thermal properties, as well as swelling capability in solutions at different ionic strength. The results of this study demonstrated that proposed technique allowed the design of porous polyacrylamide hydrogels with well controlled pore structures. Furthermore, if compared to non porous polyacrylamide hydrogel, the as obtained hydrogels were characterized by enhanced swelling properties and that, these properties were fine tuned by the appropriate selection of the templating agent concentration.

  19. Preparation of Basalt Incorporated Polyethylene Composite with Enhanced Mechanical Properties for Various Applications

    Directory of Open Access Journals (Sweden)

    Bredikhin Pavel

    2017-01-01

    Full Text Available The present article showed the possibility of increasing the complex of mechanical properties of polyolefins with dispersed mineral fillers obtained by fine grinding of basalt rocks via ball mill processing. The composites based on dispersed basalt, which were derived from Samara rock mass (Russia with rare earth elements containing, were obtained by extrusion combining the binder and filler, followed by preparation injection-molded test samples. The study of mechanical properties of materials developed showed the possibility of a significant increase in strength characteristics of different types of polyethylene: the breaking stress at static bending for HDPE can be increasing more than 60% and the impact strength by more than 4 times. In addition the incorporation of the dispersed basalt also enhanced the thermal properties of the composites (the oxygen index of HDPE increases from 19 to 25%.

  20. [Pharmacological treatment of dyslexia].

    Science.gov (United States)

    Artigas-Pallarés, J

    Pharmacological approaches aimed at improving dyslexia are almost inexistent. To analyse, based on the current theories of dyslexia, the possibility of applying some pharmacological measure. The different theories on dyslexia are discussed. The multiple deficit model is then outlined, in opposition to the classical single dysfunction model. The model described provides a coherent explanation for several conceptual dilemmas that arise from the analysis of the comorbidity of dyslexia. The few pharmacological interventions that have been proposed to date are also analysed; with the exception of stimulants, however, they are not supported by any solid theoretical base about dyslexia. Lastly, we use the multiple deficit model as an aid to analyse the current data referring to the effect of stimulants on nuclear mechanisms in dyslexia. It is suggested that it would be wise to monitor the response in reading skills in children with dyslexia and attention deficit hyperactivity disorder (ADHD) who are being treated with stimulants. We also recommend taking into consideration the comorbidity between dyslexia and ADHD as an argument in favour of pharmacological intervention in patients with apparently mild symptoms of ADHD. In any case, today, pharmacological intervention cannot be expected to go beyond its having a complementary and synergic effect on traditional methods of treatment.

  1. Enhanced properties of tungsten thin films deposited with a novel HiPIMS approach

    Science.gov (United States)

    Velicu, Ioana-Laura; Tiron, Vasile; Porosnicu, Corneliu; Burducea, Ion; Lupu, Nicoleta; Stoian, George; Popa, Gheorghe; Munteanu, Daniel

    2017-12-01

    Despite the tremendous potential for industrial use of tungsten (W), very few studies have been reported so far on controlling and tailoring the properties of W thin films obtained by physical vapor deposition techniques and, even less, for those deposited by High Power Impulse Magnetron Sputtering (HiPIMS). This study presents results on the deposition process and properties characterization of nanocrystalline W thin films deposited on silicon and molybdenum substrates (100 W average sputtering power) by conventional dc magnetron sputtering (dcMS) and HiPIMS techniques. Topological, structural, mechanical and tribological properties of the deposited thin films were investigated. It was found that in HiPIMS, both deposition process and coatings properties may be optimized by using an appropriate magnetic field configuration and pulsing design. Compared to the other deposited samples, the W films grown in multi-pulse (5 × 3 μs) HiPIMS assisted by an additional magnetic field, created with a toroidal-shaped permanent magnet placed in front of the magnetron cathode, show significantly enhanced properties, such as: smoother surfaces, higher homogeneity and denser microstructure, higher hardness and Young's modulus values, better adhesion to the silicon substrate and lower coefficient of friction. Mechanical behaviour and structural changes are discussed based on plasma diagnostics results.

  2. Compaction enhances extracellular matrix content and mechanical properties of tissue-engineered cartilaginous constructs.

    Science.gov (United States)

    Han, EunHee; Ge, Chenghao; Chen, Albert C; Schumacher, Barbara L; Sah, Robert L

    2012-06-01

    Many cell-based tissue-engineered cartilaginous constructs are mechanically softer than native tissue and have low content and abnormal proportions of extracellular matrix (ECM) constituents. We hypothesized that the load-bearing mechanical properties of cartilaginous constructs improve with the inclusion of collagen (COL) and proteoglycan (PG) during assembly. The objectives of this work were to determine (1) the effect of addition of PG, COL, or COL+PG on compressive properties of 2% agarose constructs and (2) the ability of mechanical compaction to concentrate matrix content and improve the compressive properties of such constructs. The inclusion of COL+PG improved the compressive properties of hydrogel constructs compared with PG or COL alone. Mechanical compaction increased the PG and COL concentrations in and compressive stiffness of the constructs. Chondrocytes included in the constructs maintained high viability after compaction. These results support the concepts that the assembly of cartilaginous constructs with COL+PG and application of mechanical compaction enhance the ECM content and compressive properties of engineered cartilaginous constructs.

  3. Pharmacological Investigation of Selected Medicinal Plants of ...

    African Journals Online (AJOL)

    Purpose: To pharmacologically investigate the methanol and petroleum ether extracts of the plant leaves of ... medicinal properties in local floristic resources. ..... 2nd edition ed. 2003: Asiatic. Society of Bangladesh; p 138. 2. Mohiddin YBH, Chin W, Worth DH. Traditional Medicinal. Plants of Brunei Darussalam Part III.

  4. Phytochemical, pharmacological and biological profiles of Tragia ...

    African Journals Online (AJOL)

    Methods: The reported data/information was retrieved mainly from the online databases of PubMed (MEDLINE), EMBASE and Botanical Survey of India. Results: The present review elaborated the phytochemical, pharmacological and biological properties of the selected five Tragia species obtained from recent literature.

  5. Nanocomposites biodegradable coating on BOPET films to enhance hot seal strength properties

    Science.gov (United States)

    Barbaro, G.; Galdi, M. R.; Di Maio, L.; Incarnato, L.

    2015-12-01

    The coating technology is a strategic solution to improve the properties of flexible packaging films. Indeed, additional functional layers are often designed and added as coating on the substrate, in order to improve the characteristic of the flexible packaging and to meet the requirements for the desired gas or vapour barrier, for adhesion and sealing, or for improving the film printability, its aesthetics and durability. Moreover, this technology allows to functionalize a polymeric substrate applying materials with different chemistry, rheology, thermal and structural characteristics. BOPET films are widely used for food packaging applications thanks to their good gas barrier and mechanical properties, high transparency and for the excellent printability. In regard to sealing performance, BOPET films show poor sealing properties so they are mostly submitted to lamination processes with polyethylene. Nevertheless, this solution compromises the PET recyclability and influences the gas permeability of the multilayer PET based structures. The aim of this work is to investigate on the effect of nanocomposite biodegradable coatings for BOPET substrates in enhancing the heat sealing strength of eco-compatible PET/PLA films. At this regards, different percentages of Cloisite C30B (0%, 2% and 4%wt/wt) have been added to PLA by solution intercalation technique and the nanocomposite biodegradable materials produced have been applied on BOPET commercial films by casting. The BOPET coated films have been characterized in order to evaluate the heat sealing strength and the mechanical, gas permeability and surface properties. The results have shown that the addition of nanoclay in PLA coating significantly enhance the hot tack properties of the PET/PLA system produced, while the oxygen and water vapour permeability are slightly increased if compared to pure BOPET films.

  6. Nanocomposites biodegradable coating on BOPET films to enhance hot seal strength properties

    Energy Technology Data Exchange (ETDEWEB)

    Barbaro, G., E-mail: giovannibarbaro@email.it; Galdi, M. R., E-mail: mrgaldi@unisa.it; Di Maio, L., E-mail: ldimaio@unisa.it; Incarnato, L., E-mail: lincarnato@unisa.it [Industrial Engineering Department, University of Salerno, Via Giovanni Paolo II 132, 84084 Fisciano (Italy)

    2015-12-17

    The coating technology is a strategic solution to improve the properties of flexible packaging films. Indeed, additional functional layers are often designed and added as coating on the substrate, in order to improve the characteristic of the flexible packaging and to meet the requirements for the desired gas or vapour barrier, for adhesion and sealing, or for improving the film printability, its aesthetics and durability. Moreover, this technology allows to functionalize a polymeric substrate applying materials with different chemistry, rheology, thermal and structural characteristics. BOPET films are widely used for food packaging applications thanks to their good gas barrier and mechanical properties, high transparency and for the excellent printability. In regard to sealing performance, BOPET films show poor sealing properties so they are mostly submitted to lamination processes with polyethylene. Nevertheless, this solution compromises the PET recyclability and influences the gas permeability of the multilayer PET based structures. The aim of this work is to investigate on the effect of nanocomposite biodegradable coatings for BOPET substrates in enhancing the heat sealing strength of eco-compatible PET/PLA films. At this regards, different percentages of Cloisite C30B (0%, 2% and 4%{sub wt/wt}) have been added to PLA by solution intercalation technique and the nanocomposite biodegradable materials produced have been applied on BOPET commercial films by casting. The BOPET coated films have been characterized in order to evaluate the heat sealing strength and the mechanical, gas permeability and surface properties. The results have shown that the addition of nanoclay in PLA coating significantly enhance the hot tack properties of the PET/PLA system produced, while the oxygen and water vapour permeability are slightly increased if compared to pure BOPET films.

  7. Incorporation of a Decorin Biomimetic Enhances the Mechanical Properties of Electrochemically Aligned Collagen Threads

    Science.gov (United States)

    Kishore, Vipuil; Paderi, John E.; Akkus, Anna; Smith, Katie M.; Balachandran, Dave; Beaudoin, Stephen; Panitch, Alyssa; Akkus, Ozan

    2011-01-01

    Orientational anisotropy of collagen molecules is integral for the mechanical strength of collagen-rich tissues. We have previously reported a novel methodology to synthesize highly oriented electrochemically aligned collagen (ELAC) threads with mechanical properties converging upon those of native tendon. Decorin, a small leucine rich proteoglycan (SLRP), binds to fibrillar collagen and has been suggested to enhance the mechanical properties of tendon. Based on the structure of natural decorin, we have previously designed and synthesized a peptidoglycan (DS-SILY) that mimics decorin both structurally and functionally. In this study, we investigated the effect of the incorporation of DS-SILY on the mechanical properties and structural organization of ELAC threads. The results indicated that the addition of DS-SILY at a molar ratio of 30:1 (Collagen:DS-SILY) significantly enhanced the ultimate stress and ultimate strain of the ELAC threads. Furthermore, differential scanning calorimetry revealed that the addition of DS-SILY at a molar ratio of 30:1 resulted in a more thermally stable collagen structure. However, addition of DS-SILY at a higher concentration (10:1 Collagen:DS-SILY) yielded weaker threads with mechanical properties comparable to collagen control threads. Transmission emission microscopy revealed that the addition of DS-SILY at a higher concentration (10:1) resulted in pronounced aggregation of collagen fibrils. More importantly, these aggregates were not aligned along the long axis of the ELAC thereby compromising on the overall tensile properties of the material. We conclude that incorporation of an optimal amount of DS-SILY is a promising approach to synthesize mechanically competent collagen based biomaterials for tendon tissue engineering applications. PMID:21356334

  8. Enhanced antibacterial properties, biocompatibility, and corrosion resistance of degradable Mg-Nd-Zn-Zr alloy.

    Science.gov (United States)

    Qin, Hui; Zhao, Yaochao; An, Zhiquan; Cheng, Mengqi; Wang, Qi; Cheng, Tao; Wang, Qiaojie; Wang, Jiaxing; Jiang, Yao; Zhang, Xianlong; Yuan, Guangyin

    2015-06-01

    Magnesium (Mg), a potential biodegradable material, has recently received increasing attention due to its unique antibacterial property. However, rapid corrosion in the physiological environment and potential toxicity limit clinical applications. In order to improve the corrosion resistance meanwhile not compromise the antibacterial activity, a novel Mg alloy, Mg-Nd-Zn-Zr (Hereafter, denoted as JDBM), is fabricated by alloying with neodymium (Nd), zinc (Zn), zirconium (Zr). pH value, Mg ion concentration, corrosion rate and electrochemical test show that the corrosion resistance of JDBM is enhanced. A systematic investigation of the in vitro and in vivo antibacterial capability of JDBM is performed. The results of microbiological counting, CLSM, SEM in vitro, and microbiological cultures, histopathology in vivo consistently show JDBM enhanced the antibacterial activity. In addition, the significantly improved cytocompatibility is observed from JDBM. The results suggest that JDBM effectively enhances the corrosion resistance, biocompatibility and antimicrobial properties of Mg by alloying with the proper amount of Zn, Zr and Nd. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Enhancement of transport properties of a Brownian particle due to quantum effects: Smoluchowski limit

    Energy Technology Data Exchange (ETDEWEB)

    Shit, Anindita [Department of Chemistry, Bengal Engineering and Science University, Shibpur, Howrah 711103 (India); Chattopadhyay, Sudip, E-mail: sudip_chattopadhyay@rediffmail.com [Department of Chemistry, Bengal Engineering and Science University, Shibpur, Howrah 711103 (India); Chaudhuri, Jyotipratim Ray, E-mail: jprc_8@yahoo.com [Department of Physics, Katwa College, Katwa, Burdwan 713130 (India)

    2012-03-13

    Graphical abstract: By invoking physically motivated coordinate transformation into quantum Smoluchowski equation, we have presented a transparent treatment for the determination of the effective diffusion coefficient and current of a quantum Brownian particle. Substantial enhancement in the efficiency of the diffusive transport is envisaged due to the quantum correction effects. Highlights:: Black-Right-Pointing-Pointer Transport of a quantum Brownian particle in a periodic potential has been addressed. Black-Right-Pointing-Pointer Governing quantum Smoluchowski equation (QSE) includes state dependent diffusion. Black-Right-Pointing-Pointer A coordinate transformation is used to recast QSE with constant diffusion. Black-Right-Pointing-Pointer Transport properties increases in comparison to the corresponding classical result. Black-Right-Pointing-Pointer This enhancement is purely a quantum effect. - Abstract: The transport property of a quantum Brownian particle that interacts strongly with a bath (in which a typical damping constant by far exceeds a characteristic frequency of the isolated system) under the influence of a tilted periodic potential has been studied by solving quantum Smoluchowski equation (QSE). By invoking physically motivated coordinate transformation into QSE, we have presented a transparent treatment for the determination of the effective diffusion coefficient of a quantum Brownian particle and the current (the average stationary velocity). Substantial enhancement in the efficiency of the diffusive transport is envisaged due to the quantum correction effects only if the bath temperature hovers around an appropriate range of intermediate values. Our findings also confirm the results obtained in the classical cases.

  10. Water-processed carbon nanotube/graphene hybrids with enhanced field emission properties

    Directory of Open Access Journals (Sweden)

    Meng Song

    2015-09-01

    Full Text Available Integrating carbon nanotubes (CNTs and graphene into hybrid structures provides a novel approach to three dimensional (3D materials with advantageous properties. Here we present a water-processing method to create integrated CNT/graphene hybrids and test their field emission properties. With an optimized mass ratio of CNTs to graphene, the hybrid shows a significantly enhanced field emission performance, such as turn-on electric field of 0.79 V/μm, threshold electric field of 1.05 V/μm, maximum current density of 0.1 mA/cm2, and field enhancement factor of ∼1.3 × 104. The optimized mass ratio for field emission emphasizes the importance of both CNTs and graphene in the hybrid. We also hypothesize a possible mechanism for this enhanced field emission performance from the CNT/graphene hybrid. During the solution treatment, graphene oxide behaves as surfactant sheets for CNTs to form a well dispersed solution, which leads to a better organized 3D structure with more conducting channels for electron transport.

  11. Enhanced organic photovoltaic properties via structural modifications in PEDOT:PSS due to graphene oxide doping

    Energy Technology Data Exchange (ETDEWEB)

    Goutham, Raj P.; Sandhya, Rani V.; Kanwat, Anil; Jang, Jin, E-mail: jjang@khu.ac.kr

    2016-02-15

    Highlights: • Graphene oxide(GO) blended with PEDOT:PSS is used as HTL for PTB7:PCBM BHJ solar cells. • Increase in conductivity due to structural alterations in PEDOT:PSS by GO addition. • The structural alterations are reaveled under Raman spectroscopy, XPS and AFM. • PEDOT:PSS changed to extended coil due to addition of GO to PEDOT:PSS. • Enhanced conductivity after GO addition to PEDOT:PSS resulted in enhanced PCE. - Abstract: Poly(3,4-thylenedioxythiophene):poly(styrene sulfonate), PEDOT:PSS is a well-known conductive polymer for hole transport in organic devices, the properties of which can be enhanced by doping. Common dopants are metal oxides and nanoparticles. In this study, addition of graphene oxide (GO) to PEDOT:PSS as a dopant is addressed in organic photovoltaics (OPVs). With GO doping, electrical conductivity and transport properties of PEDOT:PSS increases due to structural alterations in the presence of −COOH and −OH functional groups in GO. These structural alterations have been revealed under detailed study of Raman spectra, X-ray photoelectron spectroscopy (XPS) analysis, Topographical and conductive Atom force microscopy (AFM/C-AFM) mapping. OPVs fabricated using PEDOT:PSS: GO (5:1) as a hole transport layer (HTL) exhibited a power conversion efficiency (PCE) of 7.68%, which was higher than the 7.01% that was obtained for the OPVs using pristine PEDOT:PSS.

  12. Molecular sensitized GdF3:Eu3+ for color tuning and highly enhanced luminescent properties.

    Science.gov (United States)

    Su, Yiguo; Lang, Junyu; Guan, Kai; Han, Dan; Du, Chunfang; Wang, Xiaojing

    2013-10-01

    In this work, we report on the preparation of [2,3-f]pyrazino[1,10]phenanthroline-2,3-dicarboxylic anions (PPDB(2-)) modified GdF3:Eu(3+) nanocrystals by a versatile ligand exchange approach for highly enhanced luminescent properties. The samples were carefully characterized by X-ray powder diffraction, transmission electron microscopy, infrared spectra and photoluminescence. It is found that all GdF3:Eu(3+) nanoparticles were entirely composed of homogeneous nano-spheres with an average diameter of about 30-35 nm. After PPDB(2-) capping, GdF3:Eu(3+) nanocrystals exhibited higher color purity and shorter lifetime time, which can be well recognized as a consequence of surface structure modification and local symmetry alteration near Eu(3+) ions. High color purity and short lifetime of PPDB(2-) modified GdF3:Eu(3+) nanocrystals predict highly enhanced red luminescence, which showed the quantum efficiency of ~34%. The highly enhanced luminescent property enables its potential application as chemosensor for detection of heavy metal ions. Copyright © 2013 Elsevier Inc. All rights reserved.

  13. Water-processed carbon nanotube/graphene hybrids with enhanced field emission properties

    Science.gov (United States)

    Song, Meng; Xu, Peng; Song, Yenan; Wang, Xu; Li, Zhenhua; Shang, Xuefu; Wu, Huizhen; Zhao, Pei; Wang, Miao

    2015-09-01

    Integrating carbon nanotubes (CNTs) and graphene into hybrid structures provides a novel approach to three dimensional (3D) materials with advantageous properties. Here we present a water-processing method to create integrated CNT/graphene hybrids and test their field emission properties. With an optimized mass ratio of CNTs to graphene, the hybrid shows a significantly enhanced field emission performance, such as turn-on electric field of 0.79 V/μm, threshold electric field of 1.05 V/μm, maximum current density of 0.1 mA/cm2, and field enhancement factor of ˜1.3 × 104. The optimized mass ratio for field emission emphasizes the importance of both CNTs and graphene in the hybrid. We also hypothesize a possible mechanism for this enhanced field emission performance from the CNT/graphene hybrid. During the solution treatment, graphene oxide behaves as surfactant sheets for CNTs to form a well dispersed solution, which leads to a better organized 3D structure with more conducting channels for electron transport.

  14. Halogenated salicylaldehyde azines: The heavy atom effect on aggregation-induced emission enhancement properties

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Xiao-tong, E-mail: chenxiaotong@tsinghua.edu.cn [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Tong, Ai-jun [Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology (Ministry of Education), Department of Chemistry, Tsinghua University, Beijing 100084 (China)

    2014-01-15

    This study investigates the heavy-atom effect (HAE) on aggregation-induced emission enhancement (AIEE) properties of salicylaldehyde azines. For this purpose, a series of halogenated salicylaldehyde azine derivatives, namely, chloro-salicylaldehyde azine (1), bromo-salicylaldehyde azine (2) and iodo-salicylaldehyde azine (3) are synthesized. 1 and 2 display typical AIEE characteristics of salicylaldehyde azine compounds; whereas for the iodo-substituent in 3, is found to be effective “external” heavy atom quenchers to salicylaldehyde azine fluorescence in aggregated state. Based on its weak fluorescence in aggregated state and relative strong fluorescence in dispersed state, 3 can also be applied as a turn-on fluorescence probe for egg albumin detection attributed to hydrophobic interaction. -- Highlights: • This study investigates the heavy-atom effect (HAE) on aggregation-induced emission enhancement (AIEE) properties of salicylaldehyde azines. • Chloro- and bromo-salicylaldehyde display typical AIEE properties of salicylaldehyde azine, whereas the iodo-substitute quenches AIEE in aggregated state. • Iodo-salicylaldehyde can be applied as a turn-on fluorescence probe for egg albumin detection attributed to hydrophobic interaction.

  15. Single-step, high yield synthesis of gold nanoworms and their surface enhanced Raman scattering properties

    Science.gov (United States)

    Ahmed, Waqqar; van Ruitenbeek, Jan M.

    Rod-shaped gold nanoparticles have attracted enormous attention owing to their interesting optical properties arising from the surface plasmon resonances. Slight deviation from the rod morphology can markedly change the optical properties. For-example, worm-shaped gold nanoparticles can have more than two plasmon peaks. Furthermore, they show much higher local field enhancements as compared to their rod-shaped counterparts. We have devised a simple seedless, high-yield protocol for the synthesis of gold nanoworms (NWs). NWs were grown simply by reducing HAuCl4 with ascorbic acid in a high pH reaction medium, and in the presence of growth directional agents, cetyltrimethylammonium bromide and AgNO3. In contrast to the seed-mediated growth of gold nanorods where a seed grows into a rod, NWs grow by oriental attachment of nanoparticles. By varying different reaction parameters we were able to control the length of NWs from a few nanometers to micrometers. Furthermore, the aspect ratio can also be tuned over a wide range. Gold NWs show excellent surface enhanced Raman scattering (SERS) properties. Ultra-low concentrations of various target molecules were detected using NWs based SERS substrates.

  16. Enhancing the functional properties and nutritional quality of ice cream with processed amla (Indian gooseberry).

    Science.gov (United States)

    Goraya, Rajpreet Kaur; Bajwa, Usha

    2015-12-01

    Amla (Indian gooseberry) and its processed products are rich source of vitamin C, phenols, dietary fibre and antioxidants. In contrast, ice cream is a poor source of these phytochemicals and antioxidants; therefore, the present investigation was undertaken to enhance the functional properties and nutritional quality of ice cream with the incorporation of processed amla. Ice cream was prepared using amla shreds, pulp, preserve and candy at 5 to 20 % and powder at 0.5 to 2.0 % levels in ice cream mix prior to freezing. Inclusion of amla products at augmented levels resulted in significant changes in physico-chemical properties and phytochemical content of ice cream. The total solids decreased on addition of shreds and pulp and increased with preserve, candy and powder in ice cream at increasing levels. The functional constituents i.e. fibre, total phenols, tannins, ascorbic acid and antioxidant activity increased with greater level of inclusion. Incorporation of processed amla raised the melting resistance of ice cream and decreased the overrun. The samples with 5 % shreds and pulp, 10 % preserve and candy and 0.5 % powder were found to have highest overall acceptability scores. Inclusion of amla in all the forms i.e. shreds, pulp, preserve, candy and powder enhanced the functional properties and nutritional value of ice cream.

  17. Cellulose Acetate/N-TiO2 Biocomposite Flexible Films with Enhanced Solar Photochromic Properties

    Science.gov (United States)

    Radhika, T.; Anju, K. R.; Silpa, M. S.; Ramalingam, R. Jothi; Al-Lohedan, Hamad A.

    2017-07-01

    Flexible cellulose acetate/N-TiO2 nanocomposite films containing various concentrations of nanosized N-TiO2 and an intelligent methylene blue ink have been prepared by solution casting. The hydrothermally prepared nitrogen-doped titania (N-TiO2) and the films were characterized in detail. The photochromic properties of the prepared films were investigated under ultraviolet (UV), visible light, and simulated solar irradiation by UV-Vis spectrophotometry. Upon irradiation, the films exhibited rapid photochromic response that was reversible at room temperature. Films with higher content of nano N-TiO2 showed enhanced decoloration/recoloration under all irradiation conditions, with fast decoloration/recoloration under simulated solar irradiation. These results suggest that the amount of nano N-TiO2 in the composite, the concentration of methylene blue, and the solvent greatly influence the photochromic properties of the films. Such flexible and transparent cellulose acetate/N-TiO2 films with enhanced decoloration/recoloration properties under solar irradiation are promising smart materials for use in photoreversible printed electronics applications.

  18. Electrospun biphasic tubular scaffold with enhanced mechanical properties for vascular tissue engineering.

    Science.gov (United States)

    Abdal-Hay, Abdalla; Bartnikowski, Michal; Hamlet, Stephen; Ivanovski, Sašo

    2018-01-01

    Polymer scaffolds produced through an electrospinning process are frequently explored as tissue substitutes for regenerative medicine. Despite offering desirable surface area to volume ratios and tailorable pore sizes, their poor structural mechanical properties limit their applicability in load-bearing regions. In this study, we present a simple strategy to improve the mechanical properties of a vascular graft scaffold. We achieved the formation of biphasic tubular scaffolds by electrospinning polyurethane (PU) onto an airbrushed tube made of polycaprolactone (PCL). After preparation, the scaffold was subsequently thermally-crosslinked (60°C) to strengthen the bonding between the two materials. The tensile strength and tensile elastic (Young's) modulus of the biphasic scaffolds were significantly enhanced from 4.5±1.72 and 45±15MPa (PU-only) up to 67.5±2.4 and 1039±81.8MPa (PCL/PU; pmechanically robust vascular graft scaffold using a novel combination of well-established fabrication techniques. This study could also be extended to the fabrication of other biphasic scaffolds to better enhance the mechanical properties of the electrospun fibers mat without deteriorating its architecture structure. Copyright © 2017 Elsevier B.V. All rights reserved.

  19. Preparation and Characterization of Mo Doped in BiVO₄ with Enhanced Photocatalytic Properties.

    Science.gov (United States)

    Liu, Bitao; Yan, Xuelian; Yan, Hengqing; Yao, Yucen; Cai, Yanhua; Wei, Jumeng; Chen, Shanyong; Xu, Xuhui; Li, Lu

    2017-08-21

    Molybdenum (Mo) doped BiVO₄ was fabricated via a simple electrospun method. Morphology, structure, chemical states and optical properties of the obtained catalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), UV-vis diffuse reflectance spectroscopy (DRS), N₂ adsorption-desorption isotherms (BET) and photoluminescence spectrum (PL), respectively. The photocatalytic properties indicate that doping Mo into BiVO₄ can enhance the photocatalytic activity and dark adsorption ability. The photocatalytic test suggests that the 1% Mo-BiVO₄ shows the best photocatalytic activity, which is about three times higher than pure BiVO₄. Meanwhile, 3% Mo-BiVO₄ shows stronger dark adsorption than pure BiVO₄ and 1% Mo-BiVO₄. The enhancement in photocatalytic property should be ascribed to that BiVO₄ with small amount of Mo doping could efficiently separate the photogenerated carries and improve the electronic conductivity. The high concentration doping would lead the crystal structure transformation from monoclinic to tetragonal phase, as well as the formation of MoO₃ nanoparticles on the BiVO₄ surface, which could also act as recombination centers to decrease the photocatalytic activity.

  20. Assessment the possibility of enhancing the tribological properties of the ferritic-austenitic cast steel

    Directory of Open Access Journals (Sweden)

    A. Brodziak

    2010-01-01

    Full Text Available The purpose of the research was to explore the possibility of enhancing the tribological properties of the ferritic-austenitic cast steel which is widely used in combustion gas desulphurization systems in the power industry. The subject of the research is the GX2CrNiMoN25-6-3 cast steel, a material for making pump rotors and other parts intended for operation at a temperature of up to 70°C in a water suspension containing Cl- and SO4-2 ions and sand / gypsum particles. It seems that in some applications, at low dynamics of parts’ operation and a predominance of erosive phenomena over corrosive ones, there is a potential for using the σ phase as a structural constitu-ent that enhances the tribological properties. However, due to the increased brittleness of the material, a need arises for optimizing the quantity of this phase and carrying out detailed research into the morphology of precipitates. To describe the tribological properties, the testing of the erosive and corrosive wear mechanism was used, which was carried out on a test stand of the authors' own construction. Metallographic and stereological examinations and hardness tests were performed, which enabled the understanding of the successive stages of tribological wear of the cast steel under investigation. The increasing volumetric share of the σ phase advantageously influenced the erosive wear resistance of the material.

  1. POSS-Containing Bioinspired Adhesives with Enhanced Mechanical and Optical Properties for Biomedical Applications.

    Science.gov (United States)

    Pramudya, Irawan; Rico, Catalina G; Lee, Choogon; Chung, Hoyong

    2016-12-12

    A new terpolymer adhesive, poly(2-methoxyethyl acrylate-co-N-methacryloyl 3,4-dihydroxyl-l-phenylalanine-co-heptaisobutyl substituted polyhedral oligomeric silsesquioxane propyl methacrylate) (poly(MEA-co-MDOPA-co-MPOSS) was synthesized by thermally initiated radical polymerization. In this study, we investigated the effect of the POSS component on adhesion, mechanical, and optical properties of the catechol-group containing bioinspired adhesives. The terpolymer contains the catechol group which is known to improve the adhesion properties of polymers. Only a very small amount of the POSS-containing monomer, MPOSS, was included, 0.5 mol %. In the presence of POSS, the synthesized poly(MEA-co-MDOPA-co-MPOSS) demonstrated strong adhesion properties, 23.2 ± 6.2 J/m2 with 0.05 N preloading and 300 s holding time, compared to many previously prepared catechol-containing adhesives. The mechanical properties (Young's modulus and stress at 10% strain) of the POSS-containing terpolymer showed significant increases (6-fold higher) over the control polymer, which does not contain POSS. Optical transmittance of the synthesized terpolymer was also improved significantly in the visible light range, 450-750 nm. Cell testing with human embryonic kidney cells (HEK293A) indicates that the new terpolymer is a promising candidate in biomedical adhesives without acute cytotoxicity. The synthesized poly(MEA-co-MDOPA-co-MPOSS) is the first example of POSS-containing pressure sensitive bioinspired adhesive for biomedical applications. The study of poly(MEA-co-MDOPA-co-MPOSS) demonstrated a convenient method to enhance two important properties, mechanical and optical properties, by the addition of a very small amount of POSS. Based on this study, it was found that POSS can be used to strengthen mechanical properties of bioinspired adhesive without the need for a covalent cross-linking step.

  2. PHARMACOLOGICAL AND THERAPEUTIC IMPORTANCE OF ERIGERON CANADENSIS (SYN: CONYZA CANADENSIS)

    OpenAIRE

    Ali Esmail Al-Snafi

    2017-01-01

    Phytochemical studies revealed that Erigeron canadensis (syn. Conyza canadensis) contained saponins, diterpenoids, terpenoids, glycosides, tannin, anthraquinone, steroids and flavonoids. Pharmacological studies showed that Erigeron canadensis exerted antimicrobial, antioxidant, anticoagulant, antiinflammatory, anticancer, mutagenic gastric protective effect and skin depigmentation activity. The current review discussed the phytochemical and pharmacological properties of Erigeron c...

  3. The concise guide to pharmacology 2017/18: Overview

    NARCIS (Netherlands)

    Alexander, Stephen Ph; Kelly, Eamonn; Marrion, Neil V.; Peters, John A.; Faccenda, Elena; Harding, Simon D.; Pawson, Adam J.; Sharman, Joanna L.; Southan, Christopher; Buneman, O. Peter; Cidlowski, John A.; Christopoulos, Arthur; Davenport, Anthony P.; Fabbro, Doriano; Spedding, Michael; Striessnig, Jörg; Davies, Jamie A.; Abbracchio, M.-P.; Aldrich, R.; Al-Hosaini, K.; Arumugam, T. V.; Attali, B.; Bäck, M.; Barnes, N. M.; Bathgate, R.; Beart, P. M.; Becirovic, E.; Bettler, B.; Biel, M.; Birdsall, N. J.; Blaho, V.; Boison, D.; Bräuner-Osborne, H.; Bröer, S.; Bryant, C.; Burnstock, G.; Calo, G.; Catterall, W. A.; Ceruti, S.; Chan, S. L.; Chandy, K. G.; Chazot, P.; Chiang, N.; Chun, J. J.; Chung, J.-J.; Clapham, D. E.; Clapp, L.; Connor, M. A.; Cox, H. M.; Davies, P.; Dawson, P. A.; Decaen, P.; Dent, G.; Doherty, P.; Douglas, S. D.; Dubocovich, M. L.; Fong, T. M.; Fowler, C. J.; Frantz, A.; Fuller, P.; Fumagalli, M.; Futerman, A. H.; Gainetdinov, R. R.; Gershengorn, M. A.; Goldin, A.; Goldstein, San; Goudet, C.; Gregory, K.; Grissmer, S.; Gundlach, A. L.; Hagenbuch, B.; Hamann, Jörg; Hammond, J. R.; Hancox, J. C.; Hanson, J.; Hanukoglu, I.; Hay, D. L.; Hobbs, A. J.; Hollenberg, A. N.; Holliday, N. D.; Hoyer, D.; IJzerman, A. P.; Inui, K. I.; Irving, A. J.; Ishii, S.; Jacobson, K. A.; Jan, L. Y.; Jarvis, M. F.; Jensen, R.; Jockers, R.; Kaczmarek, L. K.; Kanai, Y.; Karnik, S.; Kellenberger, S.; Kemp, Stephan; Kennedy, C.; Kerr, I. D.; Kihara, Y.; Kukkonen, J.; Larhammar, D.; Leach, K.; Lecca, D.; Leeman, S.; Leprince, J.; Lolait, S. J.; MacEwan, D.; Maguire, J. J.; Marshall, F.; Mazella, J.; McArdle, C. A.; Michel, M. C.; Miller, L. J.; Mitolo, V.; Mizuno, H.; Monk, P. N.; Mouillac, B.; Murphy, P. M.; Nahon, J.-L.; Nerbonne, J.; Nichols, C. G.; Norel, X.; Offermanns, S.; Palmer, L. G.; Panaro, M. A.; Papapetropoulos, A.; Perez-Reyes, E.; Pertwee, R. G.; Pintor, S.; Pisegna, J. R.; Plant, L. D.; Poyner, D. R.; Prossnitz, E. R.; Pyne, S.; Ramachandran, R.; Ren, D.; Rondard, P.; Ruzza, C.; Sackin, H.; Sanger, G.; Sanguinetti, M. C.; Schild, L.; Schiöth, H.; Schulte, G.; Schulz, S.; Segaloff, D. L.; Serhan, C. N.; Singh, K. D.; Slesinger, P. A.; Snutch, T. P.; Sobey, C. G.; Stewart, G.; Stoddart, L. A.; Summers, R. J.; Szabo, C.; Thwaites, D.; Toll, L.; Trimmer, J. S.; Tucker, S.; Vaudry, H.; Verri, T.; Vilargada, J.-P.; Waldman, S. A.; Ward, D. T.; Waxman, S. G.; Wei, A. D.; Willars, G. B.; Wong, S. S.; Woodruff, T. M.; Wulff, H.; Ye, R. D.; Yung, Y.; Zajac, J.-M.

    2017-01-01

    The Concise Guide to PHARMACOLOGY 2017/18 is the third in this series of biennial publications. This version provides concise overviews of the key properties of nearly 1800 human drug targets with an emphasis on selective pharmacology (where available), plus links to an open access knowledgebase of

  4. Some Pharmacological Studies Of Aqueous Extract Of Leaves Of ...

    African Journals Online (AJOL)

    This work was set out to identify the pharmacological basis for the laxative effect of leaves of Euphorbia heterophylla as well as identify its other pharmacological properties: Material/ Methods: Effect of aqueous extract of the leaves was tested on isolated guinea pig ileum and isolated pregnant rat uterus using organ bath ...

  5. Principles of pharmacology in the eye.

    Science.gov (United States)

    Awwad, Sahar; Mohamed Ahmed, Abeer H A; Sharma, Garima; Heng, Jacob S; Khaw, Peng T; Brocchini, Steve; Lockwood, Alastair

    2017-09-02

    The eye is a highly specialized organ that is subject to a huge range of pathology. Both local and systemic disease may affect different anatomical regions of the eye. The least invasive routes for ocular drug administration are topical (e.g. eye drops) and systemic (e.g. tablets) formulations. Barriers that subserve as protection against pathogen entry also restrict drug permeation. Topically administered drugs often display limited bioavailability due to many physical and biochemical barriers including the pre-corneal tear film, the structure and biophysiological properties of the cornea, the limited volume that can be accommodated by the cul-de-sac, the lacrimal drainage system and reflex tearing. The tissue layers of the cornea and conjunctiva are further key factors that act to restrict drug delivery. Using carriers that enhance viscosity or bind to the ocular surface increases bioavailability. Matching the pH and polarity of drug molecules to the tissue layers allows greater penetration. Drug delivery to the posterior segment is a greater challenge and, currently, the standard route is via intravitreal injection, notwithstanding the risks of endophthalmitis and retinal detachment with frequent injections. Intraocular implants that allow sustained drug release are at different stages of development. Novel exciting therapeutic approaches include methods for promoting transscleral delivery, sustained release devices, nanotechnology and gene therapy. © 2017 The British Pharmacological Society.

  6. Enhanced photocatalytic properties of graphene modified few-layered WSe{sub 2} nanosheets

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Bo; Zheng, Binjie; Wang, Xinqiang; Qi, Fei; He, Jiarui; Zhang, Wanli; Chen, Yuanfu, E-mail: yfchen@uestc.edu.cn

    2017-04-01

    Highlights: • High-quality WSe{sub 2}/RGO composite has been synthesized through a facile one-pot solvothermal reaction. • WSe{sub 2}/RGO composite demonstrates significant enhancement in photocatalytic performance in visible region. • WSe{sub 2}/RGO composite is a promising catalyst for photocatalytic degradation of organic pollutants by solar energy. • Excellent charge separation and electronic transport properties are responsible for the enhancement in photocatalytic performance. - Abstract: Reduced graphene oxide (RGO) modified few-layered WSe{sub 2} nanosheets have been synthesized through a facile one-pot solvothermal reaction. Compared with bare WSe{sub 2} nanosheets with relatively poor photocatalytic activity, WSe{sub 2}/RGO composite demonstrates significant enhancement in photocatalytic degradation of organic dye RhB under visible light irradiation. The k value of WSe{sub 2}/RGO is ∼1.9 times larger than that of bare WSe{sub 2} nanosheets, which is attributed to the excellent charge separation feature and electronic transport ability of graphene nanosheets, leading to highly reduced electron-hole pair recombination of graphene on WSe{sub 2} nanosheets thus strongly enhancing the photocatalytic performance. The WSe{sub 2}/RGO composite is a promising catalyst for photocatalytic degradation of organic pollutants by solar energy.

  7. The magnetic-nanofluid heat pipe with superior thermal properties through magnetic enhancement

    Science.gov (United States)

    Chiang, Yuan-Ching; Chieh, Jen-Jie; Ho, Chia-Che

    2012-06-01

    This study developed a magnetic-nanofluid (MNF) heat pipe (MNFHP) with magnetically enhanced thermal properties. Its main characteristic was additional porous iron nozzle in the evaporator and the condenser to form a unique flowing pattern of MNF slug and vapor, and to magnetically shield the magnet attraction on MNF flowing. The results showed that an optimal thermal conductivity exists in the applied field of 200 Oe. Furthermore, the minor thermal performance of MNF at the condenser limited the thermal conductivity of the entire MNFHP, which was 1.6 times greater than that filled with water for the input power of 60 W. The feasibilities of an MNFHP with the magnetically enhanced heat transfer and the ability of vertical operation were proved for both a promising heat-dissipation device and the energy architecture integrated with an additional energy system.

  8. Enhancement in Mechanical and Shape Memory Properties for Liquid Crystalline Polyurethane Strengthened by Graphene Oxide

    Directory of Open Access Journals (Sweden)

    Yueting Li

    2016-07-01

    Full Text Available Conventional shape memory polymers suffer the drawbacks of low thermal stability, low strength, and low shape recovery speed. In this study, main-chain liquid crystalline polyurethane (LCPU that contains polar groups was synthesized. Graphene oxide (GO/LCPU composite was fabricated using the solution casting method. The tensile strength of GO/LCPU was 1.78 times that of neat LCPU. In addition, shape recovery speed was extensively improved. The average recovery rate of sample with 20 wt % GO loading was 9.2°/s, much faster than that of LCPU of 2.6°/s. The enhancement in mechanical property and shape memory behavior could be attributed to the structure of LCPU and GO, which enhanced the interfacial interactions between GO and LCPU.

  9. Reduced silanized graphene oxide/epoxy-polyurethane composites with enhanced thermal and mechanical properties

    Energy Technology Data Exchange (ETDEWEB)

    Lin, Jing, E-mail: linjin00112043@126.com [School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006 (China); Zhang, Peipei [Worcester Polytechnic Institute, Worcester, MA 01605 (United States); Zheng, Cheng; Wu, Xu; Mao, Taoyan; Zhu, Mingning; Wang, Huaquan; Feng, Danyan; Qian, Shuxuan; Cai, Xianfang [School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006 (China)

    2014-10-15

    Graphical abstract: The synthesis route for EPUAs/R-Si-GEO composites. - Highlights: • Reduced silanized graphene oxide as fillers. • The graphene layers were well distributed in the epoxy-polyurethane composites. • The thermal stabilities of composites were greatly improved by incorporation of the graphene. • Mechanical properties of composites were greatly enhanced by the incorporation of the graphene. - Abstract: This paper describes the synthesis of reduced silanized graphene oxide/epoxy-polyurethane (EPUAs/R-Si-GEO) composites with enhanced thermal and mechanical properties. Graphene oxide (GEO), prepared from natural graphite flakes, was modified with methacryloxypropyltrimethoxysilane to prepare silanized GEO (Si-GEO), and was then reduced by NaHSO{sub 3} to prepare R-Si-GEO (partially reduced Si-GEO). EPAc/R-Si-GEO (R-Si-GEO/epoxy acrylate copolymers) was synthesized via an in situ polymerization of R-Si-GEO and epoxy acrylic monomers. EPUAs/R-Si-GEO was obtained by curing reaction between EPAc/R-Si-GEO and an isocyanate curing agent. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD) were used to characterize the surface and crystal structure of the modified graphene and EPUAs/R-Si-GEO. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to characterize their morphology. Thermal gravimetric analysis (TGA), tensile strength, elongation at break, and cross-linking density measurements showed that the thermal stability and mechanical properties of EPUAs/R-Si-GEO were greatly enhanced by the addition of R-Si-GEO.

  10. Ethnobotanical review and pharmacological properties of selected medicinal plants in Brunei Darussalam: Litsea elliptica, Dillenia suffruticosa, Dillenia excelsa, Aidia racemosa, Vitex pinnata and Senna alata

    OpenAIRE

    May Poh Yik Goh; Aida Maryam Basri; Hartini Yasin; Hussein Taha; Norhayati Ahmad

    2017-01-01

    The aim of the current study is to review the medicinal properties of the plants found in Brunei Darussalam namely Litsea elliptica, Dillenia suffruticosa, Dillenia excelsa, Aidia racemosa, Vitex pinnata and Senna alata. The known phytochemical constituents of these plants and their ability to bring about a range of biological activities are included in this review. These plants have been used traditionally for a multitude of diseases and illnesses. There is a lot of untapped potential in the...

  11. Genus Cistus: a model for exploring labdane-type diterpenes' biosynthesis and a natural source of high value products with biological, aromatic, and pharmacological properties.

    Science.gov (United States)

    Papaefthimiou, Dimitra; Papanikolaou, Antigoni; Falara, Vasiliki; Givanoudi, Stella; Kostas, Stefanos; Kanellis, Angelos K

    2014-01-01

    The family Cistaceae (Angiosperm, Malvales) consists of 8 genera and 180 species, with 5 genera native to the Mediterranean area (Cistus, Fumara, Halimium, Helianthemum, and Tuberaria). Traditionally, a number of Cistus species have been used in Mediterranean folk medicine as herbal tea infusions for healing digestive problems and colds, as extracts for the treatment of diseases, and as fragrances. The resin, ladano, secreted by the glandular trichomes of certain Cistus species contains a number of phytochemicals with antioxidant, antibacterial, antifungal, and anticancer properties. Furthermore, total leaf aqueous extracts possess anti-influenza virus activity. All these properties have been attributed to phytochemicals such as terpenoids, including diterpenes, labdane-type diterpenes and clerodanes, phenylpropanoids, including flavonoids and ellagitannins, several groups of alkaloids and other types of secondary metabolites. In the past 20 years, research on Cistus involved chemical, biological and phylogenetic analyses but recent investigations have involved genomic and molecular approaches. Our lab is exploring the biosynthetic machinery that generates terpenoids and phenylpropanoids, with a goal to harness their numerous properties that have applications in the pharmaceutical, chemical and aromatic industries. This review focuses on the systematics, botanical characteristics, geographic distribution, chemical analyses, biological function and biosynthesis of major compounds, as well as genomic analyses and biotechnological approaches of the main Cistus species found in the Mediterranean basin, namely C. albidus, C. creticus, C. crispus, C. parviflorus, C. monspeliensis, C. populifolius, C. salviifolius, C. ladanifer, C. laurifolius, and C. clusii.

  12. Genus Cistus: a model for exploring labdane-type diterpenes' biosynthesis and a natural source of high value products with biological, aromatic and pharmacological properties

    Directory of Open Access Journals (Sweden)

    Dimitra ePapaefthimiou

    2014-06-01

    Full Text Available The family Cistaceae (Angiosperm, Malvales consists of 8 genera and 180 species, with 5 genera native of the Mediterranean area (Cistus, Fumara, Halimium, Helianthemum and Tuberaria. Traditionally, a number of Cistus specie have been used in Mediterranean folk medicine as herbal tea infusions for healing, digestive problems and colds, as extracts for the treatment of diseases, and as fragrances. The resin, ladano, secreted by the glandular trichomes of certain Cistus species contains a number of phytochemicals with antioxidant, antibacterial, antifungal and anticancer properties. Furthermore, total leaf aqueous extracts possess anti-influenza virus activity. All these properties have been attributed to phytochemicals such as terpenoids, including diterpenes, labdane-type diterpenes and clerodanes, phenylpropanoids, including flavonoids and ellagitannins, several groups of alkaloids and other types of secondary metabolites. In the past 20 years, research on Cistus involved chemical, biological and phylogenetic analysis but recent investigations have involved genomic and molecular approaches. Our lab is exploring the biosynthetic machinery that generates terpenoids and phenylpropanoids, with a goal to harness their numerous properties that have applications in the pharmaceutical, chemical and aromatic industries. This review focuses on the systematics, botanical characteristics, geographic distribution, chemical analyses, biological function and biosynthesis of major compounds, as well as genomic analyses and biotechnological approaches of the main Cistus species found in the Mediterranean basin, namely C. albidus, C. creticus, C. crispus, C. parviflorus, C. monspeliensis, C. populifolius, C. salviifolius, C. ladanifer, C. laurifolius and C. clusii.

  13. Genus Cistus: a model for exploring labdane-type diterpenes' biosynthesis and a natural source of high value products with biological, aromatic and pharmacological properties

    Science.gov (United States)

    Papaefthimiou, Dimitra; Papanikolaou, Antigoni; Falara, Vasiliki; Givanoudi, Stella; Kostas, Stefanos; Kanellis, Angelos

    2014-06-01

    The family Cistaceae (Angiosperm, Malvales) consists of 8 genera and 180 species, with 5 genera native of the Mediterranean area (Cistus, Fumara, Halimium, Helianthemum and Tuberaria). Traditionally, a number of Cistus specie have been used in Mediterranean folk medicine as herbal tea infusions for healing, digestive problems and colds, as extracts for the treatment of diseases, and as fragrances. The resin, ladano, secreted by the glandular trichomes of certain Cistus species contains a number of phytochemicals with antioxidant, antibacterial, antifungal and anticancer properties. Furthermore, total leaf aqueous extracts possess anti-influenza virus activity. All these properties have been attributed to phytochemicals such as terpenoids, including diterpenes, labdane-type diterpenes and clerodanes, phenylpropanoids, including flavonoids and ellagitannins, several groups of alkaloids and other types of secondary metabolites. In the past 20 years, research on Cistus involved chemical, biological and phylogenetic analysis but recent investigations have involved genomic and molecular approaches. Our lab is exploring the biosynthetic machinery that generates terpenoids and phenylpropanoids, with a goal to harness their numerous properties that have applications in the pharmaceutical, chemical and aromatic industries. This review focuses on the systematics, botanical characteristics, geographic distribution, chemical analyses, biological function and biosynthesis of major compounds, as well as genomic analyses and biotechnological approaches of the main Cistus species found in the Mediterranean basin, namely C. albidus, C. creticus, C. crispus, C. parviflorus, C. monspeliensis, C. populifolius, C. salviifolius, C. ladanifer, C. laurifolius and C. clusii.

  14. Pharmacological management of obesity.

    Science.gov (United States)

    Velazquez, Amanda; Apovian, Caroline M

    2017-04-28

    Current management of obesity includes three main arms: behavioral modification, pharmacologic therapy, and bariatric surgery. Decades prior, the only pharmacological agents available to treat obesity were approved only for short-term use (≤ 12 weeks) by the Food and Drug Administration (FDA). However, in the last several years, the FDA has approved several medications for longer term treatment of obesity. This highlights the important progression that we, as a society, better appreciate now the chronicity and complexity of obesity as a disease. Also, availability of more medication options gives healthcare providers more possibilities to consider in the management of obesity. Medications for obesity can be simply categorized as FDA approved short-term use (diethylproprion, phendimetrazine, benzphetamine, and phentermine) and long-term use (orlistat, phentermine/topiramate ER, lorcaserin, naltrexone/bupropion ER and liraglutide). Additionally, type 2 diabetes (T2DM) is commonly seen in patients with obesity and necessitates consideration of pharmacological options that do not hinder patients' weight loss. Finally, weight-centric prescribing is also an important component to pharmacological management of obesity. It warrants that healthcare providers thoroughly review their patients' medication lists to determine if any of these agents could be contributing to weight gain.

  15. Developmental paediatric anaesthetic pharmacology

    DEFF Research Database (Denmark)

    Hansen, Tom Giedsing

    2015-01-01

    Safe and effective drug therapy in neonates, infants and children require detailed knowledge about the ontogeny of drug disposition and action as well how these interact with genetics and co-morbidity of children. Recent advances in developmental pharmacology in children follow the increased...

  16. CLINICAL PHARMACOLOGY OF DIURETICS

    Directory of Open Access Journals (Sweden)

    I. V. Soldatenko

    2014-06-01

    Full Text Available Clinical pharmacology of diuretics in the international system of ATC (anatomic-therapeutic-chemical is presented. Classification of this group by the action mechanism and caused effects is provided. Pharmacokinetics and pharmacodynamics features, indications and principles of diuretics usage in clinics are considered. Contraindications, side effects and interaction with other drugs of this group are discussed in detail.

  17. Photocured epoxy/graphene nanocomposites with enhanced water vapor barrier properties

    Energy Technology Data Exchange (ETDEWEB)

    Periolatto, M.; Spena, P. Russo [Faculty of Science and Technology, Free University of Bozen-Bolzano, Piazza Università 5, Bolzano (Italy); Sangermano, M. [Dipartimento di Scienza Applicata e Tecnologia, Politecnico di Torino, C.so Duca degli Abruzzi 24, Torino (Italy)

    2016-05-18

    A transparent, water vapor barrier film made of an epoxy resin and graphene oxide (GO) was synthesized by photopolymerization process. The epoxy/GO film with just 0.05 wt% GO gives a 93% WVTR reduction with respect to the pristine polymer, reaching barrier properties better than other polymer composites containing higher amounts of graphene. The excellent water vapor barrier is attributed to the good dispersion of GO in the polymer matrix. Moreover, GO significantly enhances the toughness and the damping capacity of the epoxy resins. The hybrid film can have potential applications in anticorrosive coatings, electronic devices, pharmaceuticals and food packaging.

  18. Thermophysical Properties of Nanoparticle-Enhanced Ionic Liquids (NEILs) Heat-Transfer Fluids

    Energy Technology Data Exchange (ETDEWEB)

    Fox, Elise B.; Visser, Ann E.; Bridges, Nicholas J.; Amoroso, Jake W.

    2013-06-20

    An experimental investigation was completed on nanoparticle enhanced ionic liquid heat transfer fluids as an alternative to conventional organic based heat transfer fluids (HTFs). These nanoparticle-based HTFs have the potential to deliver higher thermal conductivity than the base fluid without a significant increase in viscosity at elevated temperatures. The effect of nanoparticle morphology and chemistry on thermophysical properties was examined. Whisker shaped nanomaterials were found to have the largest thermal conductivity temperature dependence and were also less likely to agglomerate in the base fluid than spherical shaped nanomaterials.

  19. Aqueous Phase Synthesis and Enhanced Field Emission Properties of ZnO-Sulfide Heterojunction Nanowires

    OpenAIRE

    Guojing Wang; Zhengcao Li; Mingyang Li; Chienhua Chen; Shasha Lv; Jiecui Liao

    2016-01-01

    ZnO-CdS, ZnO-ZnS, and ZnO-Ag2S core-shell heterojunction structures were fabricated using low-temperature, facile and simple aqueous solution approaches. The polycrystalline sulfide shells effectively enhance the field emission (FE) properties of ZnO nanowires arrays (NWAs). This results from the formation of the staggered gap heterointerface (ZnO-sulfide) which could lead to an energy well at the interfaces. Hence, electrons can be collected when an electric field is applied. It is observed ...

  20. Ginsenoside Re: pharmacological effects on cardiovascular system.

    Science.gov (United States)

    Peng, Lu; Sun, Shi; Xie, Lai-Hua; Wicks, Sheila M; Xie, Jing-Tian

    2012-08-01

    Ginsenosides are the bioactive constituents of ginseng, a key herb in traditional Chinese medicine. As a single component of ginseng, ginsenoside Re (G-Re) belongs to the panaxatriol group. Many reports demonstrated that G-Re possesses the multifaceted beneficial pharmacological effects on cardiovascular system. G-Re has negative effect on cardiac contractility and autorhythmicity. It causes alternations in cardiac electrophysiological properties, which may account for its antiarrhythmic effect. In addition, G-Re also exerts antiischemic effect and induces angiogenic regeneration. In this review, we first outline the chemistry and the pharmacological effects of G-Re on the cardiovascular system. © 2011 Blackwell Publishing Ltd.

  1. Rhein: A Review of Pharmacological Activities

    Directory of Open Access Journals (Sweden)

    Yan-Xi Zhou

    2015-01-01

    Full Text Available Rhein (4, 5-dihydroxyanthraquinone-2-carboxylic acid is a lipophilic anthraquinone extensively found in medicinal herbs, such as Rheum palmatum L., Cassia tora L., Polygonum multiflorum Thunb., and Aloe barbadensis Miller, which have been used medicinally in China for more than 1,000 years. Its biological activities related to human health are being explored actively. Emerging evidence suggests that rhein has many pharmacological effects, including hepatoprotective, nephroprotective, anti-inflammatory, antioxidant, anticancer, and antimicrobial activities. The present review provides a comprehensive summary and analysis of the pharmacological properties of rhein, supporting the potential uses of rhein as a medicinal agent.

  2. Enhancing the Mechanical Properties of Electrospun Nanofiber Mats through Controllable Welding at the Cross Points.

    Science.gov (United States)

    Li, Haoxuan; Zhu, Chunlei; Xue, Jiajia; Ke, Qinfei; Xia, Younan

    2017-05-01

    This communication describes a simple and effective method for welding electrospun nanofibers at the cross points to enhance the mechanical properties of their nonwoven mats. The welding is achieved by placing a nonwoven mat of the nanofibers in a capped vial with the vapor of a proper solvent. For polycaprolactone (PCL) nanofibers, the solvent is dichloromethane (DCM). The welding can be managed in a controllable fashion by simply varying the partial pressure of DCM and/or the exposure time. Relative to the pristine nanofiber mat, the mechanical strength of the welded PCL nanofiber mat can be increased by as much as 200%. Meanwhile, such a treatment does not cause any major structural changes, including morphology, fiber diameter, and pore size. This study provides a generic method for improving the mechanical properties of nonwoven nanofiber mats, holding great potential in various applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Enhanced Magnetic Properties of Graphene Coated with Fe2O3 Nanoparticles.

    Science.gov (United States)

    Neupane, Suman; Hong, Haiping; Giri, Lily; Karna, Shashi P; Seifu, Dereje

    2015-09-01

    Graphene, with its unique 2D nanostructure and excellent electrical, thermal, and mechanical properties, is considered an alternative to carbon nanotubes in nanocomposites. In this study, we present a one step approach for the deposition of iron oxide (Fe2O3) nanoparticles onto graphene sheets through solution mixture. The morphology, crystallinity, and magnetic properties of as-synthesized composites were investigated. It was shown that highly crystalline Fe2O3 nanoparticles were densely and uniformly coated on graphene surface. Magnetic measurements reveal that, as compared to weak diamagnetism of pristine graphene, graphene-Fe2O3 nanocomposites display ferromagnetic behavior with coercivity of 101 Oe, saturation magnetization of 12.6 emu g(-1), and remanent magnetization of 3.13 emu g(-1) at room temperature. The enhanced magnetic performance was attributed to the homogeneous dispersion of Fe2O3 nanoparticles in graphene matrix and such nanocomposites are promising materials for applications in magnetic media and energy storage.

  4. Enhanced Mechanical Properties of Nanoparticle Networks Cross-Linked by Biomimetic Catch Bonds

    Science.gov (United States)

    Mbanga, Badel L.; Iyer, Balaji V. S.; Yashin, Victor V.; Balazs, Anna C.

    2015-03-01

    The tunable behavior of cross-linked networks of Polymer-Grafted Nanoparticles (PGNs) makes them excellent candidates for designing novel materials with enhanced mechanical properties. The building block of a PGN network is a nanoparticle with grafted polymer chains whose free ends' reactive groups can form bonds with the end chains on the nearby particles. We use computer modeling to study the tensile behavior of 3D samples, in which some fraction of cross-links is formed through the biomimetic ``catch'' bonds. In contrast to conventional ``slip'' bonds, the catch bonds might become stronger under an applied force due to transitions between two conformational states. The mechanical properties of the PGN networks are shown to exhibit a drastic improvement upon introduction of the catch bonds into the network. We discuss how ductility, toughness, and rate of strain recovery of the network depend on the catch bond content.

  5. Enhancing Microstructure and Mechanical Properties of AZ31-MWCNT Nanocomposites through Mechanical Alloying

    Directory of Open Access Journals (Sweden)

    J. Jayakumar

    2013-01-01

    Full Text Available Multiwall carbon nanotubes (MWCNTs reinforced Mg alloy AZ31 nanocomposites were fabricated by mechanical alloying and powder metallurgy technique. The reinforcement material MWCNTs were blended in three weight fractions (0.33%, 0.66%, and 1% with the matrix material AZ31 (Al-3%, zinc-1% rest Mg and blended through mechanical alloying using a high energy planetary ball mill. Specimens of monolithic AZ31 and AZ31-MWCNT composites were fabricated through powder metallurgy technique. The microstructure, density, hardness, porosity, ductility, and tensile properties of monolithic AZ31 and AZ31-MWCNT nano composites were characterized and compared. The characterization reveals significant reduction in CNT (carbon nanoTube agglomeration and enhancement in microstructure and mechanical properties due to mechanical alloying through ball milling.

  6. Hybrid Organic/Inorganic Perovskite–Polymer Nanocomposites: Toward the Enhancement of Structural and Electrical Properties

    KAUST Repository

    Privitera, Alberto

    2017-11-30

    Hybrid organic/inorganic perovskite nanoparticles (NPs) have garnered remarkable research attention because of their promising photophysical properties. New and interesting properties emerge after combining perovskite NPs with semiconducting materials. Here, we report the synthesis and investigation of a composite material obtained by mixing CH3NH3PbBr3 nanocrystals with the semiconducting polymer poly(3-hexylthiophene) (P3HT). By the combination of structural techniques and optical and magnetic spectroscopies we observed multiple effects of the perovskite NPs on the P3HT: (i) an enlargement of P3HT crystalline domains, (ii) a strong p-doping of the P3HT, and (iii) an enhancement of interchain order typical of H-aggregates. These observations open a new avenue toward innovative perovskite NP-based applications.

  7. Enhancement of mechanical properties of porous aluminum by silica sand particles

    Science.gov (United States)

    Khamsuk, S.; Joosawat, A.; Panomtang, N.; Wongtimnoi, K.

    2017-09-01

    Porous aluminum was fabricated using space holder process. The spherical carbamide powder and silica sand were used as space holder and reinforcement materials, respectively. Aluminum powders were mixed with five different silica sand contents and were then mixed with 10 wt.% carbamide powder. The mixed powders were cold compression at 400 MPa and sintered at 550 °C for 5 hours. Microstructure of specimen was characterized by scanning electron microscope. Hardness and compressive strength were also investigated in this study. It was found that microstructure and mechanical properties of porous aluminum strongly depended on silica sand contents. From SEM observation, it is clearly seen that addition of silica sand led to increasing pore in the porous aluminum. Mechanical properties of porous aluminum can be enhanced by silica sand particle reinforced.

  8. Alkaloids from piper: a review of its phytochemistry and pharmacology.

    Science.gov (United States)

    Gutierrez, Rosa Martha Perez; Gonzalez, Adriana Maria Neira; Hoyo-Vadillo, Carlos

    2013-02-01

    Piper has been used for long timelike condiment and food, but also in traditional medicine around of the world. This work resumes the available and up to date work done on members of the Piperaceae family and their uses for therapeutic purposes. Information on Piper genus was gathered via internet using scientific databases such as Scirus, Google Scholar, CAB-abstracts, MedlinePlus, Pubmed, SciFinder, Scopus and Web of Science. The largeleafed perennial plant Piper is used for its spicy aromatic scent and flavor. It has an important presence in the cuisine of different cultures. Another quality of these plants is their known medicinal properties. It has been used as emollient, antirheumatic, diuretic, stimulant, abortifacient, anti-inflammatory, antibacterial, antifungal and antidermatophytic. A survey of the literature shows that the genus Piper is mainly known for its alkaloids with cytotoxic, chemopreventive, antimetastatic and antitumor properties in several types of cancer. Studies of its alkaloids highlight the existence of various potential leads to develop new anti-cancer agents. Modern pharmacology studies have demonstrated that its crude extracts and active compounds possess wide pharmacological activities, especially asantioxidant, anti-depressive, hepatoprotective, antimicrobial, anti-obesity, neuropharmacological, to treat cognitive disorders, anti-hyperlipidemic, anti-feedant, cardioactive, immuno-enhancing, and anti-inflamatory. All this evidence supporting its traditional uses. This review summarizes the up-to-date and comprehensive information concerning the botany, traditional use, phytochemistry and pharmacology of Piper together with its toxicology, and discusses the possible trend and scope for further research on Piper in the future.

  9. Selection of the intrinsic polarization properties of animal optical materials creates enhanced structural reflectivity and camouflage.

    Science.gov (United States)

    Feller, Kathryn D; Jordan, Thomas M; Wilby, David; Roberts, Nicholas W

    2017-07-05

    Many animals use structural coloration to create bright and conspicuous visual signals. Selection of the size and shape of the optical structures animals use defines both the colour and intensity of the light reflected. The material used to create these reflectors is also important; however, animals are restricted to a limited number of materials: commonly chitin, guanine and the protein, reflectin. In this work we highlight that a particular set of material properties can also be under selection in order to increase the optical functionality of structural reflectors. Specifically, polarization properties, such as birefringence (the difference between the refractive indices of a material) and chirality (which relates to molecular asymmetry) are both under selection to create enhanced structural reflectivity. We demonstrate that the structural coloration of the gold beetle Chrysina resplendens and silvery reflective sides of the Atlantic herring, Clupea harengus are two examples of this phenomenon. Importantly, these polarization properties are not selected to control the polarization of the reflected light as a source of visual information per se. Instead, by creating higher levels of reflectivity than are otherwise possible, such internal polarization properties improve intensity-matching camouflage.This article is part of the themed issue 'Animal coloration: production, perception, function and application'. © 2017 The Authors.

  10. Enhanced leavening properties of baker's yeast by reducing sucrase activity in sweet dough.

    Science.gov (United States)

    Zhang, Cui-Ying; Lin, Xue; Feng, Bing; Liu, Xiao-Er; Bai, Xiao-Wen; Xu, Jia; Pi, Li; Xiao, Dong-Guang

    2016-07-01

    Leavening ability in sweet dough is required for the commercial applications of baker's yeast. This property depends on many factors, such as glycolytic activity, sucrase activity, and osmotolerance. This study explored the importance of sucrase level on the leavening ability of baker's yeast in sweet dough. Furthermore, the baker's yeast strains with varying sucrase activities were constructed by deleting SUC2, which encodes sucrase or replacing the SUC2 promoter with the VPS8/TEF1 promoter. The results verify that the sucrase activity negatively affects the leavening ability of baker's yeast strains under high-sucrose conditions. Based on a certain level of osmotolerance, sucrase level plays a significant role in the fermentation performance of baker's yeast, and appropriate sucrase activity is an important determinant for the leavening property of baker's yeast in sweet dough. Therefore, modification on sucrase activity is an effective method for improving the leavening properties of baker's yeast in sweet dough. This finding provides guidance for the breeding of industrial baker's yeast strains for sweet dough leavening. The transformants BS1 with deleted SUC2 genetic background provided decreased sucrase activity (a decrease of 39.3 %) and exhibited enhanced leavening property (an increase of 12.4 %). Such a strain could be useful for industrial applications.

  11. Enhanced catalytic properties of mesoporous mordenite for benzylation of benzene with benzyl alcohol

    Science.gov (United States)

    Saxena, Sandeep K.; Viswanadham, Nagabhatla

    2017-01-01

    Zeolite mordenite has been treated with nitric acid at different severities so as to facilitate the framework dealumination and optimization of the textural properties such as acidity and porosity. The samples obtained have been characterized by X-ray diffraction, FTIR, SEM, TEM, surface area, porosity by N2 adsorption and ammonia TPD. The resultant samples have been evaluated towards the bulky alkylation reaction of benzylation of benzene with benzyl alcohol. The studies indicated the improvement in the textural properties such as surface area, pore volume and acidity of the samples after the acid treatment. While, the phenomenon of enhancement in properties was exhibited by all the acid treated mordenite samples, the highest improvement in properties was observed at a particular condition of acid treatment (SM-2 sample). This particular sample also exhibited highest acidity and the presence of ∼10 nm size pores that resulted in the effective catalytic activity towards the bulky alkylation reaction of benzene with benzyl alcohol to produce high yields of di-phenyl methane.

  12. Botulinum Neurotoxins: Biology, Pharmacology, and Toxicology

    Science.gov (United States)

    Pirazzini, Marco; Rossetto, Ornella; Eleopra, Roberto

    2017-01-01

    The study of botulinum neurotoxins (BoNT) is rapidly progressing in many aspects. Novel BoNTs are being discovered owing to next generation sequencing, but their biologic and pharmacological properties remain largely unknown. The molecular structure of the large protein complexes that the toxin forms with accessory proteins, which are included in some BoNT type A1 and B1 pharmacological preparations, have been determined. By far the largest effort has been dedicated to the testing and validation of BoNTs as therapeutic agents in an ever increasing number of applications, including pain therapy. BoNT type A1 has been also exploited in a variety of cosmetic treatments, alone or in combination with other agents, and this specific market has reached the size of the one dedicated to the treatment of medical syndromes. The pharmacological properties and mode of action of BoNTs have shed light on general principles of neuronal transport and protein-protein interactions and are stimulating basic science studies. Moreover, the wide array of BoNTs discovered and to be discovered and the production of recombinant BoNTs endowed with specific properties suggest novel uses in therapeutics with increasing disease/symptom specifity. These recent developments are reviewed here to provide an updated picture of the biologic mechanism of action of BoNTs, of their increasing use in pharmacology and in cosmetics, and of their toxicology. PMID:28356439

  13. Ethnobotanical review and pharmacological properties of selected medicinal plants in Brunei Darussalam: Litsea elliptica, Dillenia suffruticosa, Dillenia excelsa, Aidia racemosa, Vitex pinnata and Senna alata

    Directory of Open Access Journals (Sweden)

    May Poh Yik Goh

    2017-02-01

    Full Text Available The aim of the current study is to review the medicinal properties of the plants found in Brunei Darussalam namely Litsea elliptica, Dillenia suffruticosa, Dillenia excelsa, Aidia racemosa, Vitex pinnata and Senna alata. The known phytochemical constituents of these plants and their ability to bring about a range of biological activities are included in this review. These plants have been used traditionally for a multitude of diseases and illnesses. There is a lot of untapped potential in these medicinal plants which could cure multiple diseases.

  14. Synthesis, brain uptake, and pharmacological properties of a glyceryl lipid containing GABA and the GABA-T inhibitor gamma-vinyl-GABA.

    Science.gov (United States)

    Jacob, J N; Hesse, G W; Shashoua, V E

    1990-02-01

    1-O-Linolenoyl-2-O-(4-aminobutyryl)-3-O-(4-vinyl-4-aminobutyryl)glycerol (LGV) was synthesized as an example of a prodrug which readily penetrates the blood-brain barrier (brain penetration index 97% +/- 15%) and releases two active substances in the central nervous system (CNS): GABA (4-aminobutanoic acid) and the GABA transaminase inhibitor (GABA-T) of GABA breakdown. In vitro studies showed that the compound can inhibit GABA-T after hydrolysis by CNS esterases and that it enhanced GABAergic inhibition when applied to rat hippocampus slices. In vivo studies indicate that LGV depresses the spontaneous locomotor activity of mice. Its activity on a molar basis was some 300 times greater than that of gamma-vinyl-GABA.

  15. Enhanced antimicrobial properties, cytocompatibility, and corrosion resistance of plasma-modified biodegradable magnesium alloys.

    Science.gov (United States)

    Zhao, Ying; Jamesh, Mohammed Ibrahim; Li, Wing Kan; Wu, Guosong; Wang, Chenxi; Zheng, Yufeng; Yeung, Kelvin W K; Chu, Paul K

    2014-01-01

    Magnesium alloys are potential biodegradable materials and have received increasing attention due to their outstanding biological performance and mechanical properties. However, rapid degradation in the physiological environment and potential toxicity limit clinical applications. Recently, special magnesium-calcium (Mg-Ca) and magnesium-strontium (Mg-Sr) alloys with biocompatible chemical compositions have been reported, but the rapid degradation still does not meet clinical requirements. In order to improve the corrosion resistance, a rough, hydrophobic and ZrO(2)-containing surface film is fabricated on Mg-Ca and Mg-Sr alloys by dual zirconium and oxygen ion implantation. Weight loss measurements and electrochemical corrosion tests show that the corrosion rate of the Mg-Ca and Mg-Sr alloys is reduced appreciably after surface treatment. A systematic investigation of the in vitro cellular response and antibacterial capability of the modified binary magnesium alloys is performed. The amounts of adherent bacteria on the Zr-O-implanted and Zr-implanted samples diminish remarkably compared to the unimplanted control. In addition, significantly enhanced cell adhesion and proliferation are observed from the Zr-O-implanted sample. The results suggest that dual zirconium and oxygen ion implantation, which effectively enhances the corrosion resistance, in vitro biocompatibility and antimicrobial properties of Mg-Ca and Mg-Sr alloys, provides a simple and practical means to expedite clinical acceptance of biodegradable magnesium alloys. Copyright © 2013 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  16. Hollow metal nanostructures for enhanced plasmonics: synthesis, local plasmonic properties and applications

    Science.gov (United States)

    Genç, Aziz; Patarroyo, Javier; Sancho-Parramon, Jordi; Bastús, Neus G.; Puntes, Victor; Arbiol, Jordi

    2017-01-01

    Metallic nanostructures have received great attention due to their ability to generate surface plasmon resonances, which are collective oscillations of conduction electrons of a material excited by an electromagnetic wave. Plasmonic metal nanostructures are able to localize and manipulate the light at the nanoscale and, therefore, are attractive building blocks for various emerging applications. In particular, hollow nanostructures are promising plasmonic materials as cavities are known to have better plasmonic properties than their solid counterparts thanks to the plasmon hybridization mechanism. The hybridization of the plasmons results in the enhancement of the plasmon fields along with more homogeneous distribution as well as the reduction of localized surface plasmon resonance (LSPR) quenching due to absorption. In this review, we summarize the efforts on the synthesis of hollow metal nanostructures with an emphasis on the galvanic replacement reaction. In the second part of this review, we discuss the advancements on the characterization of plasmonic properties of hollow nanostructures, covering the single nanoparticle experiments, nanoscale characterization via electron energy-loss spectroscopy and modeling and simulation studies. Examples of the applications, i.e. sensing, surface enhanced Raman spectroscopy, photothermal ablation therapy of cancer, drug delivery or catalysis among others, where hollow nanostructures perform better than their solid counterparts, are also evaluated.

  17. Enhanced functional connectivity properties of human brains during in-situ nature experience

    Directory of Open Access Journals (Sweden)

    Zheng Chen

    2016-07-01

    Full Text Available In this study, we investigated the impacts of in-situ nature and urban exposure on human brain activities and their dynamics. We randomly assigned 32 healthy right-handed college students (mean age = 20.6 years, SD = 1.6; 16 males to a 20 min in-situ sitting exposure in either a nature (n = 16 or urban environment (n = 16 and measured their Electroencephalography (EEG signals. Analyses revealed that a brief in-situ restorative nature experience may induce more efficient and stronger brain connectivity with enhanced small-world properties compared with a stressful urban experience. The enhanced small-world properties were found to be correlated with “coherent” experience measured by Perceived Restorativeness Scale (PRS. Exposure to nature also induces stronger long-term correlated activity across different brain regions with a right lateralization. These findings may advance our understanding of the functional activities during in-situ environmental exposures and imply that a nature or nature-like environment may potentially benefit cognitive processes and mental well-being.

  18. Enhancing the Electrocatalytic Property of Hollow Structured Platinum Nanoparticles for Methanol Oxidation Through A Hybrid Construction

    Science.gov (United States)

    Feng, Yan; Liu, Hui; Wang, Pengfei; Ye, Feng; Tan, Qiangqiang; Yang, Jun

    2014-08-01

    The integration of different components into a hybrid nanosystem for the utilization of the synergistic effects is an effective way to design the electrocatalysts. Herein, we demonstrate a hybrid strategy to enhance the electrocatalytic property of hollow structured Pt nanoparticles for methanol oxidation reaction. This strategy begins with the preparation of bimetallic Ag-Pt nanoparticles with a core-shell construction. Element sulfur is then added to transform the core-shell Ag-Pt nanostructures into hybrid nanodimers consisting of Ag2S nanocrystals and remaining Pt domains with intact hollow interiors (Ag2S-hPt). Finally, Au is deposited at the surface of the Ag2S domain in each hetero-dimer, resulting in the formation of ternary Ag2S-Au-hPt nanocomposites with solid-state interfaces. The ternary nanocomposites exhibit enhanced electrocatalytic property toward methanol oxidation due to the strong electronic coupling between Pt and other domains in the hybrid particles. The concept might be used toward the design and synthesis of other hetero-nanostructures with technological importance.

  19. Synergistic effect of Al and Gd on enhancement of mechanical properties of magnesium alloys

    Directory of Open Access Journals (Sweden)

    Bita Pourbahari

    2017-04-01

    Full Text Available The effect of Gd/Al ratio on the properties of as-cast Mg-Gd-Al-Zn alloys was investigated by changing the chemical composition from that of AZ61 to GZ61. At the ratio of 1, the Al2Gd phase becomes predominant and Mg17Al12 is hardly seen in the microstructure. As a potent inoculant, the Al2Gd phase resulted in intense grain refinement and enhancement of strength, ductility and toughness. For instance, the tensile strength and elongation to failure of Mg-3Gd-3Al-1Zn alloy were enhanced by ~4% and 180% compared with those of AZ61 alloy, respectively. However, at high Gd/Al ratios, the Al2Gd phase was replaced by (Mg,Al3Gd and Mg5Gd phases and very large grain sizes were achieved, which led to poor tensile properties and the appearance of cleavage facets on the fracture surfaces. Therefore, it can be deduced that the presence of Gd and Al, in appropriate amounts to reach Gd/Al ratio of ~ 1, is required for the achievement of grain refinement, good ductility, high strength, and the appearance of ductile fracture surfaces in the Mg-Gd-Al-Zn system. Conclusively, the Mg-Gd-Al-Zn alloys can be considered as a new class of structural magnesium alloy and it is superior to both AZ (Mg-Al-Zn and GZ (Mg-Gd-Zn series of alloys.

  20. Enhanced thermoelectric properties of penta-graphene by strain effects process

    Science.gov (United States)

    Chen, Chun-Ping; Liu, Chang; Liu, Lin-Lin; Zhao, Lu-Si; Wang, Xiao-Chun

    2017-10-01

    Using the Boltzmann theory and first-principles electronic structure calculations, we investigated the thermal transport of penta-graphene (PG) without and with biaxial tensile strain effects. The results show that PG has desirable features of good thermoelectric. We predict that the carrier relaxation time of hole is longer than that of electron, implying better thermoelectric performance of p-type PG. The Seebeck coefficient of penta-graphene is 36 times as large as graphene, which is attributed to the existence of bandgap in the PG. In addition, the thermoelectric figure of merit (ZT) of PG is obtained, with optimized value (about 0.053) at room temperature, which is 5.9 times much higher than that of graphene. Moreover, we show that tensile strain effects on the thermoelectric properties of PG. It is found that tensile strain can induce significantly enhanced n- and p-type power factors. Extremely prominent, at room temperature, the ZT of p-type PG at the strain of 11% is 0.481, which is 9.1 times higher than that of unstrained one. The calculated results show that tensile strain is indeed a very effective strategy to achieve enhanced thermoelectric properties.

  1. Hollow metal nanostructures for enhanced plasmonics: synthesis, local plasmonic properties and applications

    Directory of Open Access Journals (Sweden)

    Genç Aziz

    2016-09-01

    Full Text Available Metallic nanostructures have received great attention due to their ability to generate surface plasmon resonances, which are collective oscillations of conduction electrons of a material excited by an electromagnetic wave. Plasmonic metal nanostructures are able to localize and manipulate the light at the nanoscale and, therefore, are attractive building blocks for various emerging applications. In particular, hollow nanostructures are promising plasmonic materials as cavities are known to have better plasmonic properties than their solid counterparts thanks to the plasmon hybridization mechanism. The hybridization of the plasmons results in the enhancement of the plasmon fields along with more homogeneous distribution as well as the reduction of localized surface plasmon resonance (LSPR quenching due to absorption. In this review, we summarize the efforts on the synthesis of hollow metal nanostructures with an emphasis on the galvanic replacement reaction. In the second part of this review, we discuss the advancements on the characterization of plasmonic properties of hollow nanostructures, covering the single nanoparticle experiments, nanoscale characterization via electron energy-loss spectroscopy and modeling and simulation studies. Examples of the applications, i.e. sensing, surface enhanced Raman spectroscopy, photothermal ablation therapy of cancer, drug delivery or catalysis among others, where hollow nanostructures perform better than their solid counterparts, are also evaluated.

  2. Diatomite as a novel composite ingredient for chitosan film with enhanced physicochemical properties.

    Science.gov (United States)

    Akyuz, Lalehan; Kaya, Murat; Koc, Behlul; Mujtaba, Muhammad; Ilk, Sedef; Labidi, Jalel; Salaberria, Asier M; Cakmak, Yavuz Selim; Yildiz, Aysegul

    2017-12-01

    Practical applications of biopolymers in different industries are gaining considerable increase day by day. But still, these biopolymers lack important properties in order to meet the industrial demands. In the same regard, in the current study, chitosan composite films are produced by incorporating diatomite soil at two different concentrations. In order to obtain a homogeneous film, glutaraldehyde was supplemented to chitosan solution as a cross-linker. Compositing diatomaceous earth to chitosan film resulted in improvement of various important physicochemical properties compared to control such as; enhanced film wettability, increase elongation at break and improved thermal stability (264-277°C). The microstructure of the film was observed to haveconsisted of homogeneously distributed blister-shaped structures arised due to the incorporation of diatomite. The incorporation of diatomite did not influence the overall antioxidant activity of the composite films, which can be ascribe to the difficulty radicals formation. Chitosan film incorporated with increasing fraction of diatomite revealed a notable enhancement in the antimicrobial activity. Additionally with the present study, for the first time possible interactions between chitosan/diatomite were determined via quantum chemical calculations. Current study will be helpful in giving a new biotechnological perspective to diatom in terms of its successful application in hydrophobic composite film production. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Hard magnetic property enhancement of Co{sub 7}Hf-based ribbons by boron doping

    Energy Technology Data Exchange (ETDEWEB)

    Chang, H. W. [Department of Applied Physics, Tunghai University, Taichung 407, Taiwan (China); Liao, M. C.; Shih, C. W.; Chang, W. C., E-mail: phywcc@ccu.edu.tw [Department of Physics, National Chung Cheng University, Chia-Yi 621, Taiwan (China); Yang, C. C. [Department of Physics, Chung-Yuan Christian University, Chungli 320, Taiwan (China); Hsiao, C. H.; Ouyang, H. [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 300, Taiwan (China)

    2014-11-10

    Hard magnetic property enhancement of melt spun Co{sub 88}Hf{sub 12} ribbons by boron doping is demonstrated. B-doping could not only remarkably enhance the magnetic properties from energy product ((BH){sub max}) of 2.6 MGOe and intrinsic coercivity ({sub i}H{sub c}) of 1.5 kOe for B-free Co{sub 88}Hf{sub 12} ribbons to (BH){sub max} = 7.7 MGOe and {sub i}H{sub c} = 3.1 kOe for Co{sub 85}Hf{sub 12}B{sub 3} ribbons but also improve the Curie temperature (T{sub C}) of 7:1 phase. The (BH){sub max} value achieved in Co{sub 85}Hf{sub 12}B{sub 3} ribbons is the highest in Co-Hf alloy ribbons ever reported, which is about 15% higher than that of Co{sub 11}Hf{sub 2}B ribbons spun at 16 m/s [M. A. McGuire, O. Rios, N. J. Ghimire, and M. Koehler, Appl. Phys. Lett. 101, 202401 (2012)]. The structural analysis confirms that B enters the orthorhombic Co{sub 7}Hf (7:1) crystal structure as interstitial atoms, forming Co{sub 7}HfB{sub x}, in the as-spun state. Yet B may diffuse out from the 7:1 phase after post-annealing, leading to the reduction of Curie temperature and the magnetic properties. The uniformly refined microstructure with B-doping results in high remanence (B{sub r}) and improves the squareness of demagnetization curve. The formation of interstitial-atom-modified Co{sub 7}HfB{sub x} phase and the microstructure refinement are the main reasons to give rise to the enhancement of hard magnetic properties in the B-containing Co{sub 7}Hf-based ribbons.

  4. Self-assembled supramolecular polymers with tailorable properties that enhance cell attachment and proliferation.

    Science.gov (United States)

    Cheng, Chih-Chia; Lee, Duu-Jong; Chen, Jem-Kun

    2017-03-01

    Self-assembled supramolecular scaffolds, a combination of noncovalent interactions within a biocompatible polymer substrate, can be used for efficient construction of highly-controlled self-organizing hierarchical structures; these newly-developed biomaterials exhibit excellent mechanical properties, tunable surface hydrophilicity, low cytotoxicity and high biodegradability, making them highly attractive for tissue engineering and regenerative medicine applications. Herein, we demonstrate a novel supramolecular poly(ε-caprolactone) (PCL) containing self-complementary sextuple hydrogen-bonded uracil-diamidopyridine (U-DPy) moieties, which undergoes spontaneous self-assembly to form supramolecular polymer networks. Inclusion of various U-DPy contents enhanced the mechanical strength and viscosities of the resulting materials by up to two orders of magnitude compared to control PCL. Surface wettability and morphological studies confirmed physically-crosslinked films can be readily tailored to provide the desired surface properties. Cell viability assays indicated the excellent in vitro biocompatibility of U-DPy-functionalized substrates and indicate the potential of these materials for various biomedical applications. More importantly, mouse fibroblast NIH/3T3 cells cultured on these substrates displayed a more elongated cell morphology and had substantially higher cell densities than cells seeded on control PCL substrate, which indicates that introduction of U-DPy moieties into polymer matrixes could be used to create tissue culture surfaces that enhance cell attachment and proliferation. This new system is suggested as a potential route towards the practical realization of next-generation tissue-engineering scaffolds. In this study, we report a significant breakthrough in development of self-assembled supramolecular polymers to form well-defined scaffolds through self-complementary hydrogen-bonding interactions. These newly developed materials exhibited extremely

  5. Evaluation of the pharmacological properties of salicylic acid-derivative organoselenium: 2-hydroxy-5-selenocyanatobenzoic acid as an anti-inflammatory and antinociceptive compound.

    Science.gov (United States)

    Chagas, Pietro Maria; Rosa, Suzan Gonçalves; Sari, Marcel Henrique Marcondes; Oliveira, Carla Elena Sartori; Canto, Rômulo Faria Santos; da Luz, Sônia Cristina Almeida; Braga, Antonio Luiz; Nogueira, Cristina Wayne

    2014-03-01

    The present study evaluated the antinociceptive and anti-inflammatory effects of per oral (p.o.) administration of salicylic acid-derivative organoselenium compounds in chemical models of nociception in mice. The compounds (50 mg/kg; p.o.) were administered 30 and 60 min before the nociceptive behavior and compared to the positive-control, acetylsalicylic acid (ASA; 200 mg/kg; p.o.). In addition, a dose-response curve (25-100 mg/kg) for compounds was carried out in the formalin test. When assessed in the chemical models, acetic acid-induced writhing behavior, formalin and glutamate tests, the compounds showed the following antinociceptive profile 1B>2B>1A>2A, suggesting a chemical structure-dependent relationship. Then, the anti-inflammatory properties and toxicological potential of compound 1B were investigated. Compound 1B, similar to the positive-control, ASA, diminished the edema formation and decreased the myeloperoxidase activity induced by croton oil (2.5%) in the ear tissue. The results also indicate that a single oral administration of 1B caused neither signs of acute toxicity nor those of gastrointestinal injury. The administration of 1B did not alter the water and food intakes, plasma alanine and aspartate aminotransferase activities or urea levels and cerebral or hepatic δ-aminolevulinate dehydratase activity. Salicylic acid-derivative organoseleniums, mainly compound 1B, have been found to be novel compounds with antinociceptive/anti-inflammatory properties; nevertheless, more studies are required to examine their therapeutic potential for pain treatment. Copyright © 2014 Elsevier Inc. All rights reserved.

  6. Modifying surface properties of KIT-6 zeolite with Ni and V for enhancing catalytic CO methanation

    Science.gov (United States)

    Cao, Hong-Xia; Zhang, Jun; Guo, Cheng-Long; Chen, Jingguang G.; Ren, Xiang-Kun

    2017-12-01

    The surface of the KIT-6 zeolite was modified with different amounts of Ni and V to promote the catalytic properties for CO methanation. A series of xNi-yV/KIT-6 with various Ni and V contents were prepared by the incipient-wetness impregnation method. The modified surfaces were characterized using N2 adsorption-desorption, Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD), hydrogen temperature-programmed reduction (H2-TPR), Fourier transformed infrared spectroscopy (FT-IR), Raman, X-ray photoelectron spectroscopy (XPS), transmission electron microscope (TEM), and energy-dispersive X-ray spectroscopy (EDX), respectively. The characterization results illustrated that the modification of V species was able to significantly promote low-temperature catalytic performance below 350 °C compared to that of unmodified Ni/KIT-6, which was likely due to an increase in the H2 uptake accompanied by enhanced CO dissociation derived from stronger electron transfer from V species to Ni0. Correspondingly, the xNi-yV/KIT-6 catalysts exhibited a distinct enhancement in CO conversion, CH4 selectivity and CH4 yield over unmodified Ni/KIT-6. Among all catalysts, 20Ni-2V/KIT-6 showed the best catalytic performance, corresponding to nearly 100% CO conversion and 85% CH4 yield at a low temperature of 300 °C. Furthermore, 20Ni-2V/KIT-6 presented enhanced coking-resistant and anti-sintering properties during a 60h-lifetime test at 500 °C and 1 atm with a high weight hourly space velocity (WHSV) of 60000 ml/g/h.

  7. Development of high performance refractory fibers with enhanced insulating properties and longer service lifetimes

    Energy Technology Data Exchange (ETDEWEB)

    Martin, P.C.; DePoorter, G.L.; Munoz, D.R.

    1991-02-01

    We have initiated a three phase investigation of the development of high performance refractory fibers with enhanced insulating properties and longer usable lifetimes. This report presents the results of the first phase of the study, performed from Aug. 1989 through Feb. 1991, which shows that significant energy saving are possible through the use of high temperature insulating fibers that better retain their efficient insulating properties during the service lifetime of the fibers. The remaining phases of this program include the pilot scale development and then full scale production feasibility development and evaluation of enhanced high temperature refractory insulting fibers. This first proof of principle phase of the program presents a summary of the current use patterns of refractory fibers, a laboratory evaluation of the high temperature performance characteristics of selected typical refractory fibers and an analysis of the potential energy savings through the use of enhanced refractory fibers. The current use patterns of refractory fibers span a wide range of industries and high temperature furnaces within those industries. The majority of high temperature fiber applications are in furnaces operating between 2000 and 26000{degrees}F. The fibers used in furnaces operating within this range provide attractive thermal resistance and low thermal storage at reasonable cost. A series of heat treatment studies performed for this phase of the program has shown that the refractory fibers, as initially manufactured, have attractive thermal conductivities for high temperature applications but the fibers go through rapid devitrification and subsequent crystal growth upon high temperature exposure. Development of improved fibers, maintaining the favorable characteristics of the existing as-manufactured fibers, could save between 1 and 4% of the energy consumed in high temperature furnaces using refractory fibers.

  8. Functionalized Polymeric Membrane with Enhanced Mechanical and Biological Properties to Control the Degradation of Magnesium Alloy.

    Science.gov (United States)

    Wong, Hoi Man; Zhao, Ying; Leung, Frankie K L; Xi, Tingfei; Zhang, Zhixiong; Zheng, Yufeng; Wu, Shuilin; Luk, Keith D K; Cheung, Kenneth M C; Chu, Paul K; Yeung, Kelvin W K

    2017-04-01

    To achieve enhanced biological response and controlled degradation of magnesium alloy, a modified biodegradable polymer coating called polycaprolactone (PCL) is fabricated by a thermal approach in which the heat treatment neither alters the chemical composition of the PCL membrane nor the rate of magnesium ion release, pH value, or weight loss, compared with the untreated sample. The changes in the crystallinity, hydrophilicity, and oxygen content of heat-treated PCL coating not only improve the mechanical adhesion strength between the coating and magnesium substrate but also enhance the biological properties. Moreover, the thermally modified sample can lead to higher spreading and elongation of osteoblasts, due to the enhanced hydrophilicity and CO to CO functional group ratio. In the analyses of microcomputed tomography from one to four weeks postoperation, the total volume of new bone formation on the heat-treated sample is 10%-35% and 70%-90% higher than that of the untreated and uncoated controls, respectively. Surprisingly, the indentation modulus of the newly formed bone adjacent to the heat-treated sample is ≈20% higher than that of both controls. These promising results reveal the clinical potential of the modified PCL coating on magnesium alloy in orthopedic applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Enhancement of Field Emission Properties of Carbon Nanotubes by ECR-Plasma Treatment

    Directory of Open Access Journals (Sweden)

    Javid Ali

    2014-01-01

    Full Text Available We report a significant improvement in electron field emission property of carbon nanotubes film by using an electron cyclotron resonance plasma treatment. Our research results reveal that plasma treatment can modify the surface morphology and enhance the field emission characteristics of carbon nanotubes. Raman spectra indicate that plasma treated CNTs sample has lesser defects. Before plasma treatment, low current density of 6.5 mA/cm2 at 3.0 V/μm and at a high turn-on field Eto of 2.4 V/μm was observed. ECR plasma treated CNTs showed a high current density of 20.0 mA/cm2 at 3.0 V/μm and at a low Eto of 1.6 V/μm. The calculated enhancement factors are 694 and 8721 for ECR-plasma untreated and treated carbon nanotubes, respectively. We found an increase in the enhancement factor and emission current after the ECR-plasma treatment. This may be attributed to creation of geometrical features through the removal of amorphous carbon and catalyst particles.

  10. Novel GQD-PVP-CdS composite with enhanced visible-light-driven photocatalytic properties

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Tao; Li, Yinle; Shen, Jianfeng, E-mail: jfshen@fudan.edu.cn; Ye, Mingxin, E-mail: mxye@fudan.edu.cn

    2016-03-30

    Graphical abstract: - Highlights: • GQD-PVP-CdS composite was prepared for the first time through a facile hydrothermal route. • GQD-PVP-CdS demonstrated outstanding photoactivity under visible light illumination. • GQDs and polymeric material are compounded with CdS nanoparticles simultaneously for the first time. • The addition of GQDs plays pivotal roles in the enhancement of the photoactivity. - Abstract: A facile one-step hydrothermal method to synthesize graphene quantum dots (GQDs)-polyvinyl pyrrolidone (PVP)-CdS nanocomposite was reported. The nanocomposite was thoroughly characterized with X-ray diffraction, transmission electron microscopy, scanning electron microscopy, Fourier-transform infrared spectroscopy, Raman spectroscopy, X-ray photoelectron spectroscopy and ultraviolet–visible spectroscopy. The results confirmed the formation of GQD-PVP-CdS composite with a uniform size (5–10 nm) and a relatively low band gap (E{sub g} = 2.23 eV). Moreover, the as-prepared composite exhibited enhanced photocatalytic activity toward the degradation of organic contaminants, with 92.3% of methyl orange (10 mg/L) removed after 3 hours of visible light illumination. This enhancement in photocatalytic activity was postulated to be attributed to the upconversion property of GQDs and a more efficient charge distribution between GQDs and CdS particles.

  11. Tumor Cell Malignant Properties Are Enhanced by Circulating Exosomes in Sleep Apnea.

    Science.gov (United States)

    Almendros, Isaac; Khalyfa, Abdelnaby; Trzepizur, Wojciech; Gileles-Hillel, Alex; Huang, Lei; Akbarpour, Mahzad; Andrade, Jorge; Farré, Ramon; Gozal, David

    2016-11-01

    OSA is associated with increased cancer incidence and mortality. Exosomes are vesicles secreted by most cells. They are released into the bloodstream and play a role in tumor progression and metastasis. We evaluated whether the chronic intermittent hypoxia (IH) that characterizes OSA leads to release of tumor-promoting exosomes in the circulation. C57/B6 male mice were randomized to 6 weeks of IH or room air (RA). A subgroup was injected with TC1 lung carcinoma cells in the left flank after 2 weeks of IH. Exosomes from mouse plasma and from 10 adult human patients with OSA before and after treatment for 6 weeks were cocultured with mouse TC1 and human adenocarcinoma cells lines. Malignant tumor properties such as proliferation, migration, invasion, and endothelial monolayer disruption were assessed, as was micro-RNA (miRNA), exosomal content, and transcriptomic effects of exosomes on TC1 cells in vitro to identify target genes. Application of IH-induced exosomes from either IH-exposed tumor-bearing (IH+) or non-tumor-bearing (IH-) mice significantly promoted TC1 malignant properties. Similarly, before adherent treatment, exosomes from patients with OSA significantly enhanced proliferation and migration of human adenocarcinoma cells compared with after adherent treatment. Eleven distinct miRNAs emerged in IH-exposed mice, and their gene targets in TC1 cells were identified. Circulating exosomes released under IH conditions in vivo selectively enhance specific properties of lung tumor cell cultures. Thus, plasma exosomes participate in the increased tumor aggressiveness observed in patients with OSA. Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.

  12. Detailed Characterization of the In Vitro Pharmacological and Pharmacokinetic Properties ofN-(2-Hydroxybenzyl)-2,5-Dimethoxy-4-Cyanophenylethylamine (25CN-NBOH), a Highly Selective and Brain-Penetrant 5-HT2AReceptor Agonist.

    Science.gov (United States)

    Jensen, Anders A; McCorvy, John D; Leth-Petersen, Sebastian; Bundgaard, Christoffer; Liebscher, Gudrun; Kenakin, Terry P; Bräuner-Osborne, Hans; Kehler, Jan; Kristensen, Jesper Langgaard

    2017-06-01

    Therapeutic interest in augmentation of 5-hydroxytryptamine 2A (5-HT 2A ) receptor signaling has been renewed by the effectiveness of psychedelic drugs in the treatment of various psychiatric conditions. In this study, we have further characterized the pharmacological properties of the recently developed 5-HT 2 receptor agonist N -2-hydroxybenzyl)-2,5-dimethoxy-4-cyanophenylethylamine (25CN-NBOH) and three structural analogs at recombinant 5-HT 2A , 5-HT 2B , and 5-HT 2C receptors and investigated the pharmacokinetic properties of the compound. 25CN-NBOH displayed robust 5-HT 2A selectivity in [ 3 H]ketanserin/[ 3 H]mesulergine, [ 3 H]lysergic acid diethylamide and [ 3 H]Cimbi-36 binding assays ( K i 2C / K i 2A ratio range of 52-81; K i 2B / K i 2A ratio of 37). Moreover, in inositol phosphate and intracellular Ca 2+ mobilization assays 25CN-NBOH exhibited 30- to 180-fold 5-HT 2A /5-HT 2C selectivities and 54-fold 5-HT 2A /5-HT 2B selectivity as measured by Δlog( R max /EC 50 ) values. In an off-target screening 25CN-NBOH (10 μ M) displayed either substantially weaker activity or inactivity at a plethora of other receptors, transporters, and kinases. In a toxicological screening, 25CN-NBOH (100 μ M) displayed a benign acute cellular toxicological profile. 25CN-NBOH displayed high in vitro permeability (P app = 29 × 10 -6 cm/s) and low P-glycoprotein-mediated efflux in a conventional model of cellular transport barriers. In vivo, administration of 25CN-NBOH (3 mg/kg, s.c.) in C57BL/6 mice mice produced plasma and brain concentrations of the free (unbound) compound of ∼200 nM within 15 minutes, further supporting that 25CN-NBOH rapidly penetrates the blood-brain barrier and is not subjected to significant efflux. In conclusion, 25CN-NBOH appears to be a superior selective and brain-penetrant 5-HT 2A receptor agonist compared with (±)-2,5-dimethoxy-4-iodoamphetamine (DOI), and thus we propose that the compound could be a valuable tool for future investigations

  13. Pharmacological treatment of obesity

    OpenAIRE

    Mancini, Marcio C; HALPERN, Alfredo

    2006-01-01

    This review offers an overview of physiological agents, current therapeutics, as well as medications, which have been extensively used and those agents not currently available or non-classically considered anti-obesity drugs. As obesity - particularly that of central distribution - represents an important triggering factor for insulin resistance, its pharmacological treatment is relevant in the context of metabolic syndrome control. The authors present an extensive review on the criteria for ...

  14. Enhancement of anti-inflammatory property of aspirin in mice by a nano-emulsion preparation.

    Science.gov (United States)

    Subramanian, Balajikarthick; Kuo, Fonghsu; Ada, Earl; Kotyla, Tim; Wilson, Thomas; Yoganathan, Subbiah; Nicolosi, Robert

    2008-11-01

    Aspirin, a non-steroidal anti-inflammatory drug, widely used for its anti-inflammatory properties is associated with several systemic side effects including gastro-intestinal discomfort. Inflammation can be mediated by pro-inflammatory cytokines and, along with various other host factors eventually give rise to edema at the inflamed site. Because of the adverse side effects oftentimes associated with systemic exposure to aspirin, the aim of the present study was to investigate whether the anti-inflammatory property of aspirin would enhance if delivered as nano-emulsion preparation. Nano-emulsion preparations of aspirin prepared with a Microfluidizer Processor were evaluated in the croton-oil-induced ear edema CD-1 mouse model using ear lobe thickness and the accumulation of specific in situ cytokines as biomarkers of inflammation. The results showed that particle size (90 nm) populations of nano-emulsion preparations of aspirin compared to an aspirin suspension (363 nm), significantly decreased (pemulsion further reduced the auricular levels of IL-1alpha (-37%) and TNFalpha (-69%) compared to the aspirin suspension preparation (pemulsion preparation of aspirin significantly improved the anti-inflammatory properties of an aspirin suspension in a CD-1 mouse model of induced inflammation.

  15. Enhancing the Properties of Carbon and Gold Substrates by Surface Modification

    Energy Technology Data Exchange (ETDEWEB)

    Harnisch, Jennifer Anne [Iowa State Univ., Ames, IA (United States)

    2001-01-01

    The properties of both carbon and gold substrates are easily affected by the judicious choice of a surface modification protocol. Several such processes for altering surface composition have been published in literature. The research presented in this thesis primarily focuses on the development of on-column methods to modify carbon stationary phases used in electrochemically modulated liquid chromatography (EMLC). To this end, both porous graphitic carbon (PGC) and glassy carbon (GC) particles have been modified on-column by the electroreduction of arenediazonium salts and the oxidation of arylacetate anions (the Kolbe reaction). Once modified, the carbon stationary phases show enhanced chromatographic performance both in conventional liquid chromatographic columns and EMLC columns. Additionally, one may also exploit the creation of aryl films to by electroreduction of arenediazonium salts in the creation of nanostructured materials. The formation of mercaptobenzene film on the surface of a GC electrode provides a linking platform for the chemisorption of gold nanoparticles. After deposition of nanoparticles, the surface chemistry of the gold can be further altered by self-assembled monolayer (SAM) formation via the chemisorption of a second thiol species. Finally, the properties of gold films can be altered such that they display carbon-like behavior through the formation of benzenehexathiol (BHT) SAMs. BHT chemisorbs to the gold surface in a previously unprecedented planar fashion. Carbon and gold substrates can be chemically altered by several methodologies resulting in new surface properties. The development of modification protocols and their application in the analytical arena is considered herein.

  16. Activating "Invisible" Glue: Using Electron Beam for Enhancement of Interfacial Properties of Graphene-Metal Contact.

    Science.gov (United States)

    Kim, Songkil; Russell, Michael; Kulkarni, Dhaval D; Henry, Mathias; Kim, Steve; Naik, Rajesh R; Voevodin, Andrey A; Jang, Seung Soon; Tsukruk, Vladimir V; Fedorov, Andrei G

    2016-01-26

    Interfacial contact of two-dimensional graphene with three-dimensional metal electrodes is crucial to engineering high-performance graphene-based nanodevices with superior performance. Here, we report on the development of a rapid "nanowelding" method for enhancing properties of interface to graphene buried under metal electrodes using a focused electron beam induced deposition (FEBID). High energy electron irradiation activates two-dimensional graphene structure by generation of structural defects at the interface to metal contacts with subsequent strong bonding via FEBID of an atomically thin graphitic interlayer formed by low energy secondary electron-assisted dissociation of entrapped hydrocarbon contaminants. Comprehensive investigation is conducted to demonstrate formation of the FEBID graphitic interlayer and its impact on contact properties of graphene devices achieved via strong electromechanical coupling at graphene-metal interfaces. Reduction of the device electrical resistance by ∼50% at a Dirac point and by ∼30% at the gate voltage far from the Dirac point is obtained with concurrent improvement in thermomechanical reliability of the contact interface. Importantly, the process is rapid and has an excellent insertion potential into a conventional fabrication workflow of graphene-based nanodevices through single-step postprocessing modification of interfacial properties at the buried heterogeneous contact.

  17. Combination of magnetic and enhanced mechanical properties for copolymer-grafted magnetite composite thermoplastic elastomers.

    Science.gov (United States)

    Jiang, Feng; Zhang, Yaqiong; Wang, Zhongkai; Wang, Wentao; Xu, Zhaohua; Wang, Zhigang

    2015-05-20

    Composite thermoplastic elastomers (CTPEs) of magnetic copolymer-grafted nanoparticles (magnetite, Fe3O4) were synthesized and characterized to generate magnetic CTPEs, which combined the magnetic property of Fe3O4 nanoparticles and the thermoplastic elasticity of the grafted amorphous polymer matrix. Fe3O4 nanoparticles served as stiff, multiple physical cross-linking points homogeneously dispersed in the grafted poly(n-butyl acrylate-co-methyl methacrylate) rubbery matrix synthesized via the activators regenerated by electron transfer for atom transfer radical polymerization method (ARGET ATRP). The preparation technique for magnetic CTPEs opened a new route toward developing a wide spectrum of magnetic elastomeric materials with strongly enhanced macroscopic properties. Differential scanning calorimetry (DSC) was used to measure the glass transition temperatures, and thermogravimetric analysis (TGA) was used to examine thermal stabilities of these CTPEs. The magnetic property could be conveniently tuned by adjusting the content of Fe3O4 nanoparticles in CTPEs. Compared to their linear copolymers, these magnetic CTPEs showed significant increases in tensile strength and elastic recovery. In situ small-angle X-ray scattering measurement was conducted to reveal the microstructural evolution of CTPEs during tensile deformation.

  18. Facile synthesis of Cu/tetrapod-like ZnO whisker compounds with enhanced photocatalytic properties

    Science.gov (United States)

    Liu, Hong; Liu, Huarong; Fan, Ximei

    2017-09-01

    Cu/tetrapod-like ZnO whisker (T-ZnOw) compounds were successfully synthesized using N2H4 \\cdot H2O as a reducing agent by a simple reduction method without any insert gas at room temperature. The crystal phase composition and morphology of the as-prepared samples were investigated by XRD, SEM and FESEM tests. The photocatalytic property of the as-prepared samples was detected by the degradation of methyl orange (MO) aqueous solution under UV irradiation. It can be found that Cu nanoparticles (CuNPs) dispersed on the surface of T-ZnOw increased with the increasing of Cu/Zn molar ratios (Cu/Zn MRs), and an octahedral structure of CuNPs was obtained when the sample was prepared with less than and equal to 7.30% Cu/Zn MR, but tended to a spherical or nanorod structure of CuNPs densely arranged on the surface of T-ZnOw, which is prepared by Cu/Zn MRs up to 22.00%. All the compounds exhibited excellent photocatalytic activity in decomposing of MO than T-ZnOw, the photocatalytic property of the samples increased with the increasing of Cu/Zn MRs up to 7.30%, while it decreases when further increasing the Cu/Zn MRs. The Schottky barrier of the Cu/T-ZnOw compound can effectively capture photoinduced electrons from the interface and enhanced the photocatalytic property of T-ZnOw.

  19. Social Pharmacology: Expanding horizons

    Science.gov (United States)

    Maiti, Rituparna; Alloza, José Luis

    2014-01-01

    In the current modern and global society, social changes are in constant evolution due to scientific progress (technology, culture, customs, and hygiene) and produce the freedom in individuals to take decisions by themselves or with their doctors toward drug consumption. In the arena of marketed drug products which includes society, individual, administration, and pharmaceutical industry, the young discipline emerged is social pharmacology or sociopharmacology. This science arises from clinical pharmacology, and deals with different parameters, which are important in creating knowledge on marketed drugs. However, the scope of “social pharmacology” is not covered by the so-called “Phase IV” alone, but it is the science that handles the postmarketing knowledge of drugs. The social pharmacology studies the “life cycle” of any marketed pharmaceutical product in the social terrain, and evaluates the effects of the real environment under circumstances totally different in the drug development process. Therefore, there are far-reaching horizons, plural, and shared predictions among health professionals and other, for beneficial use of a drug, toward maximizing the benefits of therapy, while minimizing negative social consequences. PMID:24987168

  20. Epigenetics and pharmacology.

    Science.gov (United States)

    Stefanska, Barbara; MacEwan, David J

    2015-06-01

    Recent advances in the understanding of gene regulation have shown there to be much more regulation of the genome than first thought, through epigenetic mechanisms. These epigenetic mechanisms are systems that have evolved to either switch off gene activity altogether, or fine-tune any existing genetic activation. Such systems are present in all genes and include chromatin modifications and remodelling, DNA methylation (such as CpG island methylation rates) and histone covalent modifications (e.g. acetylation, methylation), RNA interference by short interfering RNAs (siRNAs) and long non-coding RNAs (ncRNAs). These systems regulate genomic activity 'beyond' simple transcriptional factor inducer or repressor function of genes to generate mRNA. Epigenetic regulation of gene activity has been shown to be important in maintaining normal phenotypic activity of cells, as well as having a role in development and diseases such as cancer and neurodegenerative disorders such as Alzheimer's. Newer classes of drugs regulate epigenetic mechanisms to counteract disease states in humans. The reports in this issue describe some advances in epigenetic understanding that relate to human disease, and our ability to control these mechanisms by pharmacological means. Increasingly the importance of epigenetics is being uncovered - it is pharmacology that will have to keep pace. © 2015 The British Pharmacological Society.

  1. gamma-Aminobutyric acid esters. 3. Synthesis, brain uptake, and pharmacological properties of C-18 glyceryl lipid esters of GABA with varying degree of unsaturation.

    Science.gov (United States)

    Jacob, J N; Hesse, G W; Shashoua, V E

    1987-09-01

    A series of 14C-labeled and unlabeled di-gamma-aminobutyric acid esters of glyceryl lipids having zero to three double bonds (stearoyl, oleoyl, linoleoyl, and linolenoyl) were synthesized. Measurements of the octanol/water partition coefficients of the compounds showed an increase with decreasing number of double bonds (i.e., from linolenoyl to stearoyl). The brain-uptake index went up from 31.5 (linolenoyl) to 45.1 (stearoyl) and similarly the brain-penetration index went up from 15 (linolenoyl) to 28 (stearoyl). Intraperitoneal injections of these di-GABA lipid esters produced a substantial inhibition of the general motor activity in mice at a dose of 30 mg/kg; the most active molecules were those containing two and three double bonds, i.e., the linolenoyl and linolenoyl derivatives. This is in reverse order to that predicted by brain-uptake and lipid-solubility properties, suggesting that the structure of the fatty acid side chain may be an additional factor in influencing biological activity.

  2. Effect of gas sparging on flux enhancement and phytochemical properties of clarified pineapple juice by microfiltration

    KAUST Repository

    Laorko, Aporn

    2011-08-01

    Membrane fouling is a major obstacle in the application of microfiltration. Several techniques have been proposed to enhance the permeate flux during microfiltration. Gas sparging is a hydrodynamic method for improving the performance of the membrane process. In this study, a 0.2 μm hollow fiber microfiltration membrane was used to study the effect of cross flow velocity (CFV) and gas injection factor () on the critical and limiting flux during microfiltration of pineapple juice. In addition, the phytochemical properties of clarified juice were investigated. In the absence of gas sparging, the critical and limiting flux increased as the CFV or shear stress number increased. The use of gas sparging led to a remarkable improvement in both the critical and limiting flux but it was more effective at the lower CFV (1.5 m s-1), compared to those at higher CFV (2.0 and 2.5 m s-1). When the gas injection factor was applied at 0.15, 0.25 and 0.35 with a CFV of 1.5 m s -1, the enhancement of 55.6%, 75.5% and 128.2% was achieved for critical flux, while 65.8%, 69.7% and 95.2% was achieved for limiting flux, respectively. The results also indicated that the use of gas sparging was an effective method to reduce reversible fouling and external irreversible fouling rather than internal irreversible fouling. In addition, the CFV and gas sparging did not affect pH, total soluble solids, colour, total phenolic content and the antioxidant property of the clarified juice. The l-ascorbic acid and total vitamin C were significantly decreased when the higher CFV and high gas injection factor were applied. The results also indicated that the use of gas sparging with low CFV was beneficial for flux enhancement while most of the phytochemical properties of the clarified juice was preserved. © 2011 Elsevier B.V. All rights reserved.

  3. Wet Chemical Controllable Synthesis of Hematite Ellipsoids with Structurally Enhanced Visible Light Property

    Directory of Open Access Journals (Sweden)

    Chengliang Han

    2013-01-01

    Full Text Available A facile and economic route has been presented for mass production of micro/nanostructured hematite microcrystals based on the wet chemical controllable method. The as-prepared samples were characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and UV-Vis absorption spectroscopy. The results showed that the product was mesoporous α-Fe2O3 and nearly elliptical in shape. Each hematite ellipsoid was packed by many α-Fe2O3 nanoparticles. The values of vapor pressure in reaction systems played vital roles in the formation of porous hematite ellipsoids. Optical tests demonstrated that the micro/nanostructured elliptical hematite exhibited enhanced visible light property at room temperature. The formation of these porous hematite ellipsoids could be attributed to the vapor pressure induced oriented assembling of lots of α-Fe2O3 nanoparticles.

  4. Improved thermoelectric properties of TiNiSn through enhancing strain field fluctuation

    Science.gov (United States)

    Lkhagvasuren, Enkhtaivan; Fu, Chenguang; Fecher, Gerhard H.; Auffermann, Gudrun; Kreiner, Guido; Schnelle, Walter; Felser, Claudia

    2017-10-01

    MNiSn (M  =  Hf, Zr, Ti) -based half Heusler compounds have attracted extensive attention as promising materials in thermoelectric power generation. In this work, the thermoelectric properties of the cheapest composition TiNiSn from this system are investigated. Isoelectronic substitutions of Si and Ge on Sn site are employed to reduce the lattice thermal conductivity. It is found that Si substitution leads to simultaneously enhanced mass and strain field fluctuations in TiNiSn, while the strain field fluctuation dominates the decrease of thermal conductivity in Ge substituted TiNiSn. A maximum ZT of 0.48 at 740 K is obtained in TiNiSn0.975 Ge0.025 , which is a 23% increase compared to TiNiSn. This result highlights the role of strain field fluctuation in suppressing lattice thermal conductivity and improving the thermoelectric performance of half-Heusler compounds.

  5. Anisotropically Enhanced Nonlinear Optical Properties of Ensembles of Gold Nanorods Electrospun in Polymer Nanofiber Film.

    Science.gov (United States)

    Zhang, Hang; Hu, Zhongliang; Ma, Zhijun; Gecevičius, Mindaugas; Dong, Guoping; Zhou, Shifeng; Qiu, Jianrong

    2016-01-27

    Polymeric nanofibers containing gold nanorods (GNRs) are aligned in a uniform orientation through electrospinning. The dispersive and absorptive parts of the third-order optical nonlinear optical refractive index of the composite film measured by polarization dependent z-scan method are demonstrated to be anisotropically enhanced. Anisotropic optical response of the aligned GNRs and its connection with the ultrafast electron dynamics are discussed in light of the results of resonant femtosecond pump-probe experiments. The significant appearance of anisotropic nonlinear optical properties of ensembles of GNRs is attributed to the sensitive excitation of longitudinal surface plasmon resonance (LSPR) of highly aligned GNRs. For the macroscopic applications of ensembles of GNRs, such as passive mode-locking and all-optical switching, the experimental results demonstrate that the alignment of GNRs through electrospinning should be very high efficient, and economic.

  6. Wet chemical controllable synthesis of hematite ellipsoids with structurally enhanced visible light property.

    Science.gov (United States)

    Han, Chengliang; Han, Jie; Li, Qiankun; Xie, Jingsong

    2013-01-01

    A facile and economic route has been presented for mass production of micro/nanostructured hematite microcrystals based on the wet chemical controllable method. The as-prepared samples were characterized using X-ray diffraction, scanning electron microscopy, transmission electron microscopy, and UV-Vis absorption spectroscopy. The results showed that the product was mesoporous α -Fe2O3 and nearly elliptical in shape. Each hematite ellipsoid was packed by many α -Fe2O3 nanoparticles. The values of vapor pressure in reaction systems played vital roles in the formation of porous hematite ellipsoids. Optical tests demonstrated that the micro/nanostructured elliptical hematite exhibited enhanced visible light property at room temperature. The formation of these porous hematite ellipsoids could be attributed to the vapor pressure induced oriented assembling of lots of α -Fe2O3 nanoparticles.

  7. Retracted-Enhanced X-Ray Absorption Property of Gold-Doped Single Wall Carbon Nanotube

    Directory of Open Access Journals (Sweden)

    Alimin Alimin

    2015-11-01

    Full Text Available Enhanced X-ray absorption property of single wall carbon nanotube (SWCNT through gold (Au doping (Au@SWCNT has been studied. Mass attenuation coefficient of SWCNT increased 5.2-fold after Au doping treatment. The use of ethanol in the liquid phase adsorption could produce Au nanoparticles as confirmed by the X-ray Diffraction (XRD patterns. The possibility of gold nanoparticles encapsulated in the internal tube space of SWCNT was observed by transmission electron microscope technique. A significant decrease of nitrogen uptakes and upshifts of Radial Breathing Mode (RBM of Au@SWCNT specimen suggest that the nanoparticles might be encapsulated in the internal tube spaces of the nanotube. In addition, a decrease intensity of XRD pattern of Au@SWCNT at around 2θ ≈ 2.6° supports the suggestion that Au nanoparticles are really encapsulated into SWCNT.

  8. Cold plasma welding of polyaniline nanofibers with enhanced electrical and mechanical properties

    Science.gov (United States)

    Ye, Dong; Yu, Yao; Liu, Lin; Lu, Xinpei; Wu, Yue

    2015-12-01

    Joining conducting polymer (CP) nanofibers into an interconnected porous network can result in good mechanical and electrical contacts between nanofibers that can be beneficial for the high performance of CP-based devices. Here, we demonstrate the cold welding of polyaniline (PAni) nanofiber loose ends with cold plasma. The room-temperature and atmospheric-pressure helium micro-plasma jet launches highly charged ion bullets at a PAni nanofiber target with high precision and the highly charged ion bullet selectively induces field emission at the sharp nanofiber loose ends. This technique joins nanofiber tips without altering the morphology of the film and protonation thus leading to significantly enhanced electrical and mechanical properties. In addition, this technique has high spatial resolution and is able to selectively weld and dope regions of nanofiber film with promising novel device applications.

  9. Considerations for Nanosciences in Food Science and Nutrition: "Enhanced Food Properties".

    Science.gov (United States)

    Tekiner, Ismail H; Mutlu, Hayrettin; Algıngil, Selcuk; Dincerler, Elif

    2015-01-01

    The agro-food industries are one of the biggest manufacturing sectors worldwide with a turnover of US$4 trillion per year. Within the last decades, nanoscience has opened-up fantastic ways to challenge new sub-universes for exploring the interactions between physical, chemical and biological systems as well as agro-food and nutrition sectors. Among these potentials, there is the enhancement of food properties and constituents such as nanoparticulate delivery systems, food safety and food biosecurity. In the recent years, many patents were launched for edible coating agents, essential oils and emulsifiers, including agrochemical active ingredients, nanomaterials for agriculture, horticulture, aquaculture, and smart packaging materials. The aim of this review was to search for the recent applications of nanoscience in the agro-food science and nutrition area, including the launched patents in this field.

  10. Gold nanotube encapsulation enhanced magnetic properties of transition metal monoatomic chains: An ab initio study.

    Science.gov (United States)

    Zhu, Liyan; Wang, Jinlan; Ding, Feng

    2009-02-14

    The magnetic properties of gold nanotubes encapsulated transition metal (TM, TM=Co and Mn) and monoatomic chains (TM@Au) are studied using first-principles density functional calculations. The TM chains are significantly stabilized by the gold nanotube coating. TM-TM distance-dependent ferromagnetic-antiferromagnetic phase transition in TM@Au is observed and can be understood by Ruderman-Kittel-Kasuya-Yosida (RKKY) model. The magnetocrystalline anisotropy energies of the TM@Au tubes are dramatically enhanced by one order of magnitude compared to those of free TM chains. Furthermore, the stronger interaction between Mn chain and gold nanotube even switches the easy magnetization axis along the tube.

  11. UDM enhanced physical and mechanical properties through the formation of nanocavities in an epoxy matrix.

    Science.gov (United States)

    Kumar, Kaushal; Kumar, Arun; Ghosh, P K

    2018-01-01

    The matrix modification of relatively low viscous epoxy based polymer treated under ultrasonic mixing (UM) and ultrasonic mixing with simultaneous stirring by a rotating impeller, referred to as ultrasonic dual mixing (UDM), and the effect of processing techniques has been investigated in terms of the formation of nanocavities in the epoxy matrix. Nanocavities of size 42±8nm have been formed uniformly in the epoxy matrix by UDM. The effect of a change in matrix morphology on the viscoelastic, tensile and thermal properties of the cured epoxy resin has been studied. The UDM processed cured epoxy matrix showed 18.26% and 88.34% improvement in tensile strength and toughness as compared to unprocessed epoxy. Thermal gravimetric analysis (TGA) of UDM processed epoxy showed significant enhancement in the thermal stability of the epoxy matrix. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Enhanced photovoltaic properties of perovskite solar cells by TiO2 homogeneous hybrid structure

    Science.gov (United States)

    Su, Pengyu; Fu, Wuyou; Yao, Huizhen; Liu, Li; Ding, Dong; Feng, Fei; Feng, Shuang; Xue, Yebin; Liu, Xizhe; Yang, Haibin

    2017-10-01

    In this paper, we fabricated a TiO2 homogeneous hybrid structure for application in perovskite solar cells (PSCs) under ambient conditions. Under the standard air mass 1.5 global (AM 1.5G) illumination, PSCs based on homogeneous hybrid structure present a maximum power conversion efficiency of 5.39% which is higher than that of pure TiO2 nanosheets. The enhanced properties can be explained by the better contact of TiO2 nanosheets/nanoparticles with CH3NH3PbI3 and fewer pinholes in electron transport materials. The advent of such unique structure opens up new avenues for the future development of high-efficiency photovoltaic cells.

  13. Enhanced microwave absorption properties of CTAB assisted Pr–Cu substituted nanomaterial

    Energy Technology Data Exchange (ETDEWEB)

    Sadiq, Imran, E-mail: Imran.cssp@pu.edu.pk [Centre of Excellence in Solid State Physics, University of the Punjab, Lahore (Pakistan); Naseem, Shahzad; Riaz, Saira [Centre of Excellence in Solid State Physics, University of the Punjab, Lahore (Pakistan); Khan, Hasan M. [Department of Physics, Bahauddin Zakariya University, Multan (Pakistan); Ashiq, Muhammad Naeem [Institute of Chemical Sciences, Bahauddin Zakariya University, Multan (Pakistan); Hussain, S. Sajjad; Rana, Mazhar [Centre of Excellence in Solid State Physics, University of the Punjab, Lahore (Pakistan)

    2016-09-15

    In this study, the rare earth Pr{sup 3+}and divalent Cu{sup 2+} elements substituted Sr{sub 1−x}Pr{sub x}Mn{sub 2}Fe{sub 16−y}Cu{sub y}O{sub 27} (x=0, 0.02, 0.06, 0.1 and y=0, 0.1, 0.3, 0.5) W-type hexagonal ferrites were prepared by Sol–Gel method. TGA and DSC analysis of as prepared material was carried out to confirm the temperature at which required phase can be obtained. The XRD patterns exhibit the single phase for all the samples and the lattice parameters were changed with the additives. The absorption bands at wave number 636 and 554 cm{sup −1} in FTIR spectrum indicate the stretching vibration of metal–oxygen ions which also ratifies the single phase for the prepared material. Microstructural analysis confirms the agglomeration of nanograins which leads to formation of platelet like structure which cause in the enhancement of the microwave absorption properties of material. The minimum reflection loss of −59.8 dB at 9.34 GHz frequency was observed makes the prepared material good candidate to be used in super high frequency application. The attenuation constant and reflectivity results are also in good agreement with minimum reflection losses results. - Highlights: • A series of W-type hexagonal ferrites were prepared by Sol–Gel method. • The XRD analysis showed that the W-type hexagonal structure. • The c/a ratio of these samples falls in the range of W-type hexagonal ferrites. • The FTIR spectrum also confirms the single W-type hexagonal phase. • The microwave absorption properties enhanced with Pr–Cu substitution.

  14. Enhancement of mechanical and electrical properties of continuous-fiber-reinforced epoxy composites with stacked graphene

    Science.gov (United States)

    Shepelev, Olga; Kenig, Samuel

    2017-01-01

    Impregnation of expandable graphite (EG) after thermal treatment with an epoxy resin containing surface-active agents (SAAs) enhanced the intercalation of epoxy monomer between EG layers and led to further exfoliation of the graphite, resulting in stacks of few graphene layers, so-called “stacked” graphene (SG). This process enabled electrical conductivity of cured epoxy/SG composites at lower percolation thresholds, and improved thermo-mechanical properties were measured with either Kevlar, carbon or glass-fiber-reinforced composites. Several compositions with SAA-modified SG led to higher dynamic moduli especially at high temperatures, reflecting the better wetting ability of the modified nanoparticles. The hydrophilic/hydrophobic nature of the SAA dictates the surface energy balance. More hydrophilic SAAs promoted localization of the SG at the Kevlar/epoxy interface, and morphology seems to be driven by thermodynamics, rather than the kinetic effect of viscosity. This effect was less obvious with carbon or glass fibers, due to the lower surface energy of the carbon fibers or some incompatibility with the glass-fiber sizing. Proper choice of the surfactant and fine-tuning of the crosslink density at the interphase may provide further enhancements in thermo-mechanical behavior. PMID:29046838

  15. Properties enhancement of Al-Zn-Mg alloy by retrogression and re-aging heat treatment

    Directory of Open Access Journals (Sweden)

    Zaid H.R.

    2011-01-01

    Full Text Available The higher strength 7xxx aluminum alloys exhibited low resistance to stress corrosion cracking (SCC when aged to the peak hardness (T6 temper. The overaged alloys (T7 temper developed to enhance the SCC with loss in the strength of the alloy. Recently, retrogression and re-aging (RRA heat treatments are used for improving the SCC behavior for alloys in T6 tempers such as 7075, 7475 and 8090. In this study, an application of retrogression and re-aging heat treatment processes are carried out to enhance toughness properties of the 7079-T651 aluminum alloy, while maintaining the higher strength of T651-temper. The results of charpy impact energy and electrical conductivity tests show a significantly increases in absorbed energy and electrical conductivity values, when the alloys are exposed to various retrogression temperatures (190, 200, 210°C and times (20, 40, 60 minutes, and then re-aged at 160°C for 18 hours.

  16. Enhancement of mechanical and electrical properties of continuous-fiber-reinforced epoxy composites with stacked graphene.

    Science.gov (United States)

    Naveh, Naum; Shepelev, Olga; Kenig, Samuel

    2017-01-01

    Impregnation of expandable graphite (EG) after thermal treatment with an epoxy resin containing surface-active agents (SAAs) enhanced the intercalation of epoxy monomer between EG layers and led to further exfoliation of the graphite, resulting in stacks of few graphene layers, so-called "stacked" graphene (SG). This process enabled electrical conductivity of cured epoxy/SG composites at lower percolation thresholds, and improved thermo-mechanical properties were measured with either Kevlar, carbon or glass-fiber-reinforced composites. Several compositions with SAA-modified SG led to higher dynamic moduli especially at high temperatures, reflecting the better wetting ability of the modified nanoparticles. The hydrophilic/hydrophobic nature of the SAA dictates the surface energy balance. More hydrophilic SAAs promoted localization of the SG at the Kevlar/epoxy interface, and morphology seems to be driven by thermodynamics, rather than the kinetic effect of viscosity. This effect was less obvious with carbon or glass fibers, due to the lower surface energy of the carbon fibers or some incompatibility with the glass-fiber sizing. Proper choice of the surfactant and fine-tuning of the crosslink density at the interphase may provide further enhancements in thermo-mechanical behavior.

  17. Attachment of metal nanoparticles to SnO2 nanowires for enhancement of gas sensing properties.

    Science.gov (United States)

    Woo, Hyoun Woo; Kwon, Yong Jung; Cho, Hong Yeon; Na, Han Gil

    2014-11-01

    We fabricated SnO2/cobalt (Co) core-shell nanowires by means of a two-step process, for their application as chemical sensors. For Co-functionalization, we synthesized SnO2-Co core-shell nanowires by the sputtering deposition of Co layers on the surface of networked SnO2 nanowires, subsequently transforming the continuous Co-shell layers into crystalline islands by thermal heating. While scanning electron microscopy (SEM) images of annealed core-shell nanowires exhibited a rough surface, transmission electron microscopy (TEM) images revealed that the roughness is related to the agglomeration of the sputtered Co layer. The X-ray diffraction (XRD) pattern and lattice-resolved TEM images coincidentally indicated that the agglomerated particles are comprised of a hexagonal Co phase. The NO2 sensing test revealed that the sensor response was enhanced by decoration with Co nanoparticles. In addition, both response and recovery times tended to decrease as a result of the Co-functionalization. This indicates that the Co-functionalized SnO2 nanowire sensors can be used to sense gases at very low concentrations. We discussed possible mechanisms for enhancing sensor properties by Co-functionalization. The NO2 gas sensing test demonstrated the ability of the Co-functionalization to provide higher sensitivity, shorter response time, and shorter recovery time than would bare SnO2 nanowires.

  18. Transparent TiO2-PMMA Nanohybrids of High Nanocrystallinity and Enhanced Nonlinear Optical Properties

    Science.gov (United States)

    Yuwono, Akhmad Herman; Xue, Junmin; Wang, John; Elim, Hendry Izaac; Ji, Wei

    Nanohybrid thin films of titania-polymethyl methacrylate (TiO2-PMMA) with varying degrees of nanocrystallinity have been successfully synthesized via an in-situ sol gel-polymerization route, assisted by subsequent thermal and water vapor treatments. Post-hydrothermal treatment by water vapor at relatively low temperatures led to a higher degree of crystallinity for TiO2 nanoparticles than the conventional thermal annealing. The degree of TiO2 crystallinity in the resulting nanohybrid films was studied by using XRD, FTIR, UV-Vis spectroscopies and HRTEM. The resulting nanohybrid thin films are highly transparent in the visible region, with an estimated band gap energies, Eg, close to that of anatase TiO2 (~ 3.20 eV). The nanocrystallinity level of TiO2 phase strongly affects both linear and nonlinear optical properties of the nanohybrids. A significant enhancement in linear refractive index, no, up to 1.780 and a third-order nonlinear optical susceptibility, χ(3) as high as 5.27 × 10-9 esu, were demonstrated with the nanohybrid exhibiting the enhanced TiO2 crystallinity and well-preserved PMMA matrix.

  19. Phase-Defined van der Waals Schottky Junctions with Significantly Enhanced Thermoelectric Properties.

    Science.gov (United States)

    Wang, Qiaoming; Yang, Liangliang; Zhou, Shengwen; Ye, Xianjun; Wang, Zhe; Zhu, Wenguang; McCluskey, Matthew D; Gu, Yi

    2017-07-06

    We demonstrate a van der Waals Schottky junction defined by crystalline phases of multilayer In 2 Se 3 . Besides ideal diode behaviors and the gate-tunable current rectification, the thermoelectric power is significantly enhanced in these junctions by more than three orders of magnitude compared with single-phase multilayer In 2 Se 3 , with the thermoelectric figure-of-merit approaching ∼1 at room temperature. Our results suggest that these significantly improved thermoelectric properties are not due to the 2D quantum confinement effects but instead are a consequence of the Schottky barrier at the junction interface, which leads to hot carrier transport and shifts the balance between thermally and field-driven currents. This "bulk" effect extends the advantages of van der Waals materials beyond the few-layer limit. Adopting such an approach of using energy barriers between van der Waals materials, where the interface states are minimal, is expected to enhance the thermoelectric performance in other 2D materials as well.

  20. A versatile chitosan/ZnO nanocomposite with enhanced antimicrobial properties.

    Science.gov (United States)

    Malini, Madasamy; Thirumavalavan, Munusamy; Yang, Wen-Yi; Lee, Jiunn-Fwu; Annadurai, Gurusamy

    2015-09-01

    Porous chitosan membrane was fabricated by casting method using silica particles. Simultaneously nano ZnO was synthesized by green-synthesis method using tung ting oolong tea extract. Chitosan membrane was combined with nano ZnO in order to increase its antimicrobial activity. Through observations obtained from various techniques such as XRD, SEM, FT-IR, UV-visible and fluorescence emission analyses, chitosan was seen to be able to incorporate nano ZnO in the nanocomposite membrane. A blue shift (from 360 to 335 nm) was observed in the UV-visible spectrum of nanocomposite and fluorescence emission intensity of nanocomposite was considerably lower than that of nano ZnO. Gram negative organism Klebsiella planticola (MTCC2727) and Gram positive organism Bacillus substilis (MTCC3053) were used to test the antibacterial and antifouling activities of newly synthesized nanocomposite chitosan/ZnO membrane. The nanocomposite chitosan/ZnO membrane promisingly inhibited the bacterial growth when compared with as-synthesized chitosan. Gram negative K. planticola (MTCC2727) was comparatively more susceptible for inhibition than that of Gram positive Bacillus substilis (MTCC3053). In conclusion, nanocomposite obtained in this study showed enhanced antibacterial and antifouling activities. We believed that the enhanced physical properties of nanocomposite achieved by incorporating nano ZnO in the chitosan matrix could be beneficial in various applications. Copyright © 2015 Elsevier B.V. All rights reserved.

  1. Enhanced Photobactericidal and Targeting Properties of a Cationic Porphyrin following the Attachment of Polymyxin B.

    Science.gov (United States)

    Le Guern, Florent; Sol, Vincent; Ouk, Catherine; Arnoux, Philippe; Frochot, Céline; Ouk, Tan-Sothea

    2017-09-20

    A novel compound consisting of a cationic porphyrin covalently attached to a derivative of polymyxin B has been synthesized and presents enhanced activity and targeting properties compared to the usual cationic porphyrins recognized as efficient photosensitizers in photodynamic antimicrobial chemotherapy (PACT). A synthesis pathway was established to preserve the bactericidal activity of the peptide. Accordingly, the N-terminal amino acid (l-2,4-diaminobutyric acid) of polymyxin B (PMB) was switched for a cysteine residue. Then, the resulting derivative of PMB was covalently bound to 5-(4-aminophenyl)-10,15,20-tri(4-N-methylpyridyl)-21H,23H-porphyrin using a thiol-maleimide "click" coupling. The peptide-coupled photosensitizer has demonstrated an improved PACT efficiency compared to the cationic porphyrin alone. This enhancement has been observed against Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli in particular. Flow cytometry analyses and confocal imaging microscopy demonstrated that the porphyrin-peptide conjugate selectively adhered to the cell walls of either Gram-positive or Gram-negative bacteria, thus justifying the damages induced by singlet oxygen production.

  2. Enhanced photocatalytic activity of C@ZnO core-shell nanostructures and its photoluminescence property

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Tao; Yu, Shanwen; Fang, Xiaoxin; Huang, Honghong; Li, Lun [School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan (China); Wang, Xiuyuan [College of Plant Science and Technology, Huazhong Agricultural University, Wuhan (China); Wang, Huihu, E-mail: wanghuihu@mail.hbut.edu.cn [School of Materials and Chemical Engineering, Hubei University of Technology, Wuhan (China); Hubei Provincial Key Laboratory of Green Materials for Light Industry, Hubei University of Technology, Wuhan (China)

    2016-12-15

    Highlights: • C@ZnO nanostructures were synthesized by a facile hydrothermal carbonization method. • Glucose content has a great influence on the microstructure of C@ZnO nanostructures. • An ultrathin amorphous carbon layer enhances the adsorption capacity of C@ZnO. • C@ZnO nanostructures exhibit the improved photocatalytic activity and stability. - Abstract: An ultrathin layer of amorphous carbon coated C@ZnO core-shell nanostructures were synthesized via a facile hydrothermal carbonization process using glucose as precursor in this work. X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and diffuse reflectance UV–vis spectroscopy (DRS) were used for the characterization of as-prepared samples. Photoluminescence (PL) properties of C@ZnO samples were investigated using PL spectroscopy. The microstructure analysis results show that the glucose content has a great influence on the size, morphology, crystallinity and surface chemical states of C@ZnO nanostructures. Moreover, the as-prepared C@ZnO core-shell nanostructures exhibit the enhanced photocatalytic activity and good photostability for methyl orange dye degradation due to its high adsorption ability and its improved optical characteristics.

  3. Enhanced photocurrent and photocatalytic properties of porous ZnO thin film by Ag nanoparticles

    Science.gov (United States)

    Lv, Jianguo; Zhu, Qianqian; Zeng, Zheng; Zhang, Miao; Yang, Jin; Zhao, Min; Wang, Wenhao; Cheng, Yuebing; He, Gang; Sun, Zhaoqi

    2017-12-01

    ZnO thin films were deposited using an electrodeposition method and porous morphologies could be achieved by annealing treatment. A variety of Ag nanoparticles were loaded on the surface of the ZnO thin films. Surface morphology, chemical composition, crystal phase and optical properties were characterized by scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), UV-vis spectrophotometer and micro-Raman spectroscopy. Evidence of Ag nanoparticles on the Ag-4/ZnO thin film was be verified by the SEM and XPS measurements. The XRD results indicated that the Ag nanoparticles had little effect on crystallinity of the thin films. The photoresponse and photocatalytic results indicated that the photocurrent and photocatalytic performance could be enhanced by moderate Ag nanoparticles modification on the surface of the ZnO thin film. The best photoresponse and photocatalytic activity in Ag-4/ZnO thin film results from the moderate Ag nanoparticles on the surface of ZnO thin film, which could enhanced separation and suppressed recombination of photogenerated electron-hole pairs.

  4. Enhanced Structural, Thermal, and Electrical Properties of Multiwalled Carbon Nanotubes Hybridized with Silver Nanoparticles

    Directory of Open Access Journals (Sweden)

    Yusliza Yusof

    2016-01-01

    Full Text Available The objective of this study is to evaluate the structural, thermal, and electrical properties of multiwalled carbon nanotubes (MWNT hybridized with silver nanoparticles (AgNP obtained via chemical reduction of aqueous silver salt assisted with sodium dodecyl sulphate (SDS as stabilizing agent. Transmission electron microscopy (TEM reveals microstructural analysis of the MWNT-Ag hybrids. The Fourier transform infrared (FTIR spectra prove the interactions between the AgNP and carboxyl groups of the MWNT. Raman spectra reveal that the D- to G-band intensity ratios ID/IG and ID′/IG increase upon the deposition of AgNP onto the surface of the MWNT. Thermogravimetric analysis (TGA shows that the MWNT-Ag hybrids decompose at a much faster rate and the weight loss decreased considerably due to the presence of AgNP. Nonlinearity of current-voltage (I-V curves indicates that electrical transport of pristine MWNT is enhanced when AgNP is induced as charge carriers in the MWNT-Ag hybrids. The threshold voltage Vth value for the MWNT doped with a maximum of 70 vol% of AgNP was substantially reduced by 65% relative to the pristine MWNT. The MWNT-Ag hybrids have a favourable electrical characteristic with a low threshold voltage that shows enhancement mode for field-effect transistor (FET applications.

  5. Enhancement of mechanical and electrical properties of continuous-fiber-reinforced epoxy composites with stacked graphene

    Directory of Open Access Journals (Sweden)

    Naum Naveh

    2017-09-01

    Full Text Available Impregnation of expandable graphite (EG after thermal treatment with an epoxy resin containing surface-active agents (SAAs enhanced the intercalation of epoxy monomer between EG layers and led to further exfoliation of the graphite, resulting in stacks of few graphene layers, so-called “stacked” graphene (SG. This process enabled electrical conductivity of cured epoxy/SG composites at lower percolation thresholds, and improved thermo-mechanical properties were measured with either Kevlar, carbon or glass-fiber-reinforced composites. Several compositions with SAA-modified SG led to higher dynamic moduli especially at high temperatures, reflecting the better wetting ability of the modified nanoparticles. The hydrophilic/hydrophobic nature of the SAA dictates the surface energy balance. More hydrophilic SAAs promoted localization of the SG at the Kevlar/epoxy interface, and morphology seems to be driven by thermodynamics, rather than the kinetic effect of viscosity. This effect was less obvious with carbon or glass fibers, due to the lower surface energy of the carbon fibers or some incompatibility with the glass-fiber sizing. Proper choice of the surfactant and fine-tuning of the crosslink density at the interphase may provide further enhancements in thermo-mechanical behavior.

  6. Molecular Pharmacology of Phytocannabinoids.

    Science.gov (United States)

    Turner, Sarah E; Williams, Claire M; Iversen, Leslie; Whalley, Benjamin J

    Cannabis sativa has been used for recreational, therapeutic and other uses for thousands of years. The plant contains more than 120 C21 terpenophenolic constituents named phytocannabinoids. The Δ9-tetrahydrocannabinol type class of phytocannabinoids comprises the largest proportion of the phytocannabinoid content. Δ9-tetrahydrocannabinol was first discovered in 1971. This led to the discovery of the endocannabinoid system in mammals, including the cannabinoid receptors CB1 and CB2. Δ9-Tetrahydrocannabinol exerts its well-known psychotropic effects through the CB1 receptor but this effect of Δ9-tetrahydrocannabinol has limited the use of cannabis medicinally, despite the therapeutic benefits of this phytocannabinoid. This has driven research into other targets outside the endocannabinoid system and has also driven research into the other non-psychotropic phytocannabinoids present in cannabis. This chapter presents an overview of the molecular pharmacology of the seven most thoroughly investigated phytocannabinoids, namely Δ9-tetrahydrocannabinol, Δ9-tetrahydrocannabivarin, cannabinol, cannabidiol, cannabidivarin, cannabigerol, and cannabichromene. The targets of these phytocannabinoids are defined both within the endocannabinoid system and beyond. The pharmacological effect of each individual phytocannabinoid is important in the overall therapeutic and recreational effect of cannabis and slight structural differences can elicit diverse and competing physiological effects. The proportion of each phytocannabinoid can be influenced by various factors such as growing conditions and extraction methods. It is therefore important to investigate the pharmacology of these seven phytocannabinoids further, and characterise the large number of other phytocannabinoids in order to better understand their contributions to the therapeutic and recreational effects claimed for the whole cannabis plant and its extracts.

  7. Relationship between enhanced dewaterability and structural properties of hydrothermal sludge after hydrothermal treatment of excess sludge.

    Science.gov (United States)

    Wang, Liping; Li, Aimin; Chang, Yuzhi

    2017-04-01

    Hydrothermal treatment is an effective method to enhance the deep dewaterability of excess sludge with low energy consumption. In this study, an insight into the relationship between enhanced dewaterability and structural properties of the produced hydrothermal sludge was presented, aiming at better understanding the effect of hydrothermal process on excess sludge dewatering performance. The results indicated that hydrothermal effect induced the transformation of surface water to interstitial and free water by lowering the binding strength between adjacent water and solid particles and that free water became the main form for moisture existence in hydrothermal sludge as temperature was higher than 180 °C. Increase in temperature of hydrothermal treatment generated a significant size reduction of sludge flocs but treated sludge with a higher rigidity, which not only strengthened the network of hydrothermal sludge but also destroyed the binding of EPS with water. Hydrothermal process caused crevice and pore structures of excess sludge to disappear gradually, which was a main driving force of water removal as temperature was below 150 °C. With the temperature of hydrothermal treatment exceeding 180 °C, the morphology of hydrothermal sludge became rough which linked closely to the solid precipitation of condensation polymerization, and further became smooth at higher temperature (210 °C) due to the coal-like structures with higher aromaticities, indicating that hydrothermal reaction pathways began to play a main role in enhanced dewaterability. Hydrothermal treatment led to more alkyl and aromatic carbon, but lower O-alkyl, carboxyl and carbonyl carbon. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Pharmacological Profile of Quinoxalinone

    Directory of Open Access Journals (Sweden)

    Youssef Ramli

    2014-01-01

    Full Text Available Quinoxalinone and its derivatives are used in organic synthesis for building natural and designed synthetic compounds and they have been frequently utilized as suitable skeletons for the design of biologically active compound. This review covers updated information on the most active quinoxalinone derivatives that have been reported to show considerable pharmacological actions such as antimicrobial, anti-inflammatory, antidiabetic, antiviral, antitumor, and antitubercular activity. It can act as an important tool for chemists to develop newer quinoxalinone derivatives that may prove to be better agents in terms of efficacy and safety.

  9. Pharmacologic management of obesity.

    Science.gov (United States)

    Kushner, Robert F

    2012-01-01

    Recent discoveries of processes that govern regulation of body weight and energy expenditure have led to development of new anti-obesity pharmacological agents. This article will inform health professionals of new anti-obesity medications that target neuronal systems within the central nervous system (CNS) and peripheral humoral proteins that send signals to the CNS. An emerging theme of new therapies is to use combination medications that are directed toward several targets or leverage existing gastrointestinal satiety hormonal signals. By using combination therapies, it is anticipated that greater weight loss will be achieved compared to monotherapy. Copyright © 2011 Wiley Periodicals, Inc.

  10. Preparation, Characterization, and Enhanced Thermal and Mechanical Properties of Epoxy-Titania Composites

    Science.gov (United States)

    Rubab, Zakya; Siddiqi, Humaira M.; Saeed, Shaukat

    2014-01-01

    This paper presents the synthesis and thermal and mechanical properties of epoxy-titania composites. First, submicron titania particles are prepared via surfactant-free sol-gel method using TiCl4 as precursor. These particles are subsequently used as inorganic fillers (or reinforcement) for thermally cured epoxy polymers. Epoxy-titania composites are prepared via mechanical mixing of titania particles with liquid epoxy resin and subsequently curing the mixture with an aliphatic diamine. The amount of titania particles integrated into epoxy matrix is varied between 2.5 and 10.0 wt.% to investigate the effect of sub-micron titania particles on thermal and mechanical properties of epoxy-titania composites. These composites are characterized by X-ray photoelectron (XPS) spectroscopy, scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric (TG), and mechanical analyses. It is found that sub-micron titania particles significantly enhance the glass transition temperature (>6.7%), thermal oxidative stability (>12.0%), tensile strength (>21.8%), and Young's modulus (>16.8%) of epoxy polymers. Epoxy-titania composites with 5.0 wt.% sub-micron titania particles perform best at elevated temperatures as well as under high stress. PMID:24578638

  11. Enhancement of Mechanical and Thermal Properties of Polylactic Acid/Polycaprolactone Blends by Hydrophilic Nanoclay

    Directory of Open Access Journals (Sweden)

    Chern Chiet Eng

    2013-01-01

    Full Text Available The effects of hydrophilic nanoclay, Nanomer PGV, on mechanical properties of Polylactic Acid (PLA/Polycaprolactone (PCL blends were investigated and compared with hydrophobic clay, Montmorillonite K10. The PLA/PCL/clay composites were prepared by melt intercalation technique and the composites were characterized by X-ray Diffraction (XRD, Fourier Transform Infrared Spectroscopy (FTIR, Thermogravimetric Analysis (TGA, Dynamic Mechanical Analysis (DMA, Scanning Electron Microscopy (SEM, and Transmission Electron Microscopy (TEM. FTIR spectra indicated that formation of hydrogen bond between hydrophilic clay with the matrix. XRD results show that shifting of basal spacing when clay incorporated into polymer matrix. TEM micrographs reveal the formation of agglomerate in the composites. Based on mechanical properties results, addition of clay Nanomer PGV significantly enhances the flexibility of PLA/PCL blends about 136.26%. TGA showed that the presence of clay improve thermal stability of blends. DMA show the addition of clay increase storage modulus and the presence of clay Nanomer PGV slightly shift two Tg of blends become closer suggest that the presence of clay slightly compatibilizer the PLA/PCL blends. SEM micrographs revealed that presence of Nanomer PGV in blends influence the miscibility of the blends. The PLA/PCL blends become more homogeneous and consist of single phase morphology.

  12. Enhancement of electronic and charge transport properties of NiPc by potassium-tetrasulpho group

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Zubair, E-mail: zubairtarar@gmail.com [Low Dimensional Materials Research Centre, Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Sayyad, M.H.; Wahab, F. [Ghulam Ishaq Khan Institute of Engineering Sciences and Technology, Topi 23640 (Pakistan); Sulaiman, Khaulah [Low Dimensional Materials Research Centre, Department of Physics, University of Malaya, 50603 Kuala Lumpur (Malaysia); Shahid, M.; Chaudry, J.A.; Munawar, M.A. [Institute of Chemistry, University of the Punjab, Lahore 54000 (Pakistan); Aziz, Fakhra [Department of Electronics, Jinnah College for Women, University of Peshawar, Peshawar 25120 (Pakistan)

    2013-03-15

    We report significant enhancement in the electronic properties of nickel phthalocyanine (NiPc) by attaching a potassium-tetrasulpho functional group to synthesize its water soluble derivative nickel (II)4,4′,4″,4'″potassium-tetrasulphophthalocyanine (K{sub 4}NiTSPc). To study the potential of this organic compound for electronics applications, Au/K4NiTSPc/Ag diodes have been fabricated and their electronic parameters have been calculated. The mobility and conductivity of the device have been found to be 1.5×10{sup −4} cm{sup 2} V{sup −2} S{sup −1} and 2.5×10{sup −4} Ω{sup −1} cm{sup −1}. The K{sub 4}NiTSPc has shown much better electronic properties as compared to NiPc reported in the literature, which makes it a promising candidate for its potential use in electronics applications.

  13. Graphite Nanoplatelet Modified Epoxy Resin for Carbon Fibre Reinforced Plastics with Enhanced Properties

    Directory of Open Access Journals (Sweden)

    Yan Li

    2017-01-01

    Full Text Available A simple approach to deliver graphene or graphite nanoplatelets (GNPs into carbon fibre reinforced plastic (CFRPs to enhance the multifunctional properties of carbon/epoxy laminates was demonstrated. GNPs improved the typically low interlaminar mechanical, thermal, and electrical properties of CFRPs after direct vacuum infusion of GNP doped resin obtained via in situ exfoliation by three-roll milling (TRM. Compared to high shear mixing or probe ultrasonication, TRM produces higher shear rates and stresses to exfoliate and finely disperse GNP particles within an epoxy matrix. This environmentally friendly and industrial scalable process does not require the use of solvents, additives, or chemical treatments. The flexural modulus and interlaminar shear strength (ILSS of CFRPs was increased by 15% and by 18%, respectively, with the addition of 5 wt.% in situ exfoliated GNP in the doped epoxy resin. Out-of-plane electrical and thermal conductivity, at the same filler content, were, respectively, improved by nearly two orders of magnitude and 50%.

  14. Graphene immobilized enzyme/polyethersulfone mixed matrix membrane: Enhanced antibacterial, permeable and mechanical properties

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Linlin; Wang, Yuanming [School of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou 450001 (China); Zhang, Yatao, E-mail: zhangyatao@zzu.edu.cn [School of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou 450001 (China); UNESCO Centre for Membrane Science and Technology, University of New South Wales, Sydney, NSW 2052 (Australia); Liu, Jindun [School of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou 450001 (China)

    2015-11-15

    Graphical abstract: - Highlights: • Lysozyme was immobilized on the surface of graphene oxide (GO) and reduced GO (RGO). • The novel hybrid membranes based on lysozyme and graphene were fabricated firstly. • These membranes showed good antibacterial and mechanical performance. - Abstract: Enzyme immobilization has been developed to address lots of issues of free enzyme, such as instability, low activity and difficult to retain. In this study, graphene was used as an ideal carrier for lysozyme immobilization, including graphene oxide (GO) immobilized lysozyme (GO-Ly) and chemically reduced graphene oxide (CRGO) immobilized lysozyme (CRGO-Ly). Herein, lysozyme as a bio-antibacterial agent has excellent antibacterial performance and the products of its catalysis are safety and nontoxic. Then the immobilized lysozyme materials were blended into polyethersulfone (PES) casting solution to prepare PES ultrafiltration membrane via phase inversion method. GO and CRGO were characterized by Fourier transform infrared spectroscopy (FTIR), Ultraviolet–visible spectrum (UV), X-ray diffraction (XRD), and transmission electron microscopy (TEM) and the immobilized lysozyme composites were observed by fluorescent microscopy. The results revealed that GO and CRGO were successfully synthesized and lysozyme was immobilized on their surfaces. The morphology, hydrophilicity, mechanical properties, separation properties and antibacterial activity of the hybrid membranes were characterized in detail. The hydrophilicity, water flux and mechanical strength of the hybrid membranes were significantly enhanced after adding the immobilized lysozyme. In the antibacterial experiment, the hybrid membranes exhibited an effective antibacterial performance against Escherichia coli (E. coli).

  15. Enhanced bolometric properties of TiO2-x thin films by thermal annealing

    Science.gov (United States)

    Ashok Kumar Reddy, Y.; Shin, Young Bong; Kang, In-Ku; Lee, Hee Chul; Sreedhara Reddy, P.

    2015-07-01

    The effect of thermal annealing on the bolometric properties of TiO2-x films was investigated. The test-patterned TiO2-x samples were annealed at 300 °C temperature in order to enhance their structural and electrical properties for effective infrared image sensor device applications. The crystallinity was changed from amorphous to rutile/anatase in annealed TiO2-x films. Compared to the as-deposited samples, a decrement of the band gap and a decrease of the electrical resistivity were perceived in annealed samples. We found that the annealed samples show linear current-voltage (I-V) characteristic performance, which implies that ohmic contact was well formed at the interface between the TiO2-x and the Ti electrode. Moreover, the annealed TiO2-x sample had a significantly low 1/f noise parameter (1.21 × 10-13) with a high bolometric parameter (β) value compared to those of the as-deposited samples. As a result, the thermal annealing process can be used to prepare TiO2-x film for a high-performance bolometric device.

  16. Enhanced protective properties and UV stability of epoxy/graphene nanocomposite coating on stainless steel

    Directory of Open Access Journals (Sweden)

    H. Alhumade

    2016-12-01

    Full Text Available Epoxy-Graphene (E/G nanocomposites with different loading of graphene were prepared via in situ prepolymerization and evaluated as protective coating for Stainless Steel 304 (SS304. The prepolymer composites were spin coated on SS304 substrates and thermally cured. Transmission Electron Microscopy (TEM and Scanning Electron Microscopy (SEM were utilized to examine the dispersion of graphene in the epoxy matrix. Epoxy and E/G nanocomposites were characterized using X-ray diffraction (XRD and Fourier Transform Infrared (FTIR techniques and the thermal behavior of the prepared coatings is analyzed using Thermogravimetric analysis (TGA and Differential scanning calorimetry (DSC. The corrosion protection properties of the prepared coatings were evaluated using Electrochemical Impedance Spectroscopy (EIS and Cyclic Voltammetry (CV measurements. In addition to corrosion mitigation properties, the long-term adhesion performance of the coatings was evaluated by measuring the adhesion of the coatings to the SS304 substrate after 60 days of exposure to 3.5 wt% NaCl medium. The effects of graphene loading on the impact resistance, flexibility, and UV stability of the coating are analyzed and discussed. SEM was utilized to evaluate post adhesion and UV stability results. The results indicate that very low graphene loading up to 0.5 wt % significantly enhances the corrosion protection, UV stability, and impact resistance of epoxy coatings.

  17. Enhanced impact properties of cementitious composites reinforced with pultruded flax/polymeric matrix fabric

    Directory of Open Access Journals (Sweden)

    Magdi El-Messiry

    2017-09-01

    Full Text Available Fiber reinforced concrete (FRC has become increasingly applied in civil engineering in the last decades. Natural fiber fabric reinforced cement composites are considered to prevent damage resulting from an impact loading on the cementite plate. Flax woven fabric that has a high energy absorption capability was chosen. To increase the interfacial shear properties, the fabric was pultruded with different matrix properties that affect the strength and toughness of the pultruded fabric. In this study, three fabric structures are used to increase the anchoring of the cement in the fabric. The compressive strength and the impact energy were measured. The results revealed that pultruded fabric reinforced cement composite (PFRC absorbs much more impact energy. PFRC under impact loading has more micro cracks, while plain cement specimen shows brittle failure. The compressive test results of PFRC indicate that flax fiber fabric polymer enhanced compressive strength remarkably. Fiber reinforcement is a very effective in improving the impact resistance of PFRC. The study defines the influence factors that control the energy dissipation of the composite, which are the hardness of the polymer and the fabric cover factor. Significant correlation between impact energy and compressive strength was proved.

  18. Enhancement of antibacterial properties of polyurethanes by chitosan and heparin immobilization

    Science.gov (United States)

    Kara, Filiz; Aksoy, E. Ayse; Yuksekdag, Zehranur; Aksoy, Serpil; Hasirci, Nesrin

    2015-12-01

    Being antibacterial is a required property for the materials used in medical devices and instruments. Polyurethanes (PUs) are one class of polymers widely used in the production of devices that especially come in contact with blood (e.g. heart valves, blood vessels, vascular grafts and catheters). In this study, hexamethylene diisocyanate based polyurethanes (PUh) were synthesized and antibacterial and anti-adhesive properties were added by immobilizing chitosan (CH) and heparin (Hep) on the samples of PUh via a stepwise process. Chemistry and topography of the modified film samples (PUh-CH and PUh-CH-Hep) were examined by Fourier Transform Infrared Spectrophotometry-Attenuated Total Reflectance (FTIR-ATR), Electron Spectroscopy for Chemical Analysis (ESCA) and Atomic Force Microscopy (AFM), and surface free energy (SFE) values after each step were determined by goniometer. PUh-CH and PUh-CH-Hep samples were found to be antibacterial against Staphylococcus aureus (S. aureus) and Staphylococcus epidermidis (S. epidermidis) (both Gram positive) and Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa) (both Gram negative) bacteria, and bacterial adhesion results showed a significant decrease in the number of viable bacteria on both modified samples where PUh-CH-Hep was the most effective. The findings of this study show that polymeric surfaces can be effectively modified and converted to be antibacterial by chitosan and heparin immobilization, and presence of both chemicals enhance efficacy against bacteria.

  19. Graphene immobilized enzyme/polyethersulfone mixed matrix membrane: Enhanced antibacterial, permeable and mechanical properties

    Science.gov (United States)

    Duan, Linlin; Wang, Yuanming; Zhang, Yatao; Liu, Jindun

    2015-11-01

    Enzyme immobilization has been developed to address lots of issues of free enzyme, such as instability, low activity and difficult to retain. In this study, graphene was used as an ideal carrier for lysozyme immobilization, including graphene oxide (GO) immobilized lysozyme (GO-Ly) and chemically reduced graphene oxide (CRGO) immobilized lysozyme (CRGO-Ly). Herein, lysozyme as a bio-antibacterial agent has excellent antibacterial performance and the products of its catalysis are safety and nontoxic. Then the immobilized lysozyme materials were blended into polyethersulfone (PES) casting solution to prepare PES ultrafiltration membrane via phase inversion method. GO and CRGO were characterized by Fourier transform infrared spectroscopy (FTIR), Ultraviolet-visible spectrum (UV), X-ray diffraction (XRD), and transmission electron microscopy (TEM) and the immobilized lysozyme composites were observed by fluorescent microscopy. The results revealed that GO and CRGO were successfully synthesized and lysozyme was immobilized on their surfaces. The morphology, hydrophilicity, mechanical properties, separation properties and antibacterial activity of the hybrid membranes were characterized in detail. The hydrophilicity, water flux and mechanical strength of the hybrid membranes were significantly enhanced after adding the immobilized lysozyme. In the antibacterial experiment, the hybrid membranes exhibited an effective antibacterial performance against Escherichia coli (E. coli).

  20. Pyrene-Phosphonate Conjugate: Aggregation-Induced Enhanced Emission, and Selective Fe3+Ions Sensing Properties.

    Science.gov (United States)

    Padghan, Sachin D; Bhosale, Rajesh S; Bhosale, Sidhanath V; Antolasic, Frank; Al Kobaisi, Mohammad; Bhosale, Sheshanath V

    2017-08-29

    A new pyrene-phosphonate colorimetric receptor 1 has been designed and synthesized in a one-step process via amide bond formation between pyrene butyric acid chloride and phosphonate-appended aniline. The pyrene-phosphonate receptor 1 showed aggregation-induced enhanced emission (AIEE) properties in water/acetonitrile (ACN) solutions. Dynamic light scattering (DLS) characterization revealed that the aggregates of receptor 1 at 80% water fraction have an average size of ≈142 nm. Field emission scanning electron microscopy (FE-SEM) analysis confirmed the formation of spherical aggregates upon solvent evaporation. The sensing properties of receptor 1 were investigated by UV-vis, fluorescence emission spectroscopy, and other optical methods. Among the tested metal ions, receptor 1 is capable of recognizing the Fe 3+ ion selectively. The changes in spectral measurements were explained on the basis of complex formation. The composition of receptor 1 and Fe 3+ ions was determined by using Job's plot and found to be 1:1. The receptor 1 -Fe 3 + complex showed a reversible UV-vis response in the presence of EDTA.

  1. Enhanced photoelectrochemical properties of copper-assisted catalyzed etching black silicon by electrodepositing cobalt

    Science.gov (United States)

    Cai, Weidong; Xiong, Haiying; Su, Xiaodong; Zhou, Hao; Shen, Mingrong; Fang, Liang

    2017-11-01

    Black silicon (Si) photoelectrodes are promising for improving the performance of photoelectrochemical (PEC) water splitting. Here, we report the fabrication of p-black Si and n+p-black Si photocathodes via a controllable copper-assisted catalyzed etching method. The etching process affects only the topmost less than 200 nm of Si and is independent of the surface doping. The synergistic effects of the excellent light harvesting of the black Si and the improved charge transfer properties of the p-n junction boost the production and utilization of photogenerated carriers. The mean reflectance of the pristine Si samples is about 10% from 400 to 950 nm, while that of the black Si samples is reduced as low as 5%. In addition, the PEC properties of the n+p-black Si photocathode can be further enhanced by depositing a cobalt (Co) layer. Compared with the p-Si sample, the onset potential of the Co/n+p-black Si photocathode is positively shifted by 560 mV to 0.33 V vs. reversible hydrogen electrode and the saturation photocurrent density is increased from 22.7 to 32.6 mA/cm2. The design of the Co/n+p-black Si photocathode offers an efficient strategy for preparing PEC solar energy conversion devices.

  2. Polyaniline/carbon nanotube/CdS quantum dot composites with enhanced optical and electrical properties

    Energy Technology Data Exchange (ETDEWEB)

    Goswami, Mrinmoy [Department of Physics, National Institute of Technology, Durgapur, 713209 (India); Ghosh, Ranajit, E-mail: ghosh.ranajit@gmail.com [CSIR-Central Mechanical Engineering Research Institute, Durgapur, 713209 (India); Maruyama, Takahiro [Department of Applied Chemistry, Meijo University, Nagoya, 4688502 (Japan); Meikap, Ajit Kumar [Department of Physics, National Institute of Technology, Durgapur, 713209 (India)

    2016-02-28

    Graphical abstract: - Highlights: • A new kind of polyaniline/carbon nanotube/CdS quantum dot composites have been synthesized via in-situ polymerization of aniline monomer. • A degree of increase in conductivity. • Size-dependent optical properties of CdS quantum dots have been observed. - Abstract: A new kind of polyaniline/carbon nanotube/CdS quantum dot composites have been developed via in-situ polymerization of aniline monomer in the presence of dispersed CdS quantum dots (size: 2.7–4.8 nm) and multi-walled carbon nanotubes (CNT), which exhibits enhanced optical and electrical properties. The existences of 1st order, 2nd order, and 3rd order longitudinal optical phonon modes, strongly indicate the high quality of synthesized CdS quantum dots. The occurrence of red shift of free exciton energy in photoluminescence is due to size dependent quantum confinement effect of CdS. The conductivity of the composites (for example PANI/CNT/CdS (2 wt.% CdS)) is increased by about 7 of magnitude compared to that of pure PANI indicating a charge transfer between CNT and polymer via CdS quantum dots. This advanced material has a great potential for high-performance of electro-optical applications.

  3. Enhanced photoelectrochemical properties of TiO2 by codoping with tungsten and silver

    Science.gov (United States)

    Khan, Matiullah; Jiang, Peng; Li, Jing; Cao, Wenbin

    2014-04-01

    The Tungsten (W) and Silver (Ag) codoped TiO2 samples were successfully synthesized by hydrothermal method without any post calcination. To understand the correlation between electronic structure and photocatalytic properties, the synthesized samples were characterized using X-ray diffraction, Brunauer-Emmett-Teller specific surface area, transmission electron microscopy, ultra-violet-visible absorption spectra, and X-ray photoelectron spectroscopy (XPS), and the photocatalytic properties were evaluated under visible light irradiations. Codoping could not induce any changes in the phase and all the synthesized samples displayed pure anatase phase with spherical morphology. Visible light absorptions of the codoped samples were dramatically improved compared to the corresponding mono-doped samples. XPS analysis indicated that the dopant atoms successfully entered the TiO2 network. Results from the visible light photodegradation experiments showed that tungsten-silver codoped TiO2 possessed strong ability in photo-degrading methylene blue compared to tungsten doped TiO2 and silver doped TiO2, which was attributed to the smaller particle size, higher specific surface area, enhanced visible light absorption, and improved separation of photogenerated carriers.

  4. Development of Chitosan Scaffolds with Enhanced Mechanical Properties for Intestinal Tissue Engineering Applications.

    Science.gov (United States)

    Zakhem, Elie; Bitar, Khalil N

    2015-10-13

    Massive resections of segments of the gastrointestinal (GI) tract lead to intestinal discontinuity. Functional tubular replacements are needed. Different scaffolds were designed for intestinal tissue engineering application. However, none of the studies have evaluated the mechanical properties of the scaffolds. We have previously shown the biocompatibility of chitosan as a natural material in intestinal tissue engineering. Our scaffolds demonstrated weak mechanical properties. In this study, we enhanced the mechanical strength of the scaffolds with the use of chitosan fibers. Chitosan fibers were circumferentially-aligned around the tubular chitosan scaffolds either from the luminal side or from the outer side or both. Tensile strength, tensile strain, and Young's modulus were significantly increased in the scaffolds with fibers when compared with scaffolds without fibers. Burst pressure was also increased. The biocompatibility of the scaffolds was maintained as demonstrated by the adhesion of smooth muscle cells around the different kinds of scaffolds. The chitosan scaffolds with fibers provided a better candidate for intestinal tissue engineering. The novelty of this study was in the design of the fibers in a specific alignment and their incorporation within the scaffolds.

  5. Electrical transport properties of graphene nanowalls grown at low temperature using plasma enhanced chemical vapor deposition

    Science.gov (United States)

    Zhao, Rong; Ahktar, Meysam; Alruqi, Adel; Dharmasena, Ruchira; Jasinski, Jacek B.; Thantirige, Rukshan M.; Sumanasekera, Gamini U.

    2017-05-01

    In this work, we report the electrical transport properties of uniform and vertically oriented graphene (graphene nanowalls) directly synthesized on multiple substrates including glass, Si/SiO2 wafers, and copper foils using radio-frequency plasma enhanced chemical vapor deposition (PECVD) with methane (CH4) as the precursor at relatively low temperatures. The temperature for optimum growth was established with the aid of transmission electron microscopy, scanning electron microscopy, and Raman spectroscopy. This approach offers means for low-cost graphene nanowalls growth on an arbitrary substrate with the added advantage of transfer-free device fabrication. The temperature dependence of the electrical transport properties (resistivity and thermopower) were studied in the temperature range, 30-300 K and analyzed with a combination of 2D-variable range hopping (VRH) and thermally activated (TA) conduction mechanisms. An anomalous temperature dependence of the thermopower was observed for all the samples and explained with a combination of a diffusion term having a linear temperature dependence plus a term with an inverse temperature dependence.

  6. Enhanced Microbial, Functional and Sensory Properties of Herbal Yogurt Fermented with Korean Traditional Plant Extracts

    Science.gov (United States)

    Joung, Jae Yeon; Lee, Ji Young; Ha, Young Sik; Shin, Yong Kook; Kim, Younghoon; Kim, Sae Hun; Oh, Nam Su

    2016-01-01

    This study evaluated the effects of two Korean traditional plant extracts (Diospyros kaki THUNB. leaf; DK, and Nelumbo nucifera leaf; NN) on the fermentation, functional and sensory properties of herbal yogurts. Compared to control fermentation, all plant extracts increased acidification rate and reduced the time to complete fermentation (pH 4.5). Supplementation of plant extracts and storage time were found to influence the characteristics of the yogurts, contributing to increased viability of starter culture and phenolic compounds. In particular, the increase in the counts of Streptococcus thermophilus and Lactobacillus delbrueckii subsp. bulgaricus was highest (2.95 and 1.14 Log CFU/mL respectively) in DK yogurt. Furthermore, supplementation of the plant extracts significantly influenced to increase the antioxidant activity and water holding capacity and to produce volatile compounds. The higher antioxidant activity and water holding capacity were observed in NN yogurt than DK yogurt. Moreover, all of the sensory characteristics were altered by the addition of plant extracts. Addition of plant extracts increased the scores related to flavor, taste, and texture from plain yogurt without a plant extract, as a result of volatile compounds analysis. Thus, the overall preference was increased by plant extracts. Consequently, supplementation of DK and NN extracts in yogurt enhanced the antioxidant activity and physical property, moreover increased the acceptability of yogurt. These findings demonstrate the possibility of using plant extracts as a functional ingredient in the manufacture of herbal yogurt. PMID:27499669

  7. Enhancement in the microstructure and photoluminescence properties of YVO4:Eu3+ by Al doping.

    Science.gov (United States)

    Shin, Pyeong Ji; Balakrishnaiah, R; Yi, Soung Soo; Jang, Kiwan; Lee, Ho Sueb; Shin, Dong-Soo; Jeong, Jung Hyun

    2013-08-01

    Al contents have been doped as a sensitizer to improve the luminescent brightness, and the conventional solid state reaction method has been used to synthesize the phosphors. Al doping effects on the microstructures of YVO4:Eu3+ phosphors were measured by X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). The luminescent characteristics were characterized by photoluminescence excitation (PLE) and emission (PL) measurements. Incorporation of Al3+ ions into the YVO4:Eu phosphors has greatly enhanced the crystallinity, particle size and hence the luminescence properties and the optimum concentration in Al dopants are found to be 0.05 mol. The photoluminescence intensity of 0.05 mol Al(3+)-doped YVO4:Eu3+ phosphors was improved by a factor of 1.41, in comparison with undoped Y0.95Eu0.05VO4 phosphor. The improvement in photoluminescence properties with Al doping may result from the improved crystallinity and from the enlarged grain sizes inducing lower scattering loss.

  8. Temperature-Induced Lattice Relaxation of Perovskite Crystal Enhances Optoelectronic Properties and Solar Cell Performance

    KAUST Repository

    Banavoth, Murali

    2016-12-14

    Hybrid organic-inorganic perovskite crystals have recently become one of the most important classes of photoactive materials in the solar cell and optoelectronic communities. Albeit improvements have focused on state-of-the-art technology including various fabrication methods, device architectures, and surface passivation, progress is yet to be made in understanding the actual operational temperature on the electronic properties and the device performances. Therefore, the substantial effect of temperature on the optoelectronic properties, charge separation, charge recombination dynamics, and photoconversion efficiency are explored. The results clearly demonstrated a significant enhancement in the carrier mobility, photocurrent, charge carrier lifetime, and solar cell performance in the 60 ± 5 °C temperature range. In this temperature range, perovskite crystal exhibits a highly symmetrical relaxed cubic structure with well-aligned domains that are perpendicular to a principal axis, thereby remarkably improving the device operation. This finding provides a new key variable component and paves the way toward using perovskite crystals in highly efficient photovoltaic cells.

  9. Enhanced production of bacterial cellulose by using a biofilm reactor and its material property analysis

    Directory of Open Access Journals (Sweden)

    Demirci Ali

    2009-07-01

    Full Text Available Abstract Bacterial cellulose has been used in the food industry for applications such as low-calorie desserts, salads, and fabricated foods. It has also been used in the paper manufacturing industry to enhance paper strength, the electronics industry in acoustic diaphragms for audio speakers, the pharmaceutical industry as filtration membranes, and in the medical field as wound dressing and artificial skin material. In this study, different types of plastic composite support (PCS were implemented separately within a fermentation medium in order to enhance bacterial cellulose (BC production by Acetobacter xylinum. The optimal composition of nutritious compounds in PCS was chosen based on the amount of BC produced. The selected PCS was implemented within a bioreactor to examine the effects on BC production in a batch fermentation. The produced BC was analyzed using X-ray diffraction (XRD, field emission scanning electron microscopy (FESEM, thermogravimetric analysis (TGA, and dynamic mechanical analysis (DMA. Among thirteen types of PCS, the type SFYR+ was selected as solid support for BC production by A. xylinum in a batch biofilm reactor due to its high nitrogen content, moderate nitrogen leaching rate, and sufficient biomass attached on PCS. The PCS biofilm reactor yielded BC production (7.05 g/L that was 2.5-fold greater than the control (2.82 g/L. The XRD results indicated that the PCS-grown BC exhibited higher crystallinity (93% and similar crystal size (5.2 nm to the control. FESEM results showed the attachment of A. xylinum on PCS, producing an interweaving BC product. TGA results demonstrated that PCS-grown BC had about 95% water retention ability, which was lower than BC produced within suspended-cell reactor. PCS-grown BC also exhibited higher Tmax compared to the control. Finally, DMA results showed that BC from the PCS biofilm reactor increased its mechanical property values, i.e., stress at break and Young's modulus when compared to

  10. Ambient redox synthesis of vanadium-doped manganese dioxide nanoparticles and their enhanced zinc storage properties

    Energy Technology Data Exchange (ETDEWEB)

    Alfaruqi, Muhammad Hilmy; Islam, Saiful; Mathew, Vinod; Song, Jinju; Kim, Sungjin; Tung, Duong Pham; Jo, Jeonggeun; Kim, Seokhun; Baboo, Joseph Paul; Xiu, Zhiliang; Kim, Jaekook, E-mail: jaekook@chonnam.ac.kr

    2017-05-15

    Highlights: • The V-doped MnO{sub 2} was prepared by a simple ambient redox reaction. • The V-doped MnO{sub 2} was tested as a cathode in aqueous zinc-ion batteries (ZIBs). • The doped cathode showed better zinc-storage properties than the bare cathode. • The present study facilitates the development of safe and reliable aqueous ZIBs. - Abstract: In this work, we demonstrate the first use of a V-doped MnO{sub 2} nanoparticle electrode for zinc-ion battery (ZIB) applications. The V-doped MnO{sub 2} was prepared via a simple redox reaction and the X-ray diffraction studies confirmed the formation of pure MnO{sub 2}, accompanied by an anisotropic expansion of MnO{sub 2} lattice, suggesting the incorporation of V-ions into the MnO{sub 2} framework. V doping of MnO{sub 2} not only increased the specific surface area but also improved the electronic conductivity. When Zn-storage properties were tested, the V-doped MnO{sub 2} electrode registered a higher discharge capacity of 266 mAh g{sup −1} compared to 213 mAh g{sup −1} for the pure MnO{sub 2} electrode. On prolonged cycling, the doped electrode retained 31% higher capacity than that of the bare MnO{sub 2} electrode and thereby demonstrated superior cycling performance. This study may pave the way towards understanding the enhancement of the energy storage properties via doping in electrodes of aqueous ZIB applications and also furthers the efforts for the practical realization of a potential eco-friendly battery system.

  11. Bioabsorbable bypass grafts biofunctionalised with RGD have enhanced biophysical properties and endothelialisation tested in vivo

    Directory of Open Access Journals (Sweden)

    Larisa V Antonova

    2016-05-01

    Full Text Available Small diameter arterial bypass grafts are considered as unmet clinical need since the current grafts have poor patency of 25% within 5 years. We have developed a 3D scaffold manufactured from natural and synthetic biodegradable polymers, poly(3-hydroxybutyrate-co-3-hydroxyvalerate (PHBV and poly(ε-caprolactone (PCL, respectively. Further to improve the biophysical properties as well as endothelialisation, the grafts were covalently conjugated with arginine-glycine-aspartic acid (RGD bioactive peptides. The biophysical properties as well as endothelialisation of PHBV/PCL and PCL 2 mm diameter bypass grafts were assessed with and without biofunctionalisation with RGD peptides in vitro and in vivo. Morphology of the grafts was assessed by scanning electron microscopy, whereas physico-mechanical properties were evaluated using a physiological circulating system equipped with a state of art ultrasound vascular wall tracking system. Endothelialisation of the grafts in vitro and in vivo were assessed using a cell viability assay and rat abdominal aorta replacement model, respectively. The biofunctionalisation with RGD bioactive peptides decreased mean fiber diameter and mean pore area in PHBV/PCL grafts; however, this was not the case for PCL grafts. Both PHBV/PCL and PCL grafts with RGD peptides had lower durability compared to those without; these durability values were similar to those of internal mammary artery. Modification of PHBV/PCL and PCL grafts with RGD peptides increased endothelial cell viability in vitro by a factor of 8 and enhanced the formation of an endothelial cell monolayer in vivo one month postimplantation. In conclusion, PHBV/PCL small-caliber graft can be a suitable 3D scaffold for the development of a tissue engineering arterial bypass graft.

  12. Creating a virtual pharmacology curriculum in a problem-based learning environment: one medical school's experience.

    Science.gov (United States)

    Karpa, Kelly Dowhower; Vrana, Kent E

    2013-02-01

    Integrating pharmacology education into a problem-based learning (PBL) curriculum has proven challenging for many medical schools, including the Pennsylvania State University College of Medicine (Penn State COM). In response to pharmacology content gaps in its PBL-intensive curriculum, Penn State COM in 2003 hired a director of medical pharmacology instruction to oversee efforts to improve the structure of pharmacology education in the absence of a stand-alone course. In this article, the authors describe the ongoing development of the virtual pharmacology curriculum, which weaves pharmacology instruction through the entire medical school curriculum with particular emphasis on the organ-based second year. Pharmacology is taught in a spiraling manner designed to add to and build upon students' knowledge and competency. Key aspects of the virtual curriculum (as of 2011) include clearly stated and behaviorally oriented pharmacology learning objectives, pharmacology study guides that correspond to each PBL case, pharmacology review sessions that feature discussions of United States Medical Licensing Examination (USMLE)-type questions, and pharmacology questions for each PBL case on course examinations to increase student accountability. The authors report a trend toward improved USMLE Step 1 scores since these initiatives were introduced. Furthermore, graduates' ratings of their pharmacology education have improved on the Medical School Graduation Questionnaire. The authors suggest that the initiatives they describe for enhancing pharmacology medical education are relevant to other medical schools that are also seeking ways to better integrate pharmacology into PBL-based curricula.

  13. Epigenetics and pharmacology

    Science.gov (United States)

    Stefanska, Barbara; MacEwan, David J

    2015-01-01

    Recent advances in the understanding of gene regulation have shown there to be much more regulation of the genome than first thought, through epigenetic mechanisms. These epigenetic mechanisms are systems that have evolved to either switch off gene activity altogether, or fine-tune any existing genetic activation. Such systems are present in all genes and include chromatin modifications and remodelling, DNA methylation (such as CpG island methylation rates) and histone covalent modifications (e.g. acetylation, methylation), RNA interference by short interfering RNAs (siRNAs) and long non-coding RNAs (ncRNAs). These systems regulate genomic activity ‘beyond’ simple transcriptional factor inducer or repressor function of genes to generate mRNA. Epigenetic regulation of gene activity has been shown to be important in maintaining normal phenotypic activity of cells, as well as having a role in development and diseases such as cancer and neurodegenerative disorders such as Alzheimer's. Newer classes of drugs regulate epigenetic mechanisms to counteract disease states in humans. The reports in this issue describe some advances in epigenetic understanding that relate to human disease, and our ability to control these mechanisms by pharmacological means. Increasingly the importance of epigenetics is being uncovered – it is pharmacology that will have to keep pace. PMID:25966315

  14. Pharmacological properties of cashew (Anacardium occidentale)

    African Journals Online (AJOL)

    Rai Pablo Sousa de Aguiar

    2016-08-31

    Aug 31, 2016 ... Anacardium occidentale L. is a tree native to Brazil, which is rich in phenolic lipids. Nowadays, the cashew bark (Cashew Nut Shell Liquid) has received great attention in the pharmaceutical industry, due to its economy, abundance and important chemical compounds. Net of cashew nut shell is classified.

  15. Therapeutic potentials and pharmacological properties of Moringa ...

    African Journals Online (AJOL)

    Plants have played a vital role in ... Moringa oleifera (MO) is one of such plants which have been used for centuries as a ... cosmetics, dyes, fertilizers and water purification. ... reactive oxygen species (ROS) and inflammatory .... food of the indigenes of Ethiopia, pygmaea, .... Also, ethanolic and freeze dried leaves extract of.

  16. Lactoferrin from Milk: Nutraceutical and Pharmacological Properties

    Directory of Open Access Journals (Sweden)

    Francesco Giansanti

    2016-09-01

    Full Text Available Lactoferrin is an iron-binding protein present in large quantities in colostrum and in breast milk, in external secretions and in polymorphonuclear leukocytes. Lactoferrin’s main function is non-immune protection. Among several protective activities shown by lactoferrin, those displayed by orally administered lactoferrin are: (i antimicrobial activity, which has been presumed due to iron deprivation, but more recently attributed also to a specific interaction with the bacterial cell wall and extended to viruses and parasites; (ii immunomodulatory activity, with a direct effect on the development of the immune system in the newborn, together with a specific antinflammatory effects; (iii a more recently discovered anticancer activity. It is worth noting that most of the protective activities of lactoferrin have been found, sometimes to a greater extent, also in peptides derived from limited proteolysis of lactoferrin that could be generated after lactoferrin ingestion. Lactoferrin could therefore be considered an ideal nutraceutic product because of its relatively cheap production from bovine milk and of its widely recognized tolerance after ingestion, along with its well demonstrated protective activities. The most important protective activities shown by orally administered bovine lactoferrin are reviewed in this article.

  17. Phytochemical and Pharmacological Properties of the Genus ...

    African Journals Online (AJOL)

    Melodinus is an important genus comprising of approximately 53 species of medicinal plants (Apocynaceae). Some species have been used in Chinese folk medicine for the treatment of meningitis in children, rheumatic heart diseases, and diuresis, as well as a decongestive against migraine and sinusitis. This paper is a ...

  18. Therapeutic potentials and pharmacological properties of Moringa ...

    African Journals Online (AJOL)

    gum), water purification (seeds) [29]. The oil extracted from MO seed known as Ben oil, is a sweet non-sticking and non-drying oil that resists rancidity [41]. People in many developing countries, especially in Africa have been using Moringa oleifera to treat and manage the symptoms of diabetes for years. The International ...

  19. In-situ plasma hydrogenated TiO{sub 2} thin films for enhanced photoelectrochemical properties

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Aadesh P.; Kodan, Nisha [Thin Film Laboratory, Department of Physics, Indian Institute of Technology, Hauz Khas, New Delhi 110016 (India); Mehta, Bodh R., E-mail: brmehta@physics.iitd.ac.in [Thin Film Laboratory, Department of Physics, Indian Institute of Technology, Hauz Khas, New Delhi 110016 (India); Dey, Avishek; Krishnamurthy, Satheesh [Materials Engineering, The Open University, Milton Keynes, MK7 6AA (United Kingdom)

    2016-04-15

    Highlights: • Growth of TiO{sub 2} thin films with in-situ plasma hydrogenation. • Presence of Ti{sup 2+} states in addition to Ti{sup 3+} states present in pristine TiO{sub 2}. • Change in VBM, work function and band gap in iH:TiO{sub 2}. • Enhanced photocurrent density as compared to pristine TiO{sub 2} films. - Abstract: In this paper, we report the effect of in-situ plasma hydrogenation of TiO{sub 2} (iH:TiO{sub 2}) thin films by the incorporation of known amount of hydrogen in the Ar plasma during rf-sputter deposition of TiO{sub 2} films. As compared to pristine TiO{sub 2} films (∼0.43 mA/cm2 at 0.23 V vs Ag/AgCl), hydrogenated TiO{sub 2} showed enhanced photoelectrochemical activity in terms of improved photocurrent density of ∼1.08 mA/cm2 (at 0.23 V vs Ag/AgCl). These results are explained in terms of reduction in band gap energy, shift in valence band maximum away from the Fermi level, improved donor density and more negative flat band potential in iH:TiO{sub 2} sample. The presence of Ti{sup 2+} states in iH:TiO{sub 2} films in addition to Ti{sup 3+} states in pristine TiO{sub 2} act as additional electronic states in the TiO{sub 2} band gap and increases the optical absorption in the visible region. This method of in-situ hydrogenation can be used as a general method for improving the properties of metal oxide thin films for photoelectrochemical and photocatalytic applications.

  20. Pharmacological therapy for amblyopia

    Science.gov (United States)

    Singh, Anupam; Nagpal, Ritu; Mittal, Sanjeev Kumar; Bahuguna, Chirag; Kumar, Prashant

    2017-01-01

    Amblyopia is the most common cause of preventable blindness in children and young adults. Most of the amblyopic visual loss is reversible if detected and treated at appropriate time. It affects 1.0 to 5.0% of the general population. Various treatment modalities have been tried like refractive correction, patching (both full time and part time), penalization and pharmacological therapy. Refractive correction alone improves visual acuity in one third of patients with anisometropic amblyopia. Various drugs have also been tried of which carbidopa & levodopa have been popular. Most of these agents are still in experimental stage, though levodopa-carbidopa combination therapy has been widely studied in human amblyopes with good outcomes. Levodopa therapy may be considered in cases with residual amblyopia, although occlusion therapy remains the initial treatment choice. Regression of effect after stoppage of therapy remains a concern. Further studies are therefore needed to evaluate the full efficacy and side effect profile of these agents. PMID:29018759

  1. Enhancement of antibacterial properties of polyurethanes by chitosan and heparin immobilization

    Energy Technology Data Exchange (ETDEWEB)

    Kara, Filiz [Department of Chemistry, Faculty of Science, Gazi University, 06500 Ankara (Turkey); Aksoy, E. Ayse [Department of Basic Pharmaceutical Sciences, Faculty of Pharmacy, Hacettepe University, 06100 Ankara (Turkey); Yuksekdag, Zehranur [Biotechnology Laboratory, Department of Biology, Faculty of Science, Gazi University, 06500 Ankara (Turkey); Aksoy, Serpil [Department of Chemistry, Faculty of Science, Gazi University, 06500 Ankara (Turkey); Hasirci, Nesrin, E-mail: nhasirci@metu.edu.tr [BIOMATEN, Center of Excellence in Biomaterials and Tissue Engineering, Middle East Technical University, 06800 Ankara (Turkey); Department of Chemistry, Faculty of Arts and Sciences, Middle East Technical University, 06800 Ankara (Turkey)

    2015-12-01

    Graphical abstract: - Highlights: • Polyurethane elastomer was synthesized in medical purity. • Chitosan (CH) and heparin (Hep) were immobilized on polyurethane films. • Modification with CH and Hep increased hydrophilicity and surface free energy. • Immobilized films had high antibacterial activity against four bacteria. • Bacterial adhesion significantly decreased on the modified surfaces. - Abstract: Being antibacterial is a required property for the materials used in medical devices and instruments. Polyurethanes (PUs) are one class of polymers widely used in the production of devices that especially come in contact with blood (e.g. heart valves, blood vessels, vascular grafts and catheters). In this study, hexamethylene diisocyanate based polyurethanes (PUh) were synthesized and antibacterial and anti-adhesive properties were added by immobilizing chitosan (CH) and heparin (Hep) on the samples of PUh via a stepwise process. Chemistry and topography of the modified film samples (PUh-CH and PUh-CH-Hep) were examined by Fourier Transform Infrared Spectrophotometry-Attenuated Total Reflectance (FTIR-ATR), Electron Spectroscopy for Chemical Analysis (ESCA) and Atomic Force Microscopy (AFM), and surface free energy (SFE) values after each step were determined by goniometer. PUh-CH and PUh-CH-Hep samples were found to be antibacterial against Staphylococcus aureus (S. aureus) and Staphylococcus epidermidis (S. epidermidis) (both Gram positive) and Escherichia coli (E. coli) and Pseudomonas aeruginosa (P. aeruginosa) (both Gram negative) bacteria, and bacterial adhesion results showed a significant decrease in the number of viable bacteria on both modified samples where PUh-CH-Hep was the most effective. The findings of this study show that polymeric surfaces can be effectively modified and converted to be antibacterial by chitosan and heparin immobilization, and presence of both chemicals enhance efficacy against bacteria.

  2. Effects of particle shape and size on nanofluid properties for potential Enhanced Oil Recovery (EOR

    Directory of Open Access Journals (Sweden)

    Tengku Mohd Tengku Amran

    2016-01-01

    Full Text Available Application of Enhanced Oil Recovery (EOR in oil and gas industry is very important to increase oil recovery and prolong the lifetime of a reservoir but it has been very costly and losing properties of EOR agent due to harsh condition. Nanoparticles have been used in EOR application since they are not degradable in reservoir condition and used in smaller amount compared to polymer usage. Commonly, EOR techniques are focusing on increasing the sweep efficiency by controlling the mobility ratio between reservoir fluid and injected fluid. Thus, this research aimed to analyze the nanofluid viscosity at different particle size and shape, volumetric concentration and types of dispersing fluid, as well as to determine the oil recovery performance at different nanofluid concentration. The nanofluid viscosity was investigated at nanoparticle sizes of 15nm and 60nm and shapes of 15nm spherical-solid and porous. Five nanofluid samples with concentration ranging from 0.1wt.% to 7wt.% were used to investigate the effect of volumetric concentration. Distilled water, ethanol, ethylene glycol (EG and brine were used for the effect of dispersing fluids. Oil recovery was investigated at five different concentrations of nanofluid samples through flooding test. It was found that viscosity of nanofluid increased with decreasing particle size and increasing volumetric concentration. Solid shape particle and increasing dispersing fluid viscosity resulted in higher nanofluid viscosity. The higher the nanofluid concentration, the higher the oil recovery obtained. It can be concluded that nanofluid properties have been significantly affected by the environment and the particle used for potential EOR application.

  3. Using The Corngrass1 Gene To Enhance The Biofuel Properties Of Crop Plants

    Energy Technology Data Exchange (ETDEWEB)

    Hake, Sarah [USDA Agricultural Research Service, Washington DC (United States); Chuck, George [USDA Agricultural Research Service, Washington DC (United States)

    2015-10-29

    The development of novel plant germplasm is vital to addressing our increasing bioenergy demands. The major hurdle to digesting plant biomass is the complex structure of the cell walls, the substrate of fermentation. Plant cell walls are inaccessible matrices of macromolecules that are polymerized with lignin, making fermentation difficult. Overcoming this hurdle is a major goal toward developing usable bioenergy crop plants. Our project seeks to enhance the biofuel properties of perennial grass species using the Corngrass1 (Cg1) gene and its targets. Dominant maize Cg1 mutants produce increased biomass by continuously initiating extra axillary meristems and leaves. We cloned Cg1 and showed that its phenotype is caused by over expression of a unique miR156 microRNA gene that negatively regulates SPL transcription factors. We transferred the Cg1 phenotype to other plants by expressing the gene behind constitutive promoters in four different species, including the monocots, Brachypodium and switchgrass, and dicots, Arabidopsis and poplar. All transformants displayed a similar range of phenotypes, including increased biomass from extended leaf production, and increased vegetative branching. Field grown switchgrass transformants showed that overall lignin content was reduced, the ratio of glucans to xylans was increased, and surprisingly, that starch levels were greatly increased. The goals of this project are to control the tissue and temporal expression of Cg1 by using different promoters to drive its expression, elucidate the function of the SPL targets of Cg1 by generating gain and loss of function alleles, and isolate downstream targets of select SPL genes using deep sequencing and chromatin immunoprecipitation. We believe it is possible to control biomass accumulation, cell wall properties, and sugar levels through manipulation of either the Cg1 gene and/or its SPL targets.

  4. Improving pharmacological targeting of AKT in melanoma.

    Science.gov (United States)

    Kuzu, Omer F; Gowda, Raghavendra; Sharma, Arati; Noory, Mohammad A; Dinavahi, Saketh S; Kardos, Gregory; Drabick, Joseph J; Robertson, Gavin P

    2017-09-28

    Targeting AKT with pharmacological agents inhibiting this protein in the melanoma clinic is ineffective. This is a major contradiction considering the substantial preclinical data suggesting AKT as an effective target. Various approaches have been undertaken to unravel this contradiction and drug combinations sought that could resolve this concern. We have shown that genetic targeting AKT3 or WEE1 can be effective for inhibiting tumor growth in preclinical animal models. However, no one has examined whether combining pharmacological agents targeting each of these enzymes could be more effective than inhibiting each alone and enhance the efficacy of targeting AKT in melanoma. This report shows that combining the AKT inhibitors (AZD5363 or MK1775) with the WEE1 inhibitor, AZD5363, can synergistically kill cultured melanoma cells and decrease melanoma tumor growth by greater than 90%. Co-targeting AKT and WEE1 led to enhanced deregulation of the cell cycle and DNA damage repair pathways by modulating the transcription factors p53 and FOXM1, as well as the proteins whose expression is regulated by these two proteins. Thus, this study identifies a unique combination of pharmacological agents and the ratio needed for efficacy that could be used to potentially improve the therapeutic effectiveness of targeting AKT in the clinic. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Enhanced mechanical properties and increased corrosion resistance of a biodegradable magnesium alloy by plasma electrolytic oxidation (PEO).

    Science.gov (United States)

    White, Leon; Koo, Youngmi; Neralla, Sudheer; Sankar, Jagannathan; Yun, Yeoheung

    2016-06-01

    We report the enhanced mechanical properties of AZ31 magnesium alloys by plasma electrolytic oxidation (PEO) coating in NaOH, Na2SiO3, KF and NaH2PO4·2H2O containing electrolytes. Mechanical properties including wear resistance, surface hardness and elastic modulus were increased for PEO-coated AZ31 Mg alloys (PEO-AZ31). DC polarization in Hank's solution indicating that the corrosion resistance significantly increased for PEO-coating in KF-contained electrolyte. Based on these results, the PEO coating method shows promising potential for use in biodegradable implant applications where tunable corrosion and mechanical properties are needed.

  6. A shape memory foam composite with enhanced fluid uptake and bactericidal properties as a hemostatic agent.

    Science.gov (United States)

    Landsman, T L; Touchet, T; Hasan, S M; Smith, C; Russell, B; Rivera, J; Maitland, D J; Cosgriff-Hernandez, E

    2017-01-01

    Uncontrolled hemorrhage accounts for more than 30% of trauma deaths worldwide. Current hemostatic devices focus primarily on time to hemostasis, but prevention of bacterial infection is also critical for improving survival rates. In this study, we sought to improve on current devices used for hemorrhage control by combining the large volume-filling capabilities and rapid clotting of shape memory polymer (SMP) foams with the swelling capacity of hydrogels. In addition, a hydrogel composition was selected that readily complexes with elemental iodine to impart bactericidal properties to the device. The focus of this work was to verify that the advantages of each respective material (SMP foam and hydrogel) are retained when combined in a composite device. The iodine-doped hydrogel demonstrated an 80% reduction in bacteria viability when cultured with a high bioburden of Staphylococcus aureus. Hydrogel coating of the SMP foam increased fluid uptake by 19× over the uncoated SMP foam. The composite device retained the shape memory behavior of the foam with more than 15× volume expansion after being submerged in 37°C water for 15 min. Finally, the expansion force of the composite was tested to assess potential tissue damage within the wound during device expansion. Expansion forces did not exceed 0.6N, making tissue damage during device expansion unlikely, even when the expanded device diameter is substantially larger than the target wound site. Overall, the enhanced fluid uptake and bactericidal properties of the shape memory foam composite indicate its strong potential as a hemostatic agent to treat non-compressible wounds. No hemostatic device currently used in civilian and combat trauma situations satisfies all the desired criteria for an optimal hemostatic wound dressing. The research presented here sought to improve on current devices by combining the large volume-filling capabilities and rapid clotting of shape memory polymer (SMP) foams with the swelling

  7. Sacred tulsi (ocimum sanctum L.) in traditional medicine and pharmacology.

    Science.gov (United States)

    Khosla, M K

    1995-07-01

    Scared Tulasi (Ocimum sanctum L.) of family Lamiaceae is a wonder ayurvedic herb which is known for its tremendous medicinal properties both in traditional folklore as well as pharmacological system of medicines. Every part of the plant finds its use in one form or the other. Keeping in view the importance of the plant, an attempt has been made to review the various studies carried out in traditional system of medicine as well as modern pharmacological investigations.

  8. A strategy to enhance the antifouling property of coating for direct immersion solid phase microextraction.

    Science.gov (United States)

    Wu, Mian; Zhang, Haibo; Zeng, Baizhao; Zhao, Faqiong

    2015-03-06

    This paper presents a new approach for improving the antifouling property of solid-phase microextraction (SPME) coating. The SPME fiber was fabricated by electrodeposition of polyaniline (PANI) on stainless steel wire, followed by covering with an external layer of Nafion. The Nafion layer was able to block the interfering components in the matrix while the fiber was used for the direct extraction of several parabens. At the same time, the selectivity and stability of the SPME fiber was also improved. The adsorption coefficient and saturation-adsorption amount were determined, which showed that the extraction capability of the resulting fiber was similar to that of the original PANI fiber toward parabens. In addition, the fiber exhibited enhanced robustness in direct contact with complex matrix such as orange juice. After it was used for 110-150 adsorption-desorption cycles, its extraction efficiency decreased by 14-16% compared with the maximum measured value. This was a dramatic improvement when compared with the PANI fiber. Hence, the fiber was suitable for direct immersion SPME. Copyright © 2015 Elsevier B.V. All rights reserved.

  9. NiO@ZnO heterostructured nanotubes: coelectrospinning fabrication, characterization, and highly enhanced gas sensing properties.

    Science.gov (United States)

    Xu, Lin; Zheng, Ruifang; Liu, Shuhai; Song, Jian; Chen, Jiansheng; Dong, Biao; Song, Hongwei

    2012-07-16

    Novel NiO@ZnO heterostructured nanotubes (NTs) were fabricated by the coelectrospinning method, consisting of external hexagonal ZnO shell and internal cubic NiO NTs. They are carefully investigated by scanning electron microscopy, transmission electron microscopy, scanning transmission electron microscopy, energy-dispersive X-ray spectroscopy mapping, X-ray diffraction, and X-ray photoelectron spectroscopy techniques. A reasonable formation mechanism of the hierarchical NiO@ZnO NTs is proposed, which is discussed from the view of degradation temperature of different polymers and the amount of inorganic salts. They were then explored for fabrication of H(2)S gas sensors. The gas sensing test reveals that compared with the pure ZnO, NiO, and the ZnO-NiO mixed gas sensors, hierarchical gas sensor exhibits highly improved sensing performances to dilute hydrogen sulfide (H(2)S) gas. The response of the optimum NiO@ZnO NTs sensor to 50 ppm H(2)S increases as high as 2.7-23.7 times compared to the other sensors, whereas the response and recovery times also become shorter considerably. These enhanced gas sensing properties are closely related to the change of nanostructure and activity of ZnO and NiO nanocrystals as well as combination of homo- and heterointerfaces in the optimum gas sensor, which are confirmed by a series of well-designed experiments.

  10. Aqueous Phase Synthesis and Enhanced Field Emission Properties of ZnO-Sulfide Heterojunction Nanowires

    Science.gov (United States)

    Wang, Guojing; Li, Zhengcao; Li, Mingyang; Chen, Chienhua; Lv, Shasha; Liao, Jiecui

    2016-01-01

    ZnO-CdS, ZnO-ZnS, and ZnO-Ag2S core-shell heterojunction structures were fabricated using low-temperature, facile and simple aqueous solution approaches. The polycrystalline sulfide shells effectively enhance the field emission (FE) properties of ZnO nanowires arrays (NWAs). This results from the formation of the staggered gap heterointerface (ZnO-sulfide) which could lead to an energy well at the interfaces. Hence, electrons can be collected when an electric field is applied. It is observed that ZnO-ZnS NWAs have the lowest turn-on field (3.0 Vμm−1), compared with ZnO-CdS NWAs (6.3 Vμm−1) and ZnO-Ag2S NWAs (5.0 Vμm−1). This may be associated with the pyramid-like ZnS shell which increases the number of emission nanotips. Moreover, the Fowler-Nordheim (F-N) plot displays a nonlinear relationship in the low and high electric field regions caused by the double well potential effect of the heterojunction structures. PMID:27387653

  11. OPTIMIZATION OF PROCESS PARAMETERS FOR ENHANCED MECHANICAL PROPERTIES OF POLYPROPYLENE TERNARY NANOCOMPOSITES

    Directory of Open Access Journals (Sweden)

    Oladipupo Olaosebikan Ogunleye

    2015-02-01

    Full Text Available Preparation of Polypropylene ternary nanocomposites (PPTN was accomplished by blending multiwall carbon nanotube (MWCNT in polypropylene/clay binary system using a melt intercalation method. The effects of MWCNT loadings (A, melting temperature (B and mixing speed (C were investigated and optimized using central composite design. The analysis of the fitted cubic model clearly indicated that A and B were the main factors influencing the tensile properties at a fixed value of C. However, the analysis of variance showed that the interactions between the process parameters, such as; AB, AC, AB2, A2B and ABC, were highly significant on both tensile strength and Young’s modulus enhancement, while no interaction is significant in all models considered for elongation. The established optimal conditions gave 0.17%, 165 °C, and 120 rpm for A, B and C, respectively. These conditions yielded a percentage increase of 57 and 63% for tensile strength and Young’s modulus respectively compared to the virgin Polypropylene used.

  12. Preparation and Properties of Polymer/Vermiculite Hybrid Superabsorbent Reinforced by Fiber for Enhanced Oil Recovery

    Directory of Open Access Journals (Sweden)

    Fayang Jin

    2014-01-01

    Full Text Available A series of polymer/clay hybrid superabsorbent composites (SACFs comprising acrylamide, acrylic acid, sodium 2-acrylamido-tetradecyl sulfonate, fiber, and vermiculite by in situ intercalation and exfoliated method was successfully synthesized. The structure of SACFs was characterized by IR, SXRD, and SEM measurements. Much notable absorbency for SACF-2 was observed compared to that for SACF-1 in the absence of hydrophobic group in the high cationic solution due to the alkyl carbon chain and sulfonic acid group of hydrophobic moistures protecting the cations from attacking the carboxylate groups. What is more, high temperature fiber which acts as bridge connection for the polymeric network structure enhanced both toughness and strength for SACF-4 in the harsh conditions. At the total dissolved substance of 212000 mg/L for Tarim Basin injected water and the temperature of 120°C, desired absorbency as well as water retaining property for SACF-4 was observed during the long period of thermal ageing. Core flooding experiments demonstrated that SACFs could migrate as amoeba in the porous medium and accumulated in the narrow channel to adjust injection profile, promoting the subsequent water diverting into the unswept zones. Finally, characteristic parameters for SACFs calculated from flooding experiment further confirmed these polymer/clay hybrid composites reinforced by fiber would have robust application in the mature oilfield for profile control.

  13. Sustainable and smart keratin hydrogel with pH-sensitive swelling and enhanced mechanical properties.

    Science.gov (United States)

    Peralta Ramos, María Luz; González, Joaquín Antonio; Fabian, Lucas; Pérez, Claudio Javier; Villanueva, María Emilia; Copello, Guillermo Javier

    2017-09-01

    Protein based hydrogels are a very interesting type of biomaterials with many probed strengths related to their source and chemical structure. Biocompatibility and biodegradability are accompanied by affordability when it comes to low cost sources. The main keratin source is agroindustrial waste, such as feathers, horns, hooves, hair and wool. Thus, the main cost of keratin hydrogels derives from their processing. Here is presented a new strategy for the obtaining of a keratin hydrogel with enhanced mechanical properties using low cost reagents. This keratin hydrogel is stiff enough to allow handling without special cares and also presenting a reversible pH-responsive behavior. The minimum swelling is observed at low pH due to a collapsed and disordered protein network with water tightly adsorbed to the hydrophilic sites. The swelling rises significantly above pH6 and the maximum swelling appears above pH8 where an expanded network allows water to enter to the pores. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Enhanced microwave absorption properties of graphite nanoflakes by coating hexagonal boron nitride nanocrystals

    KAUST Repository

    Zhong, Bo

    2017-05-31

    We report herein the synthesis of a novel hexagonal boron nitride nanocrystal/graphite nanoflake (h-BNNC/GNF) composite through a wet-chemistry coating of graphite nanoflakes and subsequent in-situ thermal treatment process. The characterization results of X-ray diffraction, scanning electron microscope, transmission electron microscope, energy dispersive X-ray spectrum, and X-ray photoelectron spectroscopy demonstrate that h-BNNCs with diameter of tens of nanometers are highly crystallized and anchored on the surfaces of graphite nanoflakes without obvious aggregation. The minimum reflection loss (RL) value of the h-BNNC/GNF based absorbers could reach −32.38dB (>99.99% attenuation) with the absorber thickness of 2.0mm. This result is superior to the other graphite based and some dielectric loss microwave absorption materials recently reported. Moreover, the frequency range where the RL is less than −10dB is 3.49-17.28GHz with the corresponding thickness of 5.0 to 1.5mm. This reveals a better electromagnetic microwave absorption performance of h-BNNC/GNFs from the X-band to the Ku-band. The remarkable enhancement of the electromagnetic microwave absorption properties of h-BNNC/GNFs can be assigned to the increase of multiple scattering, interface polarization as well as the improvement of the electromagnetic impedance matching of graphite nanoflakes after being coated with h-BNNCs.

  15. Synthesis of hybrid paper sheets with enhanced air barrier and antimicrobial properties for food packaging.

    Science.gov (United States)

    El-Samahy, Magda A; Mohamed, Salah A A; Abdel Rehim, Mona H; Mohram, Maysa E

    2017-07-15

    Paper sheets made from bagasse pulp have been modified using nanocellulose (NC) obtained from the same raw material. Modification of paper sheets have been carried out either through loading of paper with different concentrations of NC and antibacterial agent, Chitosan (Ch) during making sheets, or by surface coating of the paper. Crystals of NC extracted using concentrated sulfuric acid from bagasse pulp were found to have crystallinity index (CrI) 90%. Morphology of obtained NC has been confirmed by TEM and images revealed formation of NC crystals with large size distribution ranges from 4 to 60nm. Mechanical properties and air permeability of paper sheets loaded with different ratios of NC and Ch have been investigated. The results showed that presence of NC did not negatively affect the obtained modified paper sheets, while air permeability decreased with adding 8% NC to paper matrix. On the other hand, surface coverage of paper sheets with NC greatly reduced air permeability. Antimicrobial investigations carried out by optical density method indicated that presence of Ch in the paper sheets as an additive or in a coating formulation enhanced paper resistance to different microorganisms especially those causing food poisoning. The current study confirms that the modified paper can have potential application in food packaging. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Diatom frustules decorated with zinc oxide nanoparticles for enhanced optical properties

    Science.gov (United States)

    Lamastra, F. R.; Grilli, M. L.; Leahu, G.; Belardini, A.; Li Voti, R.; Sibilia, C.; Salvatori, D.; Cacciotti, I.; Nanni, F.

    2017-09-01

    Zinc oxide (ZnO) nanoparticles were synthesized on diatomite (DE) surface by a low temperature sol gel technique, starting from zinc acetate dihydrate (Zn(CH3COO)2 · 2H2O) solution in water/ethyl alcohol, in presence of triethanolamine (TEA) with functions of Zn2+ chelating agent, catalyst and mediator of nanoparticle growth on DE surface. Microstructural features were investigated by field emission scanning electron microscopy and x-ray diffraction. ZnO crystalline nanoparticles, well distributed both on the surface and into the porous architecture of diatomite, were obtained just after the synthesis carried out at 80 °C without the need of calcination treatments. The optical properties of ZnO/DE hybrid powders were measured for the first time by means of photoacoustic spectroscopy (PAS). A new method to retrieve both the optical absorption and scattering coefficients from PAS is here discussed for powder aggregates. The fingerprint of the zinc oxide nanoparticles has been highlighted in the Mie scattering resonance in the UV-Vis range, and in the enhancement of the optical absorption with respect to diatomite.

  17. Isocyanate toughening of pCBT/organoclay nanocomposites with exfoliated structure and enhanced mechanical properties

    Directory of Open Access Journals (Sweden)

    T. Abt

    2014-12-01

    Full Text Available Cyclic butylene terephthalate (CBT® is an interesting matrix material for the preparation of nanocomposites due to its very low, water-like melt viscosity which favours clay exfoliation. Nevertheless, polymerized CBT (pCBT is inherently brittle. This paper reports the preparation of isocyanate-toughened nanocomposites made from CBT and organo-modified montmorillonite. The role of the organoclay as reinforcement and the polymeric isocyanate (PMDI as toughening agent on the properties of pCBT was studied. The organoclay increased the stiffness and strength by up to 20% whereas the PMDI improved the deformation behaviour. However, the PMDI did not affect the degree of clay dispersion or exfoliation and flocculated-intercalated structures were observed. The compatibility between the pCBT matrix and clay was further increased by preparing PMDI-tethered intercalated organoclay. The modified organoclay then exfoliated during ring-opening polymerization and yielded true pCBT/clay nanocomposites. This work demonstrates that reactive chain extension of CBT with a polyfunctional isocyanate is an effective method to obtain toughened pCBT nanocomposites. Moreover, isocyanates can enhance the compatibility between pCBT and nanofiller as well as the degree of exfoliation.

  18. Environmental Synthesis of Few Layers Graphene Sheets Using Ultrasonic Exfoliation with Enhanced Electrical and Thermal Properties.

    Science.gov (United States)

    Noroozi, Monir; Zakaria, Azmi; Radiman, Shahidan; Abdul Wahab, Zaidan

    2016-01-01

    In this paper, we report how few layers graphene that can be produced in large quantity with low defect ratio from exfoliation of graphite by using a high intensity probe sonication in water containing liquid hand soap and PVP. It was founded that the graphene powder obtained by this simple exfoliation method after the heat treatment had an excellent exfoliation into a single or layered graphene sheets. The UV-visible spectroscopy, FESEM, TEM, X-ray powder diffraction and Raman spectroscopy was used to analyse the graphene product. The thermal diffusivity of the samples was analysed using a highly accurate thermal-wave cavity photothermal technique. The data obtained showed excellent enhancement in the thermal diffusivity of the graphene dispersion. This well-dispersed graphene was then used to fabricate an electrically conductive polymer-graphene film composite. The results demonstrated that this low cost and environmental friendly technique allowed to the production of high quality layered graphene sheets, improved the thermal and electrical properties. This may find use in the wide range of applications based on graphene.

  19. Environmental Synthesis of Few Layers Graphene Sheets Using Ultrasonic Exfoliation with Enhanced Electrical and Thermal Properties.

    Directory of Open Access Journals (Sweden)

    Monir Noroozi

    Full Text Available In this paper, we report how few layers graphene that can be produced in large quantity with low defect ratio from exfoliation of graphite by using a high intensity probe sonication in water containing liquid hand soap and PVP. It was founded that the graphene powder obtained by this simple exfoliation method after the heat treatment had an excellent exfoliation into a single or layered graphene sheets. The UV-visible spectroscopy, FESEM, TEM, X-ray powder diffraction and Raman spectroscopy was used to analyse the graphene product. The thermal diffusivity of the samples was analysed using a highly accurate thermal-wave cavity photothermal technique. The data obtained showed excellent enhancement in the thermal diffusivity of the graphene dispersion. This well-dispersed graphene was then used to fabricate an electrically conductive polymer-graphene film composite. The results demonstrated that this low cost and environmental friendly technique allowed to the production of high quality layered graphene sheets, improved the thermal and electrical properties. This may find use in the wide range of applications based on graphene.

  20. MEMS-based Ni-B probe with enhanced mechanical properties for fine pitch testing

    Science.gov (United States)

    Kim, Kyongtae; Kwon, Hong-Beom; Ahn, Hye-Rin; Kim, Yong-Jun

    2017-12-01

    We fabricated and characterized microelectromechanical systems (MEMS)-based Ni-B probes with enhanced mechanical properties for fine pitch testing. The Ni-B micro-probes were compared with conventional Ni-Co micro-probes in terms of the mechanical performance and thermal effect. The elastic modulus and hardness of Ni-B were found to be 240.4 and 10.9 GPa, respectively, which surpass those of Ni-Co. The Ni-B micro-probes had a higher contact force than the Ni-Co micro-probes by an average of 41.38% owing to the higher elastic modulus. The Ni-B micro-probes had a lower average permanent deformation than the Ni-Co micro-probes after the same overdrive was applied for 1 h by 56.58 µm. The temperature was found to have a negligible effect on the Ni-B micro-probes. These results show that Ni-B micro-probes are useful for fine pitch testing and a potential candidate for replacing conventional Ni-Co micro-probes owing to their advanced mechanical and thermal characteristics.

  1. Enhancing the mechanical properties of electrospun polyester mats by heat treatment

    Directory of Open Access Journals (Sweden)

    M. Kancheva

    2015-01-01

    Full Text Available Microfibrous materials with a targeted design based on poly(L-lactic acid (PLA and poly(ε-caprolactone (PCL were prepared by electrospinning and by combining electrospinning and electrospraying. Several approaches were used: (i electrospinning of a common solution of the two polymers, (ii simultaneous electrospinning of two separate solutions of PLA and PCL, (iii electrospinning of PLA solution in conjunction with electrospraying of PCL solution, and (iv alternating layer-by-layer deposition by electrospinning of separate PLA and PCL solutions. The mats were heated at the melting temperature of PCL (60°", thus achieving melting of PCL fibers/particles and thermal sealing of the fibers. The mats subjected to thermal treatment were characterized by greater mean fiber diameters and reduced values of the water contact angle compared to the pristine mats. Heat treatment of the mats affected their thermal stability and led to an increase in the crystallinity degree of PLA incorporated in the mats, whereas that of PCL was reduced. All mats were characterized by enhanced mechanical properties after thermal treatment as compared to the non-treated fibrous materials.

  2. Enhanced mechanical properties of thermosensitive chitosan hydrogel by silk fibers for cartilage tissue engineering.

    Science.gov (United States)

    Mirahmadi, Fereshteh; Tafazzoli-Shadpour, Mohammad; Shokrgozar, Mohammad Ali; Bonakdar, Shahin

    2013-12-01

    Articular cartilage has limited repair capability following traumatic injuries and current methods of treatment remain inefficient. Reconstructing cartilage provides a new way for cartilage repair and natural polymers are often used as scaffold because of their biocompatibility and biofunctionality. In this study, we added degummed chopped silk fibers and electrospun silk fibers to the thermosensitive chitosan/glycerophosphate hydrogels to reinforce two hydrogel constructs which were used as scaffold for hyaline cartilage regeneration. The gelation temperature and gelation time of hydrogel were analyzed by the rheometer and vial tilting method. Mechanical characterization was measured by uniaxial compression, indentation and dynamic mechanical analysis assay. Chondrocytes were then harvested from the knee joint of the New Zealand white rabbits and cultured in constructs. The cell proliferation, viability, production of glycosaminoglycans and collagen type II were assessed. The results showed that mechanical properties of the hydrogel were significantly enhanced when a hybrid with two layers of electrospun silk fibers was made. The results of GAG and collagen type II in cell-seeded scaffolds indicate support of the chondrogenic phenotype for chondrocytes with a significant increase in degummed silk fiber-hydrogel composite for GAG content and in two-layer electrospun fiber-hydrogel composite for Col II. It was concluded that these two modified scaffolds could be employed for cartilage tissue engineering. © 2013.

  3. Enhanced piezoelectric properties of vertically aligned single-crystalline NKN nano-rod arrays.

    Science.gov (United States)

    Kang, Min-Gyu; Oh, Seung-Min; Jung, Woo-Suk; Moon, Hi Gyu; Baek, Seung-Hyub; Nahm, Sahn; Yoon, Seok-Jin; Kang, Chong-Yun

    2015-05-08

    Piezoelectric materials capable of converting between mechanical and electrical energy have a great range of potential applications in micro- and nano-scale smart devices; however, their performance tends to be greatly degraded when reduced to a thin film due to the large clamping force by the substrate and surrounding materials. Herein, we report an effective method for synthesizing isolated piezoelectric nano-materials as means to relax the clamping force and recover original piezoelectric properties of the materials. Using this, environmentally friendly single-crystalline NaxK1-xNbO3 (NKN) piezoelectric nano-rod arrays were successfully synthesized by conventional pulsed-laser deposition and demonstrated to have a remarkably enhanced piezoelectric performance. The shape of the nano-structure was also found to be easily manipulated by varying the energy conditions of the physical vapor. We anticipate that this work will provide a way to produce piezoelectric micro- and nano-devices suitable for practical application, and in doing so, open a new path for the development of complex metal-oxide nano-structures.

  4. Enhanced microwave absorption properties of graphite nanoflakes by coating hexagonal boron nitride nanocrystals

    Science.gov (United States)

    Zhong, Bo; Liu, Wei; Yu, Yuanlie; Xia, Long; Zhang, Jiulin; Chai, Zhenfei; Wen, Guangwu

    2017-10-01

    We report herein the synthesis of a novel hexagonal boron nitride nanocrystal/graphite nanoflake (h-BNNC/GNF) composite through a wet-chemistry coating of graphite nanoflakes and subsequent in-situ thermal treatment process. The characterization results of X-ray diffraction, scanning electron microscope, transmission electron microscope, energy dispersive X-ray spectrum, and X-ray photoelectron spectroscopy demonstrate that h-BNNCs with diameter of tens of nanometers are highly crystallized and anchored on the surfaces of graphite nanoflakes without obvious aggregation. The minimum reflection loss (RL) value of the h-BNNC/GNF based absorbers could reach -32.38 dB (>99.99% attenuation) with the absorber thickness of 2.0 mm. This result is superior to the other graphite based and some dielectric loss microwave absorption materials recently reported. Moreover, the frequency range where the RL is less than -10 dB is 3.49-17.28 GHz with the corresponding thickness of 5.0-1.5 mm. This reveals a better electromagnetic microwave absorption performance of h-BNNC/GNFs from the X-band to the Ku-band. The remarkable enhancement of the electromagnetic microwave absorption properties of h-BNNC/GNFs can be assigned to the increase of multiple scattering, interface polarization as well as the improvement of the electromagnetic impedance matching of graphite nanoflakes after being coated with h-BNNCs.

  5. Thymol nanoemulsified by whey protein-maltodextrin conjugates: the enhanced emulsifying capacity and antilisterial properties in milk by propylene glycol.

    Science.gov (United States)

    Xue, Jia; Davidson, P Michael; Zhong, Qixin

    2013-12-26

    The objective of this research was to enhance the capability of whey protein isolate-maltodextrin conjugates in nanoemulsifying thymol using propylene glycol to improve antilisterial properties in milk. Thymol was predissolved in PG and emulsified in 7% conjugate solution. Transparent dispersions with mean diameters of propylene glycol.

  6. Enhancement of nonlinear optical properties of BaTiO3 nanoparticles by the addition of silver seeds: comment.

    Science.gov (United States)

    George, Nibu A

    2017-07-24

    This is a comment on the previously published paper "Enhancement of nonlinear optical properties of BaTiO3 nanoparticles by the addition of silver seeds," [Opt. Express20, 26511 (2012)10.1364/OE.20.026511]. An erroneous equation given in the manuscript is corrected with a more accurate equation in this comment.

  7. Method of producing an item with enhanced wetting properties by fast replication and replication tool used in the method

    DEFF Research Database (Denmark)

    2016-01-01

    an item with enhanced wetting properties uses the replication tool (1) to form an item (4) with a general shape as defined by the tool surface. The formed item (4) comprises a microscale textured replica surface (5a, 5b, 5c) with a lateral arrangement of polydisperse microscale protrusions....

  8. Emergent Low-Symmetry Phases and Large Property Enhancements in Ferroelectric KNbO 3 Bulk Crystals

    Energy Technology Data Exchange (ETDEWEB)

    Lummen, Tom T. A. [Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA 16802 USA; Leung, J. [Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA 16802 USA; Kumar, Amit [School of Mathematics and Physics, Queen' s University Belfast, University Road, Belfast BT71NN Northern Ireland UK; Wu, X. [Department of Physics, University of Texas at Austin, Austin TX 78712 USA; Ren, Y. [Department of Physics, University of Texas at Austin, Austin TX 78712 USA; VanLeeuwen, Brian K. [Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA 16802 USA; Haislmaier, Ryan C. [Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA 16802 USA; Holt, Martin [Center for Nanoscale Materials, Argonne National Laboratory, Argonne IL 60439 USA; Lai, Keji [Department of Physics, University of Texas at Austin, Austin TX 78712 USA; Kalinin, Sergei V. [Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge TN 37831 USA; Gopalan, Venkatraman [Department of Materials Science and Engineering, Pennsylvania State University, University Park, PA 16802 USA

    2017-06-19

    The design of new or enhanced functionality in materials is traditionally viewed as requiring the discovery of new chemical compositions through synthesis. Large property enhancements may however also be hidden within already well-known materials, when their structural symmetry is deviated from equilibrium through a small local strain or field. Here, the discovery of enhanced material properties associated with a new metastable phase of monoclinic symmetry within bulk KNbO3 is reported. This phase is found to coexist with the nominal orthorhombic phase at room temperature, and is both induced by and stabilized with local strains generated by a network of ferroelectric domain walls. While the local microstructural shear strain involved is only approximate to 0.017%, the concurrent symmetry reduction results in an optical second harmonic generation response that is over 550% higher at room temperature. Moreover, the meandering walls of the low-symmetry domains also exhibit enhanced electrical conductivity on the order of 1 S m(-1). This discovery reveals a potential new route to local engineering of significant property enhancements and conductivity through symmetry lowering in ferroelectric crystals.

  9. Harnessing microbial subsurface metal reduction activities to synthesise nanoscale cobalt ferrite with enhanced magnetic properties

    Energy Technology Data Exchange (ETDEWEB)

    Coker, Victoria S.; Telling, Neil D.; van der Laan, Gerrit; Pattrick, Richard A.D.; Pearce, Carolyn I.; Arenholz, Elke; Tuna, Floriana; Winpenny, Richard E.P.; Lloyd, Jonathan R.

    2009-03-24

    Nanoscale ferrimagnetic particles have a diverse range of uses from directed cancer therapy and drug delivery systems to magnetic recording media and transducers. Such applications require the production of monodisperse nanoparticles with well-controlled size, composition, and magnetic properties. To fabricate these materials purely using synthetic methods is costly in both environmental and economical terms. However, metal-reducing microorganisms offer an untapped resource to produce these materials. Here, the Fe(III)-reducing bacterium Geobacter sulfurreducens is used to synthesize magnetic iron oxide nanoparticles. A combination of electron microscopy, soft X-ray spectroscopy, and magnetometry techniques was employed to show that this method of biosynthesis results in high yields of crystalline nanoparticles with a narrow size distribution and magnetic properties equal to the best chemically synthesized materials. In particular, it is demonstrated here that cobalt ferrite (CoFe{sub 2}O{sub 4}) nanoparticles with low temperature coercivity approaching 8 kOe and an effective anisotropy constant of {approx} 10{sup 6} erg cm{sup -3} can be manufactured through this biotechnological route. The dramatic enhancement in the magnetic properties of the nanoparticles by the introduction of high quantities of Co into the spinel structure represents a significant advance over previous biomineralization studies in this area using magnetotactic bacteria. The successful production of nanoparticulate ferrites achieved in this study at high yields could open up the way for the scaled-up industrial manufacture of nanoparticles using environmentally benign methodologies. Production of ferromagnetic nanoparticles for pioneering cancer therapy, drug delivery, chemical sensors, catalytic activity, photoconductive materials, as well as more traditional uses in data storage embodies a large area of inorganic synthesis research. In particular, the addition of transition metals other than

  10. Common mullein, pharmacological and chemical aspects

    Directory of Open Access Journals (Sweden)

    Muhammad Riaz

    Full Text Available Verbascum thapsus L. [Khardhag or Common mullein], a member of the family Scrophulariaceae, is a famous herb that is found all over Europe, in temperate Asia, in North America and is well-reputed due to its medicinal properties. This medicinal herb contains various chemical constituents like saponins, iridoid and phenylethanoid glycosides, flavonoids, vitamin C and minerals. It is famous in various communities worldwide for the treatment of various disorders of both humans and animals aliments. A number of pharmacological activities such as anti-inflammatory, antioxidant, anticancer, antimicrobial, antiviral, antihepatotoxic and anti-hyperlipidemic activity have been ascribed to this plant. The plant is used to treat tuberculosis also, earache and bronchitis. In the present paper botanical and ethnomedicinal description, pharmacological profile and phytochemistry of this herb is being discussed.

  11. 14-Day thawed plasma retains clot enhancing properties and inhibits tPA-induced fibrinolysis.

    Science.gov (United States)

    Huebner, Benjamin R; Moore, Ernest E; Moore, Hunter B; Shepherd-Singh, Raymond; Sauaia, Angela; Stettler, Gregory R; Nunns, Geoffrey R; Silliman, Christopher C

    2017-11-01

    Plasma-first resuscitation attenuates trauma-induced coagulopathy (TIC); however, the logistics of plasma-first resuscitation require thawed plasma (TP) be readily available due to the obligatory thawing time of fresh frozen plasma (FFP). The current standard is storage of TP for up to 5 days at 4°C, based on factor levels at outdate, for use in patients at risk for TIC, but there remains a 2.2% outdated wastage rate. However, the multitude of plasma proteins in attenuating TIC remains unknown. We hypothesize that TP retains the ability to enhance clotting and reduce tPA-induced fibrinolysis at 14-day storage. FFP was thawed and stored at 4°C at the following intervals: 14, 10, 7, 5, 3, and 1-day prior to the experiment. Healthy volunteers underwent blood draws followed by 50% dilution with TP stored at previously mentioned intervals as well as FFP, normal saline (NS), albumin, and whole blood (WB) control. Samples underwent tPA-modified (75 ng/mL) thrombelastography (TEG) with analysis of R-time, angle, maximum amplitude (MA), and LY30. TEG properties did not change significantly over the thawed storage. 14-day TP retained the ability to inhibit tPA-induced hyperfibrinolysis (median LY30% 9.6%) similar to FFP (5.6%), WB (14.6%), and superior to albumin (59.3%) and NS (58.1%). 14-day TP also retained faster clot formation (median angle, 66.2°) and superior clot strength (MA, 61.5 mm) to albumin (34.8°, 21.6 mm) and NS (41.6°, 32.2 mm). TP plasma stored for 14 days retains clot-enhancing ability and resistance to clot degradation similar to FFP. A clinical trial is needed to validate these in vitro results. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Characterization of Metabolic, Diffusion, and Perfusion Properties in GBM: Contrast-Enhancing versus Non-Enhancing Tumor

    Directory of Open Access Journals (Sweden)

    Adam Autry

    2017-12-01

    Full Text Available BACKGROUND: Although the contrast-enhancing (CE lesion on T1-weighted MR images is widely used as a surrogate for glioblastoma (GBM, there are also non-enhancing regions of infiltrative tumor within the T2-weighted lesion, which elude radiologic detection. Because non-enhancing GBM (Enh− challenges clinical patient management as latent disease, this study sought to characterize ex vivo metabolic profiles from Enh− and CE GBM (Enh+ samples, alongside histological and in vivo MR parameters, to assist in defining criteria for estimating total tumor burden. Methods: Fifty-six patients with newly diagnosed GBM received a multi-parametric pre-surgical MR examination. Targets for obtaining image-guided tissue samples were defined based on in vivo parameters that were suspicious for tumor. The actual location from where tissue samples were obtained was recorded, and half of each sample was analyzed for histopathology while the other half was scanned using HR-MAS spectroscopy. Results: The Enh+ and Enh− tumor samples demonstrated comparable mitotic activity, but also significant heterogeneity in microvascular morphology. Ex vivo spectroscopic parameters indicated similar levels of total choline and N-acetylaspartate between these contrast-based radiographic subtypes of GBM, and characteristic differences in the levels of myo-inositol, creatine/phosphocreatine, and phosphoethanolamine. Analysis of in vivo parameters at the sample locations were consistent with histological and ex vivo metabolic data. CONCLUSIONS: The similarity between ex vivo levels of choline and NAA, and between in vivo levels of choline, NAA and nADC in Enh+ and Enh− tumor, indicate that these parameters can be used in defining non-invasive metrics of total tumor burden for patients with GBM.

  13. Pharmacological inhibition of FTO.

    Directory of Open Access Journals (Sweden)

    Fiona McMurray

    Full Text Available In 2007, a genome wide association study identified a SNP in intron one of the gene encoding human FTO that was associated with increased body mass index. Homozygous risk allele carriers are on average three kg heavier than those homozygous for the protective allele. FTO is a DNA/RNA demethylase, however, how this function affects body weight, if at all, is unknown. Here we aimed to pharmacologically inhibit FTO to examine the effect of its demethylase function in vitro and in vivo as a first step in evaluating the therapeutic potential of FTO. We showed that IOX3, a known inhibitor of the HIF prolyl hydroxylases, decreased protein expression of FTO (in C2C12 cells and reduced maximal respiration rate in vitro. However, FTO protein levels were not significantly altered by treatment of mice with IOX3 at 60 mg/kg every two days. This treatment did not affect body weight, or RER, but did significantly reduce bone mineral density and content and alter adipose tissue distribution. Future compounds designed to selectively inhibit FTO's demethylase activity could be therapeutically useful for the treatment of obesity.

  14. Ion channel pharmacology.

    Science.gov (United States)

    Camerino, Diana Conte; Tricarico, Domenico; Desaphy, Jean-François

    2007-04-01

    Because ion channels are involved in many cellular processes, drugs acting on ion channels have long been used for the treatment of many diseases, especially those affecting electrically excitable tissues. The present review discusses the pharmacology of voltage-gated and neurotransmitter-gated ion channels involved in neurologic diseases, with emphasis on neurologic channelopathies. With the discovery of ion channelopathies, the therapeutic value of many basic drugs targeting ion channels has been confirmed. The understanding of the genotype-phenotype relationship has highlighted possible action mechanisms of other empirically used drugs. Moreover, other ion channels have been pinpointed as potential new drug targets. With regards to therapy of channelopathies, experimental investigations of the intimate drug-channel interactions have demonstrated that channel mutations can either increase or decrease affinity for the drug, modifying its potential therapeutic effect. Together with the discovery of channel gene polymorphisms that may affect drug pharmacodynamics, these findings highlight the need for pharmacogenetic research to allow identification of drugs with more specific effects on channel isoforms or mutants, to increase efficacy and reduce side effects. With a greater understanding of channel genetics, structure, and function, together with the identification of novel primary and secondary channelopathies, the number of ion channel drugs for neurologic channelopathies will increase substantially.

  15. Enhancement in ferroelectric, pyroelectric and photoluminescence properties in dye doped TGS crystals

    Energy Technology Data Exchange (ETDEWEB)

    Sinha, Nidhi [Department of Electronics, SGTB Khalsa College, University of Delhi, Delhi-110007 (India); Goel, Neeti; Singh, B.K.; Gupta, M.K. [Crystal Lab, Department of Physics and Astrophysics, University of Delhi, Delhi-110007 (India); Kumar, Binay, E-mail: bkumar@physics.du.ac.in [Crystal Lab, Department of Physics and Astrophysics, University of Delhi, Delhi-110007 (India)

    2012-06-15

    Pure and dye doped (0.1 and 0.2 mol%) Triglycine Sulfate (TGS) single crystals were grown by slow evaporation technique. A pyramidal coloring pattern, along with XRD and FT-IR studies confirmed the dye doping. Decrease in dielectric constant and increase in Curie temperature (T{sub c}) were observed with increasing doping concentration. Low absorption cut off (231 nm) and high optical transparency (>90%) resulting in large band gap was observed in UV-VIS studies. In addition, strong hyper-luminescent emission bands at 350 and 375 nm were observed in which the relative intensity were found to be reversed as a result of doping. In P-E hysteresis loop studies, a higher curie temperature and an improved and more uniform figure of merit over a large region of the ferroelectric phase were observed. The improved dielectric, optical and ferroelectric/pyroelectric properties make the dye doped TGS crystals better candidate for various opto- and piezo-electronics applications. - Graphical abstract: Dye doping in TGS crystal resulted in hourglass morphology, increased hyper-luminescence intensity, improved T{sub c} and figure of merit. Highlights: Black-Right-Pointing-Pointer Amaranth dye doping in TGS crystals resulted in hourglass morphology. Black-Right-Pointing-Pointer Doping resulted in enhancement of Curie temperature from 49 to 53 Degree-Sign C. Black-Right-Pointing-Pointer Low cut off (230 nm) and wider transmittance window observed. Black-Right-Pointing-Pointer Strong hyper-luminescent emission bands at 350 and 375 nm were observed. Black-Right-Pointing-Pointer High and uniform figure of merit in ferroelectric phase was obtained.

  16. Enhanced Ethanol Gas Sensing Properties of SnO2-Core/ZnO-Shell Nanostructures

    Directory of Open Access Journals (Sweden)

    T. Tharsika

    2014-08-01

    Full Text Available An inexpensive single-step carbon-assisted thermal evaporation method for the growth of SnO2-core/ZnO-shell nanostructures is described, and the ethanol sensing properties are presented. The structure and phases of the grown nanostructures are investigated by field-emission scanning electron microscopy (FESEM, transmission electron microscopy (TEM and X-ray diffraction (XRD techniques. XRD analysis indicates that the core-shell nanostructures have good crystallinity. At a lower growth duration of 15 min, only SnO2 nanowires with a rectangular cross-section are observed, while the ZnO shell is observed when the growth time is increased to 30 min. Core-shell hierarchical nanostructures are present for a growth time exceeding 60 min. The growth mechanism for SnO2-core/ZnO-shell nanowires and hierarchical nanostructures are also discussed. The sensitivity of the synthesized SnO2-core/ZnO-shell nanostructures towards ethanol sensing is investigated. Results show that the SnO2-core/ZnO-shell nanostructures deposited at 90 min exhibit enhanced sensitivity to ethanol. The sensitivity of SnO2-core/ZnO-shell nanostructures towards 20 ppm ethanol gas at 400 °C is about ~5-times that of SnO2 nanowires. This improvement in ethanol gas response is attributed to high active sensing sites and the synergistic effect of the encapsulation of SnO2 by ZnO nanostructures.

  17. Enhanced Ethanol Gas Sensing Properties of SnO2-Core/ZnO-Shell Nanostructures

    Science.gov (United States)

    Tharsika, T.; Haseeb, A. S. M. A.; Akbar, Sheikh A.; Sabri, Mohd Faizul Mohd; Hoong, Wong Yew

    2014-01-01

    An inexpensive single-step carbon-assisted thermal evaporation method for the growth of SnO2-core/ZnO-shell nanostructures is described, and the ethanol sensing properties are presented. The structure and phases of the grown nanostructures are investigated by field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and X-ray diffraction (XRD) techniques. XRD analysis indicates that the core-shell nanostructures have good crystallinity. At a lower growth duration of 15 min, only SnO2 nanowires with a rectangular cross-section are observed, while the ZnO shell is observed when the growth time is increased to 30 min. Core-shell hierarchical nanostructures are present for a growth time exceeding 60 min. The growth mechanism for SnO2-core/ZnO-shell nanowires and hierarchical nanostructures are also discussed. The sensitivity of the synthesized SnO2-core/ZnO-shell nanostructures towards ethanol sensing is investigated. Results show that the SnO2-core/ZnO-shell nanostructures deposited at 90 min exhibit enhanced sensitivity to ethanol. The sensitivity of SnO2-core/ZnO-shell nanostructures towards 20 ppm ethanol gas at 400 °C is about ∼5-times that of SnO2 nanowires. This improvement in ethanol gas response is attributed to high active sensing sites and the synergistic effect of the encapsulation of SnO2 by ZnO nanostructures. PMID:25116903

  18. Heat and Radiofrequency Plasma Glow Discharge Pretreatment of a Titanium Alloy: Eveidence for Enhanced Osteoinductive Properties

    Science.gov (United States)

    Rapuano, Bruce E.; Singh, Herman; Boskey, Adele L.; Doty, Stephen B.; MacDonald, Daniel E.

    2013-01-01

    It is believed that orthopedic and implant longevity can be improved by optimizing fixation, or direct bone-implant contact, through the stimulation of new bone formation around the implant. The purpose of this study was to determine whether heat (600°C) or radiofrequency plasma glow discharge (RFGD) pretreatment of Ti6Al4V stimulated calcium-phosphate mineral formation in cultures of attached MC3T3 osteoprogenitor cells with or without a fibronectin coating. Calcium-phosphate mineral was analyzed by flame atomic absorption spectrophotometry, scanning electron microscopy (SEM)/electron dispersive X-ray microanalysis (EDAX) and Fourier transformed infrared spectroscopy (FTIR). RFGD and heat pretreatments produced a general pattern of increased total soluble calcium levels, although the effect of heat pretreatment was greater than that of RFGD. SEM/EDAX showed the presence of calcium-and phosphorus-containing particles on untreated and treated disks that were more numerous on fibronectin-coated disks. These particles were observed earliest (1 week) on RFGD-pretreated surfaces. FTIR analyses showed that the heat pretreatment produced a general pattern of increased levels of apatite mineral at 2–4 weeks; a greater effect was observed for fibronectin-coated disks compared to uncoated disks. The observed findings suggest that heat pretreatment of Ti6Al4V increased the total mass of the mineral formed in MC3T3 osteoprogenitor cell cultures more than RFGD while the latter pretreatment hastened the early deposition of mineral. These findings help to support the hypothesis that the pretreatments enhance the osteoinductive properties of the alloy. PMID:23494951

  19. Enhanced pyroelectric and piezoelectric properties of PZT with aligned porosity for energy harvesting applications.

    Science.gov (United States)

    Zhang, Yan; Xie, Mengying; Roscow, James; Bao, Yinxiang; Zhou, Kechao; Zhang, Dou; Bowen, Chris R

    2017-04-14

    This paper demonstrates the significant benefits of exploiting highly aligned porosity in piezoelectric and pyroelectric materials for improved energy harvesting performance. Porous lead zirconate (PZT) ceramics with aligned pore channels and varying fractions of porosity were manufactured in a water-based suspension using freeze-casting. The aligned porous PZT ceramics were characterized in detail for both piezoelectric and pyroelectric properties and their energy harvesting performance figures of merit were assessed parallel and perpendicular to the freezing direction. As a result of the introduction of porosity into the ceramic microstructure, high piezoelectric and pyroelectric harvesting figures of merits were achieved for porous freeze-cast PZT compared to dense PZT due to the reduced permittivity and volume specific heat capacity. Experimental results were compared to parallel and series analytical models with good agreement and the PZT with porosity aligned parallel to the freezing direction exhibited the highest piezoelectric and pyroelectric harvesting response; this was a result of the enhanced interconnectivity of the ferroelectric material along the poling direction and reduced fraction of unpoled material that leads to a higher polarization. A complete thermal energy harvesting system, composed of a parallel-aligned PZT harvester element and an AC/DC converter, was successfully demonstrated by charging a storage capacitor. The maximum energy density generated by the 60 vol% porous parallel-connected PZT when subjected to thermal oscillations was 1653 μJ cm(-3), which was 374% higher than that of the dense PZT with an energy density of 446 μJ cm(-3). The results are beneficial for the design and manufacture of high performance porous pyroelectric and piezoelectric materials in devices for energy harvesting and sensor applications.

  20. Enhanced fluorescent properties of an OmpT site deleted mutant of Green Fluorescent Protein

    Directory of Open Access Journals (Sweden)

    Kumar Avijeet

    2010-04-01

    Full Text Available Abstract Background The green fluorescent protein has revolutionized many areas of cell biology and biotechnology since it is widely used in determining gene expression and for localization of protein expression. Expression of recombinant GFP in E. coli K12 host from pBAD24M-GFP construct upon arabinose induction was significantly lower than that seen in E. coli B cells with higher expression at 30°C as compared to 37°C in E. coli K12 hosts. Since OmpT levels are higher at 37°C than at 30°C, it prompted us to modify the OmpT proteolytic sites of GFP and examine such an effect on GFP expression and fluorescence. Upon modification of one of the two putative OmpT cleavage sites of GFP, we observed several folds enhanced fluorescence of GFP as compared to unmodified GFPuv (Wild Type-WT. The western blot studies of the WT and the SDM II GFP mutant using anti-GFP antibody showed prominent degradation of GFP with negligible degradation in case of SDM II GFP mutant while no such degradation of GFP was seen for both the clones when expressed in BL21 cells. The SDM II GFP mutant also showed enhanced GFP fluorescence in other E. coli K12 OmpT hosts like E. coli JM109 and LE 392 in comparison to WT GFPuv. Inclusion of an OmpT inhibitor, like zinc with WT GFP lysate expressed from an E. coli K12 host was found to reduce degradation of GFP fluorescence by two fold. Results We describe the construction of two GFP variants with modified putative OmpT proteolytic sites by site directed mutagenesis (SDM. Such modified genes upon arabinose induction exhibited varied degrees of GFP fluorescence. While the mutation of K79G/R80A (SDM I resulted in dramatic loss of fluorescence activity, the modification of K214A/R215A (SDM II resulted in four fold enhanced fluorescence of GFP. Conclusions This is the first report on effect of OmpT protease site modification on GFP fluorescence. The wild type and the GFP variants showed similar growth profile in bioreactor studies

  1. Enhancement of mechanical properties and interfacial adhesion by chemical odification of natural fibre reinforced polypropylene composites

    CSIR Research Space (South Africa)

    Erasmus, E

    2008-11-01

    Full Text Available Natural fibres are often used for reinforcing thermoplastics, like polypropylene, to manufacture composite materials exhibiting numerous advantages such as high mechanical properties, low density and biodegradability. The mechanical properties of a...

  2. Enhanced photocatalytic properties of ZnO/reduced graphene oxide sheets (rGO) composites with controllable morphology and composition

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Yanting, E-mail: 928221565@qq.com; Liu, Lin, E-mail: llspzjnu@163.com; Cui, Tingting, E-mail: wuleiwangyou@163.com; Tong, Guoxiu, E-mail: tonggx@zjnu.cn; Wu, Wenhua, E-mail: tongwu@zjnu.cn

    2017-08-01

    Highlights: • An easy one-step low-temperature chemical etching route for ZnO NR/rGO composites. • Modulation over the ZnO morphology and content in ZnO NR/rGO composites. • Investigating shape and content-dependent optical and photocatalytic properties. • Revealing the enhancement mechanism of optical and photocatalytic properties. - Abstract: ZnO with various morphologies and contents was used to decorate reduced graphene oxide (rGO) sheets via an easy one-step low-temperature chemical etching route to improve photocatalytic properties. The ZnO shape and content in ZnO/rGO composites were adjusted by changing aging time, heating mode, and rGO mass added. Shape and content-dependent optical and photocatalytic properties are observed in ZnO/rGO composites. A moderate amount of ZnO nanorings (NRs) decorated with rGO can significantly improve the light absorption and photo-luminescence emission because of plasmonic resonant absorption and plasmonic nanoantenna radiation, respectively. ZnO NR/rGO composites with a moderate ZnO content of 29.54 wt.% exhibit the optimum photocatalytic activity with a 0.025 min{sup −1} apparent rate constant, which is significantly higher than those of pure rGO (0.0085 min{sup −1}) and ZnO NRs (0.018 min{sup −1}). The improved performance is ascribed to the synergistic effect of enhanced adsorption capacity, plasmonic light absorption, plasmonic nanoantenna radiation, and the prolonged lifetime of photogenerated electron-hole pairs. Our findings not only offer insights into the plasmon enhanced optical and photocatalytic properties of ZnO NR/rGO composites but also suggest the possibility of fabricating ZnO NR/rGO photocatalyst with enhanced performance.

  3. NNRTIs: pharmacological data.

    Science.gov (United States)

    Dellamonica, P; Di Perri, G; Garraffo, R

    2012-07-01

    One of the choice criteria for antiretroviral therapy, once the viral load is controlled, is long-term treatment safety. Safety, despite similarities in each therapeutic class, can differ significantly from one agent to another, according to their respective pharmacokinetic and pharmacodynamic properties. We reviewed data on two very well-known NNRTIs, efavirenz and nevirapine, in this context. The pharmacokinetic properties of both agents are presented along with their impact on residual viremia and viral reservoirs, as well as their clinical consequences. The implications for the penetration of these antiretroviral drugs in the CNS and in female and male genital tracts are also discussed. Pharmacogenetics could become an interesting tool. Finally, the availability of new NNRTIs has recently boosted this therapeutic class, even if their long-term properties remain to be assessed. The consideration of all this data stresses the importance of communication among clinicians, virologists, and pharmacologists before choosing a treatment. Copyright © 2012 Elsevier Masson SAS. All rights reserved.

  4. Pharmacologic agents for mucus clearance in bronchiectasis.

    Science.gov (United States)

    Nair, Girish B; Ilowite, Jonathan S

    2012-06-01

    There are no approved pharmacologic agents to enhance mucus clearance in non-cystic fibrosis (CF) bronchiectasis. Evidence supports the use of hyperosmolar agents in CF, and studies with inhaled mannitol and hypertonic saline are ongoing in bronchiectasis. N-acetylcysteine may act more as an antioxidant than a mucolytic in other lung diseases. Dornase α is beneficial to patients with CF, but is not useful in patients with non-CF bronchiectasis. Mucokinetic agents such as β-agonists have the potential to improve mucociliary clearance in normals and many disease states, but have not been adequately studied in patients with bronchiectasis. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. Investigation into stereoselective pharmacological activity of phenotropil.

    Science.gov (United States)

    Zvejniece, Liga; Svalbe, Baiba; Veinberg, Grigory; Grinberga, Solveiga; Vorona, Maksims; Kalvinsh, Ivars; Dambrova, Maija

    2011-11-01

    Phenotropil [N-carbamoylmethyl-4-aryl-2-pyrrolidone (2-(2-oxo-4-phenyl-pyrrolidin-1-yl) acetamide; carphedon)] is clinically used in its racemic form as a nootropic drug that improves physical condition and cognition. The aim of this study was to compare the stereoselective pharmacological activity of R- and S-enantiomers of phenotropil in different behavioural tests. Racemic phenotropil and its enantiomers were tested for locomotor, antidepressant and memory-improving activity and influence on the central nervous system (CNS) using general pharmacological tests in mice. After a single administration, the amount of compound in brain tissue extracts was determined using an ultra performance liquid chromatography-tandem mass spectrometry (UPLC/MS/MS) method in a positive ion electrospray mode. In the open-field test, a significant increase in locomotor activity was observed after a single administration of R-phenotropil at doses of 10 and 50 mg/kg and S-phenotropil at a dose of 50 mg/kg. In the forced swim test, R-phenotropil induced an antidepressant effect at doses of 100 and 50 mg/kg, and S-phenotropil was active at a dose of 100 mg/kg. R-phenotropil significantly enhanced memory function in a passive avoidance response test at a dose of 1 mg/kg; the S-enantiomer did not show any activity in this test. However, the concentrations of R- and S-phenotropils in brain tissue were similar. In conclusion, the antidepressant and increased locomotor activity relies on both R- and S-phenotropils, but the memory-improving activity is only characteristic of R-phenotropil. These results may be important for the clinical use of optically pure isomers of phenotropil. © 2011 The Authors. Basic & Clinical Pharmacology & Toxicology © 2011 Nordic Pharmacological Society.

  6. NASA 2010 Pharmacology Evidence Review

    Science.gov (United States)

    Steinberg, Susan

    2011-01-01

    In 2008, the Institute of Medicine reviewed NASA's Human Research Program Evidence in assessing the Pharmacology risk identified in NASA's Human Research Program Requirements Document (PRD). Since this review there was a major reorganization of the Pharmacology discipline within the HRP, as well as a re-evaluation of the Pharmacology evidence. This panel is being asked to review the latest version of the Pharmacology Evidence Report. Specifically, this panel will: (1) Appraise the descriptions of the human health-related risk in the HRP PRD. (2) Assess the relevance and comprehensiveness of the evidence in identifying potential threats to long-term space missions. (3) Assess the associated gaps in knowledge and identify additional areas for research as necessary.

  7. Pharmacological FMRI: principles and confounds

    OpenAIRE

    Wise, Richard

    2017-01-01

    Talk from the 23 & 24 January 2012 "GlaxoSmithKline - Neurophysics Workshop on Pharmacological MRI", an activity hosted at Warwick University and coordinated with the Neurophysics Marie Curie Initial Training Network of which GSK is a participant.

  8. Light-induced symmetry breaking and related giant enhancement of nonlinear properties in CdZnTe:V crystals.

    Science.gov (United States)

    Shwartz, Sharon; Weil, Raoul; Segev, Mordechai; Lakin, Eugene; Zolotoyabko, Emil; Menon, Vinod M; Forrest, Stephen R; El-Hanany, Uri

    2006-10-02

    We report on enormous light-induced reversible strain effects in CdZnTe:V crystals, which lead to a remarkable enhancement of their nonlinear properties, such as electrostriction and electro-optic effects. Using both high resolution x-ray diffraction and optical interferometry we measure light-induced relative deformation of the initial crystalline lattice (changes in d-spacings) up to 0.15%. The experimental findings are attributed to light-induced breaking of the initial cubic crystalline symmetry. Our results point to a family of inorganic materials whose nonlinear properties can be remarkably enhanced by light, offering new possibilities for nonlinear frequency conversion, generation of Terahertz radiation, electro-optic modulation, and self-deflection of optical beams.

  9. Enhancement of surface plasmon resonances on the nonlinear optical properties in a GaAs quantum dot

    Science.gov (United States)

    Jiang, Xiancong; Guo, Kangxian; Liu, Guanghui; Yang, Tao; Yang, Yanlian

    2017-05-01

    In this paper, the nonlinear optical properties of a metallic nanoparticle (MNP)-semiconductor quantum dot (SQD) hybrid nanosystem with the hybrid exciton effect have been studied. Considering the influence of quantum-size effect to the dielectric function of MNP, the quantum corrected dielectric function was applied to our calculation. By using the compact-density-matrix method, the interaction between MNP and SQD has been studied theoretically. The results show that the surface plasmon resonances (SPRs) of MNP enhance indeed the nonlinear optical properties of SQD. Further more, the enhancement depends on two factors: (a) the center-to-center 7distance between MNP and SQD; (b) the radius ratio between MNP and SQD.

  10. Clinical pharmacology of Cilomilast.

    Science.gov (United States)

    Down, Geoff; Siederer, Sarah; Lim, Sam; Daley-Yates, Peter

    2006-01-01

    renal or hepatic impairment, but concentrations of unbound cilomilast increased with declining renal or hepatic function. Cilomilast had no clinically relevant interactions with a range of drugs likely to be coadministered to patients with COPD, with the exception of erythromycin where concurrent administration with cilomilast was associated with an increased incidence of gastrointestinal adverse events, a pharmacodynamic interaction predicted by their secondary pharmacology. Nausea was the principal adverse reaction seen in healthy subjects taking cilomilast, but this was reduced by administration with food or by use of simple dose-escalation regimens. Cilomilast has not shown a propensity for any of the serious cardiac or neurological adverse effects associated with theophylline. Cilomilast exhibits favourable and predictable pharmacokinetics, has few clinically relevant drug-drug interactions and has demonstrated effects on measures of inflammation of potential benefit in the treatment of COPD. It is generally well tolerated and has not generated safety concerns in any clinical study.

  11. Enhancing Electrophoretic Display Lifetime: Thiol-Polybutadiene Evaporation Barrier Property Response to Network Microstructure

    Energy Technology Data Exchange (ETDEWEB)

    Cook, Caitlyn Christian [California State Polytechnic State Univ., San Luis Obispo, CA (United States)

    2017-02-27

    An evaporation barrier is required to enhance the lifetime of electrophoretic deposition (EPD) displays. As EPD functions on the basis of reversible deposition and resuspension of colloids suspended in a solvent, evaporation of the solvent ultimately leads to device failure. Incorporation of a thiol-polybutadiene elastomer into EPD displays enabled display lifetime surpassing six months in counting and catalyzed rigid display transition into a flexible package. Final flexible display transition to mass production compels an electronic-ink approach to encapsulate display suspension within an elastomer shell. Final thiol-polybutadiene photosensitive resin network microstructure was idealized to be dense, homogeneous, and expose an elastic response to deformation. Research at hand details an approach to understanding microstructural change within display elastomers. Polybutadiene-based resin properties are modified via polymer chain structure, with and without added aromatic urethane methacrylate difunctionality, and in measuring network response to variation in thiol and initiator concentration. Dynamic mechanical analysis results signify that cross-linked segments within a difunctionalized polybutadiene network were on average eight times more elastically active than that of linked segments within a non-functionalized polybutadiene network. Difunctionalized polybutadiene samples also showed a 2.5 times greater maximum elastic modulus than non-functionalized samples. Hybrid polymer composed of both polybutadiene chains encompassed TE-2000 stiffness and B-1000 elasticity for use in encapsulating display suspension. Later experiments measured kinetic and rheological response due to alteration in dithiol cross-linker chain length via real time Fourier transform infrared spectroscopy and real-time dynamic rheology. Distinct differences were discovered between dithiol resin systems, as maximum thiol conversion achieved in short and long chain length dithiols was 86% and

  12. Pharmacologic differences between beta blockers.

    Science.gov (United States)

    Wood, A J

    1984-10-01

    All of the beta blockers act by antagonizing the actions of the endogenous adrenergic agonists epinephrine and norepinephrine at the beta-adrenergic receptors. However, a number of pharmacologic differences exist between the various agents. Some drugs, such as atenolol and metoprolol, are relatively selective for the beta-1-adrenergic receptors, requiring higher concentrations to block beta-2-adrenergic receptors than are required to block beta-1 receptors. It should be noted, however, that these selective beta blockers all block beta-2 receptors when their concentrations are high enough. When patients with asthma must receive a beta blocker, low doses of a selective drug should be used. Recent studies, however, have suggested that the use of a nonselective beta blocker may be desirable to antagonize some beta-2-mediated metabolic effects, such as hypokalemia, induced by epinephrine. Pindolol is the only beta-receptor antagonist available in the United States with intrinsic sympathomimetic, or partial agonist, activity. Such drugs, because of their partial agonist activity, cause some sympathetic stimulation under conditions of low endogenous sympathetic tone, such as while subjects are at rest in the supine position. Under conditions of higher sympathetic tone, pindolol blocks the effects of the endogenous agonists, producing the characteristic effects of a beta blocker. Membrane-stabilizing activity was first recognized with propranolol, and the value of this property has been a source of controversy ever since, but recent studies suggest that propranolol may induce electrophysiologic effects by mechanisms other than beta blockade. Pharmacokinetic differences between the drugs are also of importance.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Polymers for enhanced oil recovery : A paradigm for structure-property relationship in aqueous solution

    NARCIS (Netherlands)

    Wever, D. A. Z.; Picchioni, F.; Broekhuis, A. A.

    2011-01-01

    Recent developments in the field of water-soluble polymers aimed at enhancing the aqueous solution viscosity are reviewed. Classic and novel associating water-soluble polymers for enhanced oil recovery (EOR) applications are discussed along with their limitations. Particular emphasis is placed on

  14. Enhanced

    Directory of Open Access Journals (Sweden)

    Martin I. Bayala

    2014-06-01

    Full Text Available Land Surface Temperature (LST is a key parameter in the energy balance model. However, the spatial resolution of the retrieved LST from sensors with high temporal resolution is not accurate enough to be used in local-scale studies. To explore the LST–Normalised Difference Vegetation Index relationship potential and obtain thermal images with high spatial resolution, six enhanced image