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Sample records for versatile skin bioactive

  1. Tropoelastin - a versatile, bioactive assembly module

    PubMed Central

    Wise, Steven G.; Yeo, Giselle C.; Hiob, Matti A.; Rnjak-Kovacina, Jelena; Kaplan, David L.; Ng, Martin K. C.; Weiss, Anthony S.

    2013-01-01

    Elastin provides structural integrity, biological cues and persistent elasticity to a range of important tissues including the vasculature and lungs. Its critical importance to normal physiology makes it a desirable component of biomaterials that seek to repair or replace these tissues. The recent availability of large quantities of the highly purified elastin monomer, tropoelastin, have allowed for a thorough characterization of the mechanical and biological mechanisms underpinning the benefits of mature elastin. While tropoelastin is a flexible molecule, a combination of optical and structural analyses has defined key regions of the molecule that directly contribute to the elastomeric properties and control the cell interactions of the protein. Insights into the structure and behavior of tropoelastin have translated into increasingly sophisticated elastin-like biomaterials, evolving from classically manufactured hydrogels and fibers to new forms, stabilized in the absence of incorporated cross-linkers. Tropoelastin is also compatible with synthetic and natural co-polymers, expanding the applications of its potential use beyond traditional elastin-rich tissues and facilitating finer control of biomaterial properties and the design of next-generation tailored bioactive materials. PMID:23938199

  2. A Versatile Method for Functionalizing Surfaces with Bioactive Glycans

    PubMed Central

    Cheng, Fang; Shang, Jing; Ratner, Daniel M.

    2011-01-01

    Microarrays and biosensors owe their functionality to our ability to display surface-bound biomolecules with retained biological function. Versatile, stable, and facile methods for the immobilization of bioactive compounds on surfaces have expanded the application of high-throughput ‘omics’-scale screening of molecular interactions by non-expert laboratories. Herein, we demonstrate the potential of simplified chemistries to fabricate a glycan microarray, utilizing divinyl sulfone (DVS)-modified surfaces for the covalent immobilization of natural and chemically derived carbohydrates, as well as glycoproteins. The bioactivity of the captured glycans was quantitatively examined by surface plasmon resonance imaging (SPRi). Composition and spectroscopic evidence of carbohydrate species on the DVS-modified surface were obtained by X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectrometry (ToF-SIMS), respectively. The site-selective immobilization of glycans based on relative nucleophilicity (reducing sugar vs. amine- and sulfhydryl-derived saccharides) and anomeric configuration was also examined. Our results demonstrate straightforward and reproducible conjugation of a variety of functional biomolecules onto a vinyl sulfone-modified biosensor surface. The simplicity of this method will have a significant impact on glycomics research, as it expands the ability of non-synthetic laboratories to rapidly construct functional glycan microarrays and quantitative biosensors. PMID:21142056

  3. Growth Factor-Bearing Polymer Brushes--Versatile Bioactive Substrates Influencing Cell Response.

    PubMed

    Psarra, Evmorfia; Foster, Elena; Knig, Ulla; You, Jungmok; Ueda, Yuichiro; Eichhorn, Klaus-J; Mller, Martin; Stamm, Manfred; Revzin, Alexander; Uhlmann, Petra

    2015-11-01

    In this study we present the development of responsive nanoscale substrates exhibiting cell-guiding properties based on incorporated bioactive signaling cues. The investigative approach considered the effect of two different surface-bound growth factors (GFs) on cell behavior and response: hepatocyte growth factor (HGF) and basic fibroblast growth factor (bFGF). Two surface biofunctionalization strategies were explored in order to conceive versatile, bioactive thin polymer brush films. Polymer brushes made of tethered poly(acrylic)acid (PAA) polymer layers with a high grafting density of polymer chains were biofunctionalized with GFs either by physisorption or chemisorption. Both GFs showed high binding efficiencies to PAA brushes based on their initial loading concentrations. The GF release kinetics can be distinguished depending on the applied biofunctionalization method. Specifically, a high initial burst followed by a constant slow release was observed in the case of both physisorbed HGF and bFGF. In contrast, the release kinetics of chemisorbed GFs were quite different. Remarkably, chemisorbed HGF remained bound to the brush surface for over 1 week, whereas 50% of chemisorbed bFGF was released slowly. Furthermore, the effect of these GF-biofunctionalized PAA brushes on different cells was investigated. A human hepatoma cell line (HepG2) was used to analyze the bioactivity of HGF-modified PAA brushes by measuring cell growth inhibition and scattering effects. Additionally, the differentiation of mouse embryonic stem cells (mESCs) toward endoderm was studied on bFGF-modified PAA brush surfaces. Finally, the results illustrate that PAA brushes, particularly those biofunctionalized with chemisorbed GFs, produce an expected measurable effect on both cell types. Therefore, PAA polymer brushes biofunctionalized with GFs can be used as bioactive cell culture substrates with tuned efficiency. PMID:26447354

  4. Diphenylthiourea, a common rubber chemical, is bioactivated to potent skin sensitizers.

    PubMed

    Samuelsson, Kristin; Bergstrm, Moa Andresen; Jonsson, Charlotte A; Westman, Gunnar; Karlberg, Ann-Therese

    2011-01-14

    Diphenylthiourea (DPTU) is a known skin sensitizer commonly used as a vulcanization accelerator in the production of synthetic rubber, for example, neoprene. The versatile usage of neoprene is due to the multifaceted properties of the material; for example, it is stretchable, waterproof, and chemical- and abrasion-resistant. The wide application of neoprene has resulted in numerous case reports of dermatitis patients allergic to DPTU. The mechanism by which DPTU works as a contact allergen has not been described; thus, the aim of the present study was to investigate if DPTU is a prohapten that can be activated by skin metabolism. The metabolic activation and covalent binding of (14)C-labeled DPTU to proteins were tested using a skinlike cytochrome P450 (P450) cocktail containing the five most abundant P450s found in human skin (CYP1A1, 1B1, 2B6, 2E1, and 3A5) and human liver microsomes. The incubations were carried out in the presence or absence of the metabolite trapping agents glutathione, methoxylamine, and benzylamine. The metabolism mixtures were analyzed by LC-radiochromatography, LC-MS, and LC-MS/MS. DPTU was mainly metabolically activated to reactive sulfoxides resulting in desulfurated adducts in both enzymatic systems used. Also, phenylisothiocyanate and phenylisocyanate were found to be metabolites of DPTU. The sensitizing capacity of the substrate (DPTU) and three metabolites was tested in the murine local lymph node assay. Two out of three metabolites tested were strong skin sensitizers, whereas DPTU itself, as previously known, was negative using this mouse model. In conclusion, DPTU forms highly reactive metabolites upon bioactivation by enzymes present in the skin. These metabolites are able to induce skin sensitization and are probable causes for DPTU allergy. To increase the possibilities of diagnosing contact allergy to DPTU-containing items, we suggest that suitable metabolites of DPTU should be used for screening testing. PMID:21073181

  5. Bioactive compounds from natural resources against skin aging.

    PubMed

    Mukherjee, Pulok K; Maity, Niladri; Nema, Neelesh K; Sarkar, Birendra K

    2011-12-15

    Skin aging involves degradation of extracellular matrix (ECM) in both the epidermal and dermal layers, it leaves visible signs on the surface of skin and the physical properties of the skin are modified. Chronological aging is due to passage of time, whereas premature aging occurred due to some environmental factors on skin produces visible signs such as irregular dryness, dark/light pigmentation, sallowness, severe atrophy, telangiectases, premalignant lesions, laxity, leathery appearance and deep wrinkling. There are several synthetic skincare cosmetics existing in the market to treat premature aging and the most common adverse reactions of those include allergic contact dermatitis, irritant contact dermatitis, phototoxic and photo-allergic reactions. Recent trends in anti-aging research projected the use of natural products derived from ancient era after scientific validation. Ample varieties of phytomolecules such as aloin, ginsenoside, curcumin, epicatechin, asiaticoside, ziyuglycoside I, magnolol, gallic acid, hydroxychavicol, hydroxycinnamic acids, hydroxybenzoic acids, etc. scavenges free radicals from skin cells, prevent trans-epidermal water loss, include a sun protection factor (SPF) of 15 or higher contribute to protect skin from wrinkles, leading to glowing and healthy younger skin. Present era of treating aging skin has become technologically more invasive; but herbal products including botanicals are still relevant and combining them with molecular techniques outlined throughout this review will help to maximize the results and maintain the desired anti-skin aging benefits. PMID:22115797

  6. Simultaneous Delivery of Highly Diverse Bioactive Compounds from Blend Electrospun Fibers for Skin Wound Healing.

    PubMed

    Peh, Priscilla; Lim, Natalie Sheng Jie; Blocki, Anna; Chee, Stella Min Ling; Park, Heyjin Chris; Liao, Susan; Chan, Casey; Raghunath, Michael

    2015-07-15

    Blend emulsion electrospinning is widely perceived to destroy the bioactivity of proteins, and a blend emulsion of water-soluble and nonsoluble molecules is believed to be thermodynamically unstable to electrospin smoothly. Here we demonstrate a method to retain the bioactivity of disparate fragile biomolecules when electrospun. Using bovine serum albumin as a carrier protein; water-soluble vitamin C, fat soluble vitamin D3, steroid hormone hydrocortisone, peptide hormone insulin, thyroid hormone triiodothyronine (T3), and peptide epidermal growth factor (EGF) were simultaneously blend-spun into PLGA-collagen nanofibers. Upon release, vitamin C maintained the ability to facilitate Type I collagen secretion by fibroblasts, EGF stimulated skin fibroblast proliferation, and insulin potentiated adipogenic differentiation. Transgenic cell reporter assays confirmed the bioactivity of vitamin D3, T3, and hydrocortisone. These factors concertedly increased keratinocyte and fibroblast proliferation while maintaining keratinocyte basal state. This method presents an elegant solution to simultaneously deliver disparate bioactive biomolecules for wound healing applications. PMID:26079091

  7. Discovering New Bioactive Neuropeptides in the Striatum Secretome Using in Vivo Microdialysis and Versatile Proteomics S?

    PubMed Central

    Bernay, Benot; Gaillard, Marie-Claude; Gury?a, Vilm; Emadali, Anouk; Kuhn, Lauriane; Bertrand, Anne; Detraz, Isabelle; Carcenac, Carole; Savasta, Marc; Brouillet, Emmanuel; Garin, Jrme; Elalouf, Jean-Marc

    2009-01-01

    The striatum, a major component of the brain basal nuclei, is central for planning and executing voluntary movements and undergoes lesions in neurodegenerative disorders such as Huntington disease. To perform highly integrated tasks, the striatum relies on a complex network of communication within and between brain regions with a key role devoted to secreted molecules. To characterize the rat striatum secretome, we combined in vivo microdialysis together with proteomics analysis of trypsin digests and peptidomics studies of native fragments. This versatile approach, carried out using different microdialysis probes and mass spectrometer devices, allowed evidencing with high confidence the expression of 88 proteins and 100 processed peptides. Their secretory pathways were predicted by in silico analysis. Whereas high molecular weight proteins were mainly secreted by the classical mode (94%), low molecular weight proteins equally used classical and non-classical modes (53 and 47%, respectively). In addition, our results suggested alternative secretion mechanisms not predicted by bioinformatics tools. Based on spectrum counting, we performed a relative quantification of secreted proteins and peptides in both basal and neuronal depolarization conditions. This allowed detecting a series of neuropeptide precursors and a 6-fold increase for neurosecretory protein VGF and proenkephalin (PENK) levels. A focused investigation and a long peptide experiment led to the identification of new secreted non-opioid PENK peptides, referred to as PENK 114133, PENK 239260, and PENK 143185. Moreover we showed that injecting synthetic PENK 114133 and PENK 239260 into the striatum robustly increased glutamate release in this region. Thus, the combination of microdialysis and versatile proteomics methods shed new light on the secreted protein repertoire and evidenced novel neuropeptide transmitters. PMID:19164277

  8. Cocoa Bioactive Compounds: Significance and Potential for the Maintenance of Skin Health

    PubMed Central

    Scapagnini, Giovanni; Davinelli, Sergio; Di Renzo, Laura; De Lorenzo, Antonino; Olarte, Hector Hugo; Micali, Giuseppe; Cicero, Arrigo F.; Gonzalez, Salvador

    2014-01-01

    Cocoa has a rich history in human use. Skin is prone to the development of several diseases, and the mechanisms in the pathogenesis of aged skin are still poorly understood. However, a growing body of evidence from clinical and bench research has begun to provide scientific validation for the use of cocoa-derived phytochemicals as an effective approach for skin protection. Although the specific molecular and cellular mechanisms of the beneficial actions of cocoa phytochemicals remain to be elucidated, this review will provide an overview of the current literature emphasizing potential cytoprotective pathways modulated by cocoa and its polyphenolic components. Moreover, we will summarize in vivo studies showing that bioactive compounds of cocoa may have a positive impact on skin health. PMID:25116848

  9. Cocoa bioactive compounds: significance and potential for the maintenance of skin health.

    PubMed

    Scapagnini, Giovanni; Davinelli, Sergio; Di Renzo, Laura; De Lorenzo, Antonino; Olarte, Hector Hugo; Micali, Giuseppe; Cicero, Arrigo F; Gonzalez, Salvador

    2014-08-01

    Cocoa has a rich history in human use. Skin is prone to the development of several diseases, and the mechanisms in the pathogenesis of aged skin are still poorly understood. However, a growing body of evidence from clinical and bench research has begun to provide scientific validation for the use of cocoa-derived phytochemicals as an effective approach for skin protection. Although the specific molecular and cellular mechanisms of the beneficial actions of cocoa phytochemicals remain to be elucidated, this review will provide an overview of the current literature emphasizing potential cytoprotective pathways modulated by cocoa and its polyphenolic components. Moreover, we will summarize in vivo studies showing that bioactive compounds of cocoa may have a positive impact on skin health. PMID:25116848

  10. Pilot study on the bioactivity of vitamin d in the skin after oral supplementation.

    PubMed

    Curiel-Lewandrowski, Clara; Tang, Jean Y; Einspahr, Janine G; Bermudez, Yira; Hsu, Chiu Hsieh; Rezaee, Melika; Lee, Alex H; Tangrea, Joseph; Parnes, Howard L; Alberts, David S; Chow, H-H Sherry

    2015-06-01

    Laboratory studies suggest that vitamin D (VD) supplementation inhibits skin carcinogenesis. However, epidemiologic studies report mixed findings in the association between circulating VD levels and skin cancer risk. We conducted a clinical study to determine whether oral cholecalciferol supplementation would exert direct bioactivity in human skin through modulation of the VD receptor (VDR). We enrolled 25 individuals with serum 25-hydroxyvitamin-D levels <30 ng/mL and with skin photodamage to take 50,000 IU of cholecalciferol biweekly for 8 to 9 weeks. Then, we obtained baseline and end-of-study skin biopsies from photodamaged (PD) and photoprotected (PP) skin, and from benign nevi (BN) and tested for mRNA expression of VDR and cytochrome P450-24 (CYP24), and markers of keratinocytic differentiation. High-dose cholecalciferol supplementation significantly elevated circulating levels of 25-hydroxyvitamin-D (P < 0.0001) and 1,25-dihydroxyvitamin-D (P < 0.0001). VDR expression in PD- and PP-skin showed minimum changes after supplementation. CYP24 expression in PD- and PP-skin was increased after supplementation by 186%, P = 0.08, and 134%, P = 0.07, respectively. In BNs from 11 participants, a trend for higher VDR and CYP24 expression was observed (average of 20%, P = 0.08, and 544%, P = 0.09, respectively). Caspase-14 expression at the basal layer in PD skin samples was the only epidermal differentiation marker that was significantly increased (49%, P < 0.0001). High-dose cholecalciferol supplementation raised serum VD metabolite levels concurrently with CYP24 mRNA and caspase-14 levels in the skin. Our findings of significant variability in the range of VDR and CYP24 expression across study samples represent an important consideration in studies evaluating the role of VD as a skin cancer chemopreventive agent. PMID:25835512

  11. Epigenetic Alterations in Ultraviolet Radiation-Induced Skin Carcinogenesis: Interaction of Bioactive Dietary Components on Epigenetic Targets†

    PubMed Central

    Katiyar, Santosh K.; Singh, Tripti; Prasad, Ram; Sun, Qian; Vaid, Mudit

    2011-01-01

    The importance of epigenetic alterations in the development of various diseases including the cancers has been realized. As epigenetic changes are reversible heritable changes, these can be utilized as an effective strategy for the prevention of cancers. DNA methylation is the most characterized epigenetic mechanism that can be inherited without changing the DNA sequence. Although limited, but available data suggest that silencing of tumor suppressor genes in ultraviolet (UV) radiation-exposed epidermis leads to photocarcinogenesis and is associated with a network of epigenetic modifications including alterations in DNA methylation, DNA methyltransferases and histone acetylations. Various bioactive dietary components have been shown to protect skin from UV radiation-induced skin tumors in animal models. The role of bioactive dietary components, such as, (−)-epicatechins from green tea and proanthocyanidins from grape seeds, has been assessed in chemoprevention of UV-induced skin carcinogenesis and underlying epigenetic mechanism in vitro and in vivo animal models. These bioactive components have the ability to block UV-induced DNA hypermethylation and histone modifications in the skin required for the silencing of tumor suppressor genes (e.g., Cip1/p21, p16INK4a). These information are of importance for understanding the role of epigenetic modulation in UV-induced skin tumor and the chemopreventive mechanism of bioactive dietary components. PMID:22017262

  12. House dust bioactivities predict skin prick test reactivity for children with high risk of allergy

    PubMed Central

    Kim, Haejin; Tse, Kevin; Levin, Linda; Bernstein, David; Reponen, Tiina; LeMasters, Grace; Lummus, Zana; Horner, Anthony A.

    2013-01-01

    Background Although evidence suggests that ambient exposures to endotoxin and other immunostimulants during early life influence allergic risk, efforts to understand this host-environment relationship have been hampered by a paucity of relevant assays. Objectives These investigations determined whether parameters of house dust extract (HDE) bioactivity were predictive of allergen skin prick test (SPT) reactivity for infants at high risk of allergy participating in the Cincinnati Childhood Allergy and Air Pollution Study (CCAAPS). Methods We conducted a nested case-control study, selecting 99 CCAAPS children who had positive SPT results to at least 1 aeroallergen at age 3 years and 101 subjects with negative SPT results. HDEs were prepared from dust samples collected from the subjects' homes at age 1 year. Murine splenocytes and bone marrowderived dendritic cells were incubated with HDEs, and supernatant cytokine concentrations were determined by means of ELISA. Alternatively, bone marrowderived dendritic cells were preincubated with HDEs, and then LPS-induced IL-6 responses were assessed. HDE endotoxin levels were determined by using the limulus amebocyte lysate assay. Results HDEs derived from the homes of children with positive (cases) and negative (control subjects) SPT results had similar bioactivities. However, when cases were considered in isolation, HDEs with higher levels of bioactivity were significantly associated with children who had lower numbers of positive SPT results. Analogous statistical analyses did not identify any association between HDE endotoxin levels and the aeroallergen sensitization profiles of children included in this study. Conclusion HDE immunostimulatory activities predicted the aeroallergen sensitization status of CCAAPS subjects better than HDE endotoxin levels. These results provide the first published evidence that HDE bioassays have clinical relevance in predicting atopic risk. PMID:22385634

  13. Influence of extraction techniques on antioxidant properties and bioactive compounds of loquat fruit (Eriobotrya japonica Lindl.) skin and pulp extracts.

    PubMed

    Delfanian, Mojtaba; Esmaeilzadeh Kenari, Reza; Sahari, Mohammad Ali

    2015-05-01

    In this study, the bioactive compounds of loquat fruit (Eriobotrya japonica Lindl.) skin and pulp extracted by two extraction methods (solvent and ultrasound-assisted) with three solvents (ethanol, water and ethanol-water) were compared to supercritical fluid extraction. The antioxidant activities of skin and pulp extracts were evaluated and compared to tertiary butylhydroquinone (TBHQ) using 2, 2-diphenyl-1-picrylhydrazyl (DPPH?) radical scavenging, ?-carotene bleaching, and the Rancimat assays. In DPPH assay solvent extracts of skin by ethanol (SSE) and ethanol-water (SSEW) showed strong inhibitory activity. The SSEW also showed the highest inhibition percentage of 85.58% by the ?-carotene bleaching assay and longest induction time of 4.78h by the Rancimat method. The large amount of tocopherols and phenolics contained in the skin extract may cause its strong antioxidant ability. The results indicated that the solvent extraction with ethanol-water produced the maximum extraction yield of phenolic and tocopherol compounds from loquat fruit skin and pulp. Furthermore, solvent extraction was the most effective in antioxidant activity of the extracts compared to other extraction techniques. PMID:25987992

  14. Influence of extraction techniques on antioxidant properties and bioactive compounds of loquat fruit (Eriobotrya japonica Lindl.) skin and pulp extracts

    PubMed Central

    Delfanian, Mojtaba; Esmaeilzadeh Kenari, Reza; Sahari, Mohammad Ali

    2015-01-01

    In this study, the bioactive compounds of loquat fruit (Eriobotrya japonica Lindl.) skin and pulp extracted by two extraction methods (solvent and ultrasound-assisted) with three solvents (ethanol, water and ethanol–water) were compared to supercritical fluid extraction. The antioxidant activities of skin and pulp extracts were evaluated and compared to tertiary butylhydroquinone (TBHQ) using 2, 2-diphenyl-1-picrylhydrazyl (DPPH˙) radical scavenging, β-carotene bleaching, and the Rancimat assays. In DPPH assay solvent extracts of skin by ethanol (SSE) and ethanol–water (SSEW) showed strong inhibitory activity. The SSEW also showed the highest inhibition percentage of 85.58% by the β-carotene bleaching assay and longest induction time of 4.78 h by the Rancimat method. The large amount of tocopherols and phenolics contained in the skin extract may cause its strong antioxidant ability. The results indicated that the solvent extraction with ethanol–water produced the maximum extraction yield of phenolic and tocopherol compounds from loquat fruit skin and pulp. Furthermore, solvent extraction was the most effective in antioxidant activity of the extracts compared to other extraction techniques. PMID:25987992

  15. The impact of grape skin bioactive functionality information on the acceptability of tea infusions made from wine by-products.

    PubMed

    Cheng, Vern Jou; Bekhit, Alaa El-Din A; Sedcole, Richard; Hamid, Nazimah

    2010-05-01

    The effect of information on the health benefits of bio-active compounds on the acceptability of 5 tea infusions made from grape skins generated from wine processing waste (from Vitis vinifera var. Pinot Noir and Pinot Gris) was investigated. Samples of tea infusions with natural additives (PNHGT25 and PGGT50) and without additives (control PN, control PG, and PNPG50) were evaluated by 45 in-home consumer panels (30 female, 15 male) before and after information on the health benefits of grape skins were provided. Information significantly increased the overall acceptability, overall aroma, flavor, and aftertaste of the infusions. The results obtained showed a clear tendency toward increased purchase intention (by 29%) when information on the health benefits of the tea infusion samples was provided to consumers. Interactions existed between gender/infusion samples and stage of information on the purchase intention. Females recorded a significant increase (by 53%) in purchase intention, whereas no change in the males' purchase intention was found after information was provided. PMID:20546418

  16. A review on skin targeted delivery of bioactives as ultradeformable vesicles: overcoming the penetration problem.

    PubMed

    Priyanka, Karunanidhi; Singh, Sanjay

    2014-02-01

    Administration of drugs through skin via transdermal route is a non-invasive approach and applicable for systemic delivery but it is not suitable for drugs having higher molecular weight. Various approaches have been used to improve the efficacy of transdermal route such as vesicular system, iontophoresis, microneedles, use of permeation enhancers, etc. Among the several approaches, vesicular delivery is gaining importance in transdermal drug delivery. Transfersomes are one of the vesicular systems and they are best suited for the transdermal delivery of higher molecular weight compounds. Due to the deformable nature of transfersomes, they penetrate into deeper layers of skin, retain their original structure after penetration and finally enter into the systemic circulation. This review focuses mainly on the applications of transfersomes in the field of drug delivery i.e. delivery of analgesics, anti-cancers, proteins and peptides, immunomodulators, steroidal hormones and herbal drugs with increased penetration through skin. In addition, this review also deals with preparation methods available for preparing transfersomes, characterization, mechanism of penetration upon topical application and its kinetic aspects. PMID:24410447

  17. Permeation of bioactive constituents from Arnica montana preparations through human skin in-vitro.

    PubMed

    Tekko, I A; Bonner, M C; Bowen, R D; Williams, A C

    2006-09-01

    This study investigated and characterised transdermal permeation of bioactive agents from a topically applied Arnica montana tincture. Permeation experiments conducted over 48 h used polydimethylsiloxane (silastic) and human epidermal membranes mounted in Franz-type diffusion cells with a methanol-water (50:50 v/v) receptor fluid. A commercially available tincture of A. montana L. derived from dried Spanish flower heads was a donor solution. Further donor solutions prepared from this stock tincture concentrated the tincture constituents 1, 2 and 10 fold and its sesquiterpene lactones 10 fold. Permeants were assayed using a high-performance liquid chromatography method. Five components permeated through silastic membranes providing peaks with relative retention factors to an internal standard (santonin) of 0.28, 1.18, 1.45, 1.98 and 2.76, respectively. No permeant was detected within 12 h of applying the Arnica tincture onto human epidermal membranes. However, after 12 h, the first two of these components were detected. These were shown by Zimmermann reagent reaction to be sesquiterpene lactones and liquid chromatography/diode array detection/mass spectrometry indicated that these two permeants were 11,13-dihydrohelenalin (DH) analogues (methacrylate and tiglate esters). The same two components were also detected within 3 h of topical application of the 10-fold concentrated tincture and the concentrated sesquiterpene lactone extract. PMID:16945174

  18. Surface functionalization of bioactive glasses with natural molecules of biological significance, part II: Grafting of polyphenols extracted from grape skin

    NASA Astrophysics Data System (ADS)

    Zhang, Xin; Ferraris, Sara; Prenesti, Enrico; Vern, Enrica

    2013-12-01

    Polyphenols, as one of the most important family of phytochemicals protective substances from grape fruit, possess various biological activities and health-promoting benefits, for example: inhibition of some degenerative diseases, cardiovascular diseases and certain types of cancers, reduction of plasma oxidative stress and slowing aging. The combination of polyphenols and biomaterials may have good potential to reach good bioavailability and controlled release, as well as to give biological signaling properties to the biomaterial surfaces. In this research, conventional solvent extraction was developed for obtaining polyphenols from dry grape skins. The Folin&Ciocalteu method was used to determine the amount of total polyphenols in the extracts. Surface functionalization of two bioactive glasses (SCNA and CEL2) was performed by grafting the extracted polyphenols on their surfaces. The effectiveness of the functionalization was tested by UV spectroscopy, which analyzes the amount of polyphenols in the uptake solution (before and after functionalization) and on solid samples, and XPS, which analyzes the presence of phenols on the material surface.

  19. Assessment of Lemon Balm (Melissa officinalis L.) Hydrogels: Quality and Bioactivity in Skin Cells

    PubMed Central

    Ramanauskienė, Kristina; Stelmakiene, Ada; Majienė, Daiva

    2015-01-01

    The aim of the study was to design gels with lemon balm extract, assess their quality, and investigate the effect of rosmarinic acid on skin cells in normal conditions and under oxidative stress. Methods. The quantities of rosmarinic acid (RA) released from gels were evaluated by applying the HPLC technique. HaCaT cell viability was assessed by using the MTT method. ROS generation was measured using DCFH-DA dye. The results showed that the gelling material affected the release of RA content from gels. Lower and slower RA content release was determined in carbomer-based gels. After 6 hours of biopharmaceutical research in vitro, at least 4% of RA was released from the gel. The results of the biological studies on HaCaT cells demonstrated that, in the oxidative stress conditions, RA reduced intracellular ROS amounts to 28%; 0.25–0.5 mg/mL of RA increased cell viability by 10–24% and protected cells from the damage caused by H2O2. Conclusions. According to research results, it is appropriate to use a carbomer as the main gelling material, and its concentration should not exceed 1.0%. RA, depending on the concentration, reduces the amount of intracellular ROS and enhances cell viability in human keratinocytes in oxidative stress conditions. PMID:26600864

  20. Assessment of Lemon Balm (Melissa officinalis L.) Hydrogels: Quality and Bioactivity in Skin Cells.

    PubMed

    Ramanauskien?, Kristina; Stelmakiene, Ada; Majien?, Daiva

    2015-01-01

    The aim of the study was to design gels with lemon balm extract, assess their quality, and investigate the effect of rosmarinic acid on skin cells in normal conditions and under oxidative stress. Methods. The quantities of rosmarinic acid (RA) released from gels were evaluated by applying the HPLC technique. HaCaT cell viability was assessed by using the MTT method. ROS generation was measured using DCFH-DA dye. The results showed that the gelling material affected the release of RA content from gels. Lower and slower RA content release was determined in carbomer-based gels. After 6 hours of biopharmaceutical research in vitro, at least 4% of RA was released from the gel. The results of the biological studies on HaCaT cells demonstrated that, in the oxidative stress conditions, RA reduced intracellular ROS amounts to 28%; 0.25-0.5?mg/mL of RA increased cell viability by 10-24% and protected cells from the damage caused by H2O2. Conclusions. According to research results, it is appropriate to use a carbomer as the main gelling material, and its concentration should not exceed 1.0%. RA, depending on the concentration, reduces the amount of intracellular ROS and enhances cell viability in human keratinocytes in oxidative stress conditions. PMID:26600864

  1. Full-Thickness Skin Wound Healing Using Human Placenta-Derived Extracellular Matrix Containing Bioactive Molecules

    PubMed Central

    Choi, Ji Suk; Kim, Jae Dong; Yoon, Hyun Soo

    2013-01-01

    The human placenta, a complex organ, which facilitates exchange between the fetus and the mother, contains abundant extracellular matrix (ECM) components and well-preserved endogenous growth factors. In this study, we designed a new dermal substitute from human placentas for full-thickness wound healing. Highly porous, decellularized ECM sheets were fabricated from human placentas via homogenization, centrifugation, chemical and enzymatic treatments, molding, and freeze-drying. The physical structure and biological composition of human placenta-derived ECM sheets dramatically supported the regeneration of full-thickness wound in vivo. At the early stage, the ECM sheet efficiently absorbed wound exudates and tightly attached to the wound surface. Four weeks after implantation, the wound was completely closed, epidermic cells were well arranged and the bilayer structure of the epidermis and dermis was restored. Moreover, hair follicles and microvessels were newly formed in the ECM sheet-implanted wounds. Overall, the ECM sheet produced a dermal substitute with similar cellular organization to that of normal skin. These results suggest that human placenta-derived ECM sheets provide a microenvironment favorable to the growth and differentiation of cells, and positive modulate the healing of full-thickness wounds. PMID:22891853

  2. The versatility of a glycerol-preserved skin allograft as an adjunctive treatment to free flap reconstruction.

    PubMed

    Mat Saad, A Z; Khoo, T L; Dorai, A A; Halim, A S

    2009-01-01

    Skin allografts have been used in medical practice for over a century owing to their unique composition as a biological dressing. Skin allografts can be obtained in several preparations such as cryopreserved, glycerol-preserved, and fresh allograft. A glycerol-preserved allograft (GPA) was introduced in the early 1980s. It has several advantages compared with other dressings such as ease of processing, storage and transport, lower cost, less antigenicity, antimicrobial properties, and neo-vascularisation promoting properties. Skin allografts are mainly used in the management of severe burn injuries, chronic ulcers, and complex, traumatic wounds. Published reports of the use of skin allografts in association with free flap surgery are few or non existent. We would like to share our experience of several cases of free tissue transfer that utilised GPA as a temporary wound dressing in multiple scenarios. On the basis of this case series, we would like to recommend that a GPA be used as a temporary dressing in conjunction with free flap surgery when required to protect the flap pedicle, allowing time for the edema to subside and the wound can then be closed for a better aesthetic outcome. PMID:19881027

  3. Characterization of physiochemical and microbiological properties, and bioactive compounds, of flour made from the skin and bagasse of kiwi fruit (Actinidia deliciosa).

    PubMed

    Soquetta, Marcela Bromberger; Stefanello, Flávia Santi; Huerta, Katira da Mota; Monteiro, Sabrina Sauthier; da Rosa, Claudia Severo; Terra, Nelcindo Nascimento

    2016-05-15

    The objective of this study was to analyze the physicochemical and microbiological properties, as well as the bioactive compounds, of flour made from the skin and bagasse of two varieties (Bruno and Monty) of kiwi fruit (Actinidia deliciosa) at two stages of maturation. The flour made with kiwi fruit peel from both varieties showed higher levels of bioactive compounds and antioxidant activity that the flour made with bagasse from both varieties. The flour made with green kiwi fruit skin from the Bruno variety had higher DPPH values and levels of phenolic compounds (1262.34mg GAE/100g flour), while the Monty variety showed higher FRAP values, vitamin C (189.06mg/100g flour), flavonoids (486.47mg/100g flour), chlorophylls (12.13mg/100g flour) and carotenoids (246.91μg/100g flour). Flour made from kiwi fruit bagasse can be used to reduce agro-industrial waste. This flour is a promising ingredient which can be used to enrich products providing dietary fiber and bioactive compounds, as well as antioxidant action. PMID:26775997

  4. Bioactives derived from ripe corn tassels: a possible new natural skin whitener, 4-hydroxy-1-oxindole-3-acetic acid

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previously, we showed that extracts of ripe seasonal sweet corn tassels possess anti-irritant and anti-oxidant activities. The chemical identification of corn tassel bioactives were investigated by HPLC analysis. The hydroalcoholic extracts are composed primarily (>85%) phenolic-type compounds. The ...

  5. Wound dressings composed of copper-doped borate bioactive glass microfibers stimulate angiogenesis and heal full-thickness skin defects in a rodent model.

    PubMed

    Zhao, Shichang; Li, Le; Wang, Hui; Zhang, Yadong; Cheng, Xiangguo; Zhou, Nai; Rahaman, Mohamed N; Liu, Zhongtang; Huang, Wenhai; Zhang, Changqing

    2015-01-01

    There is a need for better wound dressings that possess the requisite angiogenic capacity for rapid in situ healing of full-thickness skin wounds. Borate bioactive glass microfibers are showing a remarkable ability to heal soft tissue wounds but little is known about the process and mechanisms of healing. In the present study, wound dressings composed of borate bioactive glass microfibers (diameter = 0.4-1.2 μm; composition 6Na2O, 8K2O, 8MgO, 22CaO, 54B2O3, 2P2O5; mol%) doped with 0-3.0 wt.% CuO were created and evaluated in vitro and in vivo. When immersed in simulated body fluid, the fibers degraded and converted to hydroxyapatite within ∼7 days, releasing ions such as Ca, B and Cu into the medium. In vitro cell culture showed that the ionic dissolution product of the fibers was not toxic to human umbilical vein endothelial cells (HUVECs) and fibroblasts, promoted HUVEC migration, tubule formation and secretion of vascular endothelial growth factor (VEGF), and stimulated the expression of angiogenic-related genes of the fibroblasts. When used to treat full-thickness skin defects in rodents, the Cu-doped fibers (3.0 wt.% CuO) showed a significantly better capacity to stimulate angiogenesis than the undoped fibers and the untreated defects (control) at 7 and 14 days post-surgery. The defects treated with the Cu-doped and undoped fibers showed improved collagen deposition, maturity and orientation when compared to the untreated defects, the improvement shown by the Cu-doped fibers was not markedly better than the undoped fibers at 14 days post-surgery. These results indicate that the Cu-doped borate glass microfibers have a promising capacity to stimulate angiogenesis and heal full-thickness skin defects. They also provide valuable data for understanding the role of the microfibers in healing soft tissue wounds. PMID:25890736

  6. Fabrication of a nanofibrous scaffold with improved bioactivity for culture of human dermal fibroblasts for skin regeneration.

    TOXLINE Toxicology Bibliographic Information

    Chandrasekaran AR; Venugopal J; Sundarrajan S; Ramakrishna S

    2011-02-01

    Engineering dermal substitutes with electrospun nanofibres have lately been of prime importance for skin tissue regeneration. Simple electrospinning technology served to produce nanofibrous scaffolds morphologically and structurally similar to the extracellular matrix of native tissues. The nanofibrous scaffolds of poly(L-lactic acid)-co-poly(?-caprolactone) (PLACL) and PLACL/gelatin complexes were fabricated by the electrospinning process. These nanofibres were characterized for fibre morphology, membrane porosity, wettability and chemical properties by FTIR analysis to culture human foreskin fibroblasts for skin tissue engineering. The nanofibre diameter was obtained between 282 and 761 nm for PLACL and PLACL/gelatin scaffolds; expressions of amino and carboxyl groups and porosity up to 87% were obtained for these fibres, while they also exhibited improved hydrophilic properties after plasma treatment. The results showed that fibroblasts proliferation, morphology, CMFDA dye expression and secretion of collagen were significantly increased in plasma-treated PLACL/gelatin scaffolds compared to PLACL nanofibrous scaffolds. The obtained results prove that the plasma-treated PLACL/gelatin nanofibrous scaffold is a potential biocomposite material for skin tissue regeneration.

  7. Identification and bioactivity evaluation of a novel bradykinin inhibitory peptide from the skin secretion of Chinese large odorous frog, Odorrana livida.

    PubMed

    Yang, Kundi; Ma, Chengbang; Zhou, Mei; Wang, Lei; Li, Renjie; Chen, Tianbao; Shaw, Chris; Li, Wei

    2016-03-01

    A novel peptide was isolated from the skin secretion of Chinese large odorous frog, Odorrana livida, and was named as Rana-BI. The cDNA sequencing was obtained by 'shotgun' cloning. The amino acid sequence of the mature peptide was identified as Gly-Leu-Leu-Ser-Gly-Lys-Ser-Val-Lys-Gly-Ser-Ile-OH by automated Edman degradation, and the molecular weight of the peptide was confirmed to be 1144.68 Da by MALDI-TOF and liquid chromatography/MS. Subsequently, the bioactivity of synthetic peptide was evaluated by smooth muscle assay using isolated rat bladder preparation. It was demonstrated that Rana-BI inhibited the contraction of rat bladder induced by bradykinin. Comparing with other peptides by searching from database, the primary structure of Rana-BI showed high similarity with that of an antimicrobial peptide of Rana family (12/12 residues). These data revealed a novel biological function of this peptide. Copyright © 2016 European Peptide Society and John Wiley & Sons, Ltd. PMID:26856692

  8. Fibrin: a versatile scaffold for tissue engineering applications.

    PubMed

    Ahmed, Tamer A E; Dare, Emma V; Hincke, Max

    2008-06-01

    Tissue engineering combines cell and molecular biology with materials and mechanical engineering to replace damaged or diseased organs and tissues. Fibrin is a critical blood component responsible for hemostasis, which has been used extensively as a biopolymer scaffold in tissue engineering. In this review we summarize the latest developments in organ and tissue regeneration using fibrin as the scaffold material. Commercially available fibrinogen and thrombin are combined to form a fibrin hydrogel. The incorporation of bioactive peptides and growth factors via a heparin-binding delivery system improves the functionality of fibrin as a scaffold. New technologies such as inkjet printing and magnetically influenced self-assembly can alter the geometry of the fibrin structure into appropriate and predictable forms. Fibrin can be prepared from autologous plasma, and is available as glue or as engineered microbeads. Fibrin alone or in combination with other materials has been used as a biological scaffold for stem or primary cells to regenerate adipose tissue, bone, cardiac tissue, cartilage, liver, nervous tissue, ocular tissue, skin, tendons, and ligaments. Thus, fibrin is a versatile biopolymer, which shows a great potential in tissue regeneration and wound healing. PMID:18544016

  9. Extracellular matrix formation in self-assembled minimalistic bioactive hydrogels based on aromatic peptide amphiphiles

    PubMed Central

    Zhou, Mi; Ulijn, Rein V

    2014-01-01

    The hitherto inconsistency in clinical performance for engineered skin drives the current development of novel cell-scaffolding materials; one challenge is to only extract essential characteristics from the complex native ECM (extracellular matrix) and incorporate them into a scaffold with minimal complexity to support normal cell functions. This study involved small-molecule-based bioactive hydrogels produced by the co-assembly of two aromatic peptide amphiphiles: Fmoc-FF (Fluorenylmethoxycarbonyl-diphenylalanine) and Fmoc-RGD (arginineglycineaspartic acid). Three-dimensionally cultured human dermal fibroblasts deposited dense ECM networks including fibronectin and collagen I within the hydrogels in a 14-day culture. The fibroblasts organized the fibrous ECM and contracted the gel without differentiating into myofibroblasts. The stiffness of the cell-gel constructs increased dramatically due to ECM formation and gel contraction. This created an economical biomimetic model-scaffold to further understand skin reconstruction in vitro and supplied a design pathway to create versatile cell-scaffolds with varied bioactivities and simplicity. PMID:24812581

  10. Versatile communications terminal

    NASA Technical Reports Server (NTRS)

    Belasco, N.; Pool, S. L.; Sinderson, R. L.

    1978-01-01

    Widely-separated parties are linked into efficient communications network by versatile control terminal. Terminal handles voice and data communications via both telephone lines and radio-frequency channels. It includes telephone-to-radio "patch", telephone autodialer, and other advanced features to provide rapid communications for applications such as emergency medical services (EMS) operations.

  11. Fabrication of PEGylated fibrinogen: a versatile injectable hydrogel biomaterial.

    PubMed

    Mironi-Harpaz, Iris; Berdichevski, Alexandra; Seliktar, Dror

    2014-01-01

    Hydrogels are one of the most versatile biomaterials in use for tissue engineering and regenerative medicine. They are assembled from either natural or synthetic polymers, and their high water content gives these materials practical advantages in numerous biomedical applications. Semisynthetic hydrogels, such as those that combine synthetic and biological building blocks, have the added advantage of controlled bioactivity and material properties. In myocardial regeneration, injectable hydrogels premised on a semisynthetic design are advantageous both as bioactive bulking agents and as a delivery vehicle for controlled release of bioactive factors and/or cardiomyocytes. A new semisynthetic hydrogel based on PEGylated fibrinogen has been developed to address the many requirements of an injectable biomaterial in cardiac restoration. This chapter highlights the fundamental aspects of making this biomimetic hydrogel matrix for cardiac applications. PMID:25070327

  12. Versatile, Fast Computer Core

    NASA Technical Reports Server (NTRS)

    Ross, Douglas

    1991-01-01

    Versatile computer core serves as state-of-the-art component and tool for development of computing systems required to process data rapidly, particularly as part of control tasks involving relatively large volumes of input and output data. Exploits new technology to enhance performance needed in flight computers. Computing and other equipment specific to flight system added around this core to develop flight systems rapidly without incurring time and monetary costs of designing new core.

  13. Bioactive peptides: signaling the future.

    PubMed

    Fields, K; Falla, T J; Rodan, K; Bush, L

    2009-03-01

    Natural processes within the body are modulated almost exclusively by the interaction of specific amino acid sequences, either as peptides or as subsections of proteins. With respect to skin, proteins and peptides are involved in the modulation of cell proliferation, cell migration, inflammation, angiogenesis, melanogenesis, and protein synthesis and regulation. The creation of therapeutic or bioactive peptide analogs of specific interactive sequences has opened the door to a diverse new field of pharmaceutical and active cosmetic ingredients for the skincare industry. Here, we describe the origin of such sequences, their role in nature, their application to dermatology, as well as the advantages and challenges posed by this new technology. PMID:19250159

  14. Bioactivation of particles

    DOEpatents

    Pinaud, Fabien (Berkeley, CA); King, David (San Francisco, CA); Weiss, Shimon (Los Angeles, CA)

    2011-08-16

    Particles are bioactivated by attaching bioactivation peptides to the particle surface. The bioactivation peptides are peptide-based compounds that impart one or more biologically important functions to the particles. Each bioactivation peptide includes a molecular or surface recognition part that binds with the surface of the particle and one or more functional parts. The surface recognition part includes an amino-end and a carboxy-end and is composed of one or more hydrophobic spacers and one or more binding clusters. The functional part(s) is attached to the surface recognition part at the amino-end and/or said carboxy-end.

  15. Versatile neutron NDA

    SciTech Connect

    DeVolpi, A.

    1995-07-01

    Non-destructive analysis (NDA) of bulk samples is a major tool in international safeguards and domestic MC&A. Yet, enhancements are needed to reduce inspection time, financial cost, and radiation exposure-while improving reliability and accuracy-particularly for mixtures of fissile and fertile isotopes. Perhaps the greatest remaining direction for NDA improvement is the development of a single controllable neutron source that would add versatility and capability. One of the primary prospects is a switchable radioactive neutron source (SRNS) that has been under advanced-concept development at Argonne with DOE funding. The SRNS would be in a sealed capsule that can be remotely switched on and off, or pulsed at a controllable rate. Li({alpha}, n) or Be({alpha}, n) reactions could give a choice of sub-threshold or hard-spectrum neutrons at yields ranging from 10{sup 4}/s to more than 10{sup 8}s. The SRNS would provide improved capabilities for (1) simultaneous or alternating interrogation with fast and slow neutrons, (2) detection of the first few seconds of delayed neutrons, (3) measurements in the presence of high neutron and/or gamma background, and (4) inspection of heterogeneous materials. When the neutrons are switched off, the source would be portable with vastly reduced shielding. Proof-of-concept with a single switchable plate has been established under laboratory conditions.

  16. A versatile microfiltration device.

    PubMed

    Lenzen, S; Panten, U

    1983-10-01

    A versatile vacuum microfiltration device was designed for separation of small volumes of liquid from samples of cells or subcellular organelles through membrane filters. It is especially useful for separation of small samples from radioactive tracer when low blank values are mandatory for the performance of the measurement. In the present communication the microfiltration device was used for the separation of organelles from incubation medium labeled with 45Ca2+ for measurement of uptake of 45Ca2+ by small samples of liver or pancreatic islet mitochondria or of pancreatic islet secretory granules. Measurement of 45Ca2+ uptake was possible in samples containing less than 1 microgram of protein even if the sample was incubated with only 10,000 cpm of 45CaCl2. Blank values ranged only between 2.6 and 4.7% of the test values. The device should be useful for a variety of applications in many research areas where sample volumes are small. PMID:6362482

  17. Carbapenemases: the Versatile ?-Lactamases

    PubMed Central

    Queenan, Anne Marie; Bush, Karen

    2007-01-01

    Carbapenemases are ?-lactamases with versatile hydrolytic capacities. They have the ability to hydrolyze penicillins, cephalosporins, monobactams, and carbapenems. Bacteria producing these ?-lactamases may cause serious infections in which the carbapenemase activity renders many ?-lactams ineffective. Carbapenemases are members of the molecular class A, B, and D ?-lactamases. Class A and D enzymes have a serine-based hydrolytic mechanism, while class B enzymes are metallo-?-lactamases that contain zinc in the active site. The class A carbapenemase group includes members of the SME, IMI, NMC, GES, and KPC families. Of these, the KPC carbapenemases are the most prevalent, found mostly on plasmids in Klebsiella pneumoniae. The class D carbapenemases consist of OXA-type ?-lactamases frequently detected in Acinetobacter baumannii. The metallo-?-lactamases belong to the IMP, VIM, SPM, GIM, and SIM families and have been detected primarily in Pseudomonas aeruginosa; however, there are increasing numbers of reports worldwide of this group of ?-lactamases in the Enterobacteriaceae. This review updates the characteristics, epidemiology, and detection of the carbapenemases found in pathogenic bacteria. PMID:17630334

  18. Skin Diseases: Skin Health and Skin Diseases

    MedlinePLUS

    ... the sun. Photo: PhotoDisc Care for conditions from acne to wrinkles Did you know that your skin ... other skin conditions. Many skin problems, such as acne, also affect your appearance. Your skin can also ...

  19. Biological Versatility and Earth History

    PubMed Central

    Vermeij, Geerat J.

    1973-01-01

    Examples from various plant and animal groups indicate that there has been a general increase in potential versatility of form, determined by the number and range of independently varying morphogenetic parameters, among taxa appearing at successively younger stages in the fossil record. Taxa or body plans with higher potential versatility have tended to replace less potentially versatile groups in the same or similar adaptive zone through time. Greater potential diversity allows for greater homeostasis, efficiency, and integration of structures and functions, and for an increase in size of the potential adaptive zone. In contrast, chemical versatility has generally decreased within groups from the pre-Cambrian to the Phanerozoic, partly as the result of apparent changes in the chemical environment and partly as the consequence of selection for efficiency and greater metabolic ease of handling of certain materials. PMID:4198660

  20. DVD - digital versatile disks

    SciTech Connect

    Gaunt, R.

    1997-05-01

    An international standard has emerged for the first true multimedia format. Digital Versatile Disk (by its official name), you may know it as Digital Video Disks. DVD has applications in movies, music, games, information CD-ROMS, and many other areas where massive amounts of digital information is needed. Did I say massive amounts of data? Would you believe over 17 gigabytes on a single piece of plastic the size of an audio-CD? That`s the promise, at least, by the group of nine electronics manufacturers who have agreed to the format specification, and who hope to make this goal a reality by 1998. In this major agreement, which didn`t come easily, the manufacturers will combine Sony and Phillip`s one side double-layer NMCD format with Toshiba and Matsushita`s double sided Super-Density disk. By Spring of this year, they plan to market the first 4.7 gigabyte units. The question is: Will DVD take off? Some believe that read-only disks recorded with movies will be about as popular as video laser disks. They say that until the eraseable/writable DVD arrives, the consumer will most likely not buy it. Also, DVD has a good market for replacement of CD- Roms. Back in the early 80`s, the international committee deciding the format of the audio compact disk decided its length would be 73 minutes. This, they declared, would allow Beethoven`s 9th Symphony to be contained entirely on a single CD. Similarly, today it was agreed that playback length of a single sided, single layer DVD would be 133 minutes, long enough to hold 94% of all feature-length movies. Further, audio can be in Dolby`s AC-3 stereo or 5.1 tracks of surround sound, better than CD-quality audio (16-bits at 48kHz). In addition, there are three to five language tracks, copy protection and parental ``locks`` for R rated movies. DVD will be backwards compatible with current CD-ROM and audio CD formats. Added versatility comes by way of multiple aspect rations: 4:3 pan-scan, 4:3 letterbox, and 16:9 widescreen. MPEG-2 is the selected image compression format, with full ITU Rec. 601 video resolution (72Ox480). MPEG-2 and AC-3 are also part of the U.S. high definition Advance Television standard (ATV). DVD has an average video bit rate of 3.5 Mbits/sec or 4.69Mbits/sec for image and sound. Unlike digital television transmission, which will use fixed length packets for audio and video, DVD will use variable length packets with a maximum throughput of more than 1OMbits/sec. The higher bit rate allows for less compression of difficult to encode material. Even with all the compression, narrow-beam red light lasers are required to significantly increase the physical data density of a platter by decreasing the size of the pits. This allows 4.7 gigabytes of data on a single sided, single layer DVD. The maximum 17 gigabyte capacity is achieved by employing two reflective layers on both sides of the disk. To read the imbedded layer of data, the laser`s focal length is altered so that the top layer pits are not picked up by the reader. It will be a couple of years before we have dual-layer, double-sided DVDS, and it will be achieved in four stages. The first format to appear will be the single sided, single layer disk (4.7 gigabytes). That will allow Hollywood to begin releasing DVD movie titles. DVD-ROM will be the next phase, allowing 4.7 gigabytes of CD-ROM-like content. The third stage will be write-once disks, and stage four will be rewritable disks. These last stages presents some issues which have yet to be resolved. For one, copyrighted materials may have some form of payment system, and there is the issue that erasable disks reflect less light than today`s DVDS. The problem here is that their data most likely will not be readable on earlier built players.

  1. Skin lumps

    MedlinePLUS

    Skin lumps are any abnormal bumps or swellings on the skin. ... Common causes of skin lumps include: Lipomas, which are fatty lumps under the skin Enlarged lymph glands , usually in the armpits, neck, and ...

  2. Your Skin

    MedlinePLUS

    ... Skiing, Snowboarding, Skating Crushes What's a Booger? Your Skin KidsHealth > For Kids > Your Skin Print A A ... are really dead skin cells. continue Bye-Bye Skin Cells These old cells are tough and strong, ...

  3. Dry skin

    MedlinePLUS

    Skin - dry; Winter itch ... Dry skin is common. It happens more often in the winter when cold air outside and heated air inside cause low humidity. Forced-air furnaces make skin even drier. The skin loses moisture and may ...

  4. Skin Biopsy

    MedlinePLUS

    ... Your Best Self Smart Snacking Losing Weight Safely Skin Biopsy KidsHealth > Teens > Body > Skin Stuff > Skin Biopsy ... Preparation The Procedure Safety Results What Is a Skin Biopsy and Who Would Need One? In a ...

  5. Just how versatile are domains?

    PubMed Central

    2008-01-01

    Background Creating new protein domain arrangements is a frequent mechanism of evolutionary innovation. While some domains always form the same combinations, others form many different arrangements. This ability, which is often referred to as versatility or promiscuity of domains, its a random evolutionary model in which a domain's promiscuity is based on its relative frequency of domains. Results We show that there is a clear relationship across genomes between the promiscuity of a given domain and its frequency. However, the strength of this relationship differs for different domains. We thus redefine domain promiscuity by defining a new index, DV I ("domain versatility index"), which eliminates the effect of domain frequency. We explore links between a domain's versatility, when unlinked from abundance, and its biological properties. Conclusion Our results indicate that domains occurring as single domain proteins and domains appearing frequently at protein termini have a higher DV I. This is consistent with previous observations that the evolution of domain re-arrangements is primarily driven by fusion of pre-existing arrangements and single domains as well as loss of domains at protein termini. Furthermore, we studied the link between domain age, defined as the first appearance of a domain in the species tree, and the DV I. Contrary to previous studies based on domain promiscuity, it seems as if the DV I is age independent. Finally, we find that contrary to previously reported findings, versatility is lower in Eukaryotes. In summary, our measure of domain versatility indicates that a random attachment process is sufficient to explain the observed distribution of domain arrangements and that several views on domain promiscuity need to be revised. PMID:18854028

  6. Bioactive Peptides in Milk and Dairy Products: A Review.

    PubMed

    Park, Young Woo; Nam, Myoung Soo

    2015-01-01

    Functionally and physiologically active peptides are produced from several food proteins during gastrointestinal digestion and fermentation of food materials with lactic acid bacteria. Once bioactive peptides (BPs) are liberated, they exhibit a wide variety of physiological functions in the human body such as gastrointestinal, cardiovascular, immune, endocrine, and nervous systems. These functionalities of the peptides in human health and physiology include antihypertensive, antimicrobial, antioxidative, antithrombotic, opioid, anti-appetizing, immunomodulatory and mineral-binding activities. Most of the bioactivities of milk proteins are latent, being absent or incomplete in the original native protein, but full activities are manifested upon proteolytic digestion to release and activate encrypted bioactive peptides from the original protein. Bioactive peptides have been identified within the amino acid sequences of native milk proteins. Due to their physiological and physico-chemical versatility, milk peptides are regarded as greatly important components for health promoting foods or pharmaceutical applications. Milk and colostrum of bovine and other dairy species are considered as the most important source of natural bioactive components. Over the past a few decades, major advances and developments have been achieved on the science, technology and commercial applications of bioactive components which are present naturally in the milk. Although the majority of published works are associated with the search of bioactive peptides in bovine milk samples, some of them are involved in the investigation of ovine or caprine milk. The advent of functional foods has been facilitated by increasing scientific knowledge about the metabolic and genomic effects of diet and specific dietary components on human health. PMID:26877644

  7. Bioactive Peptides in Milk and Dairy Products: A Review

    PubMed Central

    Park, Young Woo; Nam, Myoung Soo

    2015-01-01

    Functionally and physiologically active peptides are produced from several food proteins during gastrointestinal digestion and fermentation of food materials with lactic acid bacteria. Once bioactive peptides (BPs) are liberated, they exhibit a wide variety of physiological functions in the human body such as gastrointestinal, cardiovascular, immune, endocrine, and nervous systems. These functionalities of the peptides in human health and physiology include antihypertensive, antimicrobial, antioxidative, antithrombotic, opioid, anti-appetizing, immunomodulatory and mineral-binding activities. Most of the bioactivities of milk proteins are latent, being absent or incomplete in the original native protein, but full activities are manifested upon proteolytic digestion to release and activate encrypted bioactive peptides from the original protein. Bioactive peptides have been identified within the amino acid sequences of native milk proteins. Due to their physiological and physico-chemical versatility, milk peptides are regarded as greatly important components for health promoting foods or pharmaceutical applications. Milk and colostrum of bovine and other dairy species are considered as the most important source of natural bioactive components. Over the past a few decades, major advances and developments have been achieved on the science, technology and commercial applications of bioactive components which are present naturally in the milk. Although the majority of published works are associated with the search of bioactive peptides in bovine milk samples, some of them are involved in the investigation of ovine or caprine milk. The advent of functional foods has been facilitated by increasing scientific knowledge about the metabolic and genomic effects of diet and specific dietary components on human health. PMID:26877644

  8. Bioglass Activated Skin Tissue Engineering Constructs for Wound Healing.

    PubMed

    Yu, Hongfei; Peng, Jinliang; Xu, Yuhong; Chang, Jiang; Li, Haiyan

    2016-01-13

    Wound healing is a complicated process, and fibroblast is a major cell type that participates in the process. Recent studies have shown that bioglass (BG) can stimulate fibroblasts to secrete a multitude of growth factors that are critical for wound healing. Therefore, we hypothesize that BG can stimulate fibroblasts to have a higher bioactivity by secreting more bioactive growth factors and proteins as compared to untreated fibroblasts, and we aim to construct a bioactive skin tissue engineering graft for wound healing by using BG activated fibroblast sheet. Thus, the effects of BG on fibroblast behaviors were studied, and the bioactive skin tissue engineering grafts containing BG activated fibroblasts were applied to repair the full skin lesions on nude mouse. Results showed that BG stimulated fibroblasts to express some critical growth factors and important proteins including vascular endothelial growth factor, basic fibroblast growth factor, epidermal growth factor, collagen I, and fibronectin. In vivo results revealed that fibroblasts in the bioactive skin tissue engineering grafts migrated into wound bed, and the migration ability of fibroblasts was stimulated by BG. In addition, the bioactive BG activated fibroblast skin tissue engineering grafts could largely increase the blood vessel formation, enhance the production of collagen I, and stimulate the differentiation of fibroblasts into myofibroblasts in the wound site, which would finally accelerate wound healing. This study demonstrates that the BG activated skin tissue engineering grafts contain more critical growth factors and extracellular matrix proteins that are beneficial for wound healing as compared to untreated fibroblast cell sheets. PMID:26684719

  9. Skin Conditions

    MedlinePLUS

    Your skin is your body's largest organ. It covers and protects your body. Your skin Holds body fluids in, preventing dehydration Keeps harmful ... it Anything that irritates, clogs, or inflames your skin can cause symptoms such as redness, swelling, burning, ...

  10. Skin Cancer

    MedlinePLUS

    ... are specialized skin cells that produce pigment called melanin. The melanin pigment produced by melanocytes gives skin its color. ... absorbing and scattering the energy. People with more melanin have darker skin and better protection from UV ...

  11. Electrostatic Control of Bioactivity

    SciTech Connect

    Goldberger, Joshua E.; Berns, Eric J.; Bitton, Ronit; Newcomb, Christina J.; Stupp, Samuel I.

    2012-03-15

    The power of independence: When exhibited on the surface of self-assembling peptide-amphiphile nanofibers, the hydrophobic laminin-derived IKVAV epitope induced nanofiber bundling through interdigitation with neighboring fibers and thus decreased the bioactivity of the resulting materials. The inclusion of charged amino acids in the peptide amphiphiles disrupted the tendency to bundle and led to significantly enhanced neurite outgrowth.

  12. New bioactive fatty acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many oxygenated fatty acids are bioactive compounds. Nocardia cholesterolicum and Flavobacterium DS5 convert oleic acid to 10 hydroxy stearic acid and linoleic acid to 10-hydroxy-12(Z)-octadecanoic acid. Pseudomonas aeruginosa PR3 converts oleic acid to the new compounds, 7,10-dihydroxy-8(E)-octad...

  13. New Bioactive Fatty Acids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many oxygenated fatty acids are bioactive compounds. Nocardia cholesterolicum and Flavobacterium DS5 convert oleic acid to 10 hydroxy stearic acid and linoleic acid to 10-hydroxy-12(Z)-octadecanoic acid. Pseudomonas aeruginosa PR3 converts oleic acid to new compounds, 7,10-dihydroxy-8(E)-octadecen...

  14. New bioactive lipids

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Many oxygenated fatty acids are bioactive compounds. Nocardia cholesterolicum and Flavobacterium DS5 convert oleic acid to 10 hydroxy stearic acid and linoleic acid to 10-hydroxy-12(Z)-octadecanoic acid. Pseudomonas aeruginosa PR3 converts oleic acid to the new compounds, 7,10-dihydroxy-8(E)-octad...

  15. Bioactive glass coupling with natural polyphenols: Surface modification, bioactivity and anti-oxidant ability

    NASA Astrophysics Data System (ADS)

    Cazzola, Martina; Corazzari, Ingrid; Prenesti, Enrico; Bertone, Elisa; Vernè, Enrica; Ferraris, Sara

    2016-03-01

    Polyphenols are actually achieving an increasing interest due to their potential health benefits, such as antioxidant, anticancer, antibacterial and bone stimulation abilities. However their poor bioavailability and stability hamper an effective clinical application as therapeutic principles. The opportunity to couple these biomolecules with synthetic biomaterials, in order to obtain local delivery at the site of interest, improve their bioavailability and stability and combine their properties with the ones of the substrate, is a challenging opportunity for the biomedical research. A silica based bioactive glass, CEL2, has been successfully coupled with gallic acid and natural polyphenols extracted from red grape skins and green tea leaves. The effectiveness of grafting has been verified by means of XPS analyses and the Folin&Ciocalteu tests. In vitro bioactivity has been investigated by soaking in simulated body fluid (SBF). Surface modification after functionalization and early stage reactivity in SBF have been studied by means of zeta potential electrokinetic measurements in KCl and SBF. Finally the antioxidant properties of bare and modified bioactive glasses has been investigated by means of the evaluation of free radical scavenging activity by Electron Paramagnetic Resonance (EPR)/spin trapping technique after UV photolysis of H2O2 highlighting scavenging activity of the bioactive glass.

  16. Versatile pulsed rf heterodyne spectrometer

    NASA Astrophysics Data System (ADS)

    Gibson, A. A. V.; Owers-Bradley, J. R.; Calder, I. D.; Ketterson, J. B.; Halperin, W. P.

    1981-10-01

    We present the design of a versatile rf heterodyne spectrometer covering a 100 kHz to 190 MHz frequency range, which has been useful in nuclear magnetic resonance and acoustic experiments over its whole range. Commercial instruments were used wherever possible: two units, an rf pulse generator, and a 30-MHz IF amplifier/detector were constructed and are described in detail. Also, we briefly outline application to ultrasound and NMR measurements and interfacing to a minicomputer-based data processing system.

  17. Ionic skin.

    PubMed

    Sun, Jeong-Yun; Keplinger, Christoph; Whitesides, George M; Suo, Zhigang

    2014-12-01

    Electronic skins (i.e., stretchable sheets of distributed sensors) report signals using electrons, whereas natural skins report signals using ions. Here, ionic conductors are used to create a new type of sensory sheet, called "ionic skin". Ionic skins are highly stretchable, transparent, and biocompatible. They readily measure strains from 1% to 500%, and pressures as low as 1 kPa. PMID:25355528

  18. Skin Graft

    PubMed Central

    Shimizu, Ruka; Kishi, Kazuo

    2012-01-01

    Skin graft is one of the most indispensable techniques in plastic surgery and dermatology. Skin grafts are used in a variety of clinical situations, such as traumatic wounds, defects after oncologic resection, burn reconstruction, scar contracture release, congenital skin deficiencies, hair restoration, vitiligo, and nipple-areola reconstruction. Skin grafts are generally avoided in the management of more complex wounds. Conditions with deep spaces and exposed bones normally require the use of skin flaps or muscle flaps. In the present review, we describe how to perform skin grafting successfully, and some variation of skin grafting. PMID:22570780

  19. Photocleavable linker for the patterning of bioactive molecules

    PubMed Central

    Wegner, Seraphine V.; Sentürk, Oya I.; Spatz, Joachim P.

    2015-01-01

    Herein, we report the use of a versatile photocleavable nitrobenzyl linker to micropattern a wide variety of bioactive molecules and photorelease them on demand. On one end, the linker has an NHS group that can be coupled with any amine, such as peptides, proteins or amine-linkers, and on the other end an alkyne for convenient attachment to materials with an azide functional group. This linker was conjugated with NTA-amine or the cell adhesion peptide cRGD to enable straightforward patterning of His6-tagged proteins or cells, respectively, on PEGylated glass surfaces. This approach provides a practical way to control the presentation of a wide variety of bioactive molecules with high spatial and temporal resolution. The extent of photocleavage can also be controlled to tune the biomolecule density and degree of cell attachment to the surface. PMID:26670693

  20. Bioactive glass in tissue engineering

    PubMed Central

    Rahaman, Mohamed N.; Day, Delbert E.; Bal, B. Sonny; Fu, Qiang; Jung, Steven B.; Bonewald, Lynda F.; Tomsia, Antoni P.

    2011-01-01

    This review focuses on recent advances in the development and use of bioactive glass for tissue engineering applications. Despite its inherent brittleness, bioactive glass has several appealing characteristics as a scaffold material for bone tissue engineering. New bioactive glasses based on borate and borosilicate compositions have shown the ability to enhance new bone formation when compared to silicate bioactive glass. Borate-based bioactive glasses also have controllable degradation rates, so the degradation of the bioactive glass implant can be more closely matched to the rate of new bone formation. Bioactive glasses can be doped with trace quantities of elements such as Cu, Zn and Sr, which are known to be beneficial for healthy bone growth. In addition to the new bioactive glasses, recent advances in biomaterials processing have resulted in the creation of scaffold architectures with a range of mechanical properties suitable for the substitution of loaded as well as non-loaded bone. While bioactive glass has been extensively investigated for bone repair, there has been relatively little research on the application of bioactive glass to the repair of soft tissues. However, recent work has shown the ability of bioactive glass to promote angiogenesis, which is critical to numerous applications in tissue regeneration, such as neovascularization for bone regeneration and the healing of soft tissue wounds. Bioactive glass has also been shown to enhance neocartilage formation during in vitro culture of chondrocyte-seeded hydrogels, and to serve as a subchondral substrate for tissue-engineered osteochondral constructs. Methods used to manipulate the structure and performance of bioactive glass in these tissue engineering applications are analyzed. PMID:21421084

  1. Bioactive glass in tissue engineering.

    PubMed

    Rahaman, Mohamed N; Day, Delbert E; Bal, B Sonny; Fu, Qiang; Jung, Steven B; Bonewald, Lynda F; Tomsia, Antoni P

    2011-06-01

    This review focuses on recent advances in the development and use of bioactive glass for tissue engineering applications. Despite its inherent brittleness, bioactive glass has several appealing characteristics as a scaffold material for bone tissue engineering. New bioactive glasses based on borate and borosilicate compositions have shown the ability to enhance new bone formation when compared to silicate bioactive glass. Borate-based bioactive glasses also have controllable degradation rates, so the degradation of the bioactive glass implant can be more closely matched to the rate of new bone formation. Bioactive glasses can be doped with trace quantities of elements such as Cu, Zn and Sr, which are known to be beneficial for healthy bone growth. In addition to the new bioactive glasses, recent advances in biomaterials processing have resulted in the creation of scaffold architectures with a range of mechanical properties suitable for the substitution of loaded as well as non-loaded bone. While bioactive glass has been extensively investigated for bone repair, there has been relatively little research on the application of bioactive glass to the repair of soft tissues. However, recent work has shown the ability of bioactive glass to promote angiogenesis, which is critical to numerous applications in tissue regeneration, such as neovascularization for bone regeneration and the healing of soft tissue wounds. Bioactive glass has also been shown to enhance neocartilage formation during in vitro culture of chondrocyte-seeded hydrogels, and to serve as a subchondral substrate for tissue-engineered osteochondral constructs. Methods used to manipulate the structure and performance of bioactive glass in these tissue engineering applications are analyzed. PMID:21421084

  2. MicroRNAs in skin tissue engineering.

    PubMed

    Miller, Kyle J; Brown, David A; Ibrahim, Mohamed M; Ramchal, Talisha D; Levinson, Howard

    2015-07-01

    35.2 million annual cases in the U.S. require clinical intervention for major skin loss. To meet this demand, the field of skin tissue engineering has grown rapidly over the past 40 years. Traditionally, skin tissue engineering relies on the "cell-scaffold-signal" approach, whereby isolated cells are formulated into a three-dimensional substrate matrix, or scaffold, and exposed to the proper molecular, physical, and/or electrical signals to encourage growth and differentiation. However, clinically available bioengineered skin equivalents (BSEs) suffer from a number of drawbacks, including time required to generate autologous BSEs, poor allogeneic BSE survival, and physical limitations such as mass transfer issues. Additionally, different types of skin wounds require different BSE designs. MicroRNA has recently emerged as a new and exciting field of RNA interference that can overcome the barriers of BSE design. MicroRNA can regulate cellular behavior, change the bioactive milieu of the skin, and be delivered to skin tissue in a number of ways. While it is still in its infancy, the use of microRNAs in skin tissue engineering offers the opportunity to both enhance and expand a field for which there is still a vast unmet clinical need. Here we give a review of skin tissue engineering, focusing on the important cellular processes, bioactive mediators, and scaffolds. We further discuss potential microRNA targets for each individual component, and we conclude with possible future applications. PMID:25953499

  3. Versatile document image content extraction

    NASA Astrophysics Data System (ADS)

    Baird, Henry S.; Moll, Michael A.; Nonnemaker, Jean; Casey, Matthew R.; Delorenzo, Don L.

    2006-01-01

    We offer a preliminary report on a research program to investigate versatile algorithms for document image content extraction, that is locating regions containing handwriting, machine-print text, graphics, line-art, logos, photographs, noise, etc. To solve this problem in its full generality requires coping with a vast diversity of document and image types. Automatically trainable methods are highly desirable, as well as extremely high speed in order to process large collections. Significant obstacles include the expense of preparing correctly labeled ("ground-truthed") samples, unresolved methodological questions in specifying the domain (e.g. what is a representative collection of document images?), and a lack of consensus among researchers on how to evaluate content-extraction performance. Our research strategy emphasizes versatility first: that is, we concentrate at the outset on designing methods that promise to work across the broadest possible range of cases. This strategy has several important implications: the classifiers must be trainable in reasonable time on vast data sets; and expensive ground-truthed data sets must be complemented by amplification using generative models. These and other design and architectural issues are discussed. We propose a trainable classification methodology that marries k-d trees and hash-driven table lookup and describe preliminary experiments.

  4. Skin Cancer

    MedlinePLUS

    ... Signs, symptoms Who gets, causes Diagnosis, treatment Tips Squamous cell carcinoma Stasis dermatitis Tattoo removal Tinea versicolor U - W ... of this very serious skin cancer. Learn more. Squamous cell carcinoma (SCC) This skin cancer tends to form on ...

  5. Skin Infections

    MedlinePLUS

    ... Abscess Cellulitis Taking Care of Your Skin Abscess Impetigo Ringworm Cellulitis Should I Pop My Pimple? Tips for Taking Care of Your Skin Impetigo Paronychia Pityriasis Rosea Abscess Contact Us Print Resources ...

  6. Evolving practice of the Helsinki Skin Bank.

    PubMed

    Lindford, Andrew J; Frey, Ira; Vuola, Jyrki; Koljonen, Virve

    2010-08-01

    The purpose of this study is to review the management and running of the Helsinki Skin Bank between the years 2001 and 2008. Further aims were to assess the microbiological safety of the glycerol-preserved allograft skin and analyse its clinical use. The files of the Helsinki Skin Bank were reviewed for allograft skin harvested from organ donors between 2001 and 2008. Data on harvested skin area and microbiological culture results were collected. The patients receiving allograft were also identified and operation indications analysed. Allograft skin was collected from 115 donors, with a mean of 44,335 cm(2) per year. No skin batches were discarded. Microbiological cultures of the allograft skin batches were negative in 86 (75%) cases. Thirty-five donor skin batches were used in 69 operations. The most common indication was 'Biological dressing on partial-thickness burns', comprising 52% of cases. The cost per cm(2) was 0.81euro. The use of allograft skin in the Helsinki Skin Bank is microbiologically safe and continues to provide a versatile and useful treatment modality in many major burn cases with few observed complications. As compared with synthetically produced temporary dressings currently available, our allograft skin is also more economical. PMID:20492012

  7. Skin Aging

    MedlinePLUS

    Your skin changes as you age. You might notice wrinkles, age spots and dryness. Your skin also becomes thinner and loses fat, making it ... heal, too. Sunlight is a major cause of skin aging. You can protect yourself by staying out ...

  8. Your Skin

    MedlinePLUS

    ... your body. Without skin, people's muscles, bones, and organs would be hanging out all over the place. Skin holds everything together. It also: protects our bodies helps keep our bodies at just the right temperature allows us to have the sense of touch What's your biggest skin worry? Don' ...

  9. Bioactivity in Organic Chemistry Courses.

    ERIC Educational Resources Information Center

    Ferguson, Lloyd N.

    1980-01-01

    Presented are three ways in which bioactivity of organic compounds has been introduced in organic chemistry courses. One is to point out a typical bioactivity of a given functional group. A second is to discuss biorganic mechanisms. A third is to draw structure-activity correlations (SAR). (Author/HM)

  10. Folate in Skin Cancer Prevention

    PubMed Central

    Williams, J.D.; Jacobson, Elaine L.; Kim, H.; Kim, M.; Jacobson, M.K.

    2013-01-01

    Skin, the largest, most exposed organ of the body, provides a protective interface between humans and the environment. One of its primary roles is protection against exposure to sunlight, a major source of skin damage where the UV radiation (UVR) component functions as a complete carcinogen. Melanin pigmentation and the evolution of dark skin is an adaptive protective mechanism against high levels of UVR exposure. Recently, the hypothesis that skin pigmentation balances folate preservation and Vitamin D production has emerged. Both micronutrients are essential for reproductive success. Photodegradation of bioactive folates suggests a mechanism for the increased tendency of populations of low melanin pigmentation residing in areas of high UV exposure to develop skin cancers. Folate is proposed as a cancer prevention target for its role in providing precursors for DNA repair and replication, as well as its ability to promote genomic integrity through the generation of methyl groups needed for control of gene expression. The cancer prevention potential of folate has been demonstrated by large-scale epidemiological and nutritional studies indicating that decreased folate status increases the risk of developing certain cancers. While folate deficiency has been extensively documented by analysis of human plasma, folate status within skin has not been widely investigated. Nevertheless, inefficient delivery of micronutrients to skin and photolysis of folate argue that documented folate deficiencies will be present if not exacerbated in skin. Our studies indicate a critical role for folate in skin and the potential to protect sun exposed skin by effective topical delivery as a strategy for cancer prevention. PMID:22116700

  11. Sensitive skin.

    PubMed

    Misery, L; Loser, K; Ständer, S

    2016-02-01

    Sensitive skin is a clinical condition defined by the self-reported facial presence of different sensory perceptions, including tightness, stinging, burning, tingling, pain and pruritus. Sensitive skin may occur in individuals with normal skin, with skin barrier disturbance, or as a part of the symptoms associated with facial dermatoses such as rosacea, atopic dermatitis and psoriasis. Although experimental studies are still pending, the symptoms of sensitive skin suggest the involvement of cutaneous nerve fibres and neuronal, as well as epidermal, thermochannels. Many individuals with sensitive skin report worsening symptoms due to environmental factors. It is thought that this might be attributed to the thermochannel TRPV1, as it typically responds to exogenous, endogenous, physical and chemical stimuli. Barrier disruptions and immune mechanisms may also be involved. This review summarizes current knowledge on the epidemiology, potential mechanisms, clinics and therapy of sensitive skin. PMID:26805416

  12. Bioactivity of certain Egyptian Ficus species.

    PubMed

    Mousa, O; Vuorela, P; Kiviranta, J; Wahab, S A; Hiltunen, R; Vuorela, H

    1994-01-01

    The fruit extracts of Ficus sycomorus L., F. benjamina L., F. bengalensis L. and F. religiosa L. were screened for bioactivity. F. bengalensis and F. religiosa demonstrated activity in the brine shrimp test (Artemia salina) which indicates toxicity, whereas F. sycomorus and F. benjamina showed no activity. All the fruit extracts exhibited antitumor activity in the potato disc bioassay. None of the tested extracts showed any marked inhibition on the uptake of calcium into rat pituitary cells GH4C1. The extracts of the four tested Ficus species had significant antibacterial activity, but no antifungal activity. The results of this preliminary investigation support the traditional use of these plants in folk medicine for respiratory disorders and certain skin diseases. PMID:8170162

  13. Antimicrobial Peptides: Versatile Biological Properties

    PubMed Central

    Pushpanathan, Muthuirulan; Rajendhran, Jeyaprakash

    2013-01-01

    Antimicrobial peptides are diverse group of biologically active molecules with multidimensional properties. In recent past, a wide variety of AMPs with diverse structures have been reported from different sources such as plants, animals, mammals, and microorganisms. The presence of unusual amino acids and structural motifs in AMPs confers unique structural properties to the peptide that attribute for their specific mode of action. The ability of these active AMPs to act as multifunctional effector molecules such as signalling molecule, immune modulators, mitogen, antitumor, and contraceptive agent makes it an interesting candidate to study every aspect of their structural and biological properties for prophylactic and therapeutic applications. In addition, easy cloning and recombinant expression of AMPs in heterologous plant host systems provided a pipeline for production of disease resistant transgenic plants. Besides these properties, AMPs were also used as drug delivery vectors to deliver cell impermeable drugs to cell interior. The present review focuses on the diversity and broad spectrum antimicrobial activity of AMPs along with its multidimensional properties that could be exploited for the application of these bioactive peptides as a potential and promising drug candidate in pharmaceutical industries. PMID:23935642

  14. VEGAS: VErsatile GBT Astronomical Spectrometer

    NASA Astrophysics Data System (ADS)

    Bussa, Srikanth; VEGAS Development Team

    2012-01-01

    The National Science Foundation Advanced Technologies and Instrumentation (NSF-ATI) program is funding a new spectrometer backend for the Green Bank Telescope (GBT). This spectrometer is being built by the CICADA collaboration - collaboration between the National Radio Astronomy Observatory (NRAO) and the Center for Astronomy Signal Processing and Electronics Research (CASPER) at the University of California Berkeley.The backend is named as VErsatile GBT Astronomical Spectrometer (VEGAS) and will replace the capabilities of the existing spectrometers. This backend supports data processing from focal plane array systems. The spectrometer will be capable of processing up to 1.25 GHz bandwidth from 8 dual polarized beams or a bandwidth up to 10 GHz from a dual polarized beam.The spectrometer will be using 8-bit analog to digital converters (ADC), which gives a better dynamic range than existing GBT spectrometers. There will be 8 tunable digital sub-bands within the 1.25 GHz bandwidth, which will enhance the capability of simultaneous observation of multiple spectral transitions. The maximum spectral dump rate to disk will be about 0.5 msec. The vastly enhanced backend capabilities will support several science projects with the GBT. The projects include mapping temperature and density structure of molecular clouds; searches for organic molecules in the interstellar medium; determination of the fundamental constants of our evolving Universe; red-shifted spectral features from galaxies across cosmic time and survey for pulsars in the extreme gravitational environment of the Galactic Center.

  15. Bioactive composites with designed interfaces

    NASA Astrophysics Data System (ADS)

    Orefice, Rodrigo Lambert

    Bioactive glasses can bond to bone and even soft tissue. However, they are usually weak, brittle and hard to process in specific shapes. The goal of this work is to produce polymer composites having bioactive materials as a reinforcing phase that would display both bioactive behavior and mechanical properties compatible to bone. Polysulfone and bioactive glass particulate were combined in composites with different volume fractions. Composites with 40 vol.% of particulate were submitted to in vitro tests in simulated body fluids. The recorded rates of hydroxy-carbonate-apatite layer deposition were close to the ones observed for pure bioactive glasses. Mechanical properties showed values of elastic modulus, strain at failure and strength within the range of cortical bone for composites with high volume fraction of particles. Fibers can usually favor higher levels of reinforcement in composites than particles. Novel multicomponent fibers were prepared by using the sol-gel method. They were determined to be bioactive in vitro and were successfully used as a reinforcing phase in polysulfone composites. Properties of the bioactive composites were modified by altering the chemistry and structure of the interfaces. Polymers with sulfonic acid and silane groups were specially designed to interact with both the silica surface and the polymer matrix. Nano-composites with a structure and chemistry in between the macrocomponents of the composite were prepared by combining a silanated polymer and silica sol-gel. When applied as interfacial agents, these nano-composites as well as the modified polymers improved the overall properties of the bioactive system. A decay in mechanical properties was observed for composites submitted to an in vitro test. The developed interfacial agents successfully reduced the degree of degradation in properties. Interactions occurring at the interfaces of bioactive composites were studied using Atomic Force Microscopy (AFM). The effect of the structure and chemistry of interfaces was correlated to physical and chemical processes occurring at the interfaces and to the overall properties of composites.

  16. Nocardiopsis species: a potential source of bioactive compounds.

    PubMed

    Bennur, T; Ravi Kumar, A; Zinjarde, S S; Javdekar, V

    2016-01-01

    Members of the genus Nocardiopsis are an ecologically versatile and biotechnologically important group of Actinomycetes. Most of the isolates are halotolerant or halophilic and they prevail in soils, marine environments or hypersaline locations. To aid their survival under these conditions, they mainly produce extremozymes, compatible solutes, surfactants and bioactive compounds. The current review details the bioactive compounds obtained for this genus. Important antimicrobial agents obtained from this genus include polyketides, phenzines, quinoline alkaloids, terphenyls, proteins, thiopeptides and amines. Polyketides and peptides displaying potent anticancer activities are also significant. Tumour promoting agents, P-glycoprotein (P-gp) inhibitors, immunomodulators and protein kinase inhibitors are other relevant products obtained from Nocardiopsis species. Structurally, polyketides (synthesized by polyketide synthases) and peptides (made by nonribosomal peptide synthetases or cyclodipeptide synthases) are important compounds. Considered here are also toxins, anti photoaging and adipogenic agents produced by this genus. The gene clusters mediating the synthesis of bioactive compounds have been described. Commercially available products (Apoptolidins and K-252a) derived from this genus have also been described. This review highlights the significance of a single genus in producing an assortment of compounds with varied biological activities. On account of these features, the members of this genus have established a place for themselves and are of considerable value in producing compounds with profound bio-medical applications. PMID:26369300

  17. Double scalping flap: a versatile technique in scalp reconstruction.

    PubMed

    Papadopoulos, Othon; Karypidis, Dimitrios; Moustaki, Margarita; Chrisostomidis, Chrisostomos; Grigorios, Champsas; Epaminondas, Kostopoulos; Frangoulis, Marios

    2009-09-01

    Scalp reconstruction is a challenging area in plastic surgery. The susceptibility of potentially exposed brain tissue is almost always a concern along with the provision of adequate soft tissue coverage in cases of full-thickness defects. The applied reconstructive strategy also affects efficiency in malignant disease treatment providing both local control of the disease and vigorous monitoring for recurrence or metastasis. The general condition of the patients presenting with malignant lesions of the scalp is often impaired because of old age or concomitant disease. Therefore, demanding, long-lasting, or multistage procedures may often be undesirable. The double scalping flap comprises a 1-stage procedure, which can be used in most full-thickness defects of the vertex of the scalp. Some of the primary advantages of the double scalping flap procedure are its versatility and arc of rotation, its minimal donor site morbidity, being relatively simple, and being a short technique. Disadvantages that may be considered are the loss of hair-bearing skin at the occipital region and the poor color and texture match between scalp skin and the split-thickness skin graft that is used on the donor site. We present 2 patients with exemplary case of neglected malignancy of the scalp and their successful treatment using the double scalping flap. Comparison and contrast of alternative reconstructive procedures are also included to further investigate scalp reconstruction. PMID:19816283

  18. Skin optics

    SciTech Connect

    van Gemert, M.J.; Jacques, S.L.; Sterenborg, H.J.; Star, W.M.

    1989-12-01

    Quantitative dosimetry in the treatment of skin disorders with (laser) light requires information on propagation of light in the skin related to the optical properties of the individual skin layers. This involves the solution of the integro-differential equation of radiative transfer in a model representing skin geometry, as well as experimental methods to determine the optical properties of each skin layer. These activities are unified under the name skin optics. This paper first reviews the current status of tissue optics, distinguishing between the cases of: dominant absorption, dominant scattering, and scattering about equal to absorption. Then, previously published data as well as some current unpublished data on (human) stratum corneum, epidermis and dermis, have been collected and/or (re)analyzed in terms of absorption coefficient, scattering coefficient, and anisotropy factor of scattering. The results are that the individual skin layers show strongly forward scattering (anisotropy factors between 0.7 and 0.9). The absorption and scattering data show that for all wavelengths considered scattering is much more important than absorption. Under such circumstances, solutions to the transport equation for a multilayer skin model and finite beam laser irradiation are currently not yet available. Hence, any quantitative dosimetry for skin treated with (laser) light is currently lacking.

  19. Bioactivity of metallic biomaterials with anatase layers deposited in acidic titanium tetrafluoride solution.

    PubMed

    Wu, Jin-Ming; Xiao, Fan; Hayakawa, Satoshi; Tsuru, Kanji; Takemoto, Shinji; Osaka, Akiyoshi

    2003-12-01

    A simple and versatile treatment was developed to provide various metallic biomaterials such as Ti, NiTi, Ta and SUS 316L stainless steel with in vitro bioactivity or ability to deposit carbonate-incorporated apatite in a simulated body fluid (Kokubo solution). A well-crystallized anatase layer deposited on the metallic biomaterials surfaces after soaking them at 60 degrees C for 24 h in an aqueous solution of titanium tetrafluoride (40 mM) whose pH was adjusted to 1.9 with HCl. The as-coated anatase layers did not deposit apatite. When heated at 300 degrees C they were so bioactive as to deposit apatite within 5 day(s) in the Kokubo solution. The trace amount of fluorine weakly bound in the as-coated anatase layers was suggested to be one of the factors that suppressed the bioactivity. PMID:15348494

  20. Versatile machine mills, saws light materials

    NASA Technical Reports Server (NTRS)

    Rauschl, J. A.

    1966-01-01

    Versatile milling/sawing machine performs angle cuts, flat and profile milling, machining of grooves and slots, and edge trimming of phenolic panels. The machine is mounted on rails above a table equipped with vacuum capability for holding workpieces.

  1. Applications for the versatile molybdate inhibitor

    SciTech Connect

    Vukasovich, M.S

    1990-05-01

    Molybdate compounds are widely used as corrosion inhibitors to protect both ferrous and nonferrous metals in diverse corrosive environments. This review gives testimony to its versatility by citing many of its practical applications.

  2. Methanol: A Versatile Fuel for Immediate Use

    ERIC Educational Resources Information Center

    Reed, T. B.; Lerner, R. M.

    1973-01-01

    Advocates the large-scale production and use of methanol as a substitute for the diminishing reserves of low-cost petroleum resources. Describes the manufacturing process and advantages of the versatile fuel. (JR)

  3. Bioactive Glasses: Frontiers and Challenges

    PubMed Central

    Hench, Larry L.; Jones, Julian R.

    2015-01-01

    Bioactive glasses were discovered in 1969 and provided for the first time an alternative to nearly inert implant materials. Bioglass formed a rapid, strong, and stable bond with host tissues. This article examines the frontiers of research crossed to achieve clinical use of bioactive glasses and glass–ceramics. In the 1980s, it was discovered that bioactive glasses could be used in particulate form to stimulate osteogenesis, which thereby led to the concept of regeneration of tissues. Later, it was discovered that the dissolution ions from the glasses behaved like growth factors, providing signals to the cells. This article summarizes the frontiers of knowledge crossed during four eras of development of bioactive glasses that have led from concept of bioactivity to widespread clinical and commercial use, with emphasis on the first composition, 45S5 Bioglass®. The four eras are (a) discovery, (b) clinical application, (c) tissue regeneration, and (d) innovation. Questions still to be answered for the fourth era are included to stimulate innovation in the field and exploration of new frontiers that can be the basis for a general theory of bioactive stimulation of regeneration of tissues and application to numerous clinical needs. PMID:26649290

  4. Bioactive Glasses: Frontiers and Challenges.

    PubMed

    Hench, Larry L; Jones, Julian R

    2015-01-01

    Bioactive glasses were discovered in 1969 and provided for the first time an alternative to nearly inert implant materials. Bioglass formed a rapid, strong, and stable bond with host tissues. This article examines the frontiers of research crossed to achieve clinical use of bioactive glasses and glass-ceramics. In the 1980s, it was discovered that bioactive glasses could be used in particulate form to stimulate osteogenesis, which thereby led to the concept of regeneration of tissues. Later, it was discovered that the dissolution ions from the glasses behaved like growth factors, providing signals to the cells. This article summarizes the frontiers of knowledge crossed during four eras of development of bioactive glasses that have led from concept of bioactivity to widespread clinical and commercial use, with emphasis on the first composition, 45S5 Bioglass(®). The four eras are (a) discovery, (b) clinical application, (c) tissue regeneration, and (d) innovation. Questions still to be answered for the fourth era are included to stimulate innovation in the field and exploration of new frontiers that can be the basis for a general theory of bioactive stimulation of regeneration of tissues and application to numerous clinical needs. PMID:26649290

  5. Skin graft

    MedlinePLUS

    ... layers of skin from the donor site (the epidermis) and the layer under the epidermis (the dermis). The donor site can be any ... Orgill DP. Skin graft. In: Neligan PC, ed. Plastic Surgery . 3rd ed. Philadelphia, PA: Elsevier; 2013:chap ...

  6. Gamma Radiation Effects on Peanut Skin Antioxidants

    PubMed Central

    de Camargo, Adriano Costa; de Souza Vieira, Thais Maria Ferreira; Regitano-DArce, Marisa Aparecida Bismara; Calori-Domingues, Maria Antonia; Canniatti-Brazaca, Solange Guidolin

    2012-01-01

    Peanut skin, which is removed in the peanut blanching process, is rich in bioactive compounds with antioxidant properties. The aims of this study were to measure bioactive compounds in peanut skins and evaluate the effect of gamma radiation on their antioxidant activity. Peanut skin samples were treated with 0.0, 5.0, 7.5, or 10.0 kGy gamma rays. Total phenolics, condensed tannins, total flavonoids, and antioxidant activity were evaluated. Extracts obtained from the peanut skins were added to refined-bleached-deodorized (RBD) soybean oil. The oxidative stability of the oil samples was determined using the Oil Stability Index method and compared to a control and synthetic antioxidants (100 mg/kg BHT and 200 mg/kg TBHQ). Gamma radiation changed total phenolic content, total condensed tannins, total flavonoid content, and the antioxidant activity. All extracts, gamma irradiated or not, presented increasing induction period (h), measured by the Oil Stability Index method, when compared with the control. Antioxidant activity of the peanut skins was higher than BHT. The present study confirmed that gamma radiation did not affect the peanut skin extracts antioxidative properties when added to soybean oil. PMID:22489142

  7. Gamma radiation effects on peanut skin antioxidants.

    PubMed

    de Camargo, Adriano Costa; de Souza Vieira, Thais Maria Ferreira; Regitano-D'Arce, Marisa Aparecida Bismara; Calori-Domingues, Maria Antonia; Canniatti-Brazaca, Solange Guidolin

    2012-01-01

    Peanut skin, which is removed in the peanut blanching process, is rich in bioactive compounds with antioxidant properties. The aims of this study were to measure bioactive compounds in peanut skins and evaluate the effect of gamma radiation on their antioxidant activity. Peanut skin samples were treated with 0.0, 5.0, 7.5, or 10.0 kGy gamma rays. Total phenolics, condensed tannins, total flavonoids, and antioxidant activity were evaluated. Extracts obtained from the peanut skins were added to refined-bleached-deodorized (RBD) soybean oil. The oxidative stability of the oil samples was determined using the Oil Stability Index method and compared to a control and synthetic antioxidants (100 mg/kg BHT and 200 mg/kg TBHQ). Gamma radiation changed total phenolic content, total condensed tannins, total flavonoid content, and the antioxidant activity. All extracts, gamma irradiated or not, presented increasing induction period (h), measured by the Oil Stability Index method, when compared with the control. Antioxidant activity of the peanut skins was higher than BHT. The present study confirmed that gamma radiation did not affect the peanut skin extracts' antioxidative properties when added to soybean oil. PMID:22489142

  8. Skin Substitutes

    PubMed Central

    Howe, Nicole; Cohen, George

    2014-01-01

    In a relatively short timespan, a wealth of new skin substitutes made of synthetic and biologically derived materials have arisen for the purpose of wound healing of various etiologies. This review article focuses on providing an overview of skin substitutes including their indications, contraindications, benefits, and limitations. The result of this overview was an appreciation of the vast array of options available for clinicians, many of which did not exist a short time ago. Yet, despite the rapid expansion this field has undergone, no ideal skin substitute is currently available. More research in the field of skin substitutes and wound healing is required not only for the development of new products made of increasingly complex biomolecular material, but also to compare the existing skin substitutes. PMID:25371771

  9. Analyzing cranberry bioactive compounds.

    PubMed

    Côté, J; Caillet, S; Doyon, G; Sylvain, J-F; Lacroix, M

    2010-10-01

    There is a growing public interest for the North American cranberry (Vaccinium macrocarpon) as a functional food because of the potential health benefits linked to phytochemical compounds present in the fruit--the anthocyanin pigments, responsible for its brilliant red color, and other secondary plant metabolites (flavonols, flavan-3-ols, proanthocyanidins, and phenolic acid derivatives). Isolation of these phenolic compounds and flavonoids from a sample matrix is a prerequisite to any comprehensive analysis scheme. By far the most widely employed analytical technique for the characterization of these compounds has been high-performance liquid chromatography(HPLC) coupled with ultraviolet-visible(UV/Vis) and mass spectrometer(MS) detection. This review covers the cranberry major bioactive compounds, the extraction and purification methods, and the analytical conditions for HPLC used to characterize them. Extraction, chromatographic separation and detection strategies, analyte determinations, and applications in HPLC are discussed and the information regarding methods of specific cranberry analyte analyses has been summarized in tabular form to provide a means of rapid access to information pertinent to the reader. PMID:20924868

  10. Major Australian tropical fruits biodiversity: bioactive compounds and their bioactivities.

    PubMed

    Pierson, Jean T; Dietzgen, Ralf G; Shaw, Paul N; Roberts-Thomson, Sarah J; Monteith, Gregory R; Gidley, Michael J

    2012-03-01

    The plant kingdom harbours many diverse bioactive molecules of pharmacological relevance. Temperate fruits and vegetables have been highly studied in this regard, but there have been fewer studies of fruits and vegetables from the tropics. As global consumers demand and are prepared to pay for new appealing and exotic foods, tropical fruits are now being more intensively investigated. Polyphenols and major classes of compounds like flavonoids or carotenoids are ubiquitously present in these fruits, as they are in the temperate ones, but particular classes of compounds are unique to tropical fruits and other plant parts. Bioactivity studies of compounds specific to tropical fruit plants may lead to new drug discoveries, while the synergistic action of the wide range of diverse compounds contained in plant extracts underlies nutritional and health properties of tropical fruits and vegetables. The evidence for in vitro and animal bioactivities is a strong indicator of the pharmacological promise shown in tropical fruit plant biodiversity. In this review, we will discuss both the occurrence of potential bioactive compounds isolated and identified from a selection of tropical fruit plants of importance in Australia, as well as recent studies of bioactivity associated with such fruits and other fruit plant parts. PMID:22147637

  11. Nitroxide radical biostability in skin.

    PubMed

    Fuchs, J; Freisleben, H J; Podda, M; Zimmer, G; Milbradt, R; Packer, L

    1993-10-01

    Nitroxide radicals are important chemical tools in dermatologic research (e.g., for studying biophysical properties of skin lipids and epidermal membranes with the method of electron paramagnetic resonance, EPR, spectroscopy). However, nitroxides may loose their paramagnetic properties in biological tissues, which could limit their usefulness in biomedical applications. We analyzed the biostability of various chemical types of nitroxide radicals in keratinocytes, epidermis homogenate, and intact skin. EPR signal loss of imidazoline, pyrrolidine, piperidine, and oxazolidine nitroxides is attributed to their reduction to the corresponding hydroxylamine. The rate of nitroxide reduction in skin varies considerably with nitroxide ring structure and substitution. The order of nitroxide stability in isolated human keratinocytes, mouse epidermis homogenate, and intact mouse and human skin is imidazoline > pyrrolidine > di-t-butylnitroxide (DTBN) > piperidine > oxazolidine. Cationic nitroxides are reduced much faster than neutral or anionic probes, presumably due to transmembrane electron shuttle or internalization. The results indicate that imidazoline- and pyrrolidine-type nitroxides should be used when high biostability of nitroxides is needed. Piperidine-type nitroxides are versatile probes for studying one-electron transfer reactions in skin. PMID:8225023

  12. Skin Care.

    PubMed

    Clark, Amelia; Hessler, Jill L

    2015-08-01

    Aging skin is among the most common patient concerns in a facial plastic surgery practice. Ultraviolet (UV)-induced damage expedites the pace of intrinsic aging, resulting in many of the visible signs of aging, such as rough skin texture, pigmentation irregularities, fine and deep wrinkling, and inelasticity. Primary prevention of UV and environmental damage with proper skin care and the use of sunscreen are critical. There is great interest in topically applied products to reverse or delay the visible signs of photoaging. We discuss the most common topically applied agents for photoaging, reviewing their mechanisms and supporting evidence. PMID:26208767

  13. Bioactive proteins in breast milk.

    PubMed

    Lnnerdal, Bo

    2013-03-01

    Human milk contains many proteins that have been shown to be bioactive, but it is still not known whether these activities are exerted in breast-fed infants. These bioactivities include enzyme activities, enhancement of nutrient absorption, growth stimulation, modulation of the immune system and defence against pathogens. The antimicrobial activities are very diverse, ranging from stimulation of beneficial microorganisms (i.e. prebiotic effects), killing or inhibition of growth of pathogens, to mechanisms preventing attachment or invasion of harmful microorganisms. Among the bioactive proteins are lactoferrin, lysozyme, secretory immunoglobulin A, haptocorrin, lactoperoxidase, ?-lactalbumin, bile salt stimulated lipase, ?- and ?-casein, and tumour growth factor ?. Human milk proteins may be largely resistant against digestion in the gastrointestinal tract, be partially digested into bioactive peptides, or be more or less completely digested and utilised as a source of amino acids. These events can be studied using an in vitro digestion model, which is useful for predicting results in human infants. Some bovine milk proteins, for example, lactoferrin and tumour growth factor ?, may also resist proteolysis and be capable of exerting bioactivities similar to those of human milk proteins. PMID:23448314

  14. Skin Cancer

    MedlinePLUS

    ... States. The two most common types are basal cell cancer and squamous cell cancer. They usually form on the head, face, ... If not treated, some types of skin cancer cells can spread to other tissues and organs. Treatments ...

  15. Skin Cancer

    MedlinePLUS

    ... Review. 21 Wu S, Han J, Laden F, Qureshi AA. Long-term ultraviolet flux, other potential risk factors, ... MR, Shive ML, Chren MM, Han J, Qureshi AA, Linos E. Indoor tanning and non-melanoma skin ...

  16. Hyperelastic skin

    MedlinePLUS

    ... Danlos syndrome. People with this disorder have very elastic skin. They also have joints that can be ... genetic disorder that causes fragmentation and mineralization of elastic fibers in some tissues) Subcutaneous T-cell lymphoma ...

  17. Skin turgor

    MedlinePLUS

    ... decreased tearing )? Tests that may be performed: Blood chemistry (such as a chem-20 ) CBC Urinalysis Intravenous fluids may be needed for severe dehydration. You may need medicines to treat other conditions that affect skin turgor and elasticity.

  18. Cryotherapy - skin

    MedlinePLUS

    ... It usually takes less than a minute. The freezing may cause some discomfort. Your health care provider ... to pain and infection Scarring, especially if the freezing was prolonged or deeper areas of the skin ...

  19. Skin Cancer

    MedlinePLUS

    ... exposure to ultraviolet light, which is found in sunlight and in lights used in tanning salons. What ... the safe-sun guidelines. 1. Avoid the sun. Sunlight damages your skin. The sun is strongest during ...

  20. Senescent Skin

    PubMed Central

    Kushniruk, William

    1974-01-01

    The cutaneous surface is continually influenced by aging and environmental factors. A longer life span is accompanied by an increase in the frequency of problems associated with aging skin. Although most of these changes and lesions are not life threatening, the premalignant lesions must be recognized and treated. The common aging and actinic skin changes are discussed and appropriate management is described. ImagesFig. 1Fig. 2Fig. 3Fig. 4 PMID:20469067

  1. Skin care and incontinence

    MedlinePLUS

    Incontinence - skin care ... in a wheelchair, regular chair, or bed TAKING CARE OF THE SKIN Using diapers and other products ... skin. Over time, the skin breaks down. Special care must be taken to keep the skin clean ...

  2. Mushroom Lectins: Specificity, Structure and Bioactivity Relevant to Human Disease

    PubMed Central

    Hassan, Mohamed Ali Abol; Rouf, Razina; Tiralongo, Evelin; May, Tom W.; Tiralongo, Joe

    2015-01-01

    Lectins are non-immunoglobulin proteins that bind diverse sugar structures with a high degree of selectivity. Lectins play crucial role in various biological processes such as cellular signaling, scavenging of glycoproteins from the circulatory system, cell–cell interactions in the immune system, differentiation and protein targeting to cellular compartments, as well as in host defence mechanisms, inflammation, and cancer. Among all the sources of lectins, plants have been most extensively studied. However, more recently fungal lectins have attracted considerable attention due to their antitumor, antiproliferative and immunomodulatory activities. Given that only 10% of mushroom species are known and have been taxonomically classified, mushrooms represent an enormous unexplored source of potentially useful and novel lectins. In this review we provide an up-to-date summary on the biochemical, molecular and structural properties of mushroom lectins, as well as their versatile applications specifically focusing on mushroom lectin bioactivity. PMID:25856678

  3. Mushroom lectins: specificity, structure and bioactivity relevant to human disease.

    PubMed

    Hassan, Mohamed Ali Abol; Rouf, Razina; Tiralongo, Evelin; May, Tom W; Tiralongo, Joe

    2015-01-01

    Lectins are non-immunoglobulin proteins that bind diverse sugar structures with a high degree of selectivity. Lectins play crucial role in various biological processes such as cellular signaling, scavenging of glycoproteins from the circulatory system, cell-cell interactions in the immune system, differentiation and protein targeting to cellular compartments, as well as in host defence mechanisms, inflammation, and cancer. Among all the sources of lectins, plants have been most extensively studied. However, more recently fungal lectins have attracted considerable attention due to their antitumor, antiproliferative and immunomodulatory activities. Given that only 10% of mushroom species are known and have been taxonomically classified, mushrooms represent an enormous unexplored source of potentially useful and novel lectins. In this review we provide an up-to-date summary on the biochemical, molecular and structural properties of mushroom lectins, as well as their versatile applications specifically focusing on mushroom lectin bioactivity. PMID:25856678

  4. Stem cells in embryonic skin development.

    PubMed

    Forni, Maria F; Trombetta-Lima, Marina; Sogayar, Mari C

    2012-01-01

    The skin is a complex stratified organ which acts not only as a permeability barrier and defense against external agents, but also has essential thermoregulatory, sensory and metabolic functions. Due to its high versatility and activity, the skin undergoes continuous self-renewal to repair damaged tissue and replace old cells. Consequently, the skin is a reservoir for adult stem cells of different embryonic origins. Skin stem cell populations reside in the adult hair follicle, sebaceous gland, dermis and epidermis. However, the origin of most of the stem cell populations found in the adult epidermis is still unknown. Far more unknown is the embryonic origin of other stem cells that populate the other layers of this tissue. In this review we attempt to clarify the emergence, structure, markers and embryonic development of diverse populations of stem cells from the epidermis, dermis and related appendages such as the sebaceous gland and hair follicle. PMID:23283431

  5. Bare Bones of Bioactive Glass

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Paul Ducheyne, a principal investigator in the microgravity materials science program and head of the University of Pernsylvania's Center for Bioactive Materials and Tissue Engineering, is leading the trio as they use simulated microgravity to determine the optimal characteristics of tiny glass particles for growing bone tissue. The result could make possible a much broader range of synthetic bone-grafting applications. Even in normal gravity, bioactive glass particles enhance bone growth in laboratory tests with flat tissue cultures. Ducheyne and his team believe that using the bioactive microcarriers in a rotating bioreactor in microgravity will produce improved, three-dimensional tissue cultures. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: NASA and University of Pennsylvania Center for Bioactive Materials and Tissue Engineering.

  6. A Versatile Technique for Solving Quintic Equations

    ERIC Educational Resources Information Center

    Kulkarni, Raghavendra G.

    2006-01-01

    In this paper we present a versatile technique to solve several types of solvable quintic equations. In the technique described here, the given quintic is first converted to a sextic equation by adding a root, and the resulting sextic equation is decomposed into two cubic polynomials as factors in a novel fashion. The resultant cubic equations are

  7. Guinea Pigs: Versatile Animals for the Classroom

    ERIC Educational Resources Information Center

    Barman, Charles R.

    1977-01-01

    Guinea pigs are presented as versatile classroom animals. Suggestions for animal behavior and genetics studies are given. Also included is information concerning sex determination and the breeding of guinea pigs, and hints on keeping these animals in the classroom. References and illustrations complete the article. (MA)

  8. [EFFECT OF BIOACTIVE ALDEHYDES ON GELATIN PROPERTIES].

    PubMed

    Krysyuk, I P; Dzvonkevych, N D; Volodina, T T; Popova, N N; Shandrenko, S G

    2015-01-01

    Bioactive aldehydes are among main factors of proteins postsynthetic modifications, which are the cause and consequence of many diseases. Comparative study of some aldehydes modifying action on gelatin was carried out in vitro. Gelatin samples (20 mM) were incubated with: ribose, deoxyribose, glyoxal, methylglyoxal, formaldehyde, acrolein (20 mM each) and their combinations in 0.1 M Naphosphate buffer (pH 7.4) containing 0.02% sodium azide at 37 C in the dark for 30 days. We investigated the fluorescent properties of these samples and their molecular weight distribution by electrophoresis. It has been revealed that formed adducts had different fluorescence spectra. According to fluorescence intensity these aldehydes were put in order: formaldehyde < methylglyoxal < acrolein skin surface for collagen crosslinks determination has to be verified by other tests for proteins postsynthetic modifications. PMID:26255345

  9. Ex vivo percutaneous absorption of ketamine, bupivacaine, diclofenac, gabapentin, orphenadrine, and pentoxifylline: comparison of versatile cream vs. reference cream.

    PubMed

    Wang, Xuexuan; Black, Laura

    2013-01-01

    This ex vivo human percutaneous absorption study evaluated a set of six model drugs (ketamine hydrochloride, bupivacaine hydrochloride, diclofenac sodium, gabapentin, orphenadrine citrate, pentoxifylline) from two popular formulations for topically applied compounding preparations. The compounded preparations used in this study were Versatile cream and a reference cream. Each formulation was applied to human trunk skin mounted on Franz Diffusion Cells, 50 mg/chamber (or 28.2 mg/cm2). Serial dermal receiver solutions were collected for 48 hours. Analysis of the resultant data supports the concept that the Versatile base formulation provides improved characteristics relative to the reference base. This is of key importance where the patient does not show clinical improvement when a conventional topical delivery vehicle is used in the formulation. From the results, it is reasonable to anticipate that, relative to the reference formulation, the Versatile formulation provides enhanced transdermal delivery of some analgesic medications. PMID:24579304

  10. Bioactive natural products from Lysobacter

    PubMed Central

    Xie, Yunxuan; Wright, Stephen; Shen, Yuemao

    2012-01-01

    The gliding Gram-negative Lysobacter bacteria are emerging as a promising source of new bioactive natural products. These ubiquitous freshwater and soil microorganisms are fast growing, simple to use and maintain, and genetically amenable for biosynthetic engineering. This Highlight reviews a group of biologically active and structurally distinct natural products from the genus Lysobacter, with a focus on their biosyntheses. Although Lysobacter sp. are known as prolific producers of bioactive natural products, detailed molecular mechanistic studies of their enzymatic assembly have been surprisingly scarce. We hope to provide a snapshot of the important work done on the lysobacterial natural products and to provide useful information for future biosynthetic engineering of novel antibiotics in Lysobacter. PMID:22898908

  11. Bioactive natural products from Lysobacter.

    PubMed

    Xie, Yunxuan; Wright, Stephen; Shen, Yuemao; Du, Liangcheng

    2012-11-01

    The gliding Gram-negative Lysobacter bacteria are emerging as a promising source of new bioactive natural products. These ubiquitous freshwater and soil microorganisms are fast growing, simple to use and maintain, and genetically amenable for biosynthetic engineering. This Highlight reviews a group of biologically active and structurally distinct natural products from the genus Lysobacter, with a focus on their biosyntheses. Although Lysobacter sp. are known as prolific producers of bioactive natural products, detailed molecular mechanistic studies of their enzymatic assembly have been surprisingly scarce. We hope to provide a snapshot of the important work done on the lysobacterial natural products and to provide useful information for future biosynthetic engineering of novel antibiotics in Lysobacter. PMID:22898908

  12. Marine Peptides: Bioactivities and Applications

    PubMed Central

    Cheung, Randy Chi Fai; Ng, Tzi Bun; Wong, Jack Ho

    2015-01-01

    Peptides are important bioactive natural products which are present in many marine species. These marine peptides have high potential nutraceutical and medicinal values because of their broad spectra of bioactivities. Their antimicrobial, antiviral, antitumor, antioxidative, cardioprotective (antihypertensive, antiatherosclerotic and anticoagulant), immunomodulatory, analgesic, anxiolytic anti-diabetic, appetite suppressing and neuroprotective activities have attracted the attention of the pharmaceutical industry, which attempts to design them for use in the treatment or prevention of various diseases. Some marine peptides or their derivatives have high commercial values and had reached the pharmaceutical and nutraceutical markets. A large number of them are already in different phases of the clinical and preclinical pipeline. This review highlights the recent research in marine peptides and the trends and prospects for the future, with special emphasis on nutraceutical and pharmaceutical development into marketed products. PMID:26132844

  13. Skin lesion aspiration

    MedlinePLUS

    Skin lesion aspiration is the withdrawal of fluid from a skin lesion (sore). ... A needle is put into skin sore or skin abscess , which may contain fluid or pus. The fluid may be examined under a microscope. A sample of ...

  14. Versatile approach to Rb vapor cell construction

    SciTech Connect

    Hulbert, John F.; Hurd, Katie B.; Carroll, Brandon T.; Hawkins, Aaron R.; Wu, Bin; Schmidt, Holger

    2011-05-15

    A versatile approach to Rb atomic vapor cell construction is proposed and tested. The construction method employs pinch-off copper cold-welds and epoxy to create hermetic seals between dissimilar geometries and materials. Accelerated testing revealed expected lifetimes of 3 days at 90 deg. C operation and in excess of 1 yr at 25 deg. C operation. The reaction of Rb with epoxy was determined to be the largest contributor to failure.

  15. [Bioactive compounds from marine actinomycetes].

    PubMed

    Mikha?lov, V V; Kuznetsova, T A; Eliakov, G B

    1995-01-01

    Studies of the origin of bioactive metabolites of marine actinomycetes are reviewed. Structures and properties of new metabolites from indigenous marine bacteria from Actinomycetales order, such as a benzanthraquinone antibiotic from a strain of the Chainia purpurogena, istamycins, aplasmomycins, altemicidin, new phenazine esters. C13-butanolide, marinone and debromomarinone, palmyromycin, urauchimicins and some others compounds are presented. Prospects of marine biotechnology and microbiology (with considerable emphasis on the development of the basis biology of marine microorganisms in cultures collection) are discussed. PMID:7710421

  16. Aging Skin

    MedlinePLUS

    ... 10 a.m. and 3 p.m. Use sunscreen that has a high SPF number (15 or higher). It should also protect your skin from both UVA and UVB rays. Experts recommend using sunscreen daily, year-round — especially on your face. If you're out in the sun for a long time, protect your ears and scalp with a hat. For ...

  17. A review of bioactive glasses: Their structure, properties, fabrication and apatite formation.

    PubMed

    Kaur, Gurbinder; Pandey, Om P; Singh, Kulvir; Homa, Dan; Scott, Brian; Pickrell, Gary

    2014-01-01

    Bioactive glass and glass-ceramics are used in bone repair applications and are being developed for tissue engineering applications. Bioactive glasses/Bioglass are very attractive materials for producing scaffolds devoted to bone regeneration due to their versatile properties, which can be properly designed depending on their composition. An important feature of bioactive glasses, which enables them to work for applications in bone tissue engineering, is their ability to enhance revascularization, osteoblast adhesion, enzyme activity and differentiation of mesenchymal stem cells as well as osteoprogenitor cells. An extensive amount of research work has been carried out to develop silicate, borate/borosilicate bioactive glasses and phosphate glasses. Along with this, some metallic glasses have also been investigated for biomedical and technological applications in tissue engineering. Many trace elements have also been incorporated in the glass network to obtain the desired properties, which have beneficial effects on bone remodeling and/or associated angiogenesis. The motivation of this review is to provide an overview of the general requirements, composition, structure-property relationship with hydroxyapatite formation and future perspectives of bioglasses.Attention has also been given to developments of metallic glasses and doped bioglasses along with the techniques used for their fabrication. PMID:23468256

  18. Cutaneous skin tag

    MedlinePLUS

    Skin tag; Acrochordon; Fibroepithelial polyp ... have diabetes. They are thought to occur from skin rubbing against skin. ... The tag sticks out of the skin and may have a short, narrow stalk connecting it to the surface of the skin. Some skin tags are as long as ...

  19. Current and potential uses of bioactive molecules from marine processing waste.

    PubMed

    Suleria, Hafiz Ansar Rasul; Masci, Paul; Gobe, Glenda; Osborne, Simone

    2016-03-01

    Food industries produce huge amounts of processing waste that are often disposed of incurring expenses and impacting upon the environment. For these and other reasons, food processing waste streams, in particular marine processing waste streams, are gaining popularity amongst pharmaceutical, cosmetic and nutraceutical industries as sources of bioactive molecules. In the last 30 years, there has been a gradual increase in processed marine products with a concomitant increase in waste streams that include viscera, heads, skins, fins, bones, trimmings and shellfish waste. In 2010, these waste streams equated to approximately 24 million tonnes of mostly unused resources. Marine processing waste streams not only represent an abundant resource, they are also enriched with structurally diverse molecules that possess a broad panel of bioactivities including anti-oxidant, anti-coagulant, anti-thrombotic, anti-cancer and immune-stimulatory activities. Retrieval and characterisation of bioactive molecules from marine processing waste also contributes valuable information to the vast field of marine natural product discovery. This review summarises the current use of bioactive molecules from marine processing waste in different products and industries. Moreover, this review summarises new research into processing waste streams and the potential for adoption by industries in the creation of new products containing marine processing waste bioactives. © 2015 Society of Chemical Industry. PMID:26332893

  20. Bioactive glass-coated silicone for percutaneous devices with improved tissue interaction

    NASA Astrophysics Data System (ADS)

    Marotta, James Scott

    The discovery of bioactive glasses, in the early 1970s, has produced a material that develops a strong adherent bond with soft tissue. Many medical applications currently use silicone as an implant material, but are hindered by the formation of fibrous scar tissue surrounding the device. This fibrous scar tissue can lead to pain, infection, and/or extrusion of these devices. Bioactive ceramic materials are inherently brittle and can not be used in applications where a flexible material is needed. Therefore, the coating of existing flexible silicone medical devices, like catheters, with a bioactive glass material would give the advantages of both. The research presented here is of methods used to coat silicone with a bioactive glass powder (Bioglassler) and the in vitro testing of those coatings. The bioactivity of these coatings was measured using scanning electron microscopy, inductively coupled plasma spectroscopy, and Fourier transform infrared spectroscopy. It was observed that hydroxyapatite, a bonelike apatite, was formed in vitro on both the bioactive glass particles and the silicone surface between these particles. From these results a new theory was developed that related the distance between particles on a surface with the formation of an apatite layer. A critical distance between particles for the formation of an apatite layer on the substrate exists. This critical distance is a function of both the particle size and composition. In addition, a method to coat silicone catheters with bioactive glass powder is also discussed. This coated catheter could ultimately be used for improved percutaneous access in peritoneal dialysis. The one barrier to greater peritoneal dialysis use and the reason many patients switch from peritoneal to hemodialysis is recurrent exit-site infections and subsequent peritonitis. These infections are caused by the lack of a tight seal and downgrowth of epidermal tissue around the catheter at the catheter-skin interface.

  1. Skin deep.

    PubMed

    Hadgraft, Jonathan

    2004-09-01

    Over the past 30 or so years there has been a considerable advance in our knowledge of the mechanisms of skin permeation. This has largely been brought about by the development of sophisticated biophysical techniques and increased computing powers. The advanced technology has clearly provided indications, at a molecular level, about routes of permeation and how the barrier function can be modulated by excipients with which actives are formulated. This publication reviews some of the advances that have been made and mathematical models that have been constructed to predict percutaneous penetration and transdermal delivery. The models also indicate the various enhancement strategies that can be used in dermal penetration. In the past, it has been difficult to identify precise mechanisms of action of the different classes of enhancer but a combination of appropriate biophysical techniques, mathematical modelling and chemometric analysis can help identify the contributing processes. The models can also be used to indicate rate control in transdermal delivery, whether it is in the applied delivery device or in the skin. PMID:15296956

  2. Bioactivity of electro-thermally poled bioactive silicate glass.

    PubMed

    Mariappan, C R; Yunos, D M; Boccaccini, A R; Roling, B

    2009-05-01

    A 45S5 bioactive glass (nominal composition: 46.1 mol.% SiO2, 2.6 mol.% P2O5, 26.9 mol.% CaO, 24.4 mol.% Na2O) was electrothermally poled by applying voltages up to 750 V for 45 min at 200 degrees C, and the thermally stimulated depolarization currents (TSDCs) were recorded. Changes in chemical composition and electrical properties after poling were investigated by TSDC measurements, impedance spectroscopy and scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM/EDX). The poling led to the formation of interfacial layers underneath the surface in contact with the electrodes. Under the positive electrode, the layer was characterized by Na+ ion depletion and by a negative charge density, and the layer was more resistive than the bulk. The influence of poling on the bioactivity was studied by immersion of samples in simulated body fluid (SBF) with subsequent cross-sectional SEM/EDX and X-ray diffraction analysis. It was found that poling leads to morphological changes in the silica-rich layer and to changes in the growth rate of amorphous calcium phosphate and bone-like apatite on the glass surface. The bone-like apatite layer under the positive electrode was slightly thicker than that under the negative electrode. PMID:19097952

  3. A Versatile Rocket Engine Hot Gas Facility

    NASA Technical Reports Server (NTRS)

    Green, James M.

    1993-01-01

    The capabilities of a versatile rocket engine facility, located in the Rocket Laboratory at the NASA Lewis Research Center, are presented. The gaseous hydrogen/oxygen facility can be used for thermal shock and hot gas testing of materials and structures as well as rocket propulsion testing. Testing over a wide range of operating conditions in both fuel and oxygen rich regimes can be conducted, with cooled or uncooled test specimens. The size and location of the test cell provide the ability to conduct large amounts of testing in short time periods with rapid turnaround between programs.

  4. Toward bioactive yet antibacterial surfaces.

    PubMed

    Sukhorukova, I V; Sheveyko, A N; Kiryukhantsev-Korneev, Ph V; Zhitnyak, I Y; Gloushankova, N A; Denisenko, E A; Filippovich, S Yu; Ignatov, S G; Shtansky, D V

    2015-11-01

    The fabrication of antibacterial yet biocompatible and bioactive surfaces is a challenge that biological and biomedical community has faced for many years, while no "dream material" has been developed so far. The primary goal of this study was to establish an optimal range of Ag concentration and its state of agglomeration in bioactive nanocomposite TiCaPCON films which would provide a strong bactericidal effect without compromising the material biocompatibility and bioactivity. To obtain samples with different Ag content and redistribution, two different methods were employed: (i) TiCaPCON films deposition by magnetron sputtering of composite Ti?0.5-Ca3(??4)2 target followed by Ag(+) ion implantation and (ii) Ag-doped TiCaPCON films obtained by co-sputtering of composite Ti?0.5-Ca3(??4)2 and Ag targets. In order to reveal the antibacterial role of Ag nanoparticles and Ag(+) ions, both separate and in synergy, part of the samples from the first and second groups was subjected to additional ion etching to remove an Ag rich surface layer heavily populated with Ag nanoparticles. All resultant films were characterized with respect to surface morphology, chemical composition, surface roughness, wettability, and Ag(+) ion release. The antibacterial and antifungal effects of the Ag-doped TiCaPCON films were evaluated against clinically isolated Escherichia coli O78 (E. coli) and Neurospora crassa wt-987 spores. The influence of the surface chemistry on spreading, proliferation, and early stages of MC3T3-E1 osteoblastic cell differentiation was also studied. Our data demonstrated that under optimal conditions in terms of Ag content and agglomeration, the Ag-doped TiCaPCON films are highly efficient against E. coli bacteria and, at the same time, provide good adhesion, spreading, proliferation and differentiation of osteoblastic cells which reflect high level of biocompatibility and bioactivity of the films. The influence of Ag(+) ions and nanoparticles on the MC3T3-E1 osteoblastic cells and E. coli bacteria is also discussed. PMID:26255161

  5. Quinazoline derivatives: synthesis and bioactivities

    PubMed Central

    2013-01-01

    Owing to the significant biological activities, quinazoline derivatives have drawn more and more attention in the synthesis and bioactivities research. This review summarizes the recent advances in the synthesis and biological activities investigations of quinazoline derivatives. According to the main method the authors adopted in their research design, those synthetic methods were divided into five main classifications, including Aza-reaction, Microwave-assisted reaction, Metal-mediated reaction, Ultrasound-promoted reaction and Phase-transfer catalysis reaction. The biological activities of the synthesized quinazoline derivatives also are discussed. PMID:23731671

  6. Bioactive thiazole and benzothiazole derivatives.

    PubMed

    Rouf, Abdul; Tanyeli, Cihangir

    2015-06-01

    The heterocycles are the versatile compounds existing in almost all natural products and synthetic organic compounds, usually associated with one or the other biological activity. Among the heterocycles the thiazoles and benzothiazoles occupy a prominent position. They possess a broad range of biological activities and are found in many potent biologically active molecules and drugs such as vitamin thiamine, sulfathiazol (antimicrobial drug), ritonavir (antiretroviral drug), abafungin (antifungal drug) and tiazofurin (antineoplastic drug). The thiazole moiety is abundantly found in natural products while benzothiazole moiety is rare. In this review we disclose the literature reports of thiazoles and benzothiazoles possessing different biological activities. PMID:25455640

  7. Multilayer network decoding versatility and trust

    NASA Astrophysics Data System (ADS)

    Sarkar, Camellia; Yadav, Alok; Jalan, Sarika

    2016-01-01

    In the recent years, the multilayer networks have increasingly been realized as a more realistic framework to understand emergent physical phenomena in complex real-world systems. We analyze massive time-varying social data drawn from the largest film industry of the world under a multilayer network framework. The framework enables us to evaluate the versatility of actors, which turns out to be an intrinsic property of lead actors. Versatility in dimers suggests that working with different types of nodes are more beneficial than with similar ones. However, the triangles yield a different relation between type of co-actor and the success of lead nodes indicating the importance of higher-order motifs in understanding the properties of the underlying system. Furthermore, despite the degree-degree correlations of entire networks being neutral, multilayering picks up different values of correlation indicating positive connotations like trust, in the recent years. The analysis of weak ties of the industry uncovers nodes from a lower-degree regime being important in linking Bollywood clusters. The framework and the tools used herein may be used for unraveling the complexity of other real-world systems.

  8. Versatile smart optical material characterizer system

    NASA Astrophysics Data System (ADS)

    Park, Yeonjoon; Park, SangJoon; Lee, Uhn; Lee, Kunik; Choi, Sang

    2010-04-01

    A versatile optical characterization system is fabricated to measure various optical properties of materials and devices. The optical system is based on Michelson interferometer with advanced software algorithm to measure the intensity, phase angle, polarization state, and coherence of transmitted or reflected light from the materials and devices under test. Innovative contour map of phase/intensity vs. time/physical-quantity relation shows the dynamic evolution of interference patterns of multiple points in the analysis area. Advanced software semi-automatically calculates change of photon intensity, phase angle, polarization, and coherence which are results of various applied physical quantities such as voltage, electric field, current, temperature, pressure, chemical density, and reaction time. The measured optical property changes are converted by software to the changes of intrinsic and extrinsic properties of materials and devices under test. The system is designed for multi-point measurements which are suitable for 2D-array-pixel type devices. Therefore, this versatile optical measurement system can accelerate the development of advanced adaptive optics elements and phase control elements.

  9. A Versatile Ion Injector at KACST

    SciTech Connect

    El Ghazaly, M. O. A.; Behery, S. A.; Almuqhim, A. A.; Papash, A. I.; Welsch, C. P.

    2011-10-27

    A versatile ion-beam injector is presently being constructed at the National Centre for Mathematics and Physics (NCMP) at the King Abdul-Aziz City for Science and Technology (KACST), Saudi Arabia. This versatile injector will provide an electrostatic storage ring with high-quality ion beams of energies up to 30 keV per charge q. It will also allow for crossed-beams experiments in single-pass setups. The injector has been designed to include beams from two different ion sources, switched by a 90 deg. deflection setup, and to allow for matching of the beam parameters to the Twiss parameters of the ring. The injector is equipped with two crossed beam-lines (inlets), with duplicated beam extraction and acceleration systems. As part of the initial setup, a simple electric discharge ion source has been developed for commissioning of the whole injector. In this paper, we report on the ion optics layout and the design parameters of the injector.

  10. Bioactivity of plasma implanted biomaterials

    NASA Astrophysics Data System (ADS)

    Chu, Paul K.

    2006-01-01

    Plasma immersion ion implantation and deposition (PIII&D) is an effective technique to enhance the surface bioactivity of materials. In this paper, recent progress made in our laboratory on plasma surface modification of biomedical materials is described. NiTi alloys have unique super-elastic and shape memory properties and are suitable for orthopedic implants but the leaching of toxic Ni may pose health hazards in humans. We have recently investigated the use of acetylene, oxygen and nitrogen PIII&D to prevent out-diffusion of nickel and good results have been obtained. Silicon is the most important material in the microelectronics industry but its surface biocompatibility has not been investigated in details. We have recently performed hydrogen PIII into silicon to improve the surface bioactivity and observed biomimetic growth of apatite on the surface in simulated body fluids. Diamond-like carbon (DLC) is widely used in the industry due to its excellent mechanical properties and chemical inertness and by incorporation of elements such as nitrogen and phosphorus, the surface blood compatibility can be improved. The properties as well as in vitro biological test results are discussed in this article.

  11. Bioactive Egg Components and Inflammation

    PubMed Central

    Andersen, Catherine J.

    2015-01-01

    Inflammation is a normal acute response of the immune system to pathogens and tissue injury. However, chronic inflammation is known to play a significant role in the pathophysiology of numerous chronic diseases, such as cardiovascular disease, type 2 diabetes mellitus, and cancer. Thus, the impact of dietary factors on inflammation may provide key insight into mitigating chronic disease risk. Eggs are recognized as a functional food that contain a variety of bioactive compounds that can influence pro- and anti-inflammatory pathways. Interestingly, the effects of egg consumption on inflammation varies across different populations, including those that are classified as healthy, overweight, metabolic syndrome, and type 2 diabetic. The following review will discuss the pro- and anti-inflammatory properties of egg components, with a focus on egg phospholipids, cholesterol, the carotenoids lutein and zeaxanthin, and bioactive proteins. The effects of egg consumption of inflammation across human populations will additionally be presented. Together, these findings have implications for population-specific dietary recommendations and chronic disease risk. PMID:26389951

  12. Bioactive Components in Fish Venoms

    PubMed Central

    Ziegman, Rebekah; Alewood, Paul

    2015-01-01

    Animal venoms are widely recognized excellent resources for the discovery of novel drug leads and physiological tools. Most are comprised of a large number of components, of which the enzymes, small peptides, and proteins are studied for their important bioactivities. However, in spite of there being over 2000 venomous fish species, piscine venoms have been relatively underrepresented in the literature thus far. Most studies have explored whole or partially fractioned venom, revealing broad pharmacology, which includes cardiovascular, neuromuscular, cytotoxic, inflammatory, and nociceptive activities. Several large proteinaceous toxins, such as stonustoxin, verrucotoxin, and Sp-CTx, have been isolated from scorpaenoid fish. These form pores in cell membranes, resulting in cell death and creating a cascade of reactions that result in many, but not all, of the physiological symptoms observed from envenomation. Additionally, Natterins, a novel family of toxins possessing kininogenase activity have been found in toadfish venom. A variety of smaller protein toxins, as well as a small number of peptides, enzymes, and non-proteinaceous molecules have also been isolated from a range of fish venoms, but most remain poorly characterized. Many other bioactive fish venom components remain to be discovered and investigated. These represent an untapped treasure of potentially useful molecules. PMID:25941767

  13. Skin self-exam

    MedlinePLUS

    Skin self-exam means checking your own skin regularly for any abnormal growths or unusual changes. A skin self-exam helps find any suspicious skin problems early. The earlier skin cancer is diagnosed, the better chance you will have ...

  14. CSD skin test

    MedlinePLUS

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  15. Skin graft - series (image)

    MedlinePLUS

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  16. Skin layers (image)

    MedlinePLUS

    The skin is the largest organ of the body. The skin and its derivatives (hair, nails, sweat and oil ... system. One of the main functions of the skin is protection. It protects the body from external ...

  17. Skin Condition Finder

    MedlinePLUS

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  18. Skin lesion biopsy

    MedlinePLUS

    Punch biopsy; Shave biopsy; Skin biopsy; Biopsy - skin ... There are several ways to do a skin biopsy. Most procedures can be done in your doctor's office or an outpatient medical office. Which procedure you have depends on the location, ...

  19. Skin Cancer: Atypical Moles

    MedlinePLUS

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  20. Basal cell skin cancer

    MedlinePLUS

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  1. Nutritional compositions and bioactivities of Dacryodes species: a review.

    PubMed

    Tee, Lee Hong; Yang, Bao; Nagendra, Krishnamurthy Prasad; Ramanan, Ramakrishnan Nagasundara; Sun, Jian; Chan, Eng-Seng; Tey, Beng Ti; Azlan, Azrina; Ismail, Amin; Lau, Cheng Yuon; Jiang, Yueming

    2014-12-15

    Dacryodes species are evergreen, perennial trees with fleshy fruits and belong to the family Buseraseae. Many Dacryodes species are underutilized but are widely applied in traditional folk medicine to treat malaria, fever and skin diseases. The nutritional compositions, phytochemicals and biological activities of Dacryodes edulis, Dacryodes rostrata, Dacryodes buettneri, Dacryodes klaineana and Dacryodes hexandra are presented. The edible fruits of D. edulis are rich in lipids, proteins, vitamins, fatty acids and amino acids. Its extracts (leaf, fruit and resin) exhibit antioxidant, anti-microbial, anti-carcinogenic and other bioactivities. D. rostrata fruit has significant nutrient content, and is rich in proteins, lipids and minerals. These fruits are also highly rich in polyphenols, anthocyanins and antioxidant activities. This comprehensive review will assist the reader in understanding the nutritional benefits of Dacryodes species and in identifying current research needs. PMID:25038673

  2. Marine fish-derived bioactive peptides as potential antihypertensive agents.

    PubMed

    Kim, Se-Kwon; Ngo, Dai-Hung; Vo, Thanh-Sang

    2012-01-01

    Hypertension is the most widespread risk factor for many serious cardiovascular diseases. Angiotensin-converting enzyme (ACE) plays a crucial role in cardiovascular physiological regulation by converting angiotensin I to a potent vasoconstrictor, angiotensin II. Hence, the inhibition of ACE is a key target for antihypertensive activity. Recently, potent antihypertensive peptides have been purified widely by enzymatic hydrolysis of muscle protein, skin collagen, and gelatin of many different kinds of marine fishes. Marine fish-derived bioactive peptides can be developed as antihypertensive components in functional foods or nutraceuticals. This contribution presents an overview of the ACE inhibitory peptides derived from marine fishes and discusses their future prospects to be used as potential drug candidates for preventing and treating high blood pressure. PMID:22361192

  3. Versatile UHV compatible Knudsen type effusion cell

    SciTech Connect

    Shukla, A.K.; Banik, S.; Dhaka, R.S.; Biswas, C.; Barman, S.R.; Haak, H.

    2004-11-01

    A versatile Knudsen type effusion cell has been fabricated for growing nanostructures and epitaxial layers of metals and semiconductors. The cell provides excellent vacuum compatibility (10{sup -10} mbar range during operation), efficient water cooling, uniform heating, and moderate input power consumption (100 W at 1000 deg. C). The thermal properties of the cell have been determined. The performance of the cell has been assessed by x-ray photoemission spectroscopy (XPS) for Mn adlayer growth on Al(111). We find that this Knudsen cell has a stable deposition rate of 0.17 monolayer per minute at 550 deg. C. From the XPS spectra, we show that the Mn adlayers are completely clean, i.e., devoid of any surface contamination.

  4. Functional versatility supports coral reef biodiversity

    PubMed Central

    Bellwood, D.R; Wainwright, P.C; Fulton, C.J; Hoey, A.S

    2005-01-01

    We explore the role of specialization in supporting species coexistence in high-diversity ecosystems. Using a novel ordination-based method to quantify specialist and generalist feeding structures and diets we examined the relationship between morphology and diet in 120 wrasses and parrotfishes from the Great Barrier Reef. We find that wrasses, despite their morphological diversity, exhibit weak links between morphology and diet and that specialist morphologies do not necessarily equate to specialized diets. The dominant pattern shows extensive overlap in morphology (functional morphospace occupation) among trophic groups; fish with a given morphology may have a number of feeding modes. Such trophic versatility may lay the foundation for both the origins and maintenance of high biodiversity on coral reefs. PMID:16519241

  5. Versatile microcomputer-based temperature controller

    SciTech Connect

    Yarberry, V.R.

    1980-09-01

    The wide range of thermal responses required in laboratory and scientific equipment requires a temperature controller with a great deal of flexibility. While a number of analog temperature controllers are commercially available, they have certain limitations, such as inflexible parameter control or insufficient precision. Most lack digital interface capabilities--a necessity when the temperature controller is part of a computer-controlled automatic data acquisition system. We have developed an extremely versatile microcomputer-based temperature controller to fulfill this need in a variety of equipment. The control algorithm used allows optimal tailoring of parameters to control overshoot, response time, and accuracy. This microcomputer-based temperature controller can be used as a standalone instrument (with a teletype used to enter para-meters), or it can be integrated into a data acquisition system (with a computer used to pass parameters by way of an IEE-488 instrumentation bus).

  6. The Versatile Link common project: feasibility report

    NASA Astrophysics Data System (ADS)

    Vasey, F.; Hall, D.; Huffman, T.; Kwan, S.; Prosser, A.; Soos, C.; Troska, J.; Weidberg, T.; Xiang, A.; Ye, J.

    2012-01-01

    The Versatile Link is a bi-directional digital optical data link operating at rates up to 4.8 Gbit/s and featuring radiation-resistant low-power and low-mass front-end components. The system is being developed in multimode or singlemode versions operating at 850 nm or 1310 nm wavelength respectively. It has serial data interfaces and is protocol-agnostic, but is targeted to operate in tandem with the GigaBit Transceiver (GBT) serializer/deserializer chip being designed at CERN. This paper gives an overview of the project status three and a half years after its launch. It describes the challenges encountered and highlights the solutions proposed at the system as well as the component level. It concludes with a positive feasibility assesment and an outlook for future project development directions.

  7. Versatile organic transistors by solution processing.

    PubMed

    Ward, Jeremy W; Lamport, Zachary A; Jurchescu, Oana D

    2015-04-27

    A selection of the latest developments in organic electronic materials and organic field-effect transistor (OFET) devices is reviewed here with an emphasis on the synthetic and manufacturing versatility, ease of processing, and low cost offered by solution processability. At the heart of these benefits is the nature of the weak van der Waals intermolecular interactions inherent to organic compounds. This allows processability with a relatively small amount of energy investment. Material solubility, in particular, creates unique pathways for film fabrication and the design of new device architectures, while presenting new manufacturing challenges to explore. In this review we provide a chronological presentation of the important developments in the solution-deposited organic small-molecule semiconductor, dielectric, and electrode materials used in OFETs, making specific note of current benchmarks. Organic device architectures and fabrication methods that are characterized by reduced complexity and ease of implementation are discussed. PMID:25757210

  8. Bioactive composite materials for tissue engineering scaffolds.

    PubMed

    Boccaccini, Aldo R; Blaker, Jonny J

    2005-05-01

    Synthetic bioactive and bioresorbable composite materials are becoming increasingly important as scaffolds for tissue engineering. Next-generation biomaterials should combine bioactive and bioresorbable properties to activate in vivo mechanisms of tissue regeneration, stimulating the body to heal itself and leading to replacement of the scaffold by the regenerating tissue. Certain bioactive ceramics such as tricalcium phosphate and hydroxyapatite as well as bioactive glasses, such as 45S5 Bioglass, react with physiologic fluids to form tenacious bonds with hard (and in some cases soft) tissue. However, these bioactive materials are relatively stiff, brittle and difficult to form into complex shapes. Conversely, synthetic bioresorbable polymers are easily fabricated into complex structures, yet they are too weak to meet the demands of surgery and the in vivo physiologic environment. Composites of tailored physical, biologic and mechanical properties as well as predictable degradation behavior can be produced combining bioresorbable polymers and bioactive inorganic phases. This review covers recent international research presenting the state-of-the-art development of these composite systems in terms of material constituents, fabrication technologies, structural and bioactive properties, as well as in vitro and in vivo characteristics for applications in tissue engineering and tissue regeneration. These materials may represent the effective optimal solution for tailored tissue engineering scaffolds, making tissue engineering a realistic clinical alternative in the near future. PMID:16288594

  9. Investigating the protective properties of milk phospholipids against ultraviolet light exposure in a skin equivalent model

    NASA Astrophysics Data System (ADS)

    Russell, Ashley; Laubscher, Andrea; Jimenez-Flores, Rafael; Laiho, Lily H.

    2010-02-01

    Current research on bioactive molecules in milk has documented health advantages of bovine milk and its components. Milk Phospholipids, selected for this study, represent molecules with great potential benefit in human health and nutrition. In this study we used confocal reflectance and multiphoton microscopy to monitor changes in skin morphology upon skin exposure to ultraviolet light and evaluate the potential of milk phospholipids in preventing photodamage to skin equivalent models. The results suggest that milk phospholipids act upon skin cells in a protective manner against the effect of ultraviolet (UV) radiation. Similar results were obtained from MTT tissue viability assay and histology.

  10. Bioactive Hybrid Particles from Poly(D,L-lactide-co-glycolide) Nanoparticle Stabilized Lipid Droplets.

    PubMed

    Joyce, Paul; Whitby, Catherine P; Prestidge, Clive A

    2015-08-12

    Biodegradable and bioactive hybrid particles composed of poly(D,L-lactide-co-glycolide) (PLGA) nanoparticles and medium-chain triglycerides were prepared by spray drying lipid-in-water emulsions stabilized by PLGA nanoparticles, to form PLGA-lipid hybrid (PLH) microparticles approximately 5 μm in mean diameter. The nanoparticle stabilizer was varied and mannitol was also incorporated during the preparation to investigate the effect of stabilizer charge and cryoprotectant content on the particle microstructure. An in vitro lipolysis model was used to demonstrate the particles' bioactivity by manipulating the digestion kinetics of encapsulated lipid by pancreatic lipase in simulated gastrointestinal fluid. Lipid digestion kinetics were enhanced in PLH and PLGA-lipid-mannitol hybrid (PLMH) microparticles for both stabilizers, compared to a coarse emulsion, in biorelevant media. An optimal digestion rate was observed for the negatively charged PLMH system, evidenced by a 2-fold increase in the pseudo-first-order rate constant compared to a coarse emulsion. Improved microparticle redispersion, probed by dual dye confocal fluorescence microscopy, increased the available surface area of lipid for lipase adsorption, enhancing digestion kinetics. Thereby, lipase action was controlled in hybrid microparticles by altering the surface charge and carbohydrate content. Our results demonstrate that bioactive microparticles composed of versatile and biodegradable polymeric particles and oil droplets have great potential for use in smart food and nutrient delivery, as well as safer and more efficacious oral delivery of drugs and drug combinations. PMID:26181279

  11. Bioactive factor delivery strategies from engineered polymer hydrogels for therapeutic medicine

    PubMed Central

    Nguyen, Minh Khanh; Alsberg, Eben

    2014-01-01

    Polymer hydrogels have been widely explored as therapeutic delivery matrices because of their ability to present sustained, localized and controlled release of bioactive factors. Bioactive factor delivery from injectable biopolymer hydrogels provides a versatile approach to treat a wide variety of diseases, to direct cell function and to enhance tissue regeneration. The innovative development and modification of both natural-(e.g., alginate (ALG), chitosan, hyaluronic acid (HA), gelatin, heparin (HEP), etc.) and synthetic-(e.g., polyesters, polyethyleneimine (PEI), etc.) based polymers has resulted in a variety of approaches to design drug delivery hydrogel systems from which loaded therapeutics are released. This review presents the state-of-the-art in a wide range of hydrogels that are formed though self-assembly of polymers and peptides, chemical crosslinking, ionic crosslinking and biomolecule recognition. Hydrogel design for bioactive factor delivery is the focus of the first section. The second section then thoroughly discusses release strategies of payloads from hydrogels for therapeutic medicine, such as physical incorporation, covalent tethering, affinity interactions, on demand release and/or use of hybrid polymer scaffolds, with an emphasis on the last 5 years. PMID:25242831

  12. Sol-gel derived porous bioactive nanocomposites: Synthesis and in vitro bioactivity

    NASA Astrophysics Data System (ADS)

    Shankhwar, Nisha; Kothiyal, G. P.; Srinivasan, A.

    2013-06-01

    Porous bioactive composites consisting of SiO2-CaO-Na2O-P2O5 bioactive glass-ceramic and synthetic water soluble polymer Polyvinylpyrrolidone [PVP (C6H9NO)n, MW˜40000 g/mol] have been synthesized by sol-gel route. As-prepared polymeric composites were characterized by X-ray diffraction (XRD) technique. Two major bone mineral phases, viz., hydroxyapatite [Ca10(PO4)6(OH)2] and wollastonite [calcium silicate (CaSiO3)] have been identified in the XRD patterns of the composites. Presence of these bone minerals indicates the bioactive nature of the composites. In vitro bioactivity tests confirm bioactivity in the porous composites. The flexibility offered by these bioactive polymer composites is advantageous for its application as implant material.

  13. Bioactive Carbohydrates and Peptides in Foods: An Overview of Sources, Downstream Processing Steps and Associated Bioactivities

    PubMed Central

    Hayes, Maria; Tiwari, Brijesh K.

    2015-01-01

    Bioactive peptides and carbohydrates are sourced from a myriad of plant, animal and insects and have huge potential for use as food ingredients and pharmaceuticals. However, downstream processing bottlenecks hinder the potential use of these natural bioactive compounds and add cost to production processes. This review discusses the health benefits and bioactivities associated with peptides and carbohydrates of natural origin and downstream processing methodologies and novel processes which may be used to overcome these. PMID:26393573

  14. Bioactive Carbohydrates and Peptides in Foods: An Overview of Sources, Downstream Processing Steps and Associated Bioactivities.

    PubMed

    Hayes, Maria; Tiwari, Brijesh K

    2015-01-01

    Bioactive peptides and carbohydrates are sourced from a myriad of plant, animal and insects and have huge potential for use as food ingredients and pharmaceuticals. However, downstream processing bottlenecks hinder the potential use of these natural bioactive compounds and add cost to production processes. This review discusses the health benefits and bioactivities associated with peptides and carbohydrates of natural origin and downstream processing methodologies and novel processes which may be used to overcome these. PMID:26393573

  15. Urostomy - stoma and skin care

    MedlinePLUS

    ... it well before you attach the pouch. Avoid skin care products that contain alcohol. These can make your skin ... the pouch to your skin. Use fewer special skin care products. This will make problems with your skin less ...

  16. [Bioactive peptides derived from milk proteins].

    PubMed

    Torres-Llanez, María de Jesús; Vallejo-Cordoba, Belinda; González-Córdova, Aaron Fernando

    2005-06-01

    Milk proteins are known for having a wide range of nutritional, functional and biological properties that make them important ingredients in functional or health promoting foods. These properties are partly attributed to bioactive peptides coded in the different milk proteins. Bioactive peptides are inactive within the protein sequence but may be released by the action of native proteolitic enzymes from milk, enzymes from lactic acid bacteria or from exogenous sources or may be produced during gastrointestinal digestion or processing of foods. Peptides derived from caseins and whey proteins were shown to present several bioactive properties such as opioid, antihypertensive, antimicrobial, immunodulatory, mineral carrier and antithrombotic. This overview presents a perspective of the importance of dairy proteins in the production of bioactive peptides and their biological activities, as well as the main analytical tecniques that have been used for the isolation and identification of these peptides. PMID:16335219

  17. The inhibitory effect of natural bioactives on the growth of pathogenic bacteria

    PubMed Central

    Kim, Ji-Sun

    2007-01-01

    The objective of this study was to evaluate the inhibitory activity of natural products, against growth of Escherichia coli (ATCC 25922) and Salmonella typhimurium (KCCM 11862). Chitosan, epigallocatechin gallate (EGCG), and garlic were used as natural bioactives for antibacterial activity. The testing method was carried out according to the disk diffusion method. All of chitosan, EGCG, and garlic showed inhibitory effect against the growth of E. coli and Salmonella typhi. To evaluate the antibacterial activity of natural products during storage, chicken skins were inoculated with 106 of E. coli or Salmonella typhi. The inoculated chicken skins, treated with 0.5, 1, or 2% natural bioactives, were stored during 8 day at 4?. The numbers of microorganisms were measured at 8 day. Both chitosan and EGCG showed significant decrease in the number of E. coli and Salmonella typhi in dose dependent manner (P < 0.05). These results suggest that natural bioactives such as chitosan, EGCG may be possible to be used as antimicrobial agents for the improvement of food safety. PMID:20368950

  18. Natural Bioactive Compounds from Winery By-Products as Health Promoters: A Review

    PubMed Central

    Teixeira, Ana; Baenas, Nieves; Dominguez-Perles, Raul; Barros, Ana; Rosa, Eduardo; Moreno, Diego A.; Garcia-Viguera, Cristina

    2014-01-01

    The relevance of food composition for human health has increased consumers’ interest in the consumption of fruits and vegetables, as well as foods enriched in bioactive compounds and nutraceuticals. This fact has led to a growing attention of suppliers on reuse of agro-industrial wastes rich in healthy plant ingredients. On this matter, grape has been pointed out as a rich source of bioactive compounds. Currently, up to 210 million tons of grapes (Vitis vinifera L.) are produced annually, being the 15% of the produced grapes addressed to the wine-making industry. This socio-economic activity generates a large amount of solid waste (up to 30%, w/w of the material used). Winery wastes include biodegradable solids namely stems, skins, and seeds. Bioactive compounds from winery by-products have disclosed interesting health promoting activities both in vitro and in vivo. This is a comprehensive review on the phytochemicals present in winery by-products, extraction techniques, industrial uses, and biological activities demonstrated by their bioactive compounds concerning potential for human health. PMID:25192288

  19. Adhesion and spreading of osteoblast-like cells on surfaces coated with laminin-derived bioactive core peptides

    PubMed Central

    Yeo, In-Sung; Min, Seung-Ki; Ki Kang, Hyun; Kwon, Taek-Ka; Youn Jung, Sung; Min, Byung-Moo

    2015-01-01

    Functional peptides are attractive as novel therapeutic reagents because their amino acid sequences are flexible in adopting and mimicking the local functional features of proteins. These peptides are of low molecular weight, synthetically versatile and inexpensive to produce, suggesting that they can be used as drug targeting, potent, stable and bioavailable agents. A short bioactive peptide is expected to be more beneficial in regenerative medicine than an entire protein because of the lower antigenicity of short amino acid sequences. We detected core peptides from human laminin that are involved in adhesion and spreading, which are the first steps of various cells including osteogenic cells, in becoming functional. In this experiment, we detected adhesion and spreading of osteoblast-like cells seeded on the core peptide-coated surface. These in vitro data are related to the research article, entitled “Identification of a bioactive core sequence from human laminin and its applicability to tissue engineering” (Yeo et al., 2015) [1].

  20. Bioactivity-guided study of antiproliferative activities of Salvia extracts.

    PubMed

    Janicsk, Gbor; Zupk, Istvn; Nikolovac, Milena T; Forgo, Peter; Vasas, Andrea; Math, Imre; Blunden, Gerald; Hohmann, Judit

    2011-05-01

    The cytotoxic activities of the n-hexane, chloroform and aqueous methanolic fractions prepared from the methanolic extract of the leaves of 23 Salvia taxa were studied for their cell growth-inhibitory activity against human cervix adenocarcinoma (HeLa), skin carcinoma (A431) and breast adenocarcinoma (MCF7) cells using the MTT assay. The n-hexane fractions of six Salvia taxa (S. hispanica, S. nemorosa, S. nemorosa 1. albiflora, S. pratensis, S. recognita and S. ringens) and the chloroform fraction ofS. officinalis 1. albiflora produced over 50% growth inhibition of the skin carcinoma cell line. None of the tested extracts showed substantial (above 50%) antiproliferative effects against HeLa and MCF7 cells. S. ringens was the most powerful among the studied Salvia species with a 61.8% cell growth inhibitory activity on A431 cells. In the case of S. ringens, other plant parts were also tested for antiproliferative effect, and the highest activities were recorded for the root extract. This was subjected to bioactivity-guided fractionation, which yielded four abietane diterpenes (royleanone, horminone, 7-O-methyl-horminone and 7-acetyl-horminone), one triterpene (erythrodiol-3-acetate) and beta-sitosterol. Horminone, 7-acetyl-horminone and erythrodiol-3-acetate displayed marked concentration-dependent antiproliferative effects, while royleanone and 7-O-methyl-horminone produced weaker activities. PMID:21615011

  1. A Versatile Nonlinear Method for Predictive Modeling

    NASA Technical Reports Server (NTRS)

    Liou, Meng-Sing; Yao, Weigang

    2015-01-01

    As computational fluid dynamics techniques and tools become widely accepted for realworld practice today, it is intriguing to ask: what areas can it be utilized to its potential in the future. Some promising areas include design optimization and exploration of fluid dynamics phenomena (the concept of numerical wind tunnel), in which both have the common feature where some parameters are varied repeatedly and the computation can be costly. We are especially interested in the need for an accurate and efficient approach for handling these applications: (1) capturing complex nonlinear dynamics inherent in a system under consideration and (2) versatility (robustness) to encompass a range of parametric variations. In our previous paper, we proposed to use first-order Taylor expansion collected at numerous sampling points along a trajectory and assembled together via nonlinear weighting functions. The validity and performance of this approach was demonstrated for a number of problems with a vastly different input functions. In this study, we are especially interested in enhancing the method's accuracy; we extend it to include the second-orer Taylor expansion, which however requires a complicated evaluation of Hessian matrices for a system of equations, like in fluid dynamics. We propose a method to avoid these Hessian matrices, while maintaining the accuracy. Results based on the method are presented to confirm its validity.

  2. Building versatile bipartite probes for quantum metrology

    NASA Astrophysics Data System (ADS)

    Farace, Alessandro; De Pasquale, Antonella; Adesso, Gerardo; Giovannetti, Vittorio

    2016-01-01

    We consider bipartite systems as versatile probes for the estimation of transformations acting locally on one of the subsystems. We investigate what resources are required for the probes to offer a guaranteed level of metrological performance, when the latter is averaged over specific sets of local transformations. We quantify such a performance via the average skew information (AvSk), a convex quantity which we compute in closed form for bipartite states of arbitrary dimensions, and which is shown to be strongly dependent on the degree of local purity of the probes. Our analysis contrasts and complements the recent series of studies focused on the minimum, rather than the average, performance of bipartite probes in local estimation tasks, which was instead determined by quantum correlations other than entanglement. We provide explicit prescriptions to characterize the most reliable states maximizing the AvSk, and elucidate the role of state purity, separability and correlations in the classification of optimal probes. Our results can help in the identification of useful resources for sensing, estimation and discrimination applications when complete knowledge of the interaction mechanism realizing the local transformation is unavailable, and access to pure entangled probes is technologically limited.

  3. Buried nanoantenna arrays: versatile antireflection coating.

    PubMed

    Kabiri, Ali; Girgis, Emad; Capasso, Federico

    2013-01-01

    Reflection is usually a detrimental phenomenon in many applications such as flat-panel-displays, solar cells, photodetectors, infrared sensors, and lenses. Thus far, to control and suppress the reflection from a substrate, numerous techniques including dielectric interference coatings, surface texturing, adiabatic index matching, and scattering from plasmonic nanoparticles have been investigated. A new technique is demonstrated to manage and suppress reflection from lossless and lossy substrates. It provides a wider flexibility in design versus previous methods. Reflection from a surface can be suppressed over a narrowband, wideband, or multiband frequency range. The antireflection can be dependent or independent of the incident wave polarization. Moreover, antireflection at a very wide incidence angle can be attained. The reflection from a substrate is controlled by a buried nanoantenna array, a structure composed of (1) a subwavelength metallic array and (2) a dielectric cover layer referred to as a superstrate. The material properties and thickness of the superstrate and nanoantennas' geometry and periodicity control the phase and intensity of the wave circulating inside the superstrate cavity. A minimum reflectance of 0.02% is achieved in various experiments in the mid-infrared from a silicon substrate. The design can be integrated in straightforward way in optical devices. The proposed structure is a versatile AR coating to optically impedance matches any substrate to free space in selected any narrow and broadband spectral response across the entire visible and infrared spectrum. PMID:24266700

  4. Versatile SERS sensing based on black silicon.

    PubMed

    Seniutinas, Gediminas; Gervinskas, Gediminas; Verma, Roli; Gupta, Banshi D; Lapierre, Florian; Stoddart, Paul R; Clark, Felix; McArthur, Sally L; Juodkazis, Saulius

    2015-03-01

    Black Si (b-Si) with gold or silver metal coating has been shown to be an extremely effective substrate for surface-enhanced Raman scattering (SERS). Here, we demonstrate that it is also a highly versatile SERS platform, as it supports a wide range of surface functionalizations. In particular, we report the use of a molecularly imprinted polymer (MIP) coating and a hydrophobic coating on b-Si to establish two different sensing modalities. First, using a MIP layer on Au-coated b-Si, we show selective sensing of two closely related varieties of tetracycline. Second, a hydrophobic coating was used to concentrate the analyte adsorbed on gold colloidal nanoparticles, thus increasing the sensitivity of the measurement by an order of magnitude. In this experiment, Au nanoparticles and analyte were mixed just before SERS measurements and were concentrated by drop-drying on the super-hydrophobic b-Si. These approaches are promising for SERS measurements that are sensitive to the aging of bare plasmonic metal-coated substrates. PMID:25836894

  5. Type IV Pilin Proteins: Versatile Molecular Modules

    PubMed Central

    Giltner, Carmen L.; Nguyen, Ylan

    2012-01-01

    Summary: Type IV pili (T4P) are multifunctional protein fibers produced on the surfaces of a wide variety of bacteria and archaea. The major subunit of T4P is the type IV pilin, and structurally related proteins are found as components of the type II secretion (T2S) system, where they are called pseudopilins; of DNA uptake/competence systems in both Gram-negative and Gram-positive species; and of flagella, pili, and sugar-binding systems in the archaea. This broad distribution of a single protein family implies both a common evolutionary origin and a highly adaptable functional plan. The type IV pilin is a remarkably versatile architectural module that has been adopted widely for a variety of functions, including motility, attachment to chemically diverse surfaces, electrical conductance, acquisition of DNA, and secretion of a broad range of structurally distinct protein substrates. In this review, we consider recent advances in this research area, from structural revelations to insights into diversity, posttranslational modifications, regulation, and function. PMID:23204365

  6. Plasmonic Biofoam: A Versatile Optically Active Material.

    PubMed

    Tian, Limei; Luan, Jingyi; Liu, Keng-Ku; Jiang, Qisheng; Tadepalli, Sirimuvva; Gupta, Maneesh K; Naik, Rajesh R; Singamaneni, Srikanth

    2016-01-13

    Owing to their ability to confine and manipulate light at the nanoscale, plasmonic nanostructures are highly attractive for a broad range of applications. While tremendous progress has been made in the synthesis of size- and shape-controlled plasmonic nanostructures, their integration with other materials and application in solid-state is primarily through their assembly on rigid two-dimensional (2D) substrates, which limits the plasmonically active space to a few nanometers above the substrate. In this work, we demonstrate a simple method to create plasmonically active three-dimensional biofoams by integrating plasmonic nanostructures with highly porous biomaterial aerogels. We demonstrate that plasmonic biofoam is a versatile optically active platform that can be harnessed for numerous applications including (i) ultrasensitive chemical detection using surface-enhanced Raman scattering; (ii) highly efficient energy harvesting and steam generation through plasmonic photothermal heating; and (iii) optical control of enzymatic activity by triggered release of biomolecules encapsulated within the aerogel. Our results demonstrate that 3D plasmonic biofoam exhibits significantly higher sensing, photothermal, and loading efficiency compared to conventional 2D counterparts. The design principles and processing methodology of plasmonic aerogels demonstrated here can be broadly applied in the fabrication of other functional foams. PMID:26630376

  7. Development of versatile multiaperture negative ion sources

    SciTech Connect

    Cavenago, M.; Minarello, A.; Sattin, M.; Serianni, G.; Antoni, V.; Bigi, M.; Pasqualotto, R.; Recchia, M.; Veltri, P.; Agostinetti, P.; Barbisan, M.; Baseggio, L.; Cervaro, V.; Degli Agostini, F.; Franchin, L.; Laterza, B.; Ravarotto, D.; Rossetto, F.; Zaniol, B.; Zucchetti, S.; and others

    2015-04-08

    Enhancement of negative ion sources for production of large ion beams is a very active research field nowadays, driven from demand of plasma heating in nuclear fusion devices and accelerator applications. As a versatile test bench, the ion source NIO1 (Negative Ion Optimization 1) is being commissioned by Consorzio RFX and INFN. The nominal beam current of 135 mA at −60 kV is divided into 9 beamlets, with multiaperture extraction electrodes. The plasma is sustained by a 2 MHz radiofrequency power supply, with a standard matching box. A High Voltage Deck (HVD) placed inside the lead shielding surrounding NIO1 contains the radiofrequency generator, the gas control, electronics and power supplies for the ion source. An autonomous closed circuit water cooling system was installed for the whole system, with a branch towards the HVD, using carefully optimized helical tubing. Insulation transformer is installed in a nearby box. Tests of several magnetic configurations can be performed. Status of experiments, measured spectra and plasma luminosity are described. Upgrades of magnetic filter, beam calorimeter and extraction grid and related theoretical issues are reviewed.

  8. Development of versatile multiaperture negative ion sources

    NASA Astrophysics Data System (ADS)

    Cavenago, M.; Serianni, G.; Antoni, V.; Bigi, M.; De Muri, M.; Pasqualotto, R.; Recchia, M.; Veltri, P.; Agostinetti, P.; Barbisan, M.; Baseggio, L.; Cervaro, V.; Cazzador, M.; Degli Agostini, F.; Franchin, L.; Kulevoy, T.; Laterza, B.; Mimo, A.; Minarello, A.; Petrenko, S.; Ravarotto, D.; Rossetto, F.; Sattin, M.; Zaniol, B.; Zucchetti, S.

    2015-04-01

    Enhancement of negative ion sources for production of large ion beams is a very active research field nowadays, driven from demand of plasma heating in nuclear fusion devices and accelerator applications. As a versatile test bench, the ion source NIO1 (Negative Ion Optimization 1) is being commissioned by Consorzio RFX and INFN. The nominal beam current of 135 mA at -60 kV is divided into 9 beamlets, with multiaperture extraction electrodes. The plasma is sustained by a 2 MHz radiofrequency power supply, with a standard matching box. A High Voltage Deck (HVD) placed inside the lead shielding surrounding NIO1 contains the radiofrequency generator, the gas control, electronics and power supplies for the ion source. An autonomous closed circuit water cooling system was installed for the whole system, with a branch towards the HVD, using carefully optimized helical tubing. Insulation transformer is installed in a nearby box. Tests of several magnetic configurations can be performed. Status of experiments, measured spectra and plasma luminosity are described. Upgrades of magnetic filter, beam calorimeter and extraction grid and related theoretical issues are reviewed.

  9. The Cilium Secretes Bioactive Ectosomes

    PubMed Central

    Wood, CR; Huang, K; Diener, DR; Rosenbaum, JL

    2013-01-01

    Summary The release of membrane vesicles from the surface of cells into their surrounding environment is now recognized as an important pathway for the delivery of proteins to extracellular sites of biological function. Membrane vesicles of this kind, termed exosomes and ectosomes, are the result of active processes and have been shown to carry a wide array of biological effector molecules that can play roles in cell-to-cell communication and remodeling of the extracellular space [17]. Degradation of the extracellular matrix (ECM) through the regulated release of proteolytic enzymes is a key process for development, morphogenesis and cell migration in animal and plant cells. Here we show that the unicellular alga, Chlamydomonas, achieves the timely degradation of its mother cell wall, a type of ECM, through the budding of ectosomes directly from the membranes of their flagella. Using a combination of immunoelectron microscopy, immunofluorescence microscopy, and functional analysis, we demonstrate that these vesicles, which we term ciliary ectosomes, act as carriers of the proteolytic enzyme necessary for the liberation of daughter cells following mitosis [8, 9]. Chlamydomonas has proven to be the key unicellular model for the highly conserved mechanisms of mammalian cilia, and our results suggest that cilia may be an under-appreciated source of bioactive, extracellular membrane vesicles. PMID:23623554

  10. Bioactive compounds from marine actinomycetes.

    PubMed

    Solanki, Renu; Khanna, Monisha; Lal, Rup

    2008-12-01

    Actinomycetes are one of the most efficient groups of secondary metabolite producers and are very important from an industrial point of view. Among its various genera, Streptomyces, Saccharopolyspora, Amycolatopsis, Micromonospora and Actinoplanes are the major producers of commercially important biomolecules. Several species have been isolated and screened from the soil in the past decades. Consequently the chance of isolating a novel actinomycete strain from a terrestrial habitat, which would produce new biologically active metabolites, has reduced. The most relevant reason for discovering novel secondary metabolites is to circumvent the problem of resistant pathogens, which are no longer susceptible to the currently used drugs. Existence of actinomycetes has been reported in the hitherto untapped marine ecosystem. Marine actinomycetes are efficient producers of new secondary metabolites that show a range of biological activities including antibacterial, antifungal, anticancer, insecticidal and enzyme inhibition. Bioactive compounds from marine actinomycetes possess distinct chemical structures that may form the basis for synthesis of new drugs that could be used to combat resistant pathogens. PMID:23100742

  11. Bioactive Constituents of Indigofera spicata

    PubMed Central

    Prez, Lynette Bueno; Li, Jie; Lantvit, Daniel D.; Pan, Li; Ninh, Tran Ngoc; Chai, Hee-Byung; Soejarto, Djaja Djendoel; Swanson, Steven M.; Lucas, David M.; Kinghorn, A. Douglas

    2013-01-01

    Four new flavanones, designated as (+)?5?-deacetylpurpurin (1), (+)?5-methoxypurpurin (2), (2S)-2,3-dihydrotephroglabrin (3), and (2S)-2,3-dihydrotephroapollin C (4), together with two known flavanones (5 and 6), three known rotenoids (79), and one known chalcone (10) were isolated from a chloroform-soluble partition of a methanol extract from the combined flowers, fruits, leaves, and twigs of Indigofera spicata, collected in Vietnam. The compounds were obtained by bioactivity-guided isolation using HT-29 human colon cancer, 697 human acute lymphoblastic leukemia, and Raji human Burkitts lymphoma cell lines. The structures of 14 were established by extensive 1D- and 2D-NMR experiments and the absolute configurations were determined by the measurement of specific rotations and CD spectra. The cytotoxic activities of the isolated compounds were tested against the HT-29, 697, Raji and the CCD-112CoN human normal colon cells. Also, the quinone reductase induction activities of the isolates were determined using the Hepa 1c1c7 murine hepatoma cell line. In addition, cis-6a??12a?-hydroxyrotenone (7) was evaluated in an in vivo hollow fiber bioassay using HT-29, MCF-7 human breast cancer, and MDA-MB-435 human melanoma cells. PMID:23895019

  12. [Development and research advances of iridoids from Valeriana jatamansi and their bioactivity].

    PubMed

    Zhang, Ning-ning; Ding, Guang-zhi

    2015-05-01

    Valeriana jatamansi (syn. V. wallichii), a traditional Chinese medicine recorded in Chinese Pharmacopeia (1977 and 2010 edition), has been used for treatment of a variety of conditions including sleep problems, obesity, nervous disorders, epilepsy, insanity, snake poisoning, eye trouble, and skin diseases. Also, it was used as an important substitute for the European V. officinalis, whose root preparation, popularly known as valerian, has been employed as a mild sedative for a long time. In recent years, much attention has been draw to the iridoids, one of the major bioactive constituents of V. jatamansi, leading to the discovery of a series of new iridoids with anti-tumor and neuroprotective activities. Their action machnism also has been discussed. This paper summerized the iridoids and their bioactivities from V. jatamansi in recent years, which could provide basic foundation for development and research of V. jatamansi. PMID:26390643

  13. Bioactive cotton fabrics containing chitosan and biologically active substances extracted from plants.

    PubMed

    Mocanu, G; Nichifor, M; Mihai, D; Oproiu, L C

    2013-01-01

    The paper studies the obtaining of bioactive textiles using chitosan-coated fabrics, in which biologically active substances contained by Viola Tricolor (VT) - an extract of three Viola species (Violaceae) - were immobilized. Chitosan was applied on cotton fabric or on chemically modified cotton (having reactive -CHO or carboxymethyl groups), as tripolyphosphate (TPP) crosslinked fine particles, or by use of glutaraldehyde crosslinking agent. The amount of VT retained on the fabrics was found to depend on the procedure of chitosan application on the cotton. The obtained bioactive textiles are expected to have antioxidant activity due to the biologically active substances from VT; they can be used for obtaining clothes for people with allergies or other skin problems, assuring a controlled release of biomolecules. The study focuses on the in vitro release of VT retained on the fabrics, as well as on its antioxidant activity. PMID:25428045

  14. Development of bioactive and biodegradable chitosan-based injectable systems containing bioactive glass nanoparticles.

    PubMed

    Couto, Daniela S; Hong, Zhongkui; Mano, João F

    2009-01-01

    There is increasing interest in the development of new tissue engineering strategies to deliver cells and bioactive agents encapsulated in a biodegradable matrix through minimally invasive procedures. The present work proposes to combine chitosan-beta-glycerophosphate salt formulations with bioactive glass nanoparticles in order to conceive novel injectable thermo-responsive hydrogels for orthopaedic reconstructive and regenerative medicine applications. The initial rheological properties and the gelation points of the developed organic-inorganic in situ thermosetting systems were revealed to be adequate for intracorporal injection. In vitro bioactivity tests, using incubation protocols in simulated body fluid (SBF), allowed the observation of bone-like apatite formation in the hydrogel formulations containing bioactive nanoparticles. The density of the apatite formed increased with increasing bioactive glass content and soaking time in SBF. These results indicate that the stimuli-responsive hydrogels could potentially be used as temporary injectable scaffolds in bone tissue engineering applications. PMID:18835230

  15. Metadata Authoring with Versatility and Extensibility

    NASA Technical Reports Server (NTRS)

    Pollack, Janine; Olsen, Lola

    2004-01-01

    NASA's Global Change Master Directory (GCMD) assists the scientific community in the discovery of and linkage to Earth science data sets and related services. The GCMD holds over 13,800 data set descriptions in Directory Interchange Format (DIF) and 700 data service descriptions in Service Entry Resource Format (SERF), encompassing the disciplines of geology, hydrology, oceanography, meteorology, and ecology. Data descriptions also contain geographic coverage information and direct links to the data, thus allowing researchers to discover data pertaining to a geographic location of interest, then quickly acquire those data. The GCMD strives to be the preferred data locator for world-wide directory-level metadata. In this vein, scientists and data providers must have access to intuitive and efficient metadata authoring tools. Existing GCMD tools are attracting widespread usage; however, a need for tools that are portable, customizable and versatile still exists. With tool usage directly influencing metadata population, it has become apparent that new tools are needed to fill these voids. As a result, the GCMD has released a new authoring tool allowing for both web-based and stand-alone authoring of descriptions. Furthermore, this tool incorporates the ability to plug-and-play the metadata format of choice, offering users options of DIF, SERF, FGDC, ISO or any other defined standard. Allowing data holders to work with their preferred format, as well as an option of a stand-alone application or web-based environment, docBUlLDER will assist the scientific community in efficiently creating quality data and services metadata.

  16. The neural crest: a versatile organ system.

    PubMed

    Zhang, Dongcheng; Ighaniyan, Samiramis; Stathopoulos, Lefteris; Rollo, Benjamin; Landman, Kerry; Hutson, John; Newgreen, Donald

    2014-09-01

    The neural crest is the name given to the strip of cells at the junction between neural and epidermal ectoderm in neurula-stage vertebrate embryos, which is later brought to the dorsal neural tube as the neural folds elevate. The neural crest is a heterogeneous and multipotent progenitor cell population whose cells undergo EMT then extensively and accurately migrate throughout the embryo. Neural crest cells contribute to nearly every organ system in the body, with derivatives of neuronal, glial, neuroendocrine, pigment, and also mesodermal lineages. This breadth of developmental capacity has led to the neural crest being termed the fourth germ layer. The neural crest has occupied a prominent place in developmental biology, due to its exaggerated migratory morphogenesis and its remarkably wide developmental potential. As such, neural crest cells have become an attractive model for developmental biologists for studying these processes. Problems in neural crest development cause a number of human syndromes and birth defects known collectively as neurocristopathies; these include Treacher Collins syndrome, Hirschsprung disease, and 22q11.2 deletion syndromes. Tumors in the neural crest lineage are also of clinical importance, including the aggressive melanoma and neuroblastoma types. These clinical aspects have drawn attention to the selection or creation of neural crest progenitor cells, particularly of human origin, for studying pathologies of the neural crest at the cellular level, and also for possible cell therapeutics. The versatility of the neural crest lends itself to interlinked research, spanning basic developmental biology, birth defect research, oncology, and stem/progenitor cell biology and therapy. PMID:25227568

  17. A Versatile Family of Galactic Wind Models

    NASA Astrophysics Data System (ADS)

    Bustard, Chad; Zweibel, Ellen G.; D’Onghia, Elena

    2016-03-01

    We present a versatile family of model galactic outflows including non-uniform mass and energy source distributions, a gravitational potential from an extended mass source, and radiative losses. The model easily produces steady-state wind solutions for a range of mass-loading factors, energy-loading factors, galaxy mass, and galaxy radius. We find that, with radiative losses included, highly mass-loaded winds must be driven at high central temperatures, whereas low mass-loaded winds can be driven at low temperatures just above the peak of the cooling curve, meaning radiative losses can drastically affect the wind solution even for low mass-loading factors. By including radiative losses, we are able to show that subsonic flows can be ignored as a possible mechanism for expelling mass and energy from a galaxy compared to the more efficient transonic solutions. Specifically, the transonic solutions with low mass loading and high energy loading are the most efficient. Our model also produces low-temperature, high-velocity winds that could explain the prevalence of low-temperature material in observed outflows. Finally, we show that our model, unlike the well-known Chevalier & Clegg model, can reproduce the observed linear relationship between wind X-ray luminosity and star formation rate (SFR) over a large range of SFR from 1–1000 M⊙ yr‑1 assuming the wind mass-loading factor is higher for low-mass, and hence, low-SFR galaxies. We also constrain the allowed mass-loading factors that can fit the observed X-ray luminosity versus SFR trend, further suggesting an inverse relationship between mass loading and SFR as explored in advanced numerical simulations.

  18. Viral Skin Diseases.

    PubMed

    Ramdass, Priya; Mullick, Sahil; Farber, Harold F

    2015-12-01

    In the vast world of skin diseases, viral skin disorders account for a significant percentage. Most viral skin diseases present with an exanthem (skin rash) and, oftentimes, an accompanying enanthem (lesions involving the mucosal membrane). In this article, the various viral skin diseases are explored, including viral childhood exanthems (measles, rubella, erythema infectiosum, and roseola), herpes viruses (herpes simplex virus, varicella zoster virus, Kaposi sarcoma herpes virus, viral zoonotic infections [orf, monkeypox, ebola, smallpox]), and several other viral skin diseases, such as human papilloma virus, hand, foot, and mouth disease, molluscum contagiosum, and Gianotti-Crosti syndrome. PMID:26612372

  19. Silk sericin: A versatile material for tissue engineering and drug delivery.

    PubMed

    Lamboni, Lallepak; Gauthier, Mario; Yang, Guang; Wang, Qun

    2015-12-01

    Sericin is an inexpensive glycoprotein obtained as a by-product in the silk industry. Its variable amino acid composition and diverse functional groups confer upon it attractive bioactive properties, which are particularly interesting for biomedical applications. Because of its antioxidant character, moisturizing ability, and mitogenic effect on mammalian cells, sericin is useful in cell culture and tissue engineering. Its positive effects on keratinocytes and fibroblasts have led to the development of sericin-based biomaterials for skin tissue repair, mainly as wound dressings. Additionally, sericin can be used for bone tissue engineering owing to its ability to induce nucleation of bone-like hydroxyapatite. Stable silk sericin biomaterials, such as films, sponges, and hydrogels, are prepared by cross-linking, ethanol precipitation, or blending with other polymers. Sericin may also be employed for drug delivery because its chemical reactivity and pH-responsiveness facilitate the fabrication of nano- and microparticles, hydrogels, and conjugated molecules, improving the bioactivity of drugs. Here, we summarized the recent advancements in the study of silk sericin for application in tissue engineering and drug delivery. PMID:26523781

  20. Simple bioconjugate chemistry serves great clinical advances: albumin as a versatile platform for diagnosis and precision therapy.

    PubMed

    Liu, Zhibo; Chen, Xiaoyuan

    2016-02-29

    Albumin is the most abundant circulating protein in plasma and has recently emerged as a versatile protein carrier for drug targeting and for improving the pharmacokinetic profile of peptide or protein based drugs. Three drug delivery technologies related to albumin have been developed, which include the coupling of low-molecular weight drugs to exogenous or endogenous albumin, conjugating bioactive proteins by albumin fusion technology (AFT), and encapsulation of drugs into albumin nanoparticles. This review article starts with a brief introduction of human serum albumin (HSA), and then summarizes the mainstream chemical strategies of developing HSA binding molecules for coupling with drug molecules. Moreover, we also concisely condense the recent progress of the most important clinical applications of HSA-binding platforms, and specify the current challenges that need to be met for a bright future of HSA-binding. PMID:26771036

  1. Photodermatoses in pigmented skin.

    PubMed

    Sharma, Vinod Kumar; Sahni, Kanika; Wadhwani, Ashok Roopchand

    2013-01-01

    Photodermatoses are a group of skin diseases primarily caused by, or exacerbated by exposure to ultraviolet and or visible radiation. The effect of sunlight on skin depends on a number of factors including skin colour, skin phototype and the content and type of melanin in the skin. There are only a few studies describing photodermatoses in populations with dark skin. A PubMed search was conducted to summarize currently available information on differences in biology of melanin in dark and light skin and photodermatoses in dark skin. Dark skin is characterised by higher content of melanin, higher eumelanin to pheomelanin ratio, lower tyrosinase activity, and more effective distribution of melanin for protection against ultraviolet light. Photodermatoses are common in dark skinned patients with some variation in the spectrum of photodermatoses. Polymorphous light eruption (PMLE) is the commonest, followed by chronic actinic dermatitis. Pin-point papular and lichenoid variants of PMLE and actinic lichen planus are more frequent in dark skin whereas actinic prurigo, solar urticaria and hydroa vacciniforme are uncommon. Photodermatoses are common in dark skinned patients despite better natural photoprotection. It is proposed that lichenoid photodermatoses may be added to the classification of photodermatoses in dark skin. PMID:23123922

  2. A versatile hardware platform for brain computer interfaces.

    PubMed

    Garcia, Pablo A; Haberman, Marcelo; Spinelli, Enrique M

    2010-01-01

    This article presents the development of a versatile hardware platform for brain computer interfaces (BCI). The aim of this work is to produce a small, autonomous and configurable BCI platform adaptable to the user's needs. PMID:21096891

  3. Composite surgical sutures with bioactive glass coating.

    PubMed

    Boccaccini, Aldo R; Stamboulis, Artemis G; Rashid, Azrina; Roether, Judith A

    2003-10-15

    A processing method was developed to coat polyglactin 910 (Vicryl) sutures with bioactive glass powder (45S5 Bioglass). High reproducibility and homogeneity of the coating in terms of microstructure and thickness along the suture length were achieved. Bioglass-coated sutures exhibited a high level of chemical reactivity in simulated body fluid (SBF), indicating their bioactive behavior. This was evident by the prompt formation of hydroxyapatite (HA) crystals on the surface after only 7 days of immersion in SBF. These crystals grew to form a thick HA layer (15 microm thickness) after 3 weeks in SBF. The tensile strength of the sutures was tested before and after immersion in SBF in order to assess the effect of the bioactive glass coating on suture degradation. The tensile strength of composite sutures was lower than that of as-received Vicryl sutures, 385 and 467 MPa, respectively. However, after 28 days of immersion in SBF the residual tensile strengths of coated and uncoated sutures were similar (83 and 88 MPa, respectively), indicating no negative effect of the HA layer formation on the suture strength. The effect of bioactive glass coating on the polymer degradation is discussed. The developed bioactive sutures represent interesting materials for applications in wound healing, fabrication of fibrous three-dimensional scaffolds for tissue engineering, and reinforcement elements for calcium-phosphate temporary implants. PMID:14528459

  4. Microencapsulation of bioactives for food applications.

    PubMed

    Dias, Maria Ins; Ferreira, Isabel C F R; Barreiro, Maria Filomena

    2015-04-01

    Health issues are an emerging concern to the world population, and therefore the food industry is searching for novel food products containing health-promoting bioactive compounds, with little or no synthetic ingredients. However, there are some challenges in the development of functional foods, particularly in which the direct use of some bioactives is involved. They can show problems of instability, react with other food matrix ingredients or present strong odour and/or flavours. In this context, microencapsulation emerges as a potential approach to overcome these problems and, additionally, to provide controlled or targeted delivery or release. This work intends to contribute to the field of functional food development by performing a comprehensive review on the microencapsulation methods and materials, the bioactives used (extracts and isolated compounds) and the final application development. Although several studies dealing with microencapsulation of bioactives exist, they are mainly focused on the process development and the majority lack proof of concept for final applications. These factors, together with the lack of regulation, in Europe and in the United States, delay the development of new functional foods and, consequently, their market entry. In conclusion, the potential of microencapsulation to protect bioactive compounds ensuring their bioavailability is shown, but further studies are required, considering both its applicability and incentives by regulatory agencies. PMID:25710906

  5. Increased levels of palmitoylethanolamide and other bioactive lipid mediators and enhanced local mast cell proliferation in canine atopic dermatitis

    PubMed Central

    2014-01-01

    Background Despite the precise pathogenesis of atopic dermatitis (AD) is unknown, an immune dysregulation that causes Th2-predominant inflammation and an intrinsic defect in skin barrier function are currently the two major hypotheses, according to the so-called outside-inside-outside model. Mast cells (MCs) are involved in AD both by releasing Th2 polarizing cytokines and generating pruritus symptoms through release of histamine and tryptase. A link between MCs and skin barrier defects was recently uncovered, with histamine being found to profoundly contribute to the skin barrier defects. Palmitoylethanolamide and related lipid mediators are endogenous bioactive compounds, considered to play a protective homeostatic role in many tissues: evidence collected so far shows that the anti-inflammatory effect of palmitoylethanolamide depends on the down-modulation of MC degranulation. Based on this background, the purpose of the present study was twofold: (a) to determine if the endogenous levels of palmitoylethanolamide and other bioactive lipid mediators are changed in the skin of AD dogs compared to healthy animals; (b) to examine if MC number is increased in the skin of AD dogs and, if so, whether it depends on MC in-situ proliferation. Results The amount of lipid extract expressed as percent of biopsy tissue weight was significantly reduced in AD skin while the levels of all analyzed bioactive lipid mediators were significantly elevated, with palmitoylethanolamide showing the highest increase. In dogs with AD, the number of MCs was significantly increased in both the subepidermal and the perifollicular compartments and their granule content was significantly decreased in the latter. Also, in situ proliferation of MCs was documented. Conclusions The levels of palmitoylethanolamide and other bioactive lipid mediators were shown to increase in AD skin compared to healthy samples, leading to the hypothesis that they may be part of the body’s innate mechanisms to maintain cellular homeostasis when faced with AD-related inflammation. In particular, the increase may be considered a temptative response to down-regulating the observed elevation in the number, functionality and proliferative state of MCs in the skin of AD dogs. Further studies are warranted to confirm the hypothesis. PMID:24423192

  6. Layers of the Skin

    MedlinePLUS

    ... deeper layers of the skin from the harmful effects of the sun. Sun exposure causes melanocytes to increase production of melanin in order to protect the skin from damaging ultraviolet rays, producing a suntan. Patches of melanin in the ...

  7. Skin Cancer Foundation

    MedlinePLUS

    ... Actinic Keratosis Basal Cell Carcinoma Dysplastic Nevi Melanoma Squamous Cell Carcinoma Skin Cancer Treatment Glossary Facts & Statistics Ask the ... Actinic Keratosis Basal Cell Carcinoma Dysplastic Nevi Melanoma Squamous Cell Carcinoma Skin Cancer Treatment Glossary Facts & Statistics Early Detection ...

  8. Skin Pigmentation Disorders

    MedlinePLUS

    ... skin gets its color from a pigment called melanin. Special cells in the skin make melanin. When these cells become damaged or unhealthy, it affects melanin production. Some pigmentation disorders affect just patches of ...

  9. Skin Complications of IBD

    MedlinePLUS

    ... chronic illnesses such as IBD. PYODERMA VEGETANS and VASCULITIS are other rare skin disorders, believed to be ... become darkened areas of skin as they heal. Vasculitis, which means “inflammation of the blood vessels,” is ...

  10. Tuberculin skin test (image)

    MedlinePLUS

    ... evaluate whether a person has been exposed to tuberculosis. If there has been a prior exposure, antibodies ... in the body. During the skin test, the tuberculosis antigen is injected under the skin and if ...

  11. Polymer photonic sensing skin

    NASA Astrophysics Data System (ADS)

    Chen, X.; Zhang, C.; Webb, D. J.; Van Hoe, B.; Van Steenberge, G.; Kalli, K.; Berghmans, F.; Thienpont, H.; Urbanczyk, W.; Sugden, K.; Peng, G.-D.

    2010-09-01

    A highly flexible sensing skin with embedded polymer optical fibre Bragg gratings is characterised The response to pressure and strain compare favourably to a similar skin instrumented with silica fibre Bragg grating sensors.

  12. Squamous cell skin cancer

    MedlinePLUS

    ... occur on skin that is regularly exposed to sunlight or other ultraviolet radiation. The earliest form of ... skin cancer is to reduce your exposure to sunlight . Always use sunscreen: Apply sunscreen with sun protection ...

  13. Tissue viability imaging for quantification of skin erythema and blanching

    NASA Astrophysics Data System (ADS)

    Nilsson, Gert E.; Leahy, Martin J.

    2010-02-01

    Naked eye observation has up to recently been the main method of determining skin erythema (vasodilatation) and blanching (vasoconstriction) in skin testing. Since naked eye observation is a highly subjective and investigatordependent method, it is difficult to attain reproducibility and to compare results reported by different researchers performing their studies at different laboratories. Consequently there is a need for more objective, quantitative and versatile methods in the assessment of alterations in skin erythema and blanching caused by internal and external factors such as the intake of vasoactive drugs, application of agents on the skin surface and by constituents in the environment. Since skin microcirculation is sensitive to applied pressure and heat, such methods should preferably be noninvasive and designed for remote use without touching the skin. As skin microcirculation further possesses substantial spatial variability, imaging techniques are to be preferred before single point measurements. An emerging technology based on polarization digital camera spectroscopy - Tissue Viability Imaging (TiVi) - fulfills these requirements. The principles of TiVi (1) and some of its early applications (2-5) are addressed in this paper.

  14. Biology of Skin Color.

    ERIC Educational Resources Information Center

    Corcos, Alain

    1983-01-01

    Information from scientific journals on the biology of skin color is discussed. Major areas addressed include: (1) biology of melanin, melanocytes, and melanosomes; (2) melanosome and human diversity; (3) genetics of skin color; and (4) skin color, geography, and natural selection. (JN)

  15. Bioactive Proteins and Peptides from Soybeans.

    PubMed

    Agyei, Dominic

    2015-01-01

    Dietary proteins from soybeans have been shown to offer health benefits in vivo and/or in vitro either as intact proteins or in partially digested forms also called bioactive peptides. Upon oral administration and absorption, soy-derived bioactive peptides may induce several physiological responses such as antioxidative, antimicrobial, antihypertensive, anticancer and immunomodulatory effects. There has therefore been a mounting research interest in the therapeutic potential of soy protein hydrolysates and their subsequent incorporation in functional foods and 'Food for Specified Health Uses' (FOSHU) related products where their biological activities may assist in the promotion of good health or in the control and prevention of diseases. This mini review discusses relevant patents and gives an overview on bioactive proteins and peptides obtainable from soybeans. Processes for the production and formulation of these peptides are given, together with specific examples of their therapeutic potential and possible areas of application. PMID:26118541

  16. [Review of bioactivities of natural cycloartane triterpenoids].

    PubMed

    Tian, Ze; Xiao, Pei-gen; Wen, Jie; Huang, Feng; Yang, Meng-su; Chen, Shi-lin

    2006-04-01

    Cycloartane triterpenoids, which exist widely in nature, are mainly distributed in Astragalus (Leguminosae) species, Trib. Cimicifuga (Ranunculaceae) and Thalictrium (Ranunculaceae) species and possess various bioactivities. Along with the development of isolation techniques of phytochemistry, more and more this kind of compounds are isolated and identified. However, bioactivity researches on the compounds are relatively lagged behind. Most researches are still in screening level, deficient in mechanism elucidation, short of action proven in vivo and SAR analysis. The author summarized the bioactivity of this kind of compounds from all aspects: anti-tumor, anti-virus, antibacterial, anti-inflammation, immune-regulatory, cardiovascular system, hepatic protection and so forth. This will be benefit for the further research and development of the compounds. PMID:16830816

  17. Microbial biotransformation of bioactive flavonoids.

    PubMed

    Cao, Hui; Chen, Xiaoqing; Jassbi, Amir Reza; Xiao, Jianbo

    2015-01-01

    The bioactive flavonoids are considered as the most important phytochemicals in food, which exert a wide range of biological benefits for human being. Microbial biotransformation strategies for production of flavonoids have attracted considerable interest because they allow yielding novel flavonoids, which do not exist in nature. In this review, we summarize the existing knowledge on the production and biotransformation of flavonoids by various microbes. The main reactions during microbial biotransformation are hydroxylation, dehydroxylation, O-methylation, O-demethylation, glycosylation, deglycosylation, dehydrogenation, hydrogenation, C ring cleavage of the benzo-?-pyrone system, cyclization, and carbonyl reduction. Cunninghamella, Penicillium, and Aspergillus strains are very popular to biotransform flavonoids and they can perform almost all the reactions with excellent yields. Aspergillus niger is one of the most applied microorganisms in the flavonoids' biotransformation; for example, A. niger can transfer flavanone to flavan-4-ol, 2'-hydroxydihydrochalcone, flavone, 3-hydroxyflavone, 6-hydroxyflavanone, and 4'-hydroxyflavanone. The hydroxylation of flavones by microbes usually happens on the ortho position of hydroxyl group on the A ring and C-4' position of the B ring and microbes commonly hydroxylate flavonols at the C-8 position. The microorganisms tend to hydroxylate flavanones at the C-5, 6, and 4' positions; however, for prenylated flavanones, dihydroxylation often takes place on the C4?=C5? double bond on the prenyl group (the side chain of A ring). Isoflavones are usually hydroxylated at the C-3' position of the B ring by microorganisms. The microbes convert flavonoids to their 7-O-glycosides and 3-O-glycosides (when flavonoids have a hydroxyl moiety at the C-3 position). The demethylation of multimethoxyl flavonoids by microbes tends to happen at the C-3' and C-4' positions of the B ring. Multimethoxyl flavanones and isoflavone are demethylated at the C-7 and C-4' positions. The O-methylation of flavonols happens at the C-3' and C-4' and microorganisms O-methylate flavones at the C-6 position and the O-methylation of flavanones, usually took place on the hydroxyl groups of the A ring. The prenyl flavanones were cyclized at the prenyl side chain to form a new five-member ring attached to the A ring. Chalcones were regioselectively cyclized to flavanones. Hydrogenation of flavonoids was only reported on transformation of chalcones to dihydrochalcones. The dehydrogenation of flavanoids to flavonoids was not comprehensively studied. PMID:25447420

  18. Bioactive proteins and peptides in foods.

    PubMed

    Walther, Barbara; Sieber, Robert

    2011-03-01

    Increasing amounts of data demonstrate a bioactive role of proteins and peptides above and beyond their nutritional impact. The focus of the investigations has mainly been on vitamin- and mineral-binding proteins, on antimicrobial, immunosuppressing/-modulatory proteins, and on proteins with enzyme inhibitory activity as well as on hormones and growth factors from different food proteins; most research has been performed on milk proteins. Because of their molecular size, intact absorption of proteins in the human gastrointestinal tract is limited. Therefore, most of the proteins with biological functions show physiological activity in the gastrointestinal tract by enhancing nutrient absorption, inhibiting enzymes, and modulating the immune system to defend against pathogens. Peptides are released during fermentation or digestion from food proteins by proteolytic enzymes; such peptides have been found mainly in milk. Some of these released peptides exert biological activities such as opiate-like, antihypertensive, mineral-binding, antioxidative, antimicrobial, immuno-, and cytomodulating activity. Intact absorption of these smaller peptides is more likely than that of the larger proteins. Consequently, other organs than the gastrointestinal tract are possible targets for their biological functions. Bioactive proteins as well as bioactive peptides are part of a balanced diet. It is possible to accumulate bioactive peptides in food, for example by using specific microorganisms in fermented dairy products. Although bioactive peptides have been the subject of several studies in vitro and in vivo, their health potential is still under investigation. Up to now, the Commission of European Communities has not (yet) authorized any health claims for bioactive proteins and peptides from food. PMID:22139569

  19. Aeroplysinin-1, a Sponge-Derived Multi-Targeted Bioactive Marine Drug

    PubMed Central

    García-Vilas, Javier A.; Martínez-Poveda, Beatriz; Quesada, Ana R.; Medina, Miguel Ángel

    2015-01-01

    Organisms lacking external defense mechanisms have developed chemical defense strategies, particularly through the production of secondary metabolites with antibiotic or repellent effects. Secondary metabolites from marine organisms have proven to be an exceptionally rich source of small molecules with pharmacological activities potentially beneficial to human health. (+)-Aeroplysinin-1 is a secondary metabolite isolated from marine sponges with a wide spectrum of bio-activities. (+)-Aeroplysinin-1 has potent antibiotic effects on Gram-positive bacteria and several dinoflagellate microalgae causing toxic blooms. In preclinical studies, (+)-aeroplysinin-1 has been shown to have promising anti-inflammatory, anti-angiogenic and anti-tumor effects. Due to its versatility, (+)-aeroplysinin-1 might have a pharmaceutical interest for the treatment of different pathologies. PMID:26703630

  20. Aeroplysinin-1, a Sponge-Derived Multi-Targeted Bioactive Marine Drug.

    PubMed

    Garca-Vilas, Javier A; Martnez-Poveda, Beatriz; Quesada, Ana R; Medina, Miguel ngel

    2015-01-01

    Organisms lacking external defense mechanisms have developed chemical defense strategies, particularly through the production of secondary metabolites with antibiotic or repellent effects. Secondary metabolites from marine organisms have proven to be an exceptionally rich source of small molecules with pharmacological activities potentially beneficial to human health. (+)-Aeroplysinin-1 is a secondary metabolite isolated from marine sponges with a wide spectrum of bio-activities. (+)-Aeroplysinin-1 has potent antibiotic effects on Gram-positive bacteria and several dinoflagellate microalgae causing toxic blooms. In preclinical studies, (+)-aeroplysinin-1 has been shown to have promising anti-inflammatory, anti-angiogenic and anti-tumor effects. Due to its versatility, (+)-aeroplysinin-1 might have a pharmaceutical interest for the treatment of different pathologies. PMID:26703630

  1. Anyone Can Get Skin Cancer

    Cancer.gov

    No matter if your skin is light, dark, or somewhere in between, everyone is at risk for skin cancer. Learn what skin cancer looks like, how to find it early, and how to lower the chance of skin cancer.

  2. Skin, Reactive Oxygen Species, and Circadian Clocks

    PubMed Central

    Ndiaye, Mary A.; Nihal, Minakshi; Wood, Gary S.

    2014-01-01

    Abstract Significance: Skin, a complex organ and the body's first line of defense against environmental insults, plays a critical role in maintaining homeostasis in an organism. This balance is maintained through a complex network of cellular machinery and signaling events, including those regulating oxidative stress and circadian rhythms. These regulatory mechanisms have developed integral systems to protect skin cells and to signal to the rest of the body in the event of internal and environmental stresses. Recent Advances: Interestingly, several signaling pathways and many bioactive molecules have been found to be involved and even important in the regulation of oxidative stress and circadian rhythms, especially in the skin. It is becoming increasingly evident that these two regulatory systems may, in fact, be interconnected in the regulation of homeostasis. Important examples of molecules that connect the two systems include serotonin, melatonin, vitamin D, and vitamin A. Critical Issues: Excessive reactive oxygen species and/or dysregulation of antioxidant system and circadian rhythms can cause critical errors in maintaining proper barrier function and skin health, as well as overall homeostasis. Unfortunately, the modern lifestyle seems to contribute to increasing alterations in redox balance and circadian rhythms, thereby posing a critical problem for normal functioning of the living system. Future Directions: Since the oxidative stress and circadian rhythm systems seem to have areas of overlap, future research needs to be focused on defining the interactions between these two important systems. This may be especially important in the skin where both systems play critical roles in protecting the whole body. Antioxid. Redox Signal. 20, 2982–2996. PMID:24111846

  3. Polydopamine-Based Simple and Versatile Surface Modification of Polymeric Nano Drug Carriers

    PubMed Central

    Park, Joonyoung; Brust, Tarsis F.; Lee, Hong Jae; Lee, Sang Cheon; Watts, Val J.; Yeo, Yoon

    2014-01-01

    The surface of a polymeric nanoparticle (NP) is often functionalized with cell-interactive ligands and/or additional polymeric layers to control NP interaction with cells and proteins. However, such modification is not always straightforward when the surface is not chemically reactive. For this reason, most NP functionalization processes employ reactive linkers or coupling agents or involve pre-functionalization of the polymer, which are complicated and inefficient. Moreover, pre-functionalized polymers can lose the ability to encapsulate and retain a drug if the added ligands change chemical properties of the polymer. To overcome this challenge, we use dopamine polymerization as a way of functionalizing NP surfaces. This method includes brief incubation of the pre-formed NPs in a weak alkaline solution of dopamine, followed by secondary incubation with desired ligands. Using this method, we have functionalized poly(lactic-co-glycolic acid) (PLGA) NPs with three representative surface modifiers: a small molecule (folate), a peptide (Arg-Gly-Asp), and a polymer [poly(carboxybetaine methacrylate)]. We confirmed that the modified NPs showed the expected cellular interactions with no cytotoxicity or residual bioactivity of dopamine. The dopamine polymerization method is a simple and versatile surface modification method, applicable to a variety of NP drug carriers irrespective of their chemical reactivity and the types of ligands. PMID:24628245

  4. Methods of Manufacturing Bioactive Gels from Extracellular Matrix Material

    NASA Technical Reports Server (NTRS)

    Kentner, Kimberly A. (Inventor); Stuart, Katherine A. (Inventor); Janis, Abram D. (Inventor)

    2015-01-01

    The present invention is directed to methods of manufacturing bioactive gels from ECM material, i.e., gels which retain bioactivity, and can serve as scaffolds for preclinical and clinical tissue engineering and regenerative medicine approaches to tissue reconstruction. The manufacturing methods take advantage of a new recognition that bioactive gels from ECM material can be created by digesting particularized ECM material in an alkaline environment and neutralizing to provide bioactive gels.

  5. Methods of Manufacturing Bioactive Gels from Extracellular Matrix Material

    NASA Technical Reports Server (NTRS)

    Kentner, Kimberly A. (Inventor); Stuart, Katherine A. (Inventor); Janis, Abram D. (Inventor)

    2014-01-01

    The present invention is directed to methods of manufacturing bioactive gels from ECM material, i.e., gels which retain bioactivity, and can serve as scaffolds for preclinical and clinical tissue engineering and regenerative medicine approaches to tissue reconstruction. The manufacturing methods take advantage of a new recognition that bioactive gels from ECM material can be created by digesting particularized ECM material in an alkaline environment and neutralizing to provide bioactive gels.

  6. Methods of Manufacturing Bioactive Gels from Extracellular Matrix Material

    NASA Technical Reports Server (NTRS)

    Kentner, Kimberly A. (Inventor); Stuart, Katherine A. (Inventor); Janis, Abram D. (Inventor)

    2016-01-01

    The present invention is directed to methods of manufacturing bioactive gels from ECM material, i.e., gels which retain bioactivity, and can serve as scaffolds for preclinical and clinical tissue engineering and regenerative medicine approaches to tissue reconstruction. The manufacturing methods take advantage of a new recognition that bioactive gels from ECM material can be created by digesting particularized ECM material in an alkaline environment and neutralizing to provide bioactive gels.

  7. Investigation of bioactivity and cell effects of nano-porous sol-gel derived bioactive glass film

    NASA Astrophysics Data System (ADS)

    Ma, Zhijun; Ji, Huijiao; Hu, Xiaomeng; Teng, Yu; Zhao, Guiyun; Mo, Lijuan; Zhao, Xiaoli; Chen, Weibo; Qiu, Jianrong; Zhang, Ming

    2013-11-01

    In orthopedic surgery, bioactive glass film coating is extensively studied to improve the synthetic performance of orthopedic implants. A lot of investigations have confirmed that nano-porous structure in bioactive glasses can remarkably improve their bioactivity. Nevertheless, researches on preparation of nano-porous bioactive glasses in the form of film coating and their cell response activities are scarce. Herein, we report the preparation of nano-porous bioactive glass film on commercial glass slide based on a sol-gel technique, together with the evaluation of its in vitro bioactivity through immersion in simulated body fluid and monitoring the precipitation of apatite-like layer. Cell responses of the samples, including attachment, proliferation and osteogenic differentiation, were also investigated using BMSCS (bone marrow derived mesenchymal stem cells) as a model. The results presented here provide some basic information on structural influence of bioactive glass film on the improvement of bioactivity and cellular effects.

  8. Metabolically Competent Human Skin Models: Activation and Genotoxicity of Benzo[a]pyrene

    PubMed Central

    Henkler, Frank

    2013-01-01

    The polycyclic aromatic hydrocarbon (PAH) benzo[a]pyrene (BP) is metabolized into a complex pattern of BP derivatives, among which the ultimate carcinogen (+)-anti-BP-7,8-diol-9,10-epoxide (BPDE) is formed to certain extents. Skin is frequently in contact with PAHs and data on the metabolic capacity of skin tissue toward these compounds are inconclusive. We compared BP metabolism in excised human skin, commercially available in vitro 3D skin models and primary 2D skin cell cultures, and analyzed the metabolically catalyzed occurrence of seven different BP follow-up products by means of liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). All models investigated were competent to metabolize BP, and the metabolic profiles generated by ex vivo human skin and skin models were remarkably similar. Furthermore, the genotoxicity of BP and its derivatives was monitored in these models via comet assays. In a full-thickness skin, equivalent BP-mediated genotoxic stress was generated via keratinocytes. Cultured primary keratinocytes revealed a level of genotoxicity comparable with that of direct exposure to 50100nM of BPDE. Our data demonstrate that the metabolic capacity of human skin ex vivo, as well as organotypic human 3D skin models toward BP, is sufficient to cause significant genotoxic stress and thus cutaneous bioactivation may potentially contribute to mutations that ultimately lead to skin cancer. PMID:23148024

  9. Bromophenols in Marine Algae and Their Bioactivities

    PubMed Central

    Liu, Ming; Hansen, Poul Erik; Lin, Xiukun

    2011-01-01

    Marine algae contain various bromophenols that have been shown to possess a variety of biological activities, including antioxidant, antimicrobial, anticancer, anti-diabetic, and anti-thrombotic effects. Here, we briefly review the recent progress of these marine algal biomaterials, with respect to structure, bioactivities, and their potential application as pharmaceuticals. PMID:21822416

  10. Marine bioactives and potential application in sports.

    PubMed

    Gammone, Maria Alessandra; Gemello, Eugenio; Riccioni, Graziano; D'Orazio, Nicolantonio

    2014-05-01

    An enriched diet with antioxidants, such as vitamin E, vitamin C, ?-carotene and phenolic compounds, has always been suggested to improve oxidative stress, preventing related diseases. In this respect, marine natural product (MNP), such as COX inhibitors, marine steroids, molecules interfering with factors involved in the modulation of gene expression (such as NF-?B), macrolides, many antioxidant agents, thermogenic substances and even substances that could help the immune system and that result in the protection of cartilage, have been recently gaining attention. The marine world represents a reserve of bioactive ingredients, with considerable potential as functional food. Substances, such as chitin, chitosan, n-3 oils, carotenoids, vitamins, minerals and bioactive peptides, can provide several health benefits, such as the reduction of cardiovascular diseases, anti-inflammatory and anticarcinogenic activities. In addition, new marine bioactive substances with potential anti-inflammatory, antioxidant and thermogenic capacity may provide health benefits and performance improvement, especially in those who practice physical activity, because of their increased free radical and Reacting Oxygen Species (ROS) production during exercise, and, particularly, in athletes. The aim of this review is to examine the potential pharmacological properties and application of many marine bioactive substances in sports. PMID:24796298

  11. Citrus Limonoids: Analysis, Bioactivity, and Biomedical Prospects

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This publication is a review of the chemistry, biochemistry and bioactivity of limonoids occurring in citrus. The review chronologically relates the evolution of research in citrus limonoids beginning with their association with bitterness development in citrus juices. The chemical and biochemical...

  12. Bioactive Terpenes from Marine-Derived Fungi

    PubMed Central

    Elissawy, Ahmed M.; El-Shazly, Mohamed; Ebada, Sherif S.; Singab, AbdelNasser B.; Proksch, Peter

    2015-01-01

    Marine-derived fungi continue to be a prolific source of secondary metabolites showing diverse bioactivities. Terpenoids from marine-derived fungi exhibit wide structural diversity including numerous compounds with pronounced biological activities. In this review, we survey the last five years’ reports on terpenoidal metabolites from marine-derived fungi with particular attention on those showing marked biological activities. PMID:25854644

  13. DEVELOPMENT OF USDA'S DATABASES FOR BIOACTIVE COMPOUNDS

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The Nutrient Data Laboratory (NDL), Agricultural Research Service (ARS), U.S. Department of Agriculture (USDA) is responsible for developing and maintaining composition databases for foods and supplements. Recent hypotheses concerning the possible roles of new bioactive dietary compounds in managing...

  14. Marine Bioactives and Potential Application in Sports

    PubMed Central

    Gammone, Maria Alessandra; Gemello, Eugenio; Riccioni, Graziano; D’Orazio, Nicolantonio

    2014-01-01

    An enriched diet with antioxidants, such as vitamin E, vitamin C, β-carotene and phenolic compounds, has always been suggested to improve oxidative stress, preventing related diseases. In this respect, marine natural product (MNP), such as COX inhibitors, marine steroids, molecules interfering with factors involved in the modulation of gene expression (such as NF-κB), macrolides, many antioxidant agents, thermogenic substances and even substances that could help the immune system and that result in the protection of cartilage, have been recently gaining attention. The marine world represents a reserve of bioactive ingredients, with considerable potential as functional food. Substances, such as chitin, chitosan, n-3 oils, carotenoids, vitamins, minerals and bioactive peptides, can provide several health benefits, such as the reduction of cardiovascular diseases, anti-inflammatory and anticarcinogenic activities. In addition, new marine bioactive substances with potential anti-inflammatory, antioxidant and thermogenic capacity may provide health benefits and performance improvement, especially in those who practice physical activity, because of their increased free radical and Reacting Oxygen Species (ROS) production during exercise, and, particularly, in athletes. The aim of this review is to examine the potential pharmacological properties and application of many marine bioactive substances in sports. PMID:24796298

  15. Nanochemoprevention by Bioactive Food Components: A Perspective

    PubMed Central

    Siddiqui, Imtiaz A.

    2010-01-01

    Chemoprevention through the use of bioactive food components is a practical approach for cancer control. Despite abundant efficacy data under preclinical settings, this strategy has resulted in limited success for human cancer control. Amongst many reasons, inefficient systemic delivery and bioavailability of promising chemopreventive agents are considered to significantly contribute to such a disconnect. We recently introduced a novel concept in which we utilized nanotechnology for enhancing the outcome of chemoprevention (Cancer Res. 2009; 69:1712–6) and termed it nanochemoprevention. To establish the proof-of-principle of nanotechnology for cancer management, we determined the efficacy of a well-known chemopreventive agent epigallocatechin-3-gallate (EGCG) encapsulated in polylactic acid (PLA)-polyethylene glycol (PEG) nanoparticles in preclinical settings and observed that, compared to non-encapsulated EGCG, nano-EGCG retained its biological efficacy with over 10-fold dose advantage both in cell culture system and in vivo settings in athymic nude mice implanted with human prostate cancer cells. This study laid the foundation of nanochemoprevention by bioactive food components. Since oral consumption is the most desirable and acceptable form of delivery of bioactive food components, it will be important to develop nanoparticles containing bioactive food components that are suitable for oral consumption for which experiments are underway in this laboratory. PMID:20221894

  16. Bioactive terpenes from marine-derived fungi.

    PubMed

    Elissawy, Ahmed M; El-Shazly, Mohamed; Ebada, Sherif S; Singab, AbdelNasser B; Proksch, Peter

    2015-04-01

    Marine-derived fungi continue to be a prolific source of secondary metabolites showing diverse bioactivities. Terpenoids from marine-derived fungi exhibit wide structural diversity including numerous compounds with pronounced biological activities. In this review, we survey the last five years' reports on terpenoidal metabolites from marine-derived fungi with particular attention on those showing marked biological activities. PMID:25854644

  17. Assessing Antibacterial Potential of Components of Phyllomedusa distincta Skin and its Associated Dermal Microbiota.

    PubMed

    Brito de Assis, Ananda; Dos Santos, Cristiane; Dutra, Flávia Pereira; de Oliveira Motta, Ailla; Costa, Flávio Silva; Navas, Carlos Arturo; Magalhães, Beatriz Simas; Barreto, Cristine Chaves

    2016-02-01

    The granular glands of anuran skin secrete an array of bioactive molecules that protect a frog against pathogens and predators. The skin also harbors a microbial community. Although there is evidence to suggest that the microbiota complement the innate immune defense systems against pathogen infection, the effect of the frog bioactive molecules on its resident microbiota has not yet been fully investigated. In the present study, the skin microbiota of Phyllomedusa distincta obtained from two different geographical areas was evaluated with molecular and culture-based approaches. The antagonistic effects exhibited by the host's microbiota and by a novel dermaseptin peptide isolated from P. distincta skin were investigated. Four isolated bacterial colonies displayed antimicrobial activity against known frog pathogens. Our results were consistent with the hypothesis that microbiota from P. distincta may interact with pathogenic microorganisms to protect a frog's health. On the other hand, the novel dermaseptin peptide exhibited an antimicrobial effect on pathogens as well as on some of the bacteria obtained from the skin microbiota. The richness of bacteria on P. distincta skin was further investigated by 16S rRNA gene clone libraries, which revealed that the family Enterobacteriaceae was prevalent, but a high variability at the species level was observed among individual frogs. Differences observed on the microbiota of frogs from contrasting habitats indicated an influence of the environment on the structure of the skin microbiota of P. distincta. PMID:26826104

  18. Preparation and bioactive properties of nano bioactive glass and segmented polyurethane composites.

    PubMed

    Aguilar-Pérez, Fernando J; Vargas-Coronado, Rossana F; Cervantes-Uc, Jose M; Cauich-Rodríguez, Juan V; Covarrubias, Cristian; Pedram-Yazdani, Merhdad

    2016-04-01

    Composites of glutamine-based segmented polyurethanes with 5 to 25 wt.% bioactive glass nanoparticles were prepared, characterized, and their mineralization potential was evaluated in simulated body fluid. Biocompatibility with dental pulp stem cells was assessed by MTS to an extended range of compositions (1 to 25 wt.% of bioactive glass nanoparticles). Physicochemical characterization showed that composites retained many of the matrix properties, i.e. those corresponding to semicrystalline elastomeric polymers as they exhibited a glass transition temperature (Tg) between -41 and -36℃ and a melting temperature (Tm) between 46 and 49℃ in agreement with X-ray reflections at 23.6° and 21.3°. However, with bioactive glass nanoparticles addition, tensile strength and strain were reduced from 22.2 to 12.2 MPa and 667.2 to 457.8%, respectively with 25 wt.% of bioactive glass nanoparticles. Although Fourier transform infrared spectroscopy did not show evidence of mineralization after conditioning of these composites in simulated body fluid, X-ray diffraction, scanning electron microscopy, and energy dispersive X-ray microanalysis showed the formation of an apatite layer on the surface which increased with higher bioactive glass concentrations and longer conditioning time. Dental pulp stem cells proliferation at day 5 was improved in bioactive glass nanoparticles composites containing lower amounts of the filler (1-2.5 wt.%) but it was compromised at day 9 in composites containing high contents of nBG (5, 15, 25 wt.%). However, Runx2 gene expression was particularly upregulated for the dental pulp stem cells cultured with composites loaded with 15 and 25 wt.% of bioactive glass nanoparticles. In conclusion, low content bioactive glass nanoparticles and segmented polyurethanes composites deserve further investigation for applications such as guided bone regeneration membranes, where osteoconductivity is desirable but not a demanding mechanical performance. PMID:26767396

  19. Effect of nanoparticulate bioactive glass particles on bioactivity and cytocompatibility of poly(3-hydroxybutyrate) composites

    PubMed Central

    Misra, Superb K.; Ansari, Tahera; Mohn, Dirk; Valappil, Sabeel P.; Brunner, Tobias J.; Stark, Wendelin J.; Roy, Ipsita; Knowles, Jonathan C.; Sibbons, Paul D.; Jones, Eugenia Valsami; Boccaccini, Aldo R.; Salih, Vehid

    2010-01-01

    This work investigated the effect of adding nanoparticulate (29 nm) bioactive glass particles on the bioactivity, degradation and in vitro cytocompatibility of poly(3-hydroxybutyrate) (P(3HB)) composites/nano-sized bioactive glass (n-BG). Two different concentrations (10 and 20 wt %) of nanoscale bioactive glass particles of 45S5 Bioglass composition were used to prepare composite films. Several techniques (Raman spectroscopy, scanning electron microscopy, atomic force microscopy, energy dispersive X-ray) were used to monitor their surface and bioreactivity over a 45-day period of immersion in simulated body fluid (SBF). All results suggested the P(3HB)/n-BG composites to be highly bioactive, confirmed by the formation of hydroxyapatite on material surfaces upon immersion in SBF. The weight loss and water uptake were found to increase on increasing bioactive glass content. Cytocompatibility study (cell proliferation, cell attachment, alkaline phosphatase activity and osteocalcin production) using human MG-63 osteoblast-like cells in osteogenic and non-osteogenic medium showed that the composite substrates are suitable for cell attachment, proliferation and differentiation. PMID:19640877

  20. Effect of nanoparticulate bioactive glass particles on bioactivity and cytocompatibility of poly(3-hydroxybutyrate) composites.

    PubMed

    Misra, Superb K; Ansari, Tahera; Mohn, Dirk; Valappil, Sabeel P; Brunner, Tobias J; Stark, Wendelin J; Roy, Ipsita; Knowles, Jonathan C; Sibbons, Paul D; Jones, Eugenia Valsami; Boccaccini, Aldo R; Salih, Vehid

    2010-03-01

    This work investigated the effect of adding nanoparticulate (29 nm) bioactive glass particles on the bioactivity, degradation and in vitro cytocompatibility of poly(3-hydroxybutyrate) (P(3HB)) composites/nano-sized bioactive glass (n-BG). Two different concentrations (10 and 20 wt %) of nanoscale bioactive glass particles of 45S5 Bioglass composition were used to prepare composite films. Several techniques (Raman spectroscopy, scanning electron microscopy, atomic force microscopy, energy dispersive X-ray) were used to monitor their surface and bioreactivity over a 45-day period of immersion in simulated body fluid (SBF). All results suggested the P(3HB)/n-BG composites to be highly bioactive, confirmed by the formation of hydroxyapatite on material surfaces upon immersion in SBF. The weight loss and water uptake were found to increase on increasing bioactive glass content. Cytocompatibility study (cell proliferation, cell attachment, alkaline phosphatase activity and osteocalcin production) using human MG-63 osteoblast-like cells in osteogenic and non-osteogenic medium showed that the composite substrates are suitable for cell attachment, proliferation and differentiation. PMID:19640877

  1. Thermal analysis and in vitro bioactivity of bioactive glass-alumina composites

    SciTech Connect

    Chatzistavrou, Xanthippi; Kantiranis, Nikolaos; Kontonasaki, Eleana; Chrissafis, Konstantinos; Papadopoulou, Labrini; Koidis, Petros; Boccaccini, Aldo R.; Paraskevopoulos, Konstantinos M.

    2011-01-15

    Bioactive glass-alumina composite (BA) pellets were fabricated in the range 95/5-60/40 wt.% respectively and were heat-treated under a specific thermal treatment up to 950 {sup o}C. Control (unheated) and heat-treated pellets were immersed in Simulated Body Fluid (SBF) for bioactivity testing. All pellets before and after immersion in SBF were studied by Fourier Transform Infrared spectroscopy (FTIR), Scanning Electron Microscopy (SEM-EDS) and X-ray Diffraction (XRD) analysis. All composite pellets presented bioactive response. On the surface of the heat-treated pellets the development of a rich biological hydroxyapatite (HAp) layer was delayed for one day, compared to the respective control pellets. Independent of the proportion of the two components, all composites of each group (control and heat-treated) presented the same bioactive response as a function of immersion time in SBF. It was found that by the applied methodology, Al{sub 2}O{sub 3} can be successfully applied in bioactive glass composites without obstructing their bioactive response. - Research Highlights: {yields} Isostatically pressed glass-alumina composites presented apatite-forming ability. {yields} The interaction with SBF resulted in an aluminium phosphate phase formation. {yields} The formation of an aluminium phosphate phase enhanced the in vitro apatite growth.

  2. The versatile temporoparietal fascial flap: adaptability to a variety of composite defects.

    PubMed

    Rose, E H; Norris, M S

    1990-02-01

    The unique properties of the temporoparietal fascial flap (TPFF) offer adaptability in reconstruction of a variety of composite defects. The broad, thin sheet of vascularized tissue may be transferred alone or as a carrier of subjacent bone or overlying skin and scalp. As a pedicled flap, it is ideal for defects of the orbital, malar, mandibular, and mastoid regions. As a free-tissue transfer, the large vessels and lack of bulk find broad utility in reconstruction of the extremities. This flap is our choice for reconstruction of the dorsal hand and non-weight-bearing surfaces of the foot. A viscous gliding surface decreases friction for tendon excursion. The thin contour is aesthetically superior to thicker flaps, allowing unmodified footwear or gloves. The pliable fascia convolutes into surface defects (e.g., bone craters) or drapes over skeletal frameworks (e.g., ear cartilage). The rich capillary network offers nutrition to saucerized bone, cartilage or tendon grafts, and overlying skin grafts. The geometry of the skull lends to fabrication of membranous bone for complex facial puzzles. The donor site is well disguised by hair growth. Twelve cases performed over a 2-year period demonstrate the versatility of this flap. These include complex foot reconstruction, ear and scalp avulsion, shotgun wound of the cheek and orbit, posttraumatic jaw recontouring, chronic osteomyelitis of the hand and foot, and acute resurfacing of dorsal hand with tendon reconstruction. PMID:1967843

  3. Modern skin cleansers.

    PubMed

    Ertel, K

    2000-10-01

    The course of development of skin cleansers has been one of continual improvement. Soap-based products, used since antiquity, offered improved cleansing over mechanical methods or water alone but could irritate and dry skin. Bars based on synthetic detergents that offer improved skin compatibility compared with soap have become available over the past several decades. Body washes have been growing in consumer popularity. Some of the first body washes introduced into the market offered a moisturization benefit in addition to mildness. Some second-generation body washes that are now on the market use even more sophisticated formulation schemes, such as coacervate technology, to deliver emulsified petrolatum to the skin during washing, providing mild cleansing and a significant dry skin improvement benefit. Consumer demand and the formulation possibilities provided by new product formats, new technologies, and new ingredients will undoubtedly lead to the delivery of even greater skin benefits in the future. PMID:11059364

  4. Microcoblation: nonablative skin rejuvenation.

    PubMed

    Abraham, Manoj T; Keller, Gregory S; Pinkosky, Gayla; Feibleman, Cary E; Kelly, James; Man, Daniel; Glenn, Marcia

    2004-02-01

    Microcoblation is the application of a controlled high-energy plasma field to intact aging skin. The treatment is nonablative and yields predictable, reversible histological changes in the epidermis, which result in skin rejuvenation. Recovery time and side effects are minimal. Although the mechanism of action is different, patient satisfaction with microcoblation compares very favorably with microdermabrasion, the traditional method of superficial skin rejuvenation. PMID:15034814

  5. Fungal Skin Infections

    MedlinePLUS

    ... of Fungal Skin Infections Candidiasis Overview of Dermatophytoses (Ringworm, Tinea) Athlete's Foot Jock Itch Scalp Ringworm Body Ringworm Beard Ringworm Dermatophytid Reaction Tinea Versicolor ...

  6. Neuroendocrinology of the skin

    PubMed Central

    Zmijewski, Michal A

    2011-01-01

    The concept on the skin neuro-endocrine has been formulated ten years ago, and recent advances in the field further strengthened this role. Thus, skin forms a bidirectional platform for a signal exchange with other peripheral organs, endocrine and immune systems or brain to enable rapid and selective responses to the environment in order to maintain local and systemic homeostasis. In this context, it is not surprising that the function of the skin is tightly regulated by systemic neuro-endocrine system. Skin cells and skin appendages not only respond to neuropeptides, steroids and other regulatory signals, but also actively synthesis variety of hormones. The stress responses within the skin are tightly regulated by locally synthesized factors and their receptor expression. There is growing evidence for alternative splicing playing an important role in stress signaling. Deregulation of the skin neuro-endocrine signaling can lead or/and be a marker of variety of skin diseases. The major problem in this area relates to their detailed mechanisms of crosstalk between skin and brain and between the local and global endocrine as well as immune systems. PMID:21519402

  7. Bacterial Skin Infections.

    PubMed

    Ibrahim, Fadi; Khan, Tariq; Pujalte, George G A

    2015-12-01

    Skin and soft tissue infections account for 0.5% of outpatient visits to primary care. Skin and soft tissue infections can usually be managed in an outpatient setting. However, there are certain circumstances as discussed in this article that require more urgent care or inpatient management. Primary care providers should be able to diagnose, manage, and provide appropriate follow-up care for these frequently seen skin infections. This article provides family physicians with a comprehensive review of the assessment and management of common bacterial skin infections. PMID:26612370

  8. Skin too thin? The developing utility of zebrafish skin (neuro)pharmacology for CNS drug discovery research.

    PubMed

    Nguyen, Michael; Poudel, Manoj K; Stewart, Adam Michael; Kalueff, Allan V

    2013-09-01

    Skin coloration can be affected by many genetic, environmental and pharmacological factors. Zebrafish (Danio rerio) are a useful and versatile model organism in biomedical research due to their genetic tractability, physiological homology to mammals, low cost, reproducibility and high throughput. Zebrafish coloration is mediated by chromatophores - the skin color pigment cells largely controlled by endocrine and neural mechanisms. The characteristic darkening of zebrafish skin is caused by the dispersion (and paling - by aggregation) of melanosomes (pigment-containing organelles), which show high homology to mammalian structures. Various pharmacological agents potently affect zebrafish coloration - the phenotype that often accompanies behavioral effects of the drugs, and may be used for drug discovery. Although zebrafish behavior and skin responses are usually not directly related, they share common regulatory (neural, endocrine) mechanisms, and therefore may be assessed in parallel during psychotropic drug screening. For example, some psychoactive drugs can potently affect zebrafish skin coloration. Can we use this knowledge to refine phenotype-driven psychotropic drug discovery? Here, we present current models using zebrafish skin coloration assays, and discuss how these models may be applied to enhance in vivo CNS drug discovery. PMID:24007957

  9. Bread enriched in lycopene and other bioactive compounds by addition of dry tomato waste.

    PubMed

    Nour, Violeta; Ionica, Mira Elena; Trandafir, Ion

    2015-12-01

    The tomato processing industry generates high amounts of waste, mainly tomato skins and seeds, which create environmental problems. These residues are attractive sources of valuable bioactive components and pigments. A relatively simple recovery technology could consist of production of powders to be directly incorporated into foods. Tomato waste coming from a Romanian tomato processing unit were analyzed for the content of several bioactive compounds like ascorbic acid, β-carotene, lycopene, total phenolics, mineral and trace elements. In addition, its antioxidant capacity was assayed. Results revealed that tomato waste (skins and seeds) could be successfully utilized as functional ingredient for the formulation of antioxidant rich functional foods. Dry tomato processing waste were used to supplement wheat flour at 6 and 10 % levels (w/w flour basis) and the effects on the bread's physicochemical, baking and sensorial characteristics were studied. The following changes were observed: increase in moisture content, titratable acidity and bread crumb elasticity, reduction in specific volume and bread crumb porosity. The addition of dry tomato waste at 6 % resulted in bread with good sensory characteristics and overall acceptability but as the amount of dry tomato waste increased to 10 %, bread was less acceptable. PMID:26604402

  10. Contribution to the Determination of In Vivo Mechanical Characteristics of Human Skin by Indentation Test

    PubMed Central

    Zahouani, Hassan

    2013-01-01

    This paper proposes a triphasic model of intact skin in vivo based on a general phenomenological thermohydromechanical and physicochemical (THMPC) approach of heterogeneous media. The skin is seen here as a deforming stratified medium composed of four layers and made out of different fluid-saturated materials which contain also an ionic component. All the layers are treated as linear, isotropic materials described by their own behaviour law. The numerical simulations of in vivo indentation test performed on human skin are given. The numerical results correlate reasonably well with the typical observations of indented human skin. The discussion shows the versatility of this approach to obtain a better understanding on the mechanical behaviour of human skin layers separately. PMID:24324525

  11. Contribution to the determination of in vivo mechanical characteristics of human skin by indentation test.

    PubMed

    Abellan, Marie-Angle; Zahouani, Hassan; Bergheau, Jean-Michel

    2013-01-01

    This paper proposes a triphasic model of intact skin in vivo based on a general phenomenological thermohydromechanical and physicochemical (THMPC) approach of heterogeneous media. The skin is seen here as a deforming stratified medium composed of four layers and made out of different fluid-saturated materials which contain also an ionic component. All the layers are treated as linear, isotropic materials described by their own behaviour law. The numerical simulations of in vivo indentation test performed on human skin are given. The numerical results correlate reasonably well with the typical observations of indented human skin. The discussion shows the versatility of this approach to obtain a better understanding on the mechanical behaviour of human skin layers separately. PMID:24324525

  12. The mixture of different parts of Nelumbo nucifera and two bioactive components inhibited tyrosinase activity and melanogenesis.

    PubMed

    Jung, Su-Young; Jung, Won-Seok; Jung, Ho-Kyung; Lee, Gyeong-Hwan; Cho, Jung-Hee; Cho, Hyun-Woo; Choi, In-Young

    2014-01-01

    Melanin is the pigment responsible for the color of the eyes, hair, and skin in humans. Tyrosinase is well known to be the key enzyme in melanin biosynthesis. JKTM-12 is composed of the flowers, roots, seeds, and receptacles of Nelumbo nucifera (lotus). In this study, JKTM-12 was investigated for its inhibitory effects on tyrosinase activity and melanin biosynthesis in B16F10 melanoma cells. Moreover, two main bioactive compounds (hyperoside and astragalin) were found from the receptacles of N. nucifera, which are used as the main material of JKTM-12. JKTM-12 was shown to inhibit tyrosinase activity and melanin biosynthesis in alpha-melanocyte-stimulating hormone-stimulated B16F10 melanoma cells. Hyperoside and astragalin, which are the main bioactive compounds of JKTM-12, not only inhibited tyrosinase activity and melanogenesis but also tyrosinase-related protein 1 and tyrosinase-related protein 2 mRNA expression without cytotoxicity at various experiment doses (0.1, 1, and 10 μg/ml). These results suggest that JKTM-12 has the potential for skin whitening with hyperoside and astragalin as the main bioactive compounds. PMID:25898764

  13. Microencapsulated Bioactive Agents and Method of Making

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R. (Inventor); Mosier, Benjamin (Inventor)

    2003-01-01

    The invention is directed to microcapsules encapsulating an aqueous solution of a protein, drug or other bioactive substance inside a semi-permeable membrane. The microcapsules are formed by interfacial coacervation where shear forces are limited to 0-100 dynes per square centimeter. The resulting uniform microcapsules can then be subjected to dewatering in order to cause the internal solution to become supersaturated with the dissolved substance. This dewatering allows controlled nucleation and crystallization of the dissolved substance. The crystal-filled microcapsules can be stored, keeping the encapsulated crystals in good condition for further direct use in x-ray crystallography or as injectable formulations of the dissolved drug, protein or other bioactive substance.

  14. Bioactive Foods and Ingredients for Health12

    PubMed Central

    Weaver, Connie M.

    2014-01-01

    Bioactive compounds in foods have been gaining interest, and processes to consider them for public health recommendations are being discussed. However, the evidence base is difficult to assemble. It is difficult to demonstrate causality, and there often is not a single compound–single effect relation. Furthermore, health benefits may be due to metabolites produced by the host or gut microbiome rather than the food constituent per se. Properties that can be measured in a food may not translate to in vivo health effects. Compounds that are being pursued may increase gut microbial diversity, improve endothelial function, improve cognitive function, reduce bone loss, and so forth. A new type of bioactive component is emerging from epigenetic modifications by our diet, including microRNA transfer from our diet, which can regulate expression of human genes. Policy processes are needed to establish the level of evidence needed to determine dietary advice and policy recommendations and to set research agendas. PMID:24829482

  15. Skin Diseases: Skin and Sun—Not a good mix

    MedlinePLUS

    ... Current Issue Past Issues Skin Diseases Skin and Sun —Not a good mix Past Issues / Fall 2008 ... turn Javascript on. Good skin care begins with sun safety. Whether it is something as simple as ...

  16. Versatile Desktop Experiment Module (DEMo) on Heat Transfer

    ERIC Educational Resources Information Center

    Minerick, Adrienne R.

    2010-01-01

    This paper outlines a new Desktop Experiment Module (DEMo) engineered for a chemical engineering junior-level Heat Transfer course. This new DEMo learning tool is versatile, fairly inexpensive, and portable such that it can be positioned on student desks throughout a classroom. The DEMo system can illustrate conduction of various materials,

  17. Becoming a More Versatile Learner. An Ideas into Action Guidebook.

    ERIC Educational Resources Information Center

    Dalton, Maxine A.

    Learning from job experiences is essential for every manager's development. Managers learn best from challenging experiences, when employing a variety of learning experiences, and when employing strategies that coordinate what they want to learn with challenges likely to teach these lessons. Becoming a more versatile learner is essential. There

  18. Criminal Careers and Cognitive Scripts: An Investigation into Criminal Versatility

    ERIC Educational Resources Information Center

    Gavin, Helen; Hockey, David

    2010-01-01

    "Criminal careers" denotes ways in which offenders develop specialisms and versatility, but studies linking delinquency to social skills deficits have not attempted to explore cognitive, internalised processes by which such "careers" might be chosen. This study investigated criminal minds via script theory: "internal" scripts are used to guide

  19. Versatile routes to marine sponge metabolites through benzylidene rhodanines.

    PubMed

    Kottakota, Suresh K; Benton, Mathew; Evangelopoulos, Dimitrios; Guzman, Juan D; Bhakta, Sanjib; McHugh, Timothy D; Gray, Mark; Groundwater, Paul W; Marrs, Emma C L; Perry, John D; Harburn, J Jonathan

    2012-12-21

    The first total synthesis of the marine natural products Psammaplin C and Tokaradine A is described. Benzylidene rhodanines were utilized as versatile intermediates toward the synthesis of seven brominated marine sponge metabolites through the optimization of protection group strategies. Spermatinamine demonstrated good inhibition of all cancer cell lines tested, in particular the leukemia K562 and colon cancer HT29 cell lines. PMID:23234337

  20. Versatile Desktop Experiment Module (DEMo) on Heat Transfer

    ERIC Educational Resources Information Center

    Minerick, Adrienne R.

    2010-01-01

    This paper outlines a new Desktop Experiment Module (DEMo) engineered for a chemical engineering junior-level Heat Transfer course. This new DEMo learning tool is versatile, fairly inexpensive, and portable such that it can be positioned on student desks throughout a classroom. The DEMo system can illustrate conduction of various materials,…

  1. Skin problems in children.

    PubMed

    Verbov, J L

    1976-09-01

    Common skin problems in 340 children routinely seen during a winter period, included napkin rashes in infants, atopic eczema throughout childrhood, and acne vulgaris in late childhood. Skin infections and psoriasis were also commonly seen. If possible, when topical steroid preparations more potent than hydrocortisone cream BPC are used in children, they should be used sparingly and for short periods only. PMID:135974

  2. Complications of skin biopsy

    PubMed Central

    Abhishek, Kumar; Khunger, Niti

    2015-01-01

    Skin biopsy is the most commonly performed procedure by the dermatologist. Though it is a safe and easy procedure yet complications may arise. Post operative complications like wound infection and bleeding may occur. It is essential to keep the potential complications of skin biopsy in mind and be meticulous in the technique, for better patient outcomes. PMID:26865792

  3. Biothermomechanics of skin tissues

    NASA Astrophysics Data System (ADS)

    Xu, F.; Lu, T. J.; Seffen, K. A.

    Biothermomechanics of skin is highly interdisciplinary involving bioheat transfer, burn damage, biomechanics and neurophysiology. During heating, thermally induced mechanical stress arises due to the thermal denaturation of collagen, resulting in macroscale shrinkage. Thus, the strain, stress, temperature and thermal pain/damage are highly correlated; in other words, the problem is fully coupled. The aim of this study is to develop a computational approach to examine the heat transfer process and the heat-induced mechanical response, so that the differences among the clinically applied heating modalities can be quantified. Exact solutions for temperature, thermal damage and thermal stress for a single-layer skin model were first derived for different boundary conditions. For multilayer models, numerical simulations using the finite difference method (FDM) and finite element method (FEM) were used to analyze the temperature, burn damage and thermal stress distributions in the skin tissue. The results showed that the thermomechanical behavior of skin tissue is very complex: blood perfusion has little effect on thermal damage but large influence on skin temperature distribution, which, in turn, influences significantly the resulting thermal stress field; the stratum corneum layer, although very thin, has a large effect on the thermomechanical behavior of skin, suggesting that it should be properly accounted for in the modeling of skin thermal stresses; the stress caused by non-uniform temperature distribution in the skin may also contribute to the thermal pain sensation.

  4. Tanning and skin cancer.

    PubMed

    Abdulla, Farah R; Feldman, Steven R; Williford, Phillip M; Krowchuk, Daniel; Kaur, Mandeep

    2005-01-01

    Skin cancer is a large and growing problem in the United States. Sun and other ultraviolet (UV) light exposures play a key role in the development of skin cancer. Pediatricians can play an important role in counseling patients and are in a position to help educate children and their families about skin cancer. The purpose of this review is to familiarize pediatricians with the magnitude of the skin cancer problem and the evidence that ultraviolet light exposure, particularly indoor tanning, contributes to this problem. We reviewed the literature on ultraviolet light and skin cancer (based on a MEDLINE search of articles using the headings "ultraviolet light" and "skin cancer") and found that skin cancer is the most rapidly growing cause of cancer deaths in the United State. There is strong epidemiologic evidence for the relationship between UV exposure and nonmelanoma skin cancer and growing evidence for the relationship between indoor tanning and melanoma. We recommend that pediatricians counsel children and their parents about UV protection. Measures such as use of sunscreen and hats for outdoor play, both at home and in school, should be encouraged. PMID:16354251

  5. Sun on Skin.

    ERIC Educational Resources Information Center

    Collins, Margaret

    1998-01-01

    Describes sessions in two schools that focused on recent work with 2,857 children in Europe researching the children's perceptions of sun on skin. Investigates children's ideas about skin on different parts of the body, which was most vulnerable to the sun, and different types and colors. (Author/CCM)

  6. Bacterial Skin Infections

    MedlinePLUS

    ... well because they have a weakened immune system. Skin that is inflamed or damaged by sunburn, scratching, or other trauma is more likely to become infected. In fact, any break in the skin predisposes a person to infection. Prevention involves keeping ...

  7. Novel bioresorbable and bioactive composites based on bioactive glass and polylactide foams for bone tissue engineering.

    PubMed

    Roether, J A; Gough, J E; Boccaccini, A R; Hench, L L; Maquet, V; Jrme, R

    2002-12-01

    Bioresorbable and bioactive tissue engineering scaffolds based on bioactive glass (45S5 Bioglass(R)) particles and macroporous poly(DL-lactide) (PDLLA) foams were fabricated. A slurry dipping technique in conjunction with pretreatment in ethanol was used to achieve reproducible and well adhering bioactive glass coatings of uniform thickness on the internal and external surfaces of the foams. In vitro studies in simulated body fluid (SBF) demonstrated rapid hydroxyapatite (HA) formation on the surface of the composites, indicating their bioactivity. For comparison, composite foams containing Bioglass(R) particles as filler for the polymer matrix (in concentration of up to 40 wt %) were prepared by freeze-drying, enabling homogenous glass particle distribution in the polymer matrix. The formation of HA on the composite surfaces after immersion in phosphate buffer saline (PBS) was investigated to confirm the bioactivity of the composites. Human osteoblasts (HOBs) were seeded onto as-fabricated PDLLA foams and onto PDLLA foams coated with Bioglass(R) particles to determine early cell attachment and spreading. Cells were observed to attach and spread on all surfaces after the first 90 min in culture. The results of this study indicate that the fabricated composite materials have potential as scaffolds for guided bone regeneration. PMID:15348667

  8. Bioactivity of tape cast and sintered bioactive glass-ceramic in simulated body fluid.

    PubMed

    Clupper, Daniel C; Mecholsky, John J; LaTorre, Guy P; Greenspan, David C

    2002-06-01

    A common ceramic processing technique, tape casting, was used to produce thin, flexible sheets of bioactive glass (Bioglass 45S5) particulate in an organic matrix. Tape casting offers the possibility of producing three-dimensional shapes, as the final material is built up layer by layer. Bioactive glass tapes were sintered together to form small discs for in vitro bioactivity testing in simulated body fluid (SBF). Four different sintering schedules were investigated: 800, 900, and 1000 degrees C for 3 h; and 1000 degrees C for 6 h. Each schedule produced a crystalline material of major phase Na2Ca2Si3O9. Tape cast and sintered bioactive glass-ceramic processed at 1000 degrees C formed crystalline hydroxyapatite layers after 20-24 h in SBF as indicated by Fourier transform infrared spectroscopy, Scanning electron microscopy, and EDS data. FTIR revealed that the greatest amount of hydroxyapatite formation after 2 h was observed for samples sintered at 900 degrees C. The differences in bioactive response were likely caused by the variation in the extent of sintering and, consequently, the amount of surface area available for reaction with SBF. PMID:12033609

  9. Fluoride-containing bioactive glasses: Glass design, structure, bioactivity, cellular interactions, and recent developments.

    PubMed

    Shah, Furqan A

    2016-01-01

    Bioactive glasses (BGs) are known to bond to both hard and soft tissues. Upon exposure to an aqueous environment, BG undergoes ion exchange, hydrolysis, selective dissolution and precipitation of an apatite layer on their surface, which elicits an interfacial biological response resulting in bioactive fixation, inhibiting further dissolution of the glass, and preventing complete resorption of the material. Fluorine is considered one of the most effective in-vivo bone anabolic factors. In low concentrations, fluoride ions (F(-)) increase bone mass and mineral density, improve the resistance of the apatite structure to acid attack, and have well documented antibacterial properties. F(-) ions may be incorporated into the glass in the form of calcium fluoride (CaF2) either by part-substitution of network modifier oxides, or by maintaining the ratios of the other constituents relatively constant. Fluoride-containing bioactive glasses (FBGs) enhance and control osteoblast proliferation, differentiation and mineralisation. And with their ability to release fluoride locally, FBGs make interesting candidates for various clinical applications, dentinal tubule occlusion in the treatment of dentin hypersensitivity. This paper reviews the chemistry of FBGs and the influence of F(-) incorporation on the thermal properties, bioactivity, and cytotoxicity; and novel glass compositions for improved mechanical properties, processing, and bioactive potential. PMID:26478431

  10. Minimum information about a bioactive entity (MIABE).

    PubMed

    Orchard, Sandra; Al-Lazikani, Bissan; Bryant, Steve; Clark, Dominic; Calder, Elizabeth; Dix, Ian; Engkvist, Ola; Forster, Mark; Gaulton, Anna; Gilson, Michael; Glen, Robert; Grigorov, Martin; Hammond-Kosack, Kim; Harland, Lee; Hopkins, Andrew; Larminie, Christopher; Lynch, Nick; Mann, Romeena K; Murray-Rust, Peter; Lo Piparo, Elena; Southan, Christopher; Steinbeck, Christoph; Wishart, David; Hermjakob, Henning; Overington, John; Thornton, Janet

    2011-09-01

    Bioactive molecules such as drugs, pesticides and food additives are produced in large numbers by many commercial and academic groups around the world. Enormous quantities of data are generated on the biological properties and quality of these molecules. Access to such data - both on licensed and commercially available compounds, and also on those that fail during development - is crucial for understanding how improved molecules could be developed. For example, computational analysis of aggregated data on molecules that are investigated in drug discovery programmes has led to a greater understanding of the properties of successful drugs. However, the information required to perform these analyses is rarely published, and when it is made available it is often missing crucial data or is in a format that is inappropriate for efficient data-mining. Here, we propose a solution: the definition of reporting guidelines for bioactive entities - the Minimum Information About a Bioactive Entity (MIABE) - which has been developed by representatives of pharmaceutical companies, data resource providers and academic groups. PMID:21878981

  11. Analysis of commercial and public bioactivity databases.

    PubMed

    Tiikkainen, Pekka; Franke, Lutz

    2012-02-27

    Activity data for small molecules are invaluable in chemoinformatics. Various bioactivity databases exist containing detailed information of target proteins and quantitative binding data for small molecules extracted from journals and patents. In the current work, we have merged several public and commercial bioactivity databases into one bioactivity metabase. The molecular presentation, target information, and activity data of the vendor databases were standardized. The main motivation of the work was to create a single relational database which allows fast and simple data retrieval by in-house scientists. Second, we wanted to know the amount of overlap between databases by commercial and public vendors to see whether the former contain data complementing the latter. Third, we quantified the degree of inconsistency between data sources by comparing data points derived from the same scientific article cited by more than one vendor. We found that each data source contains unique data which is due to different scientific articles cited by the vendors. When comparing data derived from the same article we found that inconsistencies between the vendors are common. In conclusion, using databases of different vendors is still useful since the data overlap is not complete. It should be noted that this can be partially explained by the inconsistencies and errors in the source data. PMID:22145975

  12. Nanotech: propensity in foods and bioactives.

    PubMed

    Kuan, Chiu-Yin; Yee-Fung, Wai; Yuen, Kah-Hay; Liong, Min-Tze

    2012-01-01

    Nanotechnology is seeing higher propensity in various industries, including food and bioactives. New nanomaterials are constantly being developed from both natural biodegradable polymers of plant and animal origins such as polysaccharides and derivatives, peptides and proteins, lipids and fats, and biocompatible synthetic biopolyester polymers such as polylactic acid (PLA), polyhydroxyalkonoates (PHA), and polycaprolactone (PCL). Applications in food industries include molecular synthesis of new functional food compounds, innovative food packaging, food safety, and security monitoring. The relevance of bioactives includes targeted delivery systems with improved bioavailability using nanostructure vehicles such as association colloids, lipid based nanoencapsulator, nanoemulsions, biopolymeric nanoparticles, nanolaminates, and nanofibers. The extensive use of nanotechnology has led to the need for parallel safety assessment and regulations to protect public health and adverse effects to the environment. This review covers the use of biopolymers in the production of nanomaterials and the propensity of nanotechnology in food and bioactives. The exposure routes of nanoparticles, safety challenges, and measures undertaken to ensure optimal benefits that outweigh detriments are also discussed. PMID:21991990

  13. Epitope topography controls bioactivity in supramolecular nanofibers

    PubMed Central

    Sur, Shantanu; Tantakitti, Faifan; Matson, John B.; Stupp, Samuel I.

    2015-01-01

    Incorporating bioactivity into artificial scaffolds using peptide epitopes present in the extracellular matrix (ECM) is a well-known approach. A common strategy has involved epitopes that provide cells with attachment points and external cues through interaction with integrin receptors. Although a variety of bioactive sequences have been identified so far, less is known about their optimal display in a scaffold. We report here on the use of self-assembled peptide amphiphile (PA) nanofiber matrices to investigate the impact of spatial presentation of the fibronectin derived epitope RGDS on cell response. Using one, three, or five glycine residues, RGDS epitopes were systematically spaced out from the surface of the rigid nanofibers. We found that cell morphology was strongly affected by the separation of the epitope from the nanofiber surface, with the longest distance yielding the most cell-spreading, bundling of actin filaments, and a round-to-polygonal transformation of cell shape. Cell response to this type of epitope display was also accompanied with activated integrin-mediated signaling and formation of stronger adhesions between cells and substrate. Interestingly, unlike length, changing the molecular flexibility of the linker had minimal influence on cell behavior on the substrate for reasons that remain poorly understood. The use in this study of high persistence length nanofibers rather than common flexible polymers allows us to conclude that epitope topography at the nanoscale structure of a scaffold influences its bioactive properties independent of epitope density and mechanical properties. PMID:25745558

  14. Human Milk Composition: Nutrients and Bioactive Factors

    PubMed Central

    Ballard, Olivia; Morrow, Ardythe L.

    2013-01-01

    Synopsis The composition of human milk is the biologic norm for infant nutrition. Human milk also contains many hundreds to thousands of distinct bioactive molecules that protect against infection and inflammation and contribute to immune maturation, organ development, and healthy microbial colonization. Some of these molecules, e.g., lactoferrin, are being investigated as novel therapeutic agents. A dynamic, bioactive fluid, human milk changes in composition from colostrum to late lactation, and varies within feeds, diurnally, and between mothers. Feeding infants with expressed human milk is increasing. Pasteurized donor milk is now commonly provided to high risk infants and most mothers in the U.S. express and freeze their milk at some point in lactation for future infant feedings. Many milk proteins are degraded by heat treatment and freeze-thaw cycles may not have the same bioactivity after undergoing these treatments. This article provides an overview of the composition of human milk, sources of its variation, and its clinical relevance. PMID:23178060

  15. Bioactive peptides of animal origin: a review.

    PubMed

    Bhat, Z F; Kumar, Sunil; Bhat, Hina Fayaz

    2015-09-01

    Bioactive peptides are specific protein fragments which, above and beyond their nutritional capabilities, have a positive impact on the body's function or condition which may ultimately influence health. Although, inactive within the sequence of the parent proteins, these peptides can be released during proteolysis or fermentation and play an important role in human health by affecting the digestive, endocrine, cardiovascular, immune and nervous systems. Several peptides that are released in vitro or in vivo from animal proteins have been attributed to different health effects, including antimicrobial properties, blood pressure-lowering (ACE inhibitory) effects, cholesterol-lowering ability, antithrombotic and antioxidant activities, opioid activities, enhancement of mineral absorption and/or bioavailability, cytomodulatory and immunomodulatory effects, antiobesity, and anti-genotoxic activity. Several functional foods based on the bioactivities of these peptides with scientifically evidenced health claims are already on the market or under development by food companies. Consumer's increasing interest in these products has given an impetus to the food industry and scientific sector who are continuously exploring the possibilities for the development of new functional products based on these peptides. In this review, we describe above stated properties of bioactive peptides of animal origin. PMID:26344955

  16. Adhesive Bioactive Coatings Inspired by Sea Life.

    PubMed

    Rego, Sónia J; Vale, Ana C; Luz, Gisela M; Mano, João F; Alves, Natália M

    2016-01-19

    Inspired by nature, in particular by the marine mussels adhesive proteins (MAPs) and by the tough brick-and-mortar nacre-like structure, novel multilayered films are prepared in the present work. Organic-inorganic multilayered films, with an architecture similar to nacre based on bioactive glass nanoparticles (BG), chitosan, and hyaluronic acid modified with catechol groups, which are the main components responsible for the outstanding adhesion in MAPs, are developed for the first time. The biomimetic conjugate is prepared by carbodiimide chemistry and analyzed by ultraviolet-visible spectrophotometry. The buildup of the multilayered films is monitored with a quartz crystal microbalance with dissipation monitoring, and their topography is characterized by atomic force microscopy. The mechanical properties reveal that the films containing catechol groups and BG present an enhanced adhesion. Moreover, the bioactivity of the films upon immersion in a simulated body fluid solution is evaluated by scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, and X-ray diffraction. It was found that the constructed films promote the formation of bonelike apatite in vitro. Such multifunctional mussel inspired LbL films, which combine enhanced adhesion and bioactivity, could be potentially used as coatings of a variety of implants for orthopedic applications. PMID:26653103

  17. Neuropeptides and skin aging.

    PubMed

    Elewa, Rana; Makrantonaki, Evgenia; Zouboulis, Christos C

    2013-12-01

    Abstract Neuropeptides (NP) are peptides that are released as chemical messengers from nerve cells. They act either in an endocrine manner, where they reach their target cells via the bloodstream or a paracrine manner, as co-transmitters modulating the function of neurotransmitters. To date approximately 100 different NP have been described in the literature. In recent years, several studies have documented that human skin expresses several functional receptors for NP, such as corticotropin-releasing hormone, melanocortins, β-endorphin, vasoactive intestinal polypeptide, neuropeptide Y and calcitonin gene-related peptide. These receptors modulate the production of inflammatory cytokines, proliferation, differentiation, lipogenesis and hormone metabolism in human skin cells. In addition, several NP are directly produced by human skin cells, indicating the complexity of understanding the real functions of NPs in human skin. In this review we address the possible effects of neuropeptides on the pathogenesis of aged skin. PMID:25436744

  18. Skin smoothing surgery - series (image)

    MedlinePLUS

    ... the scar tissue off down to normal, healthy skin. The healing tissue is treated with ointments (such ... The skin may be treated with ointment and a wet or waxy dressing. After surgery, your skin will be ...

  19. 6 Common Cancers - Skin Cancer

    MedlinePLUS

    ... Bar Home Current Issue Past Issues 6 Common Cancers - Skin Cancer Past Issues / Spring 2007 Table of Contents For ... AP Photo/Herald-Mail, Kevin G. Gilbert Skin Cancer Skin cancer is the most common form of ...

  20. Interfacial design for a bioactive composite

    NASA Astrophysics Data System (ADS)

    MacDonald, Jeanne Marie

    2001-07-01

    The objective for this project is to develop a bioactive dental composite showing enhanced mechanical properties through the development of a designed interface and to experimentally evaluate and model these interfaces. The efficiency of the surface modifications is analyzed as it relates to the bioactivity of the filler, a sol-gel derived bioglass (60 mol% SiO2, 36 mol% CaO, 4 mol% P2O5), and to the enhancement of mechanical properties. Among the filler surfaces studied are a methacryloxypropyl triethoxysilane (MAMTES) coupling agent combined with a methyl triethoxysilane (MTES) coupling agent, and a grafted sulfonated polysulfone (SPSF) with different degrees of sulfonation. The resin system chosen is based on 2,2'-bis-(4-methacryloylethoxyphenyl) propane using triethylene glycol dimethacrylate as a diluent to improve processability. To help offset the polymerization shrinkage, nadic methyl anhydride is added Hydrolysis of this anhydride provides a mechanism for offsetting shrinkage. A dependence on the ratio of methacrylate functionalized coupling agent on the reinforcing capabilities of the filler was discovered. This dependence also translates into the stabilization of the interface after a solution soak. Enhanced properties at mid-level ratios of MAMTES to MTES show the importance of the coupling system and not just the presence of a coupling agent to the enhancement of a composite. Evidence of the bioactivity of the composites is seen in a comparison of composite samples after submersion in either pure water or a salt solution. Additional weight gain could be the result of the sorption of HCA forming ions (calcium and phosphate) from the salt solution. The lower weight gain rate for the silanated composite supports a shielding effect of the coupling agent to the bioactivity of the filler. Sulfonated polysulfones were successfully prepared and grafted onto the BioglassRTM filler. A dependence on the level of sulfonation on the reinforcing capabilities of the filler was discovered. At higher degrees of sulfonation there is an increased water attraction at the interface that leads to a higher propensity for hydrolytic degradation and lowered mechanical properties. Along with the lowered mechanical properties, however, there is evidence of HCA growth that is necessary for the condition of bioactivity.

  1. Hiding the squid: patterns in artificial cephalopod skin

    PubMed Central

    Fishman, Aaron; Rossiter, Jonathan; Homer, Martin

    2015-01-01

    Cephalopods employ their chromomorphic skins for rapid and versatile active camouflage and signalling effects. This is achieved using dense networks of pigmented, muscle-driven chromatophore cells which are neurally stimulated to actuate and affect local skin colouring. This allows cephalopods to adopt numerous dynamic and complex skin patterns, most commonly used to blend into the environment or to communicate with other animals. Our ultimate goal is to create an artificial skin that can mimic such pattern generation techniques, and that could produce a host of novel and compliant devices such as cloaking suits and dynamic illuminated clothing. This paper presents the design, mathematical modelling and analysis of a dynamic biomimetic pattern generation system using bioinspired artificial chromatophores. The artificial skin is made from electroactive dielectric elastomer: a soft, planar-actuating smart material that we show can be effective at mimicking the actuation of biological chromatophores. The proposed system achieves dynamic pattern generation by imposing simple local rules into the artificial chromatophore cells so that they can sense their surroundings in order to manipulate their actuation. By modelling sets of artificial chromatophores in linear arrays of cells, we explore the capability of the system to generate a variety of dynamic pattern types. We show that it is possible to mimic patterning seen in cephalopods, such as the passing cloud display, and other complex dynamic patterning. PMID:26063823

  2. Hiding the squid: patterns in artificial cephalopod skin.

    PubMed

    Fishman, Aaron; Rossiter, Jonathan; Homer, Martin

    2015-07-01

    Cephalopods employ their chromomorphic skins for rapid and versatile active camouflage and signalling effects. This is achieved using dense networks of pigmented, muscle-driven chromatophore cells which are neurally stimulated to actuate and affect local skin colouring. This allows cephalopods to adopt numerous dynamic and complex skin patterns, most commonly used to blend into the environment or to communicate with other animals. Our ultimate goal is to create an artificial skin that can mimic such pattern generation techniques, and that could produce a host of novel and compliant devices such as cloaking suits and dynamic illuminated clothing. This paper presents the design, mathematical modelling and analysis of a dynamic biomimetic pattern generation system using bioinspired artificial chromatophores. The artificial skin is made from electroactive dielectric elastomer: a soft, planar-actuating smart material that we show can be effective at mimicking the actuation of biological chromatophores. The proposed system achieves dynamic pattern generation by imposing simple local rules into the artificial chromatophore cells so that they can sense their surroundings in order to manipulate their actuation. By modelling sets of artificial chromatophores in linear arrays of cells, we explore the capability of the system to generate a variety of dynamic pattern types. We show that it is possible to mimic patterning seen in cephalopods, such as the passing cloud display, and other complex dynamic patterning. PMID:26063823

  3. Stochastic simulation of structured skin cell population dynamics.

    PubMed

    Nakaoka, Shinji; Aihara, Kazuyuki

    2013-03-01

    The epidermis is the outmost skin tissue. It operates as a first defense system to process inflammatory signals and responds by producing inflammatory mediators that promote the recruitment of immune cells. Various skin diseases such as atopic dermatitis occur as a result of the defect of proper skin barrier function and successive impaired inflammatory responses. The onset of such a skin disease links to the disturbed epidermal homeostasis regulated by appropriate self-renewal and differentiation of epidermal stem cells. The theory of physiologically structured population models provides a versatile framework to formulate mathematical models which describe the growth dynamics of a cell population such as the epidermis. In this paper, we develop an algorithm to implement stochastic simulation for a class of physiologically structured population models. We demonstrate that the developed algorithm is applicable to several cell population models and typical age-structured population models. On the basis of the developed algorithm, we investigate stochastic dynamics of skin cell populations and spread of inflammation. It is revealed that demographic stochasticity can bring considerable impact on the outcome of inflammation spread at the tissue level. PMID:23255068

  4. Occupational skin disease.

    PubMed

    Peate, W E

    2002-09-15

    Contact dermatitis, the most common occupational skin disease, is characterized by clearly demarcated areas of rash at sites of exposure. The rash improves on removal of the offending agent. In allergic contact dermatitis, even minute exposures to antigenic substances can lead to a skin rash. Common sensitizing agents include nickel and members of the Rhus genus (e.g., poison ivy, poison oak). Severe skin irritants tend to cause immediate red blisters or burns, whereas weaker irritants produce eczematous skin changes over time. An occupational cause should be suspected when rash occurs in areas that are in contact with oil, grease, or other substances. Direct skin testing (patch or scratch) or radioallergosorbent testing may help to identify a specific trigger. Skin cancer can have an occupational link in workers with prolonged exposure to sunlight and certain chemicals, although it can take decades for lesions to develop. In workers with occupational skin disease, workplace changes and protective measures are important to prevent future exposure. PMID:12358214

  5. Skin and antioxidants.

    PubMed

    Poljsak, Borut; Dahmane, Raja; Godic, Aleksandar

    2013-04-01

    It is estimated that total sun exposure occurs non-intentionally in three quarters of our lifetimes. Our skin is exposed to majority of UV radiation during outdoor activities, e.g. walking, practicing sports, running, hiking, etc. and not when we are intentionally exposed to the sun on the beach. We rarely use sunscreens during those activities, or at least not as much and as regular as we should and are commonly prone to acute and chronic sun damage of the skin. The only protection of our skin is endogenous (synthesis of melanin and enzymatic antioxidants) and exogenous (antioxidants, which we consume from the food, like vitamins A, C, E, etc.). UV-induced photoaging of the skin becomes clinically evident with age, when endogenous antioxidative mechanisms and repair processes are not effective any more and actinic damage to the skin prevails. At this point it would be reasonable to ingest additional antioxidants and/or to apply them on the skin in topical preparations. We review endogenous and exogenous skin protection with antioxidants. PMID:23384037

  6. Archaea on Human Skin

    PubMed Central

    Probst, Alexander J.; Auerbach, Anna K.; Moissl-Eichinger, Christine

    2013-01-01

    The recent era of exploring the human microbiome has provided valuable information on microbial inhabitants, beneficials and pathogens. Screening efforts based on DNA sequencing identified thousands of bacterial lineages associated with human skin but provided only incomplete and crude information on Archaea. Here, we report for the first time the quantification and visualization of Archaea from human skin. Based on 16 S rRNA gene copies Archaea comprised up to 4.2% of the prokaryotic skin microbiome. Most of the gene signatures analyzed belonged to the Thaumarchaeota, a group of Archaea we also found in hospitals and clean room facilities. The metabolic potential for ammonia oxidation of the skin-associated Archaea was supported by the successful detection of thaumarchaeal amoA genes in human skin samples. However, the activity and possible interaction with human epithelial cells of these associated Archaea remains an open question. Nevertheless, in this study we provide evidence that Archaea are part of the human skin microbiome and discuss their potential for ammonia turnover on human skin. PMID:23776475

  7. Miniaturized Bioaffinity Assessment Coupled to Mass Spectrometry for Guided Purification of Bioactives from Toad and Cone Snail

    PubMed Central

    Heus, Ferry; Otvos, Reka A.; Aspers, Ruud L. E. G.; van Elk, Rene; Halff, Jenny I.; Ehlers, Andreas W.; Dutertre, Sébastien; Lewis, Richard J.; Wijmenga, Sybren; Smit, August B.; Niessen, Wilfried M. A.; Kool, Jeroen

    2014-01-01

    A nano-flow high-resolution screening platform, featuring a parallel chip-based microfluidic bioassay and mass spectrometry coupled to nano-liquid chromatography, was applied to screen animal venoms for nicotinic acetylcholine receptor like (nAChR) affinity by using the acetylcholine binding protein, a mimic of the nAChR. The potential of this microfluidic platform is demonstrated by profiling the Conus textile venom proteome, consisting of over 1,000 peptides. Within one analysis (<90 min, 500 ng venom injected), ligands are detected and identified. To show applicability for non-peptides, small molecular ligands such as steroidal ligands were identified in skin secretions from two toad species (Bufo alvarius and Bufo marinus). Bioactives from the toad samples were subsequently isolated by MS-guided fractionation. The fractions analyzed by NMR and a radioligand binding assay with α7-nAChR confirmed the identity and bioactivity of several new ligands. PMID:24833338

  8. Miniaturized bioaffinity assessment coupled to mass spectrometry for guided purification of bioactives from toad and cone snail.

    PubMed

    Heus, Ferry; Otvos, Reka A; Aspers, Ruud L E G; van Elk, Rene; Halff, Jenny I; Ehlers, Andreas W; Dutertre, Sbastien; Lewis, Richard J; Wijmenga, Sybren; Smit, August B; Niessen, Wilfried M A; Kool, Jeroen

    2014-01-01

    A nano-flow high-resolution screening platform, featuring a parallel chip-based microfluidic bioassay and mass spectrometry coupled to nano-liquid chromatography, was applied to screen animal venoms for nicotinic acetylcholine receptor like (nAChR) affinity by using the acetylcholine binding protein, a mimic of the nAChR. The potential of this microfluidic platform is demonstrated by profiling the Conus textile venom proteome, consisting of over 1,000 peptides. Within one analysis (<90 min, 500 ng venom injected), ligands are detected and identified. To show applicability for non-peptides, small molecular ligands such as steroidal ligands were identified in skin secretions from two toad species (Bufo alvarius and Bufo marinus). Bioactives from the toad samples were subsequently isolated by MS-guided fractionation. The fractions analyzed by NMR and a radioligand binding assay with ?7-nAChR confirmed the identity and bioactivity of several new ligands. PMID:24833338

  9. [Research development of chemistry and bioactive activity of plant peptides].

    PubMed

    Liang, Yan; Wu, Xiao-qin; Zhang, Ying

    2006-05-01

    As the technologies of separation, purification and determination develop rapidly, more and more peptide compounds, which have special bioactive and medical value, have been separated from natural plants, such as oligopeptides and cyclopeptides. The chemical structures and function of these plant peptides have been researched profoundly. This paper mainly reviews the composition, structure, bioactive function and medicine value of representative plant peptides in recent years, and can give some references about research and application of plant bioactive peptides. PMID:17048672

  10. Silks as scaffolds for skin reconstruction.

    PubMed

    Reimers, Kerstin; Liebsch, Christina; Radtke, Christine; Kuhbier, Jrn W; Vogt, Peter M

    2015-11-01

    In this short review, we describe the use of high molecular weight proteins produced in the glands of several arthropods-commonly called silks-for the purpose to enhance human skin wound healing. To this end an extensive literature search has been performed, the publications have been categorized concerning silk preparation and application and summarized accordingly: Scaffolds to promote wound healing were prepared by processing the silks in different ways including solubilization of the protein fibers followed by casting or electrospinning. The silk scaffolds were additionally modified by coating or blending with the intention of further functionalization. In several approaches, the scaffolds were also vitalized with skin cells or stem cells. In vitro and in vivo models were implied to test for safety and efficiency. We conclude that silk scaffolds are characterized by an advantageous biocompatibility as well as an impressive versatility rendering them ideally suited for application in wounds. Nevertheless, further investigation is needed to exploit the full capacity of silk in different wound models and to achieve clinical transfer in time. Biotechnol. Bioeng. 2015;112: 2201-2205. 2015 Wiley Periodicals, Inc. PMID:25995140

  11. Thermal Skin fabrication technology

    NASA Technical Reports Server (NTRS)

    Milam, T. B.

    1972-01-01

    Advanced fabrication techniques applicable to Thermal Skin structures were investigated, including: (1) chemical machining; (2) braze bonding; (3) diffusion bonding; and (4) electron beam welding. Materials investigated were nickel and nickel alloys. Sample Thermal Skin panels were manufactured using the advanced fabrication techniques studied and were structurally tested. Results of the program included: (1) development of improved chemical machining processes for nickel and several nickel alloys; (2) identification of design geometry limits; (3) identification of diffusion bonding requirements; (4) development of a unique diffusion bonding tool; (5) identification of electron beam welding limits; and (6) identification of structural properties of Thermal Skin material.

  12. Skin Cancer in Asians

    PubMed Central

    Kim, Grace K.; Bellew, Susun

    2009-01-01

    Since the 1960s, basal cell carcinoma and squamous cell carcinoma among the Caucasian population have increased 3 to 8 percent annually. Although Asians display relative protection from basal cell carcinoma and squamous cell carcinoma, incidence rates of these nonmelanoma skin cancers have been increasing over the past three decades. With changing demographics and a steady rise in the minority population in the United States, there is an increased need for further studies of cutaneous malignancies within Asian and other ethnic populations. This article reviews nonmelanoma skin cancers in the Asian population with an insight into contributing factors, such as skin type, occupation, cultural practices, and genetic components. PMID:20729955

  13. Skin Diseases in Horses.

    PubMed

    Wobeser, Bruce K

    2015-08-01

    Skin disease in horses is a common and potentially challenging clinical problem. Information pertaining to skin disease is lacking in horses when compared with that in other companion animal species. Certainly, both horse-specific and location-specific patterns are present, but these can often be confounded by other factors. There are many possible ways in which to organize skin disease; in this article, they are organized based loosely on their most common clinical feature. Space limits the number of conditions that can be described here, and those chosen were seen relatively frequently in a multiinstitutional study of equine biopsies. PMID:26037605

  14. Environmental versatility promotes modularity in genome-scale metabolic networks

    PubMed Central

    2011-01-01

    Background The ubiquity of modules in biological networks may result from an evolutionary benefit of a modular organization. For instance, modularity may increase the rate of adaptive evolution, because modules can be easily combined into new arrangements that may benefit their carrier. Conversely, modularity may emerge as a by-product of some trait. We here ask whether this last scenario may play a role in genome-scale metabolic networks that need to sustain life in one or more chemical environments. For such networks, we define a network module as a maximal set of reactions that are fully coupled, i.e., whose fluxes can only vary in fixed proportions. This definition overcomes limitations of purely graph based analyses of metabolism by exploiting the functional links between reactions. We call a metabolic network viable in a given chemical environment if it can synthesize all of an organism's biomass compounds from nutrients in this environment. An organism's metabolism is highly versatile if it can sustain life in many different chemical environments. We here ask whether versatility affects the modularity of metabolic networks. Results Using recently developed techniques to randomly sample large numbers of viable metabolic networks from a vast space of metabolic networks, we use flux balance analysis to study in silico metabolic networks that differ in their versatility. We find that highly versatile networks are also highly modular. They contain more modules and more reactions that are organized into modules. Most or all reactions in a module are associated with the same biochemical pathways. Modules that arise in highly versatile networks generally involve reactions that process nutrients or closely related chemicals. We also observe that the metabolism of E. coli is significantly more modular than even our most versatile networks. Conclusions Our work shows that modularity in metabolic networks can be a by-product of functional constraints, e.g., the need to sustain life in multiple environments. This organizational principle is insensitive to the environments we consider and to the number of reactions in a metabolic network. Because we observe this principle not just in one or few biological networks, but in large random samples of networks, we propose that it may be a generic principle of metabolic network organization. PMID:21864340

  15. Microencapsulation for the improved delivery of bioactive compounds into foods.

    PubMed

    Champagne, Claude P; Fustier, Patrick

    2007-04-01

    The development of functional foods through the addition of bioactive compounds holds many technological challenges. Microencapsulation is a useful tool to improve the delivery of bioactive compounds into foods, particularly probiotics, minerals, vitamins, phytosterols, lutein, fatty acids, lycopene and antioxidants. Several microencapsulation technologies have been developed for use in the food industry and show promise for the production of functional foods. Moreover, these technologies could promote the successful delivery of bioactive ingredients to the gastrointestinal tract. Future research is likely to focus on aspects of delivery and the potential use of co-encapsulation methodologies, where two or more bioactive ingredients can be combined to have a synergistic effect. PMID:17368017

  16. Bioactive Peptides from Muscle Sources: Meat and Fish

    PubMed Central

    Ryan, Joseph Thomas; Ross, Reynolds Paul; Bolton, Declan; Fitzgerald, Gerald F.; Stanton, Catherine

    2011-01-01

    Bioactive peptides have been identified in a range of foods, including plant, milk and muscle, e.g., beef, chicken, pork and fish muscle proteins. Bioactive peptides from food proteins offer major potential for incorporation into functional foods and nutraceuticals. The aim of this paper is to present an outline of the bioactive peptides identified in the muscle protein of meat to date, with a focus on muscle protein from domestic animals and fish. The majority of research on bioactives from meat sources has focused on angiotensin-1-converting enzyme (ACE) inhibitory and antioxidant peptides. PMID:22254123

  17. Characterization of bioactive peptides obtained from marine invertebrates.

    PubMed

    Lee, Jung Kwon; Jeon, Joong-Kyun; Kim, Se-Kwon; Byun, Hee-Guk

    2012-01-01

    Bioactive peptides as products of hydrolysis of diverse marine invertebrate (shellfish, crustacean, rotifer, etc.) proteins are the focus of current research. After much research on these muscles and by-products, some biologically active peptides were identified and applied to useful compounds for human utilization. This chapter reviews bioactive peptides from marine invertebrates in regarding to their bioactivities. Additionally, specific characteristics of antihypertensive, anti-Alzheimer, antioxidant, antimicrobial peptide enzymatic production, methods to evaluate bioactivity capacity, bioavailability, and safety concerns of peptides are reviewed. PMID:22361180

  18. Are Dietary Bioactives Ready for Recommended Intakes?12

    PubMed Central

    Gaine, P. Courtney; Balentine, Douglas A.; Erdman, John W.; Dwyer, Johanna T.; Ellwood, Kathleen C.; Hu, Frank B.; Russell, Robert M.

    2013-01-01

    Research has shown that numerous dietary bioactive components that are not considered essential may still be beneficial to health. The dietary reference intake (DRI) process has been applied to nonessential nutrients, such as fiber, yet the majority of bioactive components await a recommended intake. Despite a plethora of new research over the past several years on the health effects of bioactives, it is possible that the field may never reach a point where the current DRI framework is suitable for these food components. If bioactives are to move toward dietary guidance, they will likely require an alternative path to get there. PMID:24038250

  19. Bioactive coating with low-fouling polymers for the development of biocompatible vascular implants

    NASA Astrophysics Data System (ADS)

    Thalla, Pradeep Kumar

    The replacement of occluded blood vessels and endovascular aneurysm repair (EVAR) are performed with the use of synthetic vascular grafts and stent grafts, respectively. Both implants lead to frequent clinical complications that are different but due to a similar problem, namely the inadequate surface properties of the polymeric biomaterials used (generally polyethylene terephthalate (PET) or expanded polytetrafluoroethylene (ePTFE)). Therefore the general objective of this thesis was to create a versatile bioactive coating on vascular biomaterials that reduce material-induced thrombosis and promote desired cell interactions favorable to tissue healing around implants. The use of low-fouling backgrounds was decided in order to reduce platelet adhesion as well as the non-specific protein adsorption and thus increase the bioactivity of immobilized biomolecules. As part of the preliminary objective, a multi-arm polyethylene glycol (PEG) was chosen to create a versatile low-fouling surface, since the current coating methods are far from being versatile and rely on the availability of compatible functional groups on both PEG and the host surface. This PEG coating method was developed by taking advantage of novel primary amine-rich plasma polymerized coatings (LP). As demonstrated by quartz crystal microbalance with dissipation (QCM-D), fluorescence measurements and platelet adhesion assays, our PEG coatings exhibited low protein adsorption and almost no platelet adhesion after 15 min perfusion in whole blood. Although protein adsorption was not completely abrogated and short-term platelet adhesion assay was clearly insufficient to draw conclusions for long-term prevention of thrombosis in vivo, the low-fouling properties of this PEG coating were sufficient to be exploited for further coupling of bioactive molecules to create bioactive coatings. Therefore, as a part of the second objective, an innovative and versatile bioactive coating was developed on PEG and carboxymethylated dextran (CMD), using the combination of an adhesive peptide (KQAGDV/RGD) and epidermal growth factor (EGF). CMD was chosen as an alternative to PEG due to its better low-fouling properties and the presence of abundant carboxyl terminal groups. Although the QCM-D technique enabled us to optimize the combined immobilization of KQAGDV/RGD and EGF, cell adhesion assay results did not show improvement of vascular smooth muscle cell (VSMC) adhesion on peptide-modified PEG or CMD surfaces. Among the reasons explaining low cell adhesion on peptides grafted low-fouling surfaces is the difficulty of preventing protein adsorption/platelet adhesion without significantly reducing cell adhesion. Preliminary data in our laboratory indicated that CS could be an ideal substrate to find this compromise. For that reason, the final objective of this PhD consisted in evaluating the potential of chondroitin sulfate (CS) coating by comparing its properties with well-known low-fouling polymers such as PEG and CMD. It was shown that CS presents selective low-fouling properties, low-platelet adhesion and pro-endothelial cell (EC) adhesive properties As demonstrated by QCM-D and fluorescence measurements, CS was as effective as PEG in reducing fibrinogen adsorption, but it reduced adsorption of bovine serum albumin (BSA) and fetal bovine serum (FBS) to a lower extent than PEG and CMD surfaces. Whole blood perfusion assays indicated that all three surfaces drastically decreased platelet adhesion and activation to levels significantly lower than PET surfaces. However, while EC adhesion and growth were found to be very limited on PEG and CMD, cell attachment on CS was strong, with focal adhesion points and resistance to shear stress. CS coatings therefore form a low-thrombogenic background promoting the formation of a confluent endothelium layer, which may then act as an active anti-thrombogenic surface. CS coating can also be used to further graft biomolecules. Combination of LP, CS coating followed by GF immobilization shows great promise as a bioactive coating to optimize the biocompatibility and clinical outcome of vascular implants, in particular vascular grafts.

  20. Characterization of the bioactive and mechanical behavior of dental ceramic/sol-gel derived bioactive glass mixtures.

    PubMed

    Abbasi, Zahra; Bahrololoum, Mohammad E; Bagheri, Rafat; Shariat, Mohammad H

    2016-02-01

    Dental ceramics can be modified by bioactive glasses in order to develop apatite layer on their surface. One of the benefits of such modification is to prolong the lifetime of the fixed dental prosthesis by preventing the formation of secondary caries. Dental ceramic/sol-gel derived bioactive glass mixture is one of the options for this modification. In the current study, mixtures of dental ceramic/bioactive glass with different compositions were successfully produced. To evaluate their bioactive behavior, prepared samples were immersed in a simulated body fluid at various time intervals. The prepared and soaked specimens were characterized using Fourier transform infrared spectroscopy, X-ray diffractometry and scanning electron microscopy. Since bioactive glasses have deleterious effects on the mechanical properties of dental ceramics, 3-point bending tests were used to evaluate the flexural strength, flexural strain, tangent modulus of elasticity and Weibull modulus of the specimens in order to find the optimal relationship between mechanical and bioactive properties. PMID:26454135

  1. Electrospinning of Bioactive Dex-PAA Hydrogel Fibers

    NASA Astrophysics Data System (ADS)

    Louie, Katherine Boyook

    In this work, a novel method is developed for making nano- and micro-fibrous hydrogels capable of preventing the rejection of implanted materials. This is achieved by either (1) mimicking the native cellular environment, to exert fine control over the cellular response or (2) acting as a protective barrier, to camouflage the foreign nature of a material and evade recognition by the immune system. Comprehensive characterization and in vitro studies described here provide a foundation for developing substrates for use in clinical applications. Hydrogel dextran and poly(acrylic acid) (PAA) fibers are formed via electrospinning, in sizes ranging from nanometers to microns in diameter. While "as-electrospun" fibers are continuous in length, sonication is used to fragment fibers into short fiber "bristles" and generate nano- and micro- fibrous surface coatings over a wide range of topographies. Dex-PAA fibrous surfaces are chemically modified, and then optimized and characterized for non-fouling and ECM-mimetic properties. The non-fouling nature of fibers is verified, and cell culture studies show differential responses dependent upon chemical, topographical and mechanical properties. Dex-PAA fibers are advantageously unique in that (1) a fine degree of control is possible over three significant parameters critical for modifying cellular response: topography, chemistry and mechanical properties, over a range emulating that of native cellular environments, (2) the innate nature of the material is non-fouling, providing an inert background for adding back specific bioactive functionality, and (3) the fibers can be applied as a surface coating or comprise the scaffold itself. This is the first reported work of dex-PAA hydrogel fibers formed via electrospinning and thermal cross-linking, and unique to this method, no toxic solvents or cross-linking agents are needed to create hydrogels or for surface attachment. This is also the first reported work of using sonication to fragment electrospun hydrogel fibers, and in which surface coatings were made via simple electrostatic interaction and dehydration. These versatile features enable fibrous surface coatings to be applied to virtually any material. Results of this research broadly impact the design of biomaterials which contact cells in the body by directing the consequent cell-material interaction.

  2. Cutaneous and Labyrinthine Tolerance of Bioactive Glass S53P4 in Mastoid and Epitympanic Obliteration Surgery: Prospective Clinical Study

    PubMed Central

    Bernardeschi, Daniele; Nguyen, Yann; Russo, Francesca Yoshie; Mosnier, Isabelle; Ferrary, Evelyne; Sterkers, Olivier

    2015-01-01

    Objective. To evaluate the cutaneous and the inner ear tolerance of bioactive glass S53P4 when used in the mastoid and epitympanic obliteration for chronic otitis surgery. Material and Methods. Forty-one cases have been included in this prospective study. Cutaneous tolerance was clinically evaluated 1 week, 1 month, and 3 months after surgery with a physical examination of the retroauricular and external auditory canal (EAC) skin and the presence of otalgia; the inner ear tolerance was assessed by bone-conduction hearing threshold 1 day after surgery and by the presence of vertigo or imbalance. Results. All surgeries but 1 were uneventful: all patients maintained the preoperative bone-conduction hearing threshold except for one case in which the round window membrane was opened during the dissection of the cholesteatoma in the hypotympanum and this led to a dead ear. No dizziness or vertigo was reported. Three months after surgery, healing was achieved in all cases with a healthy painless skin. No cases of revision surgery for removal of the granules occurred in this study. Conclusion. The bioactive glass S53P4 is a well-tolerated biomaterial for primary or revision chronic otitis surgery, as shown by the local skin reaction which lasted less than 3 months and by the absence of labyrinthine complications. PMID:26504792

  3. Skin Diseases: Cross-section of human skin

    MedlinePLUS

    Skip Navigation Bar Home Current Issue Past Issues Skin Diseases Cross-section of human skin Past Issues / Fall 2008 Table of Contents For ... Logical Images, Inc. I n the areas of skin health and skin diseases, the NIH's National Institute ...

  4. Skin Care and Aging

    MedlinePLUS

    ... dry air smoking feeling stress losing sweat and oil glands (common with age). Dry skin also can be caused by health problems, such as diabetes or kidney disease. Using too much soap, antiperspirant, or perfume and taking hot baths ...

  5. Skin Care and Aging

    MedlinePLUS

    ... such as: Not drinking enough liquids Spending too much time in the sun or sun tanning Being in very dry air Smoking Feeling stress Losing sweat and oil glands, which is common with age Dry skin ...

  6. Components of skin

    MedlinePLUS Videos and Cool Tools

    ... protects the underlying skin layers from the outside environment and contains cells that make keratin, a substance ... the body to receive stimulation from the outside environment and experience pressure, pain, and temperature. Small blood ...

  7. Genetics and skin aging

    PubMed Central

    Makrantonaki, Evgenia; Bekou, Vassiliki; Zouboulis, Christos C.

    2012-01-01

    Skin aging is a complex process and underlies multiple influences with the probable involvement of heritable and various environmental factors. Several theories have been conducted regarding the pathomechanisms of aged skin, however fundamental mechanisms still remain poorly understood. This article addresses the influence of genetics on skin aging and in particular deals with the differences observed in ethnic populations and between both genders. Recent studies indicate that male and female aged skin differs as far as the type, the consistency and the sensitivity to external factors is concerned. The same has been also documented between elderly people of different origin. Consequently, the aging process taking place in both genders and in diverse ethnic groups should be examined separately and products specialized to each population should be developed in order to satisfy the special needs. PMID:23467395

  8. Skin, Hair, and Nails

    MedlinePLUS

    ... special types of cells: Melanocytes produce melanin, the pigment that gives skin its color. All people have ... the epidermis). Hair also contains a yellow-red pigment; people who have blonde or red hair have ...

  9. Skin tumors on squirrels

    USGS Publications Warehouse

    Herman, C.M.; Reilly, J.R.

    1955-01-01

    Skin tumors having the gross appearance of previously reported fibromas are reported on gray squirrels from N. Y., Md., Va., N. C., and W. Va. and from a fox squirrel from W. Va. and a porcupine from Pa.

  10. Stages of Skin Cancer

    MedlinePLUS

    ... that is not helped by lip balm or petroleum jelly . Tests or procedures that examine the skin ... and is not helped by lip balm or petroleum jelly . Treatment Option Overview Key Points There are ...

  11. Skin Cancer Treatment

    MedlinePLUS

    ... that is not helped by lip balm or petroleum jelly . Tests or procedures that examine the skin ... and is not helped by lip balm or petroleum jelly . Treatment Option Overview Key Points There are ...

  12. Skin or nail culture

    MedlinePLUS

    Mucosal culture; Culture - skin; Culture - mucosal; Nail culture; Culture - fingernail; Fingernail culture ... There, it is placed in a special dish (culture). It is then watched to see if bacteria, ...

  13. Skin Tag (Acrochordon)

    MedlinePLUS

    ... Skin Conditions References Bolognia, Jean L., ed. Dermatology , pp.1863-1864. New York: Mosby, 2003. Freedberg, Irwin ... Fitzpatrick's Dermatology in General Medicine . 6 th ed, pp. 767, 993-994, 1827. New York: McGraw-Hill, ...

  14. Skin diseases in musicians.

    PubMed

    Crépy, Marie-Noelle

    2015-10-01

    Instrumental musicians are a risk group for skin diseases. A systematic review was performed on Pubmed database and in the musical literature. Most publications on dermatoses in musicians are case reports. The exact prevalence of skin diseases in musicians is unknown but high rates have been reported. The most at-risk musicians are percussionists, string and wind instrumentalists. Repeated physical trauma is a frequent cause of skin conditions in musicians (callosities, fiddler's neck syndrome…). The allergens most often reported in musicians' allergic contact dermatitis are metals (nickel, dichromate), exotic woods and cane reed components, colophony and propolis. The key preventive measures are early management of the skin disease, specific tests and avoidance of the causative allergens, together with better adjustment of playing techniques to reduce trauma. PMID:25905552

  15. Skin manifestations in CDG.

    PubMed

    Rymen, D; Jaeken, J

    2014-09-01

    The group of congenital disorders of glycosylation (CDG) has expanded tremendously since its first description in 1980, with around 70 distinct disorders described to date. A great phenotypic variability exists, ranging from multisystem disease to single organ involvement. Skin manifestations, although inconsistently present, are part of this broad clinical spectrum. Indeed, the presence of inverted nipples, fat pads and orange peel skin in a patient with developmental delay are considered as a hallmark of CDG, particularly seen in PMM2 deficiency. However, over the years many more dermatological findings have been observed (e.g., ichthyosis, cutis laxa, tumoral calcinosis…). In this review we will discuss the variety of skin manifestations reported in CDG. Moreover, we will explore the possible mechanisms that link a certain glycosylation deficiency to its skin phenotype. PMID:24554337

  16. [Skin-picking disorder].

    PubMed

    Niemeier, V; Peters, E; Gieler, U

    2015-10-01

    The disorder is characterized by compulsive repetitive skin-picking (SP), resulting in skin lesions. The patients must have undertaken several attempts to reduce or stop SP. The disorder must have led to clinically significant limitations in social, professional, or other important areas of life. The symptoms cannot be better explained by another emotional disorder or any other dermatological disease. In the new DSM-V, skin-picking disorder has been included in the diagnostic system as an independent disorder and describes the self-injury of the skin by picking or scratching with an underlying emotional disorder. SP is classified among the impulse-control disorders and is, thus, differentiated from compulsive disorders as such. There are often emotional comorbidities. In cases of pronounced psychosocial limitation, interdisciplinary cooperation with a psychotherapist and/or psychiatrist is indicated. PMID:26391325

  17. Allergy testing - skin

    MedlinePLUS

    ... if you are allergic to bee venom or penicillin. Or it may be used if the skin ... sore, or swollen after contact with the substance Penicillin allergy Venom allergy Allergies to penicillin and closely ...

  18. Skin Cancer Prevention

    MedlinePLUS

    ... the body’s largest organ . It protects against heat, sunlight, injury, and infection . Skin also helps control body ... it is most common in areas exposed to sunlight, such as the face, neck, hands, and arms. ...

  19. Aging changes in skin

    MedlinePLUS

    ... sun exposure with areas that are protected from sunlight. Natural pigments seem to provide some protection against ... Exposures to industrial and household chemicals Indoor heating Sunlight can cause: Loss of elasticity (elastosis) Noncancerous skin ...

  20. Skin Cancer Screening

    MedlinePLUS

    ... the body's largest organ . It protects against heat, sunlight, injury, and infection . Skin also helps control body ... cancer risk factors include: Being exposed to natural sunlight or artificial sunlight (such as from tanning beds) ...

  1. Healthy Skin Matters

    MedlinePLUS

    ... don’t offer a safe alternative to natural sunlight. Exposure to ultraviolet (UV ) (uhl-truh-VYE-uh- ... the exposure comes from tanning beds or natural sunlight. This damage increases the risk of skin cancer ...

  2. Versatile module for experiments with focussing neutron guides

    SciTech Connect

    Adams, T.; Pfleiderer, C.; Böni, P.; Brandl, G.; Chacon, A.; Wagner, J. N.; Rahn, M.; Mühlbauer, S.; Georgii, R.

    2014-09-22

    We report the development of a versatile module that permits fast and reliable use of focussing neutron guides under varying scattering angles. A simple procedure for setting up the module and neutron guides is illustrated by typical intensity patterns to highlight operational aspects as well as typical parasitic artefacts. Combining a high-precision alignment table with separate housings for the neutron guides on kinematic mounts, the change-over between neutron guides with different focussing characteristics requires no readjustments of the experimental setup. Exploiting substantial gain factors, we demonstrate the performance of this versatile neutron scattering module in a study of the effects of uniaxial stress on the domain populations in the transverse spin density wave phase of single crystal Cr.

  3. Robust and versatile ionic liquid microarrays achieved by microcontact printing

    NASA Astrophysics Data System (ADS)

    Gunawan, Christian A.; Ge, Mengchen; Zhao, Chuan

    2014-04-01

    Lab-on-a-chip and miniaturized systems have gained significant popularity motivated by marked differences in material performance at the micro-to-nano-scale realm. However, to fully exploit micro-to-nano-scale chemistry, solvent volatility and lack of reproducibility need to be overcome. Here, we combine the non-volatile and versatile nature of ionic liquids with microcontact printing in an attempt to establish a facile protocol for high throughput fabrication of open microreactors and microfluidics. The micropatterned ionic liquid droplets have been demonstrated as electrochemical cells and reactors for microfabrication of metals and charge transfer complexes, substrates for immobilization of proteins and as membrane-free high-performance amperometric gas sensor arrays. The results suggest that miniaturized ionic liquid systems can be used to solve the problems of solvent volatility and slow mass transport in viscous ionic liquids in lab-on-a-chip devices, thus providing a versatile platform for a diverse number of applications.

  4. Research and development of a versatile portable speech prosthesis

    NASA Technical Reports Server (NTRS)

    1981-01-01

    The Versatile Portable Speech Prosthesis (VPSP), a synthetic speech output communication aid for non-speaking people is described. It was intended initially for severely physically limited people with cerebral palsy who are in electric wheelchairs. Hence, it was designed to be placed on a wheelchair and powered from a wheelchair battery. It can easily be separated from the wheelchair. The VPSP is versatile because it is designed to accept any means of single switch, multiple switch, or keyboard control which physically limited people have the ability to use. It is portable because it is mounted on and can go with the electric wheelchair. It is a speech prosthesis, obviously, because it speaks with a synthetic voice for people unable to speak with their own voices. Both hardware and software are described.

  5. Selected environmental skin disorders.

    PubMed

    Perpall, A

    1992-05-01

    The acute development of an irritating rash often results in a patient presenting to the Emergency Department instead of scheduling an office visit. This rash is frequently the result of the patient's interaction with the environment. Consequently, it is important that emergency physicians become more familiar with environmentally induced skin disorders. Sunburn and poison ivy are examples of these types of disorders. These and less common environmentally related skin disorders are reviewed. PMID:1559479

  6. Nicotinamide and the skin.

    PubMed

    Chen, Andrew C; Damian, Diona L

    2014-08-01

    Nicotinamide, an amide form of vitamin B3, boosts cellular energy and regulates poly-ADP-ribose-polymerase 1, an enzyme with important roles in DNA repair and the expression of inflammatory cytokines. Nicotinamide shows promise for the treatment of a wide range of dermatological conditions, including autoimmune blistering disorders, acne, rosacea, ageing skin and atopic dermatitis. In particular, recent studies have also shown it to be a potential agent for reducing actinic keratoses and preventing skin cancers. PMID:24635573

  7. [Photoaging of a skin].

    PubMed

    Galus, Ryszard; Zandecki, ?ukasz; Antiszko, Marek; Borowska, Katarzyna; Zabielski, Stanis?aw

    2007-06-01

    Photoaging is a skin aging caused by long-term exposure to the ultraviolet radiations of the sun. Ultraviolet activates activating protein-1 and generate reactive oxygen species which play a substantial role in collagen degradation. Clinically, photoaged skin appears as a coarse with deep wrinkles. Presently there are available several agents to reverse the photodamage. There is conclusive evidence that synthetic vitamin A derivatives are the most effective in the treatment of photoaging. Erythema and scaling may be experienced initially. PMID:17874634

  8. Preparation and Characterization of Bioactive Composites of Pcl/bioactive Fillers

    NASA Astrophysics Data System (ADS)

    Li, Ying; Cheah, Chi Mun; Chang, Hengky; Loh, Leonard; Kum, Adeline

    A variety of bioactive composites have been invested over the last two decades as substitute materials for diseased or damaged tissues in the human body. In this paper, bioactive composites were prepared using polycaprolactone (PCL) and hydroxyapatite (HA). The influence of micro-sized and nano-sized HA on composite properties was investigated. The nano-HA was prepared by wet chemical co-precipitation reaction method. Studies of biocomposite specimen morphology were performed by Field-emission scanning electron microscopy (SEM). XRD (X-Ray Diffraction) and DSC (Differential scanning calorimetry) were used to assess the crystal structure of HA and thermal properties of the composites, respectively. The synthesized nano-HA is found to be of high purity HA structure. The relationship between composition, structure and properties was studied. Different methods to prepare uniform composites were tried, and the outcome of this work suggests that by proper manipulation of biodegradable polymers and bioactive ceramics through material design, bioactive composites with controlled properties might be achievable.

  9. Feeding tomato and broccoli powders enriched with bioactives improves bioactivity markers in rats.

    PubMed

    Liu, Ann G; Volker, Sonja E; Jeffery, Elizabeth H; Erdman, John W

    2009-08-26

    Many studies have evaluated the cancer -preventive potential of individual bioactives from tomatoes and broccoli, but few have examined them within the context of a whole food. Male Copenhagen rats were fed diets containing 10% standard tomato powder, tomato enriched with lycopene or total carotenoids, standard broccoli floret, broccoli sprouts, or broccoli enriched with indole glucosinolates or selenium for 7 days. All broccoli diets increased the activity of colon quinone reductase (NQO1). Indole glucosinolate-enriched broccoli and selenium-enriched broccoli increased hepatic NQO1 and cytochrome P450 1A activity (P < 0.05). Standard broccoli and lycopene-enriched tomato diets down-regulated prostatic glutathione S-transferase P1 mRNA expression. Different tomato diets resulted in altered hepatic accumulation of lycopene, phytofluene, and phytoene. These results demonstrate that the bioactive content of vegetables affects both tissue content of bioactives and activity of detoxification enzymes. Enhancing bioactive content of tomatoes and broccoli may enhance efficacy in the prevention of prostate cancer. PMID:19650632

  10. Physicochemical properties and bioactivity of freeze-cast chitosan nanocomposite scaffolds reinforced with bioactive glass.

    PubMed

    Pourhaghgouy, Masoud; Zamanian, Ali; Shahrezaee, Mostafa; Masouleh, Milad Pourbaghi

    2016-01-01

    Chitosan based nanocomposite scaffolds were prepared by freeze casting method through blending constant chitosan concentration with different portions of synthesized bioactive glass nanoparticles (BGNPs). Transmission Electron Microscopy (TEM) image showed that the particles size of bioactive glass (64SiO2.28CaO.8P2O5) prepared by sol-gel method was approximately less than 20 nm. Fourier Transform Infrared Spectroscopy (FT-IR) and X-ray Diffraction (XRD) analysis showed proper interfacial bonding between BGNPs and chitosan polymers. Scanning Electron Microscopy (SEM) images depicted a unidirectional structure with homogenous distribution of BGNPs among chitosan matrix associated with the absence of pure chitosan scaffold's wall pores after addition of only 10 wt.% BGNPs. As the BGNP content increased from 0 to 50 wt.%, the compressive strength and compressive module values increased from 0.034 to 0.419 MPa and 0.41 to 10.77 MPa, respectively. Biodegradation study showed that increase in BGNP content leads to growth of weight loss amount. The in vitro biomineralization studies confirmed the bioactive nature of all nanocomposites. Amount of 30 wt.% BGNPs represented the best concentration for absorption capacity and bioactivity behaviors. PMID:26478301

  11. Influence of barium substitution on bioactivity, thermal and physico-mechanical properties of bioactive glass.

    PubMed

    Arepalli, Sampath Kumar; Tripathi, Himanshu; Vyas, Vikash Kumar; Jain, Shubham; Suman, Shyam Kumar; Pyare, Ram; Singh, S P

    2015-04-01

    Barium with low concentration in the glasses acts as a muscle stimulant and is found in human teeth. We have made a primary study by substituting barium in the bioactive glass. The chemical composition containing (46.1-X) SiO2--24.3 Na2O-26.9 CaO-2.6 P2O5, where X=0, 0.4, 0.8, 1.2 and 1.6mol% of BaO was chosen and melted in an electric furnace at 14005C. The glasses were characterized to determine their use in biomedical applications. The nucleation and crystallization regimes were determined by DTA and the controlled crystallization was carried out by suitable heat treatment. The crystalline phase formed was identified by using XRD technique. Bioactivity of these glasses was assessed by immersion in simulated body fluid (SBF) for various time periods. The formation of hydroxy carbonate apatite (HCA) layer was identified by FTIR spectrometry, scanning electron microscope (SEM) and XRD which showed the presence of HCA as the main phase in all tested bioactive glass samples. Flexural strength and densities of bioactive glasses have been measured and found to increase with increasing the barium content. The human blood compatibility of the samples was evaluated and found to be pertinent. PMID:25686983

  12. Versatile composite resins simplifying the practice of restorative dentistry.

    PubMed

    Margeas, Robert

    2014-01-01

    After decades of technical development and refinement, composite resins continue to simplify the practice of restorative dentistry, offering clinicians versatility, predictability, and enhanced physical properties. With a wide range of products available today, composite resins are a reliable, conservative, multi-functional restorative material option. As manufacturers strive to improve such properties as compression strength, flexural strength, elastic modulus, coefficient of thermal expansion, water sorption, and wear resistance, several classification systems of composite resins have been developed. PMID:24571527

  13. A Versatile Method for Grafting Polymers on Nanoparticles

    PubMed Central

    Gann, John P.; Yan, Mingdi

    2015-01-01

    We report a simple and versatile method for grafting polymers on nanoparticles. A procedure was developed for the synthesis and subsequent functionalization of silica nanoparticles with a perfluorophenylazide. Polymers were then grafted by the photochemically induced insertion reactions of the perfluorophenylnitrene. Polystyrene, poly(4-vinylpyridine), and poly(2-ethyl-2-oxazoline) were successfully grafted on silica nanoparticles. Grafting density was studied with regard to polymer concentration and molecular weight. PMID:18433181

  14. A Versatile X-Ray Topographic Camera with Elastic Translation

    NASA Astrophysics Data System (ADS)

    Hnnicke, Marcelo Goncalves; Mazzaro, Irineu; Cusatis, Cesar; Etgens, Victor Hugo

    2004-08-01

    A versatile X-ray topographic Lang camera was developed and tested. A simple and easy-to-build elastic system driven by a stepping motor is used to avoid expensive and sophisticated bearings normally required for highly precise translation. After initial and permanent corrections for repetitive angular deviation (yaw), the angular stability was 10 ?rad for a 30 mm translation during a 16 h run. Topographical images taken with this camera show that it is a reliable and thermomechanically stable apparatus.

  15. Pregnancy and Skin

    PubMed Central

    Vora, Rita V.; Gupta, Rajat; Mehta, Malay J.; Chaudhari, Arvind H.; Pilani, Abhishek P.; Patel, Nidhi

    2014-01-01

    Pregnancy is associated with complex of endocrinological, immunological, metabolic, and vascular changes that may influence the skin and other organs in various ways. Pregnancy is a period in which more than 90% women have significant and complex skin changes that may have great impact on the woman's life. The dermatoses of pregnancy represent a heterogeneous group of skin diseases related to pregnancy and/or the postpartum period. The dermatoses of pregnancy can be classified into the following three groups: Physiologic skin changes in pregnancy, pre-existing dermatoses affected by pregnancy, and specific dermatoses of pregnancy. Though most of these skin dermatoses are benign and resolve in postpartum period, a few can risk fetal life and require antenatal surveillance. Most of the dermatoses of pregnancy can be treated conservatively but a few require intervention in the form of termination of pregnancy. Correct diagnosis is essential for the treatment of these disorders. This article discusses the current knowledge of various skin changes during pregnancy and the evaluation of the patient with pregnancy dermatoses with special emphasis on clinical features, diagnostic tests, maternal and fetal prognosis, therapy, and management. PMID:25657937

  16. Pregnancy and skin.

    PubMed

    Vora, Rita V; Gupta, Rajat; Mehta, Malay J; Chaudhari, Arvind H; Pilani, Abhishek P; Patel, Nidhi

    2014-01-01

    Pregnancy is associated with complex of endocrinological, immunological, metabolic, and vascular changes that may influence the skin and other organs in various ways. Pregnancy is a period in which more than 90% women have significant and complex skin changes that may have great impact on the woman's life. The dermatoses of pregnancy represent a heterogeneous group of skin diseases related to pregnancy and/or the postpartum period. The dermatoses of pregnancy can be classified into the following three groups: Physiologic skin changes in pregnancy, pre-existing dermatoses affected by pregnancy, and specific dermatoses of pregnancy. Though most of these skin dermatoses are benign and resolve in postpartum period, a few can risk fetal life and require antenatal surveillance. Most of the dermatoses of pregnancy can be treated conservatively but a few require intervention in the form of termination of pregnancy. Correct diagnosis is essential for the treatment of these disorders. This article discusses the current knowledge of various skin changes during pregnancy and the evaluation of the patient with pregnancy dermatoses with special emphasis on clinical features, diagnostic tests, maternal and fetal prognosis, therapy, and management. PMID:25657937

  17. Skin pigmentation enhancers.

    PubMed

    Brown, D A

    2001-10-01

    The highest incidences of cancer are found in the skin, but endogenous pigmentation is associated with markedly reduced risk. Agents that enhance skin pigmentation have the potential to reduce both photodamage and skin cancer incidence. The purpose of this review is to evaluate agents that have the potential to increase skin pigmentation. These include topically applied substances that simulate natural pigmentation: dihydroxyacetone and melanins; and substances that stimulate the natural pigmentation process: psoralens with UVA (PUVA), dimethylsulfoxide (DMSO), L-tyrosine, L-Dopa, lysosomotropic agents, diacylglycerols, thymidine dinucleotides, DNA fragments, melanocyte stimulating hormone (MSH) analogs, 3-isobutyl-1-methylxanthine (IBMX), nitric oxide donors, and bicyclic monoterpene (BMT) diols. These agents are compared with regards to efficacy when administered to melanoma cells, normal human epidermal melanocytes, animal skin, and human skin. In addition, mechanisms of action are reviewed since these may reveal issues related to both efficacy and safety. Both dihydroxyacetone and topically applied melanins are presently available to the consumer, and both of these have been shown to provide some photoprotection. Of the pigmentation stimulators, only PUVA and MSH analogs have been tested extensively on humans, but there are concerns about the safety and side effects of both. At least some of the remaining pigmentation stimulators under development have the potential to safely induce a photoprotective tan. PMID:11684462

  18. Effect of nitrogen and fluorine on mechanical properties and bioactivity in two series of bioactive glasses.

    PubMed

    Bachar, Ahmed; Mercier, Cyrille; Tricoteaux, Arnaud; Hampshire, Stuart; Leriche, Anne; Follet, Claudine

    2013-07-01

    Bioactive glasses are able to bond to bone through formation of carbonated hydroxyapatite in body fluids, and fluoride-releasing bioactive glasses are of interest for both orthopaedic and, in particular, dental applications for caries inhibition. However, because of their poor strength their use is restricted to non-load-bearing applications. In order to increase their mechanical properties, doping with nitrogen has been performed on two series of bioactive glasses: series (I) was a "bioglass" composition (without P2O5) within the quaternary system SiO2-Na2O-CaO-Si3N4 and series (II) was a simple substitution of CaF2 for CaO in series (I) glasses keeping the Na:Ca ratio constant. The objective of this work was to evaluate the effect of the variation in nitrogen and fluorine content on the properties of these glasses. The density, glass transition temperature, hardness and elastic modulus all increased linearly with nitrogen content which indicates that the incorporation of nitrogen stiffens the glass network because N is mainly in 3-fold coordination with Si atoms. Fluorine addition significantly decreases the thermal property values but the mechanical properties of these glasses remain unchanged with fluorine. The combination of both nitrogen and fluorine in oxyfluoronitride glasses gives better mechanical properties at much lower melting temperatures since fluorine reduces the melting point, allows higher solubility of nitrogen and does not affect the higher mechanical properties arising from incorporation of nitrogen. The characterization of these N and F substituted bioactive glasses using (29)Si MAS NMR has shown that the increase in rigidity of the glass network can be explained by the formation of SiO3N, SiO2N2 tetrahedra and Q(4) units with extra bridging anions at the expense of Q(3) units. Bioactivity of the glasses was investigated in vitro by examining apatite formation on the surface of glasses treated in acellular simulated body fluid (SBF) with ion concentrations similar to those in human blood plasma. Formation of a bioactive apatite layer on the samples treated in SBF was confirmed by grazing incidence X-ray diffraction and scanning electron microscopy (SEM) combined with energy dispersive X-ray spectroscopy (EDS). The crystallinity of this layer decreases with increasing N content suggesting that N may decrease bioactivity slightly. PMID:23676624

  19. Marine Nucleosides: Structure, Bioactivity, Synthesis and Biosynthesis

    PubMed Central

    Huang, Ri-Ming; Chen, Yin-Ning; Zeng, Ziyu; Gao, Cheng-Hai; Su, Xiangdong; Peng, Yan

    2014-01-01

    Nucleosides are glycosylamines that structurally form part of nucleotide molecules, the building block of DNA and RNA. Both nucleosides and nucleotides are vital components of all living cells and involved in several key biological processes. Some of these nucleosides have been obtained from a variety of marine resources. Because of the biological importance of these compounds, this review covers 68 marine originated nucleosides and their synthetic analogs published up to June 2014. The review will focus on the structures, bioactivities, synthesis and biosynthetic processes of these compounds. PMID:25474189

  20. Human milk composition: nutrients and bioactive factors.

    PubMed

    Ballard, Olivia; Morrow, Ardythe L

    2013-02-01

    This article provides an overview of the composition of human milk, its variation, and its clinical relevance. The composition of human milk is the biological norm for infant nutrition. Human milk also contains many hundreds to thousands of distinct bioactive molecules that protect against infection and inflammation and contribute to immune maturation, organ development, and healthy microbial colonization. Some of these molecules (eg, lactoferrin) are being investigated as novel therapeutic agents. Human milk changes in composition from colostrum to late lactation, within feeds, by gestational age, diurnally, and between mothers. Feeding infants with expressed human milk is increasing. PMID:23178060

  1. A Combinatorial Auction among Versatile Experts and Amateurs

    NASA Astrophysics Data System (ADS)

    Ito, Takayuki; Yokoo, Makoto; Matsubara, Shigeo

    Auctions have become an integral part of electronic commerce and a promising field for applying multi-agent technologies. Correctly judging the quality of auctioned goods is often difficult for amateurs, in particular, in Internet auctions. However, experts can correctly judge the quality of goods. In this situation, it is difficult to make experts tell the truth and attain an efficient allocation, since experts have a clear advantage over amateurs and they would not reveal their valuable information without some reward. In our previous work, we have succeeded in developing such auction protocols under the following two cases: (1) the case of a single-unit auction among experts and amateurs, and (2) the case of a combinatorial auction among single-skilled experts and amateurs. In this paper, we focus on versatile experts. Versatile experts have an interest in, and expert knowledge on the qualities of several goods. In the case of versatile experts, there would be several problems, e.g., free riding problems, if we simply extended the previous VCG-style auction protocol. Thus, in this paper, we employ PORF (price-oriented, rationing-free) protocol for designing our new protocol to realize a strategy-proof auction protocol for experts. In the protocol, the dominant strategy for experts is truth-telling. Also, for amateurs, truth-telling is the best response when two or more experts select the dominant strategy. Furthermore, the protocol is false-name-proof.

  2. Reconstructive versatility of the pectoralis major myocutaneous flap.

    PubMed

    Strelzow, V V; Finseth, F; Fee, W E

    1980-01-01

    The pectoralis major myocutaneous flap is presented in its two basic forms: a muscle flap carrying a skin paddle and the continuous skin-muscle flap technique. The pertinent anatomy of the enveloping fascial planes is reviewed, stressing the increased latitude of safety afforded by elevating the vascular pedicle from the undersurface of the lateral muscle edge. The advantages of a deltopectoral flap outline in approaching the formation of the skin-muscle paddle are introduced. Clinical applications, advantages, and disadvantages are discussed. PMID:6821417

  3. Composite bone cements loaded with a bioactive and ferrimagnetic glass-ceramic: Leaching, bioactivity and cytocompatibility.

    PubMed

    Verné, Enrica; Bruno, Matteo; Miola, Marta; Maina, Giovanni; Bianco, Carlotta; Cochis, Andrea; Rimondini, Lia

    2015-08-01

    In this work, composite bone cements, based on a commercial polymethylmethacrylate matrix (Palamed®) loaded with ferrimagnetic bioactive glass-ceramic particles (SC45), were produced and characterized in vitro. The ferrimagnetic bioactive glass-ceramic belongs to the system SiO2-Na2O-CaO-P2O5-FeO-Fe2O3 and contains magnetite (Fe3O4) crystals into a residual amorphous bioactive phase. Three different formulations (containing 10, 15 and 20 wt.% of glass-ceramic particles respectively) have been investigated. These materials are intended to be applied as bone fillers for the hyperthermic treatment of bone tumors. The morphological, compositional, calorimetric and mechanical properties of each formulation have been already discussed in a previous paper. The in vitro properties of the composite bone cements described in the present paper are related to iron ion leaching test (by graphite furnace atomic absorption spectrometer), bioactivity (i.e. the ability to stimulate the formation of a hydroxyapatite - HAp - layer on their surface after soaking in simulated body fluid SBF) and cytocompatibility toward human osteosarcoma cells (ATCC CRL-1427, Mg63). Morphological and chemical characterizations by scanning electron microscopy and energy dispersion spectrometry have been performed on the composite samples after each test. The iron release was negligible and all the tested samples showed the growth of HAp on their surface after 28 days of immersion in a simulated body fluid (SBF). Cells showed good viability, morphology, adhesion, density and the ability to develop bridge-like structures on all investigated samples. A synergistic effect between bioactivity and cell mineralization was also evidenced. PMID:26042695

  4. Thyroid hormone action on skin

    PubMed Central

    2011-01-01

    The skin characteristics associated with thyroid hormone are classic. The name myxedema refers to the associated skin condition caused by increased glycosaminoglycan deposition in the skin. Generalized myxedema is still the classic cutaneous sign of hypothyroidism. It is caused by deposition of dermal acid mucopolysaccharides, notably hyaluronic acid. Despite its appearance, the skin does not pit with pressure. PMID:22110782

  5. What Causes Our Skin to Age?

    MedlinePLUS

    ... skin What causes aging skin What causes our skin to age? Sun protection essential: Dermatologists agree that ... on our skin. 11 ways to reduce premature skin aging The sun plays a major role in ...

  6. Bioavailability of bioactive food compounds: a challenging journey to bioefficacy.

    PubMed

    Rein, Maarit J; Renouf, Mathieu; Cruz-Hernandez, Cristina; Actis-Goretta, Lucas; Thakkar, Sagar K; da Silva Pinto, Marcia

    2013-03-01

    Bioavailability is a key step in ensuring bioefficacy of bioactive food compounds or oral drugs. Bioavailability is a complex process involving several different stages: liberation, absorption, distribution, metabolism and elimination phases (LADME). Bioactive food compounds, whether derived from various plant or animal sources, need to be bioavailable in order to exert any beneficial effects. Through a better understanding of the digestive fate of bioactive food compounds we can impact the promotion of health and improvement of performance. Many varying factors affect bioavailability, such as bioaccessibility, food matrix effect, transporters, molecular structures and metabolizing enzymes. Bioefficacy may be improved through enhanced bioavailability. Therefore, several technologies have been developed to improve the bioavailability of xenobiotics, including structural modifications, nanotechnology and colloidal systems. Due to the complex nature of food bioactive compounds and also to the different mechanisms of absorption of hydrophilic and lipophilic bioactive compounds, unravelling the bioavailability of food constituents is challenging. Among the food sources discussed during this review, coffee, tea, citrus fruit and fish oil were included as sources of food bioactive compounds (e.g. (poly)phenols and polyunsaturated fatty acids (PUFAs)) since they are examples of important ingredients for the food industry. Although there are many studies reporting on bioavailability and bioefficacy of these bioactive food components, understanding their interactions, metabolism and mechanism of action still requires extensive work. This review focuses on some of the major factors affecting the bioavailability of the aforementioned bioactive food compounds. PMID:22897361

  7. Effects of milk-derived bioactives: an overview.

    PubMed

    Shah, N P

    2000-11-01

    Milk contains various components with physiological functionality. Peptides derived from caseins and whey proteins including opioid peptides, antihypertensive peptides, casein phosphopeptides, alpha- and beta-lactorphins and albutensin have been shown to possess various bioactive properties. This review considers an overview of the bioactive components in milk proteins and whey and their physiological function. PMID:11242440

  8. Bioavailability of bioactive food compounds: a challenging journey to bioefficacy

    PubMed Central

    Rein, Maarit J.; Renouf, Mathieu; Cruz‐Hernandez, Cristina; Actis‐Goretta, Lucas; Thakkar, Sagar K.; da Silva Pinto, Marcia

    2013-01-01

    Bioavailability is a key step in ensuring bioefficacy of bioactive food compounds or oral drugs. Bioavailability is a complex process involving several different stages: liberation, absorption, distribution, metabolism and elimination phases (LADME). Bioactive food compounds, whether derived from various plant or animal sources, need to be bioavailable in order to exert any beneficial effects. Through a better understanding of the digestive fate of bioactive food compounds we can impact the promotion of health and improvement of performance. Many varying factors affect bioavailability, such as bioaccessibility, food matrix effect, transporters, molecular structures and metabolizing enzymes. Bioefficacy may be improved through enhanced bioavailability. Therefore, several technologies have been developed to improve the bioavailability of xenobiotics, including structural modifications, nanotechnology and colloidal systems. Due to the complex nature of food bioactive compounds and also to the different mechanisms of absorption of hydrophilic and lipophilic bioactive compounds, unravelling the bioavailability of food constituents is challenging. Among the food sources discussed during this review, coffee, tea, citrus fruit and fish oil were included as sources of food bioactive compounds (e.g. (poly)phenols and polyunsaturated fatty acids (PUFAs)) since they are examples of important ingredients for the food industry. Although there are many studies reporting on bioavailability and bioefficacy of these bioactive food components, understanding their interactions, metabolism and mechanism of action still requires extensive work. This review focuses on some of the major factors affecting the bioavailability of the aforementioned bioactive food compounds. PMID:22897361

  9. PHARMACOLOGICAL ASSESSMENT OF HISPIDULIN--A NATURAL BIOACTIVE FLAVONE.

    PubMed

    Atif, Muhammad; Ali, Iftikhar; Hussain, Ajaz; Hyder, Syed Viqar; Niaz, Basit; Khan, Farhan Ahmed; Maalik, Aneela; Farooq, Umar

    2015-01-01

    Hispidulin is well-known natural bioactive flavone on behalf of its pharmacological aspects. This review contains data on isolation, synthetic methodology, pharmacokinetics and bioactivities of hispidulin. The article provides a critical assessment of present knowledge about hispidulin with some clear conclusions, perspectives and directions for future research in potential applications. PMID:26665389

  10. Bioactivity, toxicity and dissipation of hexaconazole enantiomers.

    PubMed

    Han, Jiajun; Jiang, Jiazhen; Su, Hang; Sun, Mingjing; Wang, Peng; Liu, Donghui; Zhou, Zhiqiang

    2013-11-01

    In this study, the bioactivity, acute toxicity and dissipation in vegetables of the individual enantiomers of the fungicide hexaconazole had been investigated. The optical pure single enantiomers were prepared and the bioactivity of (+)-, (-)- and rac-hexaconazole was tested using four target fungi including Colletotrichum gloeosporioides Penz, Alternaria solani, Alternaria mali Roberts and Monilinia fructicola. The results showed (-)-hexaconazole was always more active than (+)-hexaconazole with the fungicidal activity 1113-fold higher to A. solani, A. mali Roberts and Monilinia fructicola, and 1.26-fold higher to C. gloeosporioides Penz. (-)-Hexaconazole also showed 1.3-fold higher acute toxicity to aquatic species Daphnia magna based on the 48 h EC50 values. There was obvious enantioselectivity in the dissipation in tomato with (-)-hexaconazole degraded faster resulting an enrichment of (+)-form, and the half-lives of (-)-hexaconazole and (+)-hexaconazole in tomato were 2.96 d and 3.38 d respectively, while it was not enantioselective in green pepper, in which the both enantiomers had the half-lives about 4.36 d. The findings are helpful for better environmental and ecological risk assessment of hexaconazole on an enantiomeric level. PMID:24206830

  11. Processing of apple pomace for bioactive molecules.

    PubMed

    Bhushan, Shashi; Kalia, Kalpana; Sharma, Madhu; Singh, Bikram; Ahuja, P S

    2008-01-01

    The growth of horticulture industries worldwide has generated huge quantities of fruit wastes (25%-40% of the total fruits processed). These residues are generally a good source of carbohydrates, especially cell wall polysaccharides and other functionally important bioactive molecules such as proteins, vitamins, minerals and natural antioxidants. "Apple pomace" is a left-over solid biomass with a high moisture content, obtained as a by-product during the processing of apple fruits for juice, cider or wine preparation. Owing to the high carbohydrate content, apple pomace is used as a substrate in a number of microbial processes for the production of organic acids, enzymes, single cell protein, ethanol, low alcoholic drinks and pigments. Recent research trends reveal that there is an increase in the utilization of apple pomace as a food processing residue for the extraction of value added products such as dietary fibre, protein, natural antioxidants, biopolymers, pigments and compounds with unique properties. However, the central dogma is still the stability, safety and economic feasibility of the process(s)/product(s) developed. This review is mainly focused on assessing recent research developments in extraction, isolation and characterization of bioactive molecules from apple pomace, along with their commercial utilization, in food fortification. PMID:19051107

  12. Mechanisms of human erythrocytic bioactivation of nitrite.

    PubMed

    Liu, Chen; Wajih, Nadeem; Liu, Xiaohua; Basu, Swati; Janes, John; Marvel, Madison; Keggi, Christian; Helms, Christine C; Lee, Amber N; Belanger, Andrea M; Diz, Debra I; Laurienti, Paul J; Caudell, David L; Wang, Jun; Gladwin, Mark T; Kim-Shapiro, Daniel B

    2015-01-01

    Nitrite signaling likely occurs through its reduction to nitric oxide (NO). Several reports support a role of erythrocytes and hemoglobin in nitrite reduction, but this remains controversial, and alternative reductive pathways have been proposed. In this work we determined whether the primary human erythrocytic nitrite reductase is hemoglobin as opposed to other erythrocytic proteins that have been suggested to be the major source of nitrite reduction. We employed several different assays to determine NO production from nitrite in erythrocytes including electron paramagnetic resonance detection of nitrosyl hemoglobin, chemiluminescent detection of NO, and inhibition of platelet activation and aggregation. Our studies show that NO is formed by red blood cells and inhibits platelet activation. Nitric oxide formation and signaling can be recapitulated with isolated deoxyhemoglobin. Importantly, there is limited NO production from erythrocytic xanthine oxidoreductase and nitric-oxide synthase. Under certain conditions we find dorzolamide (an inhibitor of carbonic anhydrase) results in diminished nitrite bioactivation, but the role of carbonic anhydrase is abrogated when physiological concentrations of CO2 are present. Importantly, carbon monoxide, which inhibits hemoglobin function as a nitrite reductase, abolishes nitrite bioactivation. Overall our data suggest that deoxyhemoglobin is the primary erythrocytic nitrite reductase operating under physiological conditions and accounts for nitrite-mediated NO signaling in blood. PMID:25471374

  13. Bioactivation of biomorphous silicon carbide bone implants.

    PubMed

    Will, Julia; Hoppe, Alexander; Mller, Frank A; Raya, Carmen T; Fernndez, Julin M; Greil, Peter

    2010-12-01

    Wood-derived silicon carbide (SiC) offers a specific biomorphous microstructure similar to the cellular pore microstructure of bone. Compared with bioactive ceramics such as calcium phosphate, however, silicon carbide is considered not to induce spontaneous interface bonding to living bone. Bioactivation by chemical treatment of biomorphous silicon carbide was investigated in order to accelerate osseointegration and improve bone bonding ability. Biomorphous SiC was processed from sipo (Entrandrophragma utile) wood by heating in an inert atmosphere and infiltrating the resulting carbon replica with liquid silicon melt at 1450C. After removing excess silicon by leaching in HF/HNO? the biomorphous preform consisted of ?-SiC with a small amount (approximately 6wt.%) of unreacted carbon. The preform was again leached in HCl/HNO? and finally exposed to CaCl? solution. X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared analyses proved that oxidation of the residual carbon at the surface induced formation of carboxyl [COO?] groups, which triggered adsorption of Ca(2+), as confirmed by XPS and inductively coupled plasma optical emission spectroscopy measurements. A local increase in Ca(2+) concentration stimulated in vitro precipitation of Ca?(PO?)?OH (HAP) on the silicon carbide preform surface during exposure to simulated body fluid, which indicates a significantly increased bone bonding activity compared with SiC. PMID:20615484

  14. Discovering new bioactive molecules from microbial sources

    PubMed Central

    Monciardini, Paolo; Iorio, Marianna; Maffioli, Sonia; Sosio, Margherita; Donadio, Stefano

    2014-01-01

    There is an increased need for new drug leads to treat diseases in humans, animals and plants. A dramatic example is represented by the need for novel and more effective antibiotics to combat multidrug-resistant microbial pathogens. Natural products represent a major source of approved drugs and still play an important role in supplying chemical diversity, despite a decreased interest by large pharmaceutical companies. Novel approaches must be implemented to decrease the chances of rediscovering the tens of thousands of known natural products. In this review, we present an overview of natural product screening, focusing particularly on microbial products. Different approaches can be implemented to increase the probability of finding new bioactive molecules. We thus present the rationale and selected examples of the use of hypersensitive assays; of accessing unexplored microorganisms, including the metagenome; and of genome mining. We then focus our attention on the technology platform that we are currently using, consisting of approximately 70?000 microbial strains, mostly actinomycetes and filamentous fungi, and discuss about high-quality screening in the search for bioactive molecules. Finally, two case studies are discussed, including the spark that arose interest in the compound: in the case of orthoformimycin, the novel mechanism of action predicted a novel structural class; in the case of NAI-112, structural similarity pointed out to a possible in vivo activity. Both predictions were then experimentally confirmed. PMID:24661414

  15. Bioactive Glass for Large Bone Repair.

    PubMed

    Jia, Weitao; Lau, Grace Y; Huang, Wenhai; Zhang, Changqing; Tomsia, Antoni P; Fu, Qiang

    2015-12-01

    There has been an ongoing quest for new biomedical materials for the repair and regeneration of large segmental bone defects caused by disease or trauma. Autologous bone graft (ABG) remains the gold standard for bone repair despite their limited supply and donor-site morbidity. The current tissue engineering approach with synthetically derived bone grafts requires a bioactive ceramic or polymeric scaffold loaded with growth factors for osteoinduction and angiogenesis, and bone marrow stromal cells (BMSCs) for osteogenic properties. Unfortunately, this approach has serious drawbacks: the low mechanical strength of scaffolds, the high cost of growth factors, and a lack of optimal strategies for growth-factor delivery. Here, it is shown that, for the first time, a synthetic material alone can repair large bone defects as efficiently as the gold standard ABG. Through the use of strong and resorbable bioactive glass scaffolds, complete bone healing, and defect bridging can be achieved in a rabbit femur segmental defect model without growth factors or BMSCs. New bone and blood vessel formation, in both inner and peripheral scaffolds, demonstrates the excellent osteoinductive and osteogenic properties of these scaffolds similar as ABG. PMID:26582584

  16. Discovering new bioactive molecules from microbial sources.

    PubMed

    Monciardini, Paolo; Iorio, Marianna; Maffioli, Sonia; Sosio, Margherita; Donadio, Stefano

    2014-05-01

    There is an increased need for new drug leads to treat diseases in humans, animals and plants. A dramatic example is represented by the need for novel and more effective antibiotics to combat multidrug-resistant microbial pathogens. Natural products represent a major source of approved drugs and still play an important role in supplying chemical diversity, despite a decreased interest by large pharmaceutical companies. Novel approaches must be implemented to decrease the chances of rediscovering the tens of thousands of known natural products. In this review, we present an overview of natural product screening, focusing particularly on microbial products. Different approaches can be implemented to increase the probability of finding new bioactive molecules. We thus present the rationale and selected examples of the use of hypersensitive assays; of accessing unexplored microorganisms, including the metagenome; and of genome mining. We then focus our attention on the technology platform that we are currently using, consisting of approximately 70,000 microbial strains, mostly actinomycetes and filamentous fungi, and discuss about high-quality screening in the search for bioactive molecules. Finally, two case studies are discussed, including the spark that arose interest in the compound: in the case of orthoformimycin, the novel mechanism of action predicted a novel structural class; in the case of NAI-112, structural similarity pointed out to a possible in vivo activity. Both predictions were then experimentally confirmed. PMID:24661414

  17. Angiogenesis stimulated by novel nanoscale bioactive glasses.

    PubMed

    Mao, Cong; Chen, Xiaofeng; Miao, Guohou; Lin, Cai

    2015-04-01

    The ability of biomaterials to induce rapid vascular formation is critical in tissue regeneration. Combining recombinant angiogenic growth factors with bioengineered constructs have proven to be difficult due to several issues, including the instability of recombinant proteins, the need for sustained delivery and the dosage of factors. New formulations of bioactive glass, 58S nanosized bioactive glass (58S-NBG), have been reported to enhance wound healing in animal models better than the first generation of 45S5 Bioglass. Therefore, we investigated the effects of extracts of 58S-NBG and 80S-NBG on cultures of human umbilical vein endothelial cells (HUVECs). Cell viability was assessed by MTS assay. In vitro angiogenesis was measured using an ECM gel tube formation assay, and levels of mRNAs for five angiogenic related genes were measured by qRT-PCR. Extracts of 58S-NBG and 80S-NBG stimulated the proliferation of HUVECs, accelerated cell migration, up-regulated expression of the vascular endothelial growth factor, basic fibroblast growth factor, their receptors, and endothelial nitric oxide synthase, resulting in enhanced tube formation in vitro. The enhanced angiogenic response correlated with increased levels of Ca and Si in the extracts of 58S-NBG and 80S-NBG. The ability of 58S-NBG and 80S-NBG to stimulate angiogenesis in vitro provides alternative approaches for stimulating neovascularization of tissue-engineered constructs. PMID:25805509

  18. Micropatterning of bioactive self-assembling gels

    PubMed Central

    Mata, Alvaro; Hsu, Lorraine; Capito, Ramille; Aparicio, Conrado; Henrikson, Karl

    2009-01-01

    Microscale topographical features have been known to affect cell behavior. An important target in this area is to integrate top down techniques with bottom up self-assembly to create three-dimensional (3D) patterned bioactive mimics of extracellular matrices. We report a novel approach toward this goal and demonstrate its use to study the behavior of human mesenchymal stem cells (hMSCs). By incorporating polymerizable acetylene groups in the hydrophobic segment of peptide amphiphiles (PAs), we were able to micro-pattern nanofiber gels of these bioactive materials. PAs containing the cell adhesive epitope arginineglycineaspartic acidserine (RGDS) were allowed to self-assemble within microfabricated molds to create networks of either randomly oriented or aligned ~30 nm diameter nanofiber bundles that were shaped into topographical patterns containing holes, posts, or channels up to 8 ?m in height and down to 5 ?m in lateral dimensions. When topographical patterns contained nanofibers aligned through flow prior to gelation, the majority of hMSCs aligned in the direction of the nanofibers even in the presence of hole microtextures and more than a third of them maintained this alignment when encountering perpendicular channel microtextures. Interestingly, in topographical patterns with randomly oriented nanofibers, osteoblastic differentiation was enhanced on hole microtextures compared to all other surfaces. PMID:20047022

  19. Mechanisms of Human Erythrocytic Bioactivation of Nitrite*

    PubMed Central

    Liu, Chen; Wajih, Nadeem; Liu, Xiaohua; Basu, Swati; Janes, John; Marvel, Madison; Keggi, Christian; Helms, Christine C.; Lee, Amber N.; Belanger, Andrea M.; Diz, Debra I.; Laurienti, Paul J.; Caudell, David L.; Wang, Jun; Gladwin, Mark T.; Kim-Shapiro, Daniel B.

    2015-01-01

    Nitrite signaling likely occurs through its reduction to nitric oxide (NO). Several reports support a role of erythrocytes and hemoglobin in nitrite reduction, but this remains controversial, and alternative reductive pathways have been proposed. In this work we determined whether the primary human erythrocytic nitrite reductase is hemoglobin as opposed to other erythrocytic proteins that have been suggested to be the major source of nitrite reduction. We employed several different assays to determine NO production from nitrite in erythrocytes including electron paramagnetic resonance detection of nitrosyl hemoglobin, chemiluminescent detection of NO, and inhibition of platelet activation and aggregation. Our studies show that NO is formed by red blood cells and inhibits platelet activation. Nitric oxide formation and signaling can be recapitulated with isolated deoxyhemoglobin. Importantly, there is limited NO production from erythrocytic xanthine oxidoreductase and nitric-oxide synthase. Under certain conditions we find dorzolamide (an inhibitor of carbonic anhydrase) results in diminished nitrite bioactivation, but the role of carbonic anhydrase is abrogated when physiological concentrations of CO2 are present. Importantly, carbon monoxide, which inhibits hemoglobin function as a nitrite reductase, abolishes nitrite bioactivation. Overall our data suggest that deoxyhemoglobin is the primary erythrocytic nitrite reductase operating under physiological conditions and accounts for nitrite-mediated NO signaling in blood. PMID:25471374

  20. Versatile new ion source for the analysis of materials in open air under ambient conditions.

    PubMed

    Cody, Robert B; Larame, James A; Durst, H Dupont

    2005-04-15

    A new ion source has been developed for rapid, noncontact analysis of materials at ambient pressure and at ground potential. The new source, termed DART (for "Direct Analysis in Real Time"), is based on the reactions of electronic or vibronic excited-state species with reagent molecules and polar or nonpolar analytes. DART has been installed on a high-resolution time-of-flight mass spectrometer (TOFMS) that provides improved selectivity and accurate elemental composition assignment through exact mass measurements. Although DART has been applied to the analysis of gases, liquids, and solids, a unique application is the direct detection of chemicals on surfaces without requiring sample preparation, such as wiping or solvent extraction. DART has demonstrated success in sampling hundreds of chemicals, including chemical agents and their signatures, pharmaceutics, metabolites, peptides and oligosaccharides, synthetic organics, organometallics, drugs of abuse, explosives, and toxic industrial chemicals. These species were detected on various surfaces, such as concrete, asphalt, human skin, currency, airline boarding passes, business cards, fruits, vegetables, spices, beverages, body fluids, horticultural leaves, cocktail glasses, and clothing. DART employs no radioactive components and is more versatile than devices using radioisotope-based ionization. Because its response is instantaneous, DART provides real-time information, a critical requirement for screening or high throughput. PMID:15828760

  1. Elastin fibers display a versatile microfibril network in articular cartilage depending on the mechanical microenvironments.

    PubMed

    He, Bo; Wu, Jian Ping; Chen, Hong Hui; Kirk, Thomas Brett; Xu, Jiake

    2013-09-01

    Elastin fibers are major extracellular matrix macromolecules that are critical in maintaining the elasticity and resilience of tissues such as blood vessels, lungs and skins. However, the role of elastin in articular cartilage is poorly defined. The present study investigated the organization of elastin fiber in articular cartilage, its relationship to collagen fibers and the architecture of elastin fibers from different mechanical environments by using a kangaroo model. Five morphologies of elastin fibers were identified: Straight fiber, straight fiber with branches, branching fibers directly associated with chondrocyte, wave fiber and fine elastin. The architecture of the elastin network varied significantly with cartilage depth. In the most superficial layer of tibial plateau articular cartilage, dense elastin fibers formed a distinctive cobweb-like meshwork which was parallel to the cartilage surface. In the superficial zone, elastin fibers were well organized in a preferred orientation which was parallel to collagen fibers. In the deep zone, no detectable elastin fiber was found. Moreover, differences in the organization of elastin fibers were also observed between articular cartilage from the tibial plateau, femoral condyle, and distal humerus. This study unravels the detailed microarchitecture of elastin fibers which display a well-organized three-dimensional versatile network in articular cartilage. Our findings imply that elastin fibers may play a crucial role in maintaining the integrity, elasticity, and the mechanical properties of articular cartilage, and that the local mechanical environment affects the architectural development of elastin fibers. PMID:23649803

  2. Bioactive glasses: Importance of structure and properties in bone regeneration

    NASA Astrophysics Data System (ADS)

    Hench, Larry L.; Roki, Niksa; Fenn, Michael B.

    2014-09-01

    This review provides a brief background on the applications, mechanisms and genetics involved with use of bioactive glass to stimulate regeneration of bone. The emphasis is on the role of structural changes of the bioactive glasses, in particular Bioglass, which result in controlled release of osteostimulative ions. The review also summarizes the use of Raman spectroscopy, referred to hereto forward as bio-Raman spectroscopy, to obtain rapid, real time in vitro analysis of human cells in contact with bioactive glasses, and the osteostimulative dissolution ions that lead to osteogenesis. The bio-Raman studies support the results obtained from in vivo studies of bioactive glasses, as well as extensive cell and molecular biology studies, and thus offers an innovative means for rapid screening of new bioactive materials while reducing the need for animal testing.

  3. Role versatility among men who have sex with men in urban Peru.

    PubMed

    Goodreau, Steven M; Peinado, Jesus; Goicochea, Pedro; Vergara, Jorge; Ojeda, Nora; Casapia, Martin; Ortiz, Abner; Zamalloa, Victoria; Galvan, Rosa; Sanchez, Jorge R

    2007-08-01

    Role versatility refers to the practice in which individual men who have sex with men (MSM) play both insertive and receptive sexual roles over time. Versatility has been thought to be relatively uncommon among Latin American MSM but possibly rising. Versatility has also been shown to be a potentially large population-level risk factor for HIV infection. In this study we examine the correlates of versatile behavior and identity among 2,655 MSM in six Peruvian cities. Versatile behavior with recent male partners was found in 9% of men and versatile ("moderno") identity was reported by 16%. Significant predictors included high education, white-collar occupation, sex work, and residence in Lima. Age was not significant in any analysis. Since sex work is negatively correlated with other predictors, versatile men appear to comprise two distinct sub-populations. Insertive-only men appear to play a strong role in bridging the HIV epidemic between MSM and women. PMID:17879166

  4. The TopClosure 3S System, for skin stretching and a secure wound closure.

    PubMed

    Topaz, Moris; Carmel, Narin-Nard; Silberman, Adi; Li, Ming Sen; Li, Yong Zhong

    2012-07-01

    The principle of stretching wound margins for primary wound closure is commonly practiced and used for various skin defects, leading at times to excessive tension and complications during wound closure. Different surgical techniques, skin stretching devices and tissue expanders have been utilized to address this issue. Previously designed skin stretching devices resulted in considerable morbidity. They were invasive by nature and associated with relatively high localized tissue pressure, frequently leading to necrosis, damage and tearing of skin at the wound margins. To assess the clinical effectiveness and performance and, to determine the safety of TopClosure for gradual, controlled, temporary, noninvasive and invasive applications for skin stretching and secure wound closing, the TopClosure device was applied to 20 patients for preoperative skin lesion removal and to secure closure of a variety of wound sizes. TopClosure was reinforced with adhesives, staples and/or surgical sutures, depending on the circumstances of the wound and the surgeon's judgment. TopClosure was used prior to, during and/or after surgery to reduce tension across wound edges. No significant complications or adverse events were associated with its use. TopClosure was effectively used for preoperative skin expansion in preparation for dermal resection (e.g., congenital nevi). It aided closure of large wounds involving significant loss of skin and soft tissue by mobilizing skin and subcutaneous tissue, thus avoiding the need for skin grafts or flaps. Following surgery, it was used to secure closure of wounds under tension, thus improving wound aesthetics. A sample case study will be presented. We designed TopClosure, an innovative device, to modify the currently practiced concept of wound closure by applying minimal stress to the skin, away from damaged wound edges, with flexible force vectors and versatile methods of attachment to the skin, in a noninvasive or invasive manner. PMID:22719176

  5. Spiritual and religious aspects of skin and skin disorders

    PubMed Central

    Shenefelt, Philip D; Shenefelt, Debrah A

    2014-01-01

    Skin and skin disorders have had spiritual aspects since ancient times. Skin, hair, and nails are visible to self and others, and touchable by self and others. The skin is a major sensory organ. Skin also expresses emotions detectable by others through pallor, coldness, “goose bumps”, redness, warmth, or sweating. Spiritual and religious significances of skin are revealed through how much of the skin has been and continues to be covered with what types of coverings, scalp and beard hair cutting, shaving and styling, skin, nail, and hair coloring and decorating, tattooing, and intentional scarring of skin. Persons with visible skin disorders have often been stigmatized or even treated as outcasts. Shamans and other spiritual and religious healers have brought about healing of skin disorders through spiritual means. Spiritual and religious interactions with various skin disorders such as psoriasis, leprosy, and vitiligo are discussed. Religious aspects of skin and skin diseases are evaluated for several major religions, with a special focus on Judaism, both conventional and kabbalistic. PMID:25120377

  6. Spiritual and religious aspects of skin and skin disorders.

    PubMed

    Shenefelt, Philip D; Shenefelt, Debrah A

    2014-01-01

    Skin and skin disorders have had spiritual aspects since ancient times. Skin, hair, and nails are visible to self and others, and touchable by self and others. The skin is a major sensory organ. Skin also expresses emotions detectable by others through pallor, coldness, "goose bumps", redness, warmth, or sweating. Spiritual and religious significances of skin are revealed through how much of the skin has been and continues to be covered with what types of coverings, scalp and beard hair cutting, shaving and styling, skin, nail, and hair coloring and decorating, tattooing, and intentional scarring of skin. Persons with visible skin disorders have often been stigmatized or even treated as outcasts. Shamans and other spiritual and religious healers have brought about healing of skin disorders through spiritual means. Spiritual and religious interactions with various skin disorders such as psoriasis, leprosy, and vitiligo are discussed. Religious aspects of skin and skin diseases are evaluated for several major religions, with a special focus on Judaism, both conventional and kabbalistic. PMID:25120377

  7. Surfactants and the skin.

    PubMed

    Dykes, P

    1998-02-01

    The skin surface is the interface between us, the organism, and the outside world. When we clean the skin we remove not only the bacteria, dirt and grease which have accumulated, but also part of our natural barrier - the stratum corneum. Corneocytes, both singly and in clumps, are released from the skin surface by the action of detergents and mechanical stimulation. So too are the lipids and proteins which make up the intercorneocyte region of the stratum corneum. The analysis of the types and amounts of materials released by a standard scrub procedure may prove useful in the selection of surfactants with particular properties. Changes in the physical properties of the skin occur after washing. For example, changes in skin surface pH and transepidermal water loss (a sensitive index of barrier function) are easily demonstrable. Excessive exposure to surfactants results in repeated damage to the stratum corneum which can in turn lead to an irritant dermatitis. Individual susceptibility to irritant dermatitis varies and this may be demonstrated using a simple patch test technique. This test is a way of potentially increasing the sensitivity of human based assays such as the soap chamber test by preselection of subjects. Alternatively it may be possible to use measurements of function such as transepidermal water loss or laser Doppler blood flow as an index of damage rather than conventional cutaneous irritancy. These approaches may help in the search for the ideal of a non-irritant cleanser. PMID:18505489

  8. Skin conditions: common skin rashes in infants.

    PubMed

    Zuniga, Ramiro; Nguyen, Tam

    2013-04-01

    Infants exhibit many skin rashes. Erythema toxicum neonatorum presents as erythematous macules, papules, and pustules on the face, trunk, and extremities; it typically resolves spontaneously within 1 week. Neonatal acne presents as comedones or erythematous papules on the face, scalp, chest, and back. Infantile acne is similar but starts after the neonatal period. Both conditions typically resolve spontaneously; failure to resolve within 1 year warrants evaluation for androgen excess. Neonatal cephalic pustulosis is an acne variant caused by hypersensitivity to Malassezia furfur. It is typically self-limited, but severe cases are managed with topical ketoconazole. Miliaria and milia are caused by sweat retention and present as tiny vesicles or papules; they resolve spontaneously. Contact diaper dermatitis is managed by keeping the diaper area clean and with open air exposure. Diaper dermatitis due to Candida albicans is managed with topical antifungals. Seborrheic dermatitis causes scaling on the scalp. Management involves shampooing and removing scales with a soft brush after applying mineral oil or petrolatum; severe cases are managed with tar or ketoconazole shampoo. Atopic dermatitis is related to food allergy in approximately one-third of children. Food allergy can be confirmed with oral food challenges or skin prick tests. Management includes elimination of irritants and triggers and use of low-potency topical steroids. PMID:23600337

  9. [Cytokines and skin diseases].

    PubMed

    Thestrup-Pedersen, K

    1995-01-01

    Many skin diseases such as eczema and psoriasis are characterised by a chronic inflammatory skin condition. In this respect they resemble other chronic diseases such as rheumatoid arthritis, bronchial asthma, ulcerous colitis and Crohn's disease. A persistent accumulation, predominantly of T-lymphocytes constitutes the central pathophysiological feature of such diseases. The past 15-20 years have witnessed the characterisation of an extensive series of peptides known as cytokines. These are soluble, relatively low molecular weight peptides which at low concentrations mediate regulation of cellular receptors, new phenotype expression, secretion and migration. Many cytokines have been found to be present in conjunction with skin diseases, and it is suggested that they are involved in the development of inflammation. PMID:7892122

  10. Sprayed skin turbine component

    DOEpatents

    Allen, David B

    2013-06-04

    Fabricating a turbine component (50) by casting a core structure (30), forming an array of pits (24) in an outer surface (32) of the core structure, depositing a transient liquid phase (TLP) material (40) on the outer surface of the core structure, the TLP containing a melting-point depressant, depositing a skin (42) on the outer surface of the core structure over the TLP material, and heating the assembly, thus forming both a diffusion bond and a mechanical interlock between the skin and the core structure. The heating diffuses the melting-point depressant away from the interface. Subsurface cooling channels (35) may be formed by forming grooves (34) in the outer surface of the core structure, filling the grooves with a fugitive filler (36), depositing and bonding the skin (42), then removing the fugitive material.

  11. Environment and the skin

    SciTech Connect

    Suskind, R.R. )

    1990-03-01

    The skin is an important organ of defense adaptation and a portal of entry for xenobiotics. It is vulnerable to physical, chemical, and biologic agents and capable of expressing responses to these agents in a variety of pathologic patterns. These patterns are characterized by morphologic and functional features which are elicited by careful examination and test procedures. Cutaneous cancer may result from exposure to nonionizing as well as ionizing radiation, to specific identifiable chemical hazards, and may be enhanced by trauma. Cutaneous hazards of chemical sources are largely found in the workplace and among consumer products, including drugs and toilet goods. Environmental skin diseases and injuries are preventable. Prior to use assessment for safety and for possible risks from exposure to an agent, product, or process is of primary importance in the prevention and control of environmental skin disease and injury.

  12. Skin friction balance

    NASA Technical Reports Server (NTRS)

    Ping, Tcheng (Inventor); Supplee, Frank H., Jr. (Inventor)

    1989-01-01

    A skin friction balance uses a parallel linkage mechanism to avoid inaccuracies in skin friction measurement attributable to off-center normal forces. The parallel linkage mechanism includes a stationary plate mounted in a cage, and an upper and lower movable plate which are linked to each other and to the stationary plate throught three vertical links. Flexure pivots are provided for pivotally connecting the links and the plates. A sensing element connected to the upper plate moves in response to skin friction, and the lower plate moves in the opposite direction of the upper plate. A force motor maintains a null position of the sensing element by exerting a restoring force in response to a signal generated by a linear variable differential transformer (LVDT).

  13. [Skin diseases with photosensitivity].

    PubMed

    Amblard, P; Leccia, M T

    1992-06-01

    Skin diseases associated with photosensitivity are numerous and may be divided into three main groups: photo-aggravated dermatoses, genophotodermatoses and metabolic photodermatoses. Photo-aggravated dermatoses are autonomous skin diseases in which exposure to sunlight may make the disease worse or precipitate its onset and/or its progressiveness; this group includes lupus erythematosus, autoimmune bullous diseases, acantolytic dyskeratoses, acne vulgaris, rosacea and cutaneous lymphoid infiltrates. To these must be added photosensitive forms of autonomous dermatoses such as atopic dermatitis, psoriasis, herpes labialis, erythema multiforme, granuloma and disseminated superficial actinic porokeratosis. Genophotodermatoses are genodermatoses which are made photosensitive by a recognized or as yet unidentified deficiency of the natural photoprotection system. In this group are albinism, vitiligo, xeroderma pigmentosum and poikiloderma. Metabolic photodermatoses are diseases in which photosensitization reactions, often revealing, are due to the accumulation in the skin of an endogenous chromophore as a result of a congenital (porphyria) or acquired (pellagra) enzymatic disorder. PMID:1529248

  14. Transparent active skin

    NASA Astrophysics Data System (ADS)

    Kwon, Hyeok-Yong; An, Kuang Jun; Kang, Junmo; Phuc, Vuong Hong; Toan, Nguyen Canh; Kim, Baek Chul; Chung, Jin Ah; Hong, Byung Hee; Choi, Jaeboong; Moon, Hyungpil; Koo, Jachoon; Nam, Jae-do; Choi, Hyouk Ryeol

    2011-04-01

    In this paper we present a transparent and stretchable dielectric elastomer actuator(DEA). The device, called "active skin" is under development as a new means of human interfaces. The active skin consists of elastomeric films sandwiched between compliant patterned electrodes. Thus, depending on the properties of the elastomer or electrodes, it is possible to realize a wide variety of implementations as transducers. As a critical issue of the transparent active skin, transparency in the electrode including that of the substrate is challenging, which has not been solved yet. In this paper, a compliant, transparent and highly conductive electrode layer on the elastomeric film by using graphene is presented. The fabrication method of graphene electrodes dedicated to the elastomeric materials is addressed and its compatibility to the existing materials is discussed. Also, preliminary implementations on the embossed actuator are given to validate the proposed idea.

  15. Micropatterning of bioactive glass nanoparticles on chitosan membranes for spatial controlled biomineralization.

    PubMed

    Luz, Gisela M; Boesel, Luciano; del Campo, Arnzazu; Mano, Joo F

    2012-05-01

    Bioactive glass nanoparticles (BG-NPs) capable of inducing apatite precipitation upon immersion in simulated body fluid (SBF) were patterned on free-standing chitosan membranes by microcontact printing using a poly(dimethylsiloxane) (PDMS) stamp inked in a BG-NPs pad. Formation of the patterns was characterized by scanning electron microscopy (SEM). Mineralization of the bioactive glass patterns was induced in vitro by soaking the samples in SBF over different time points up to 7 days. The confined apatite deposition in the patterned regions with diameters of 50 ?m was confirmed by Fourier-transformed infrared spectroscopy (FTIR), energy-dispersive X-ray (EDX) analysis, and SEM. In vitro tests confirmed the preferential attachment and proliferation of L929 cells to the areas printed with BG-NPs of the membranes. This approach permits one to spatially control the properties of biomaterials at the microlevel and could be potentially used in guided tissue regeneration for skin, vascular, articular, and bone tissue engineering and in cellular cocultures or to develop substrates able to confine cells in regions with controlled geometry at the cell's length scale. PMID:22480212

  16. Characterization and bioactivity of nano-submicro octacalcium phosphate/gelatin composite

    NASA Astrophysics Data System (ADS)

    Miura, Kei-ichiro; Anada, Takahisa; Honda, Yoshitomo; Shiwaku, Yukari; Kawai, Tadashi; Echigo, Seishi; Takahashi, Tetsu; Suzuki, Osamu

    2013-10-01

    The present study was designed to investigate the physicochemical and bioactive properties of a nano-submicro sized octacalcium phosphate (OCP)-dispersed gelatin (Gel) composite (nano-submicro OCP/Gel) used as a bone substitute material in various bone defects. Well-grown, synthesized OCP was mechanically ground from 100 to 300 ?m-sieved granules to particles that were approximately 500 nm in size. Then, 50 wt% of the nano-submicro OCP was mixed with porcine skin-derived acid extracted gelatin. The mixture was molded and lyophilized and then subjected to dehydrothermal crosslinking. X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy showed that the structure of OCP was retained even after mechanical grinding to a nano-submicro scale level as well as inclusion in the Gel matrix. The bioactivity of nano-submicro OCP/Gel was examined by immersing the composite in simulated body fluid (SBF) for 7 days and by implanting it in rat critical-sized calvaria defects for 8 weeks. The nano-submicro OCP tended to convert to low crystalline hydroxyapatite (HA) in SBF as assessed by XRD. The nano-submicro OCP/Gel exhibited osteoconductivity in vivo, yielding new bone formation that was closely associated with the implanted composite. These results suggest that the nano-submicro OCP/Gel composite exhibits similar osteoconductivity as observed in other OCP-based materials previously reported and could be used as a bone substitute material for repairing various defects in bone.

  17. Polygonum cuspidatum extracts as bioactive antioxidaion, anti-tyrosinase, immune stimulation and anticancer agents.

    PubMed

    Lee, Chih-Chen; Chen, Yen-Ting; Chiu, Chien-Chih; Liao, Wei-Ting; Liu, Yung-Chuan; David Wang, Hui-Min

    2015-04-01

    In our study, it was applied for the technology of supercritical fluid carbon dioxide extraction to achieve biological constitutes from a Taiwan native plant, Polygonum cuspidatum. We developed bioactive effects of P.cuspidatum extracts via multiple examinations that established bio-purposes at a range of dosage ranges. The research of P.cuspidatum extracts indicated that they possessed anti-oxidative properties on radical-scavenging abilities, reducing activities and metal chelating powers in dose-dependant manners. The extracts also had minor in vitro mushroom tyrosinase suppression and decreased cellular tyrosinase activities and melanin production in B16-F10 cells. Immunologically, P.cuspidatum extracts enhanced the release of tumor necrosis factor ? (TNF-?) induced by THP-1 macrophage cell line. In addition, the cell proliferation showed anti-proliferation in dose-dependent manner on human skin melanoma cells, A375 and A375.S2, of the extracts suggesting biological constitutes employed the anti-cancer possessions. This is the first statement presenting bioactivities on P.cuspidatum extracts including anti-oxidation, immune stimulation, anti-tyrosinase and anti-melanoma as far as we know. PMID:25311751

  18. [Radiotherapy and skin tumors].

    PubMed

    Calitchi, E; Kirova, Y; Le Bourgeois, J P

    1998-01-01

    Radiotherapy plays an important role in the treatment of skin tumours. For skin carcinomas, external irradiation (kilovoltage X-rays or electrons according to clinical characteristics) is more valuable than interstitial brachytherapy, which is recommended for tumours of the lip and of the nasal vestibule. In mycosis fungoides, total cutaneous electron beam radiation therapy is efficient for patients with limited superficial plaques. In the classical form of Kaposi's sarcoma, radiotherapy can achieve local control whereas it obtains good palliative results in the epidemic form. PMID:9868400

  19. Study of surfactant-skin interactions by skin impedance measurements.

    PubMed

    Lu, Guojin; Moore, David J

    2012-02-01

    The stratum corneum (SC) plays a very critical physiological role as skin barrier in regulating water loss through the skin and protects the body from a wide range of physical and chemical exogenous insults. Surfactant-containing formulations can induce skin damage and irritation owing to surfactant absorption and penetration. It is generally accepted that reduction in skin barrier properties occurs only after surfactants have penetrated/permeated into the skin barrier. To mitigate the harshness of surfactant-based cleansing products, penetration/permeation of surfactants should be reduced. Skin impedance measurements have been taken in vitro on porcine skin using vertical Franz diffusion cells to investigate the impact of surfactants, temperature and pH on skin barrier integrity. These skin impedance results demonstrate excellent correlation with other published methods for assessing skin damage and irritation from different surfactant chemistry, concentration, pH, time of exposure and temperature. This study demonstrates that skin impedance can be utilized as a routine approach to screen surfactant-containing formulations for their propensity to compromise the skin barrier and hence likely lead to skin irritation. PMID:21923733

  20. [Structure basis of versatile base recognition of MBD4].

    PubMed

    Ariyoshi, Mariko; Otani, Junji; Shirakawa, Masahiro

    2015-01-01

    DNA methylation is one of the major epigenetic marks in the mammalian genome to define chromatin higher-order structure, and plays essential roles in various developmental processes. In the mammalian genome, DNA methylation mainly occurs at the 5th position of cytosine bases in a palindromic 5'-CG-3'dinucleotide sequence. Methyl CpG binding domain (MBD) proteins recognize symmetrically methylated CpG sites (5mCG/5mCG) through a conserved MBD, and recruit transcriptional repressors or chromatin modifiers. One of the MBD proteins, MBD4, uniquely contains a C-terminal glycosylation domain together with an N-terminal MBD, and functions as a mismatch DNA repair enzyme specific for T/G or U/G mismatch bases generated by spontaneous deamination of 5-methylcytosine. The base excision activity of MBD4 is also implicated in active DNA demethylation initiated by the conversion of 5-methylcytosine to thymine by deaminases. Unlike other MBD proteins, MBD4 recognizes not only 5mCG/5mCG but also T/G mismatched sites generated by spontaneous deamination of 5-methylcytosine (5mCG/TG). In addition, our biochemical data demonstrate that MBD also binds to intermediates in DNA demethylation pathways, such as 5-hydroxymethyl-cytosine (hmC), 5-carboxyl-cytosine and 5-hydroxy-uracil. The crystal structures of MBDMBD4 in complex with 5mCG/TG, 5mCG/5mCG or 5mCG/hmCG provide new structural insights into the versatility of base recognition by MBD4. A DNA interface of MBD4 has flexible structural features, in which an extensive hydration water network supports the versatile base specificity of MBD4. The versatile base recognition by MBDMBD4 implies multi-functional roles of MBD4 in the regulation of dynamic DNA methylation patterns. PMID:25743892

  1. Nitrogen-Based Diazeniumdiolates: Versatile Nitric Oxide-Releasing Compounds for Biomedical Research and Potential Clinical Applications

    NASA Astrophysics Data System (ADS)

    Saavedra, Joseph E.; Keefer, Larry K.

    2002-12-01

    Nitric oxide-generating ions of the nitrogen-diazeniumdiolate class with the general structure R1R2N-[N(O)NO]1 have been prepared by exposing primary, secondary, and polyamines to nitric oxide (NO). The resulting complexes regenerate bioactive NO at physiological pH with half-lives ranging from 2 seconds to 20 hours. An important goal in our research is to deliver NO to a specific organ or cell type where it is needed without affecting other NO-sensitive parts of the anatomy. By taking advantage of the remarkable chemical versatility of diazeniumdiolates, we have developed general strategies to prepare either tissue-selective NO donor drugs or materials containing NO delivery agents that can be physically placed near the target sites. Inhibition of blood coagulation, induction of penile erection, relief of pulmonary hypertension, and reversal of cerebral vasospasm are a few examples of their potential clinical applications.

    See Featured Molecules.

  2. A Single Versatile Appliance for Habit Interception and Crossbite Correction

    PubMed Central

    Zameer, Mohammed; Basheer, Syed Nahid; Reddy, Arun; Kovvuru, Suresh Kumar

    2015-01-01

    Digit sucking is a common childhood behavior, which has an adaptive value for children up to the fourth year of life. It is usually associated with oral pleasure and self-comforting behavior. But chronic practice may produce deleterious effect in the form of dental and skeletal deformities. Adjunctive therapy using bluegrass appliance as a permanent reminder and quadhelix appliance as a reminder as well as a slow palatal expander has proven successful in intercepting digit-sucking habit and expanding the arch for crossbite correction. In the present case, a versatile modified quadhelix appliance incorporating a roller was designed to clinically correct the habit and its resulting dentofacial deformities. PMID:26640722

  3. A versatile stepping motor controller for systems with many motors

    SciTech Connect

    Feng, S.K.; Siddons, D.P.

    1989-01-01

    A versatile system for controlling beamlines or complex experimental setups is described. The system as currently configured can control up to 32 motors, with all motors capable of full speed operation concurrently. There are 2 limit switch inputs for each motor, and a further input to accept a reference position marker. The motors can be controlled via a front panel keyboard with display, or by a host computer over an IEEE-488 interface. Both methods can be used together if required. There is an emergency stop'' key on the front panel keyboard to stop the motion of all motors without losing track of the motors' position. 3 refs., 4 figs., 1 tab.

  4. The acoustic vector sensor: a versatile battlefield acoustics sensor

    NASA Astrophysics Data System (ADS)

    de Bree, Hans-Elias; Wind, Jelmer W.

    2011-06-01

    The invention of the Microflown sensor has made it possible to measure acoustic particle velocity directly. An acoustic vector sensor (AVS) measures the particle velocity in three directions (the source direction) and the pressure. The sensor is a uniquely versatile battlefield sensor because its size is a few millimeters and it is sensitive to sound from 10Hz to 10kHz. This article shows field tests results of acoustic vector sensors, measuring rifles, heavy artillery, fixed wing aircraft and helicopters. Experimental data shows that the sensor is suitable as a ground sensor, mounted on a vehicle and on a UAV.

  5. ICAN: A versatile code for predicting composite properties

    NASA Technical Reports Server (NTRS)

    Ginty, C. A.; Chamis, C. C.

    1986-01-01

    The Integrated Composites ANalyzer (ICAN), a stand-alone computer code, incorporates micromechanics equations and laminate theory to analyze/design multilayered fiber composite structures. Procedures for both the implementation of new data in ICAN and the selection of appropriate measured data are summarized for: (1) composite systems subject to severe thermal environments; (2) woven fabric/cloth composites; and (3) the selection of new composite systems including those made from high strain-to-fracture fibers. The comparisons demonstrate the versatility of ICAN as a reliable method for determining composite properties suitable for preliminary design.

  6. A versatile FACTS device model for powerflow and stability simulations

    SciTech Connect

    Arabi, S.; Kundur, P.

    1996-11-01

    While early FACTs devices consisted mainly of thyristor-controlled/switched RLC/transformer components, the newer generation is based on the self-commutated voltage-sourced converter. The variety of devices and applications, and the changing nature of the technology, call for versatile modelling capabilities at different levels of detail. This paper describes a model conceived as a coordinated and interconnected set of controllable shunt and series elements. For each device, functional characteristics, typical settings and controls, and simulation examples are presented. The model is capable of representing virtually any FACTS device for powerflow and all types of stability simulations.

  7. Fabrication of versatile nanocomponents using single-crystalline Au nanoplates

    NASA Astrophysics Data System (ADS)

    Yun, Yong Ju; Park, Gwangseo; Ah, Chil Seong; Park, Hyung Ju; Yun, Wan Soo; Ha, Dong Han

    2005-12-01

    We suggest an approach to the fabrication of versatile nanocomponents designed deliberately by selective Ga+ focused-ion-beam etching or Ar+ ion milling of single-crystalline Au nanoplates synthesized by the chemical reaction. The nanocomponents have various shapes like gear, wheel, dumbbell, square and letter "A" with in-plane size of about 400nm and thickness of 40-50nm. They can be picked up or moved freely one by one to be assembled into sophisticated nanodevices or micromachines. The applicability of our approach both to the fundamental research and to the applied research is discussed.

  8. Fabrication of versatile nanocomponents using single-crystalline Au nanoplates

    SciTech Connect

    Yun, Yong Ju; Park, Gwangseo; Ah, Chil Seong; Park, Hyung Ju; Yun, Wan Soo; Ha, Dong Han

    2005-12-05

    We suggest an approach to the fabrication of versatile nanocomponents designed deliberately by selective Ga{sup +} focused-ion-beam etching or Ar{sup +} ion milling of single-crystalline Au nanoplates synthesized by the chemical reaction. The nanocomponents have various shapes like gear, wheel, dumbbell, square and letter 'A' with in-plane size of about 400 nm and thickness of 40-50 nm. They can be picked up or moved freely one by one to be assembled into sophisticated nanodevices or micromachines. The applicability of our approach both to the fundamental research and to the applied research is discussed.

  9. The versatility of furfuryl alcohols and furanoxonium ions in synthesis.

    PubMed

    Palframan, Matthew J; Pattenden, Gerald

    2014-07-14

    Substituted furfuryl alcohols are extraordinarily versatile starting materials in synthesis. They are precursors to furanoxonium ion intermediates which are implicated in the Piancatelli reaction (leading to 2-cyclopentenones) and in the synthesis of novel dihydrofuran-based exo enol ether/cyclic ketal natural products. They are also intermediates in a recently discovered (4+3) cycloaddition reaction with 1,3-dienes leading to furan ring-fused cycloheptenes. Here we provide a perspective on recent developments in these areas of synthesis, alongside recent applications of the Achmatowicz reaction and [5+2] cycloaddition reactions of the resulting oxidopyrylium ions. PMID:24728307

  10. Ferrimagnetic nanocrystal assemblies as versatile magnetic particle hyperthermia mediators.

    PubMed

    Sakellari, D; Brintakis, K; Kostopoulou, A; Myrovali, E; Simeonidis, K; Lappas, A; Angelakeris, M

    2016-01-01

    Colloidal nanocrystal assemblies (nanoclusters), consisting of 13 nm iron oxide nanocrystals, were synthesized in various sizes (45-98 nm), and were investigated as heating mediators for magnetic particle hyperthermia. The colloidal nanocrystal clusters show enhanced heating efficiency in comparison with their constituent primary iron oxide nanocrystals due to collective magnetic features. The fine tuning of intra-cluster magnetic interactions results to the domination of the hysteresis losses mechanism over the relaxation loss heating contributions and eventually to a versatile magnetic particle hyperthermia mediator. PMID:26478302

  11. Versatile reactions of organoboron polymers prepared by hydroboration polymerization

    SciTech Connect

    Chujo, Y.; Tomita, I.; Morimoto, M.; Takizawa, N.; Sakurai, T.

    1993-12-31

    Hydroboration polymerization of dienes and thexylborane produces organoboron polymers, which can be regarded as a polymer homologue of trialkylboranes. In other words, the obtained polymers can be expected as a novel type of reactive polymers. The present paper describes versatile reactions of organoboron polymers prepared by hydroboration polymerization. For example, the reactions with carbon monoxide or with KCN were followed by the oxidative treatment to produce the corresponding poly(alcohol)s or poly(ketone)s, respectively. The organoboron polymers were also reacted with bromopyridyl anion or with furyl anion to form cyano- or hydroxyl containing polymers via ring-opening of pyridine or furan, respectively.

  12. A versatile detector for total fluorescence and electron yield experiments

    SciTech Connect

    Thielemann, N.; Hoffmann, P.; Foehlisch, A.

    2012-09-15

    The combination of a non-coated silicon photodiode with electron repelling meshes makes a versatile detector for total fluorescence yield and electron yield techniques highly suitable for x-ray absorption spectroscopy. In particular, a copper mesh with a bias voltage allows to suppress or transmit the electron yield signal. The performance of this detection scheme has been characterized by near edge x-ray absorption fine structure studies of thermal oxidized silicon and sapphire. The results show that the new detector probes both electron yield and for a bias voltage exceeding the maximum photon energy the total fluorescence yield.

  13. Parallel optics technology assessment for the versatile link project

    SciTech Connect

    Chramowicz, J.; Kwan, S.; Rivera, R.; Prosser, A.; /Fermilab

    2011-01-01

    This poster describes the assessment of commercially available and prototype parallel optics modules for possible use as back end components for the Versatile Link common project. The assessment covers SNAP12 transmitter and receiver modules as well as optical engine technologies in dense packaging options. Tests were performed using vendor evaluation boards (SNAP12) as well as custom evaluation boards (optical engines). The measurements obtained were used to compare the performance of these components with single channel SFP+ components operating at a transmission wavelength of 850 nm over multimode fibers.

  14. A Versatile Approach Towards Nucleobase-Modified Aptamers.

    PubMed

    Tolle, Fabian; Brndle, Gerhard M; Matzner, Daniel; Mayer, Gnter

    2015-09-01

    A novel and versatile method has been developed for modular expansion of the chemical space of nucleic acid libraries, thus enabling the generation of nucleobase-modified aptamers with unprecedented recognition properties. Reintroduction of the modification after enzymatic replication gives broad access to many chemical modifications. This wide applicability, which is not limited to a single modification, will rapidly advance the application of in?vitro selection approaches beyond what is currently feasible and enable the generation of aptamers to many targets that have so far not been addressable. PMID:26224087

  15. Versatile cold atom source for multi-species experiments

    SciTech Connect

    Paris-Mandoki, A.; Jones, M. D.; Nute, J.; Warriar, S.; Hackermller, L.; Wu, J.

    2014-11-15

    We present a dual-species oven and Zeeman slower setup capable of producing slow, high-flux atomic beams for loading magneto-optical traps. Our compact and versatile system is based on electronic switching between different magnetic field profiles and is applicable to a wide range of multi-species experiments. We give details of the vacuum setup, coils, and simple electronic circuitry. In addition, we demonstrate the performance of our system by optimized, sequential loading of magneto-optical traps of lithium-6 and cesium-133.

  16. Engineering organic macrocycles and cages: versatile bonding approaches.

    PubMed

    Huang, Sheng-Li; Jin, Guo-Xin; Luo, He-Kuan; Hor, T S Andy

    2015-01-01

    The emergence of supramolecular chemistry has led to the discovery of a rising number of macrocycles and cages with a range of functionalities. Most of these supramolecular aggregates are metal coordination networks, whereas pure organic assemblies are less developed. Organic macrocycles and cages have the advantages of chemical robustness, processability in organic solvents, and suitability for pilot-scale applications. They are constructed primarily from covalent bonds, with irreversible and reversible bond types. We herein highlight the use of different versatile bonding approaches in engineering these soft materials, as well as their emerging applications, such as gas storage, thin films, liquid crystals, and catalysis. PMID:25403872

  17. Algae biofuels: versatility for the future of bioenergy.

    PubMed

    Jones, Carla S; Mayfield, Stephen P

    2012-06-01

    The world continues to increase its energy use, brought about by an expanding population and a desire for a greater standard of living. This energy use coupled with the realization of the impact of carbon dioxide on the climate, has led us to reanalyze the potential of plant-based biofuels. Of the potential sources of biofuels the most efficient producers of biomass are the photosynthetic microalgae and cyanobacteria. These versatile organisms can be used for the production of bioethanol, biodiesel, biohydrogen, and biogas. In fact, one of the most economic methods for algal biofuels production may be the combined biorefinery approach where multiple biofuels are produced from one biomass source. PMID:22104720

  18. A versatile feedback controller for electro-mechanical stimulation devices.

    PubMed

    Bohnenberger, J; Seyfarth, E A; Barth, F G

    1983-12-01

    Neurophysiological and behavioral work often requires that various laboratory stimulators be feedback-stabilized. We describe the design and performance of a versatile electronic controller that can be used to extend and flatten the frequency response of commercially available stimulating devices. The design includes flexible proportional-integral-derivative control action and active second-order, high-pass compensation. As an example application of this controller to 3 different electro-mechanical vibrator/transducer combinations demonstrates that the useful frequency response can be extended by more than a decade as compared with the uncontrolled device. PMID:6668958

  19. Surface plasmon resonance-enabled antibacterial digital versatile discs

    NASA Astrophysics Data System (ADS)

    Dou, Xuan; Chung, Pei-Yu; Jiang, Peng; Dai, Jianli

    2012-02-01

    We report the achievement of effective sterilization of exemplary bacteria including Escherichia coli and Geobacillus stearothermophilus spores on a digital versatile disc (DVD). The spiral arrangement of aluminum-covered pits generates strong surface plasmon resonance (SPR) absorption of near-infrared light, leading to high surface temperature that could even damage the DVD plastics. Localized protein denaturation and high sterilization efficiency have been demonstrated by using a fluorescence microscope and cell cultures. Numerical simulations have also been conducted to model the SPR properties and the surface temperature distribution of DVDs under laser illumination. The theoretical predictions agree reasonably well with the experimental results.

  20. Caffeic acid phenethyl ester exhibiting distinctive binding interaction with human serum albumin implies the pharmacokinetic basis of propolis bioactive components.

    PubMed

    Li, Hongliang; Wu, Fan; Tan, Jing; Wang, Kai; Zhang, Cuiping; Zheng, Huoqing; Hu, Fuliang

    2016-04-15

    Caffeic acid phenethyl ester (CAPE), as one of the major bioactive components present in propolis, exhibits versatile bioactivities, especially for its potent cytotoxic effects on several cancer cell models. To understand the pharmacokinetic characteristics of CAPE, the binding interaction between CAPE and human serum albumin (HSA) was investigated in vitro using multiple spectroscopic methods and molecular docking. The results reveal that CAPE exhibits a distinctive binding interaction with HSA comparing with other propolis components. The association constant KA (Lmol(-1)) of the binding reaches 10(6) order of magnitude, which is significantly stronger than the other components of propolis. Based on the theory of fluorescence resonance energy transfer, the binding distance was calculated as 5.7nm, which is longer than that of the other components of propolis. The thermodynamic results indicate that the binding is mainly driven by hydrogen bonds and van der Waals force. The docking and drugs (warfarin and ibuprofen) competitive results show that CAPE is located in the subdomain IIA (Sudlow's site I, FA7) of HSA, and Gln196 and Lys199 contribute to the hydrogen bonds. Circular dichroism spectra suggest an alteration of the secondary structure of HSA due to its partial unfolding in the presence of CAPE. PMID:26829518

  1. Bioactive properties of honey with propolis.

    PubMed

    Osés, S M; Pascual-Maté, A; Fernández-Muiño, M A; López-Díaz, T M; Sancho, M T

    2016-04-01

    Nowadays, propolis is used as an innovative preservative and as a bioactive food supplement. Due to its bitter and astringent flavour, propolis is hardly accepted by consumers. The aim of this study was to obtain a likeable food product made with honey and propolis, whose antimicrobial, antioxidant and anti-inflammatory properties were enhanced in comparison with those of the base honeys used. 0.1%, 0.3% and 0.5% soft propolis extracts were added to honeys and the products that most appealed to the users were subjected to further research. Total phenolics, flavonoids, ABTS free radical and hydroxyl radicals scavenging and anti-inflammatory activities increased in all mixtures. Antimicrobial activity of the combined products showed synergic effects, resulting in higher results than those of the base honeys and propolis extracts. Therefore, honeys enriched with small amounts of propolis extracts are promising functional foods. PMID:26593609

  2. A compilation of Bioactive Compounds from Ayurveda

    PubMed Central

    Samy, Ramar Perumal; Pushparaj, Peter Natesan; Gopalakrishnakone, Ponnampalam

    2008-01-01

    This review deals with the key bioactive compounds and the role of medicinal plants in Ayurvedic systems of medicine in India and their earlier investigation. There has been an increase in demand for the Phytopharmaceutical products of Ayurv?da in Western countries, because of the fact that the allopathic drugs have more side effects. Many pharmaceutical companies are now concentrating on manufacturing of Ayurv?dic Phytopharmaceutical products. Ayurv?da is the Indian traditional system of medicine, which also deals about pharmaceutical science. Different type of plant parts used for the Ayurvedic formulation; overall out line of those herbal scenario and its future prospects for the scientific evaluation of medicinal plants used by traditional healers are also discussed. In India most of them, where Ayurvedic treatment is frequently used, for their ailments and provides instructions to local people how to prepare medicine from the herbs. As much as possible importance is also given for the taxonomic literature. PMID:19238245

  3. Bioactive Compounds Found in Brazilian Cerrado Fruits.

    PubMed

    Bailão, Elisa Flávia Luiz Cardoso; Devilla, Ivano Alessandro; da Conceição, Edemilson Cardoso; Borges, Leonardo Luiz

    2015-01-01

    Functional foods include any natural product that presents health-promoting effects, thereby reducing the risk of chronic diseases. Cerrado fruits are considered a source of bioactive substances, mainly phenolic compounds, making them important functional foods. Despite this, the losses of natural vegetation in the Cerrado are progressive. Hence, the knowledge propagation about the importance of the species found in Cerrado could contribute to the preservation of this biome. This review provides information about Cerrado fruits and highlights the structures and pharmacologic potential of functional compounds found in these fruits. Compounds detected in Caryocar brasiliense Camb. (pequi), Dipteryx alata Vog. (baru), Eugenia dysenterica DC. (cagaita), Eugenia uniflora L. (pitanga), Genipa americana L. (jenipapo), Hancornia speciosa Gomes (mangaba), Mauritia flexuosa L.f. (buriti), Myrciaria cauliflora (DC) Berg (jabuticaba), Psidium guajava L. (goiaba), Psidium spp. (araçá), Solanum lycocarpum St. Hill (lobeira), Spondias mombin L. (cajá), Annona crassiflora Mart. (araticum), among others are reported here. PMID:26473827

  4. Electrospinning bioactive supramolecular polymers from water.

    PubMed

    Tayi, Alok S; Pashuck, E Thomas; Newcomb, Christina J; McClendon, Mark T; Stupp, Samuel I

    2014-04-14

    Electrospinning is a high-throughput, low-cost technique for manufacturing long fibers from solution. Conventionally, this technique is used with covalent polymers with large molecular weights. We report here the electrospinning of functional peptide-based supramolecular polymers from water at very low concentrations (<4 wt %). Molecules with low molecular weights (<1 kDa) could be electrospun because they self-assembled into one-dimensional supramolecular polymers upon solvation and the critical parameters of viscosity, solution conductivity, and surface tension were optimized for this technique. The supramolecular structure of the electrospun fibers could ensure that certain residues, like bioepitopes, are displayed on the surface even after processing. This system provides an opportunity to electrospin bioactive supramolecular materials from water for biomedical applications. PMID:24697625

  5. Biomimetic and nanostructured hybrid bioactive glass.

    PubMed

    Zhou, Xianfeng; Sahai, Nita; Qi, Lin; Mankoci, Steven; Zhao, Weilong

    2015-05-01

    Inspired by nature's toughening mechanisms, we designed a new polyhedral oligomeric silsesquioxane (POSS)-derived hybrid glass (PHG) that has covalent interactions on the molecular scale between the inorganic POSS cage and organic phase. These features allow "elastic deformation" of the inorganic POSS cage in limited scale. The final product is a bulk hybrid material with toughness (3.560.25MPam(1/2)) similar to natural bone (2.4-5.3MPam(1/2)). PHG exhibited excellent bioactivity by promoting the formation of plate-like hydroxyapatite on its surface in simulated body fluid and showed good cell adhesion. PHG also can be a platform to guide adipose tissue-derived mesenchymal stem cells differentiation and mineralization. The key structural features of this material can be used to guide the design of bio-inspired composites with unique toughness, which would be of great benefit to hard tissue engineering. PMID:25736490

  6. Bioactive Compounds Found in Brazilian Cerrado Fruits

    PubMed Central

    Bailão, Elisa Flávia Luiz Cardoso; Devilla, Ivano Alessandro; da Conceição, Edemilson Cardoso; Borges, Leonardo Luiz

    2015-01-01

    Functional foods include any natural product that presents health-promoting effects, thereby reducing the risk of chronic diseases. Cerrado fruits are considered a source of bioactive substances, mainly phenolic compounds, making them important functional foods. Despite this, the losses of natural vegetation in the Cerrado are progressive. Hence, the knowledge propagation about the importance of the species found in Cerrado could contribute to the preservation of this biome. This review provides information about Cerrado fruits and highlights the structures and pharmacologic potential of functional compounds found in these fruits. Compounds detected in Caryocar brasiliense Camb. (pequi), Dipteryx alata Vog. (baru), Eugenia dysenterica DC. (cagaita), Eugenia uniflora L. (pitanga), Genipa americana L. (jenipapo), Hancornia speciosa Gomes (mangaba), Mauritia flexuosa L.f. (buriti), Myrciaria cauliflora (DC) Berg (jabuticaba), Psidium guajava L. (goiaba), Psidium spp. (araçá), Solanum lycocarpum St. Hill (lobeira), Spondias mombin L. (cajá), Annona crassiflora Mart. (araticum), among others are reported here. PMID:26473827

  7. Electrospinning Bioactive Supramolecular Polymers from Water

    PubMed Central

    2015-01-01

    Electrospinning is a high-throughput, low-cost technique for manufacturing long fibers from solution. Conventionally, this technique is used with covalent polymers with large molecular weights. We report here the electrospinning of functional peptide-based supramolecular polymers from water at very low concentrations (<4 wt %). Molecules with low molecular weights (<1 kDa) could be electrospun because they self-assembled into one-dimensional supramolecular polymers upon solvation and the critical parameters of viscosity, solution conductivity, and surface tension were optimized for this technique. The supramolecular structure of the electrospun fibers could ensure that certain residues, like bioepitopes, are displayed on the surface even after processing. This system provides an opportunity to electrospin bioactive supramolecular materials from water for biomedical applications. PMID:24697625

  8. [Natural bioactive agents in liver therapy].

    PubMed

    Blzovics, Anna

    2015-11-22

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

  9. Bioactive glass coatings for orthopedic metallic implants

    SciTech Connect

    Lopez-Esteban, Sonia; Saiz, Eduardo; Fujino, Sigheru; Oku, Takeo; Suganuma, Katsuaki; Tomsia, Antoni P.

    2003-06-30

    The objective of this work is to develop bioactive glass coatings for metallic orthopedic implants. A new family of glasses in the SiO2-Na2O-K2O-CaO-MgO-P2O5 system has been synthesized and characterized. The glass properties (thermal expansion, softening and transformation temperatures, density and hardness) are in line with the predictions of established empirical models. The optimized firing conditions to fabricate coatings on Ti-based and Co-Cr alloys have been determined and related to the glass properties and the interfacial reactions. Excellent adhesion to alloys has been achieved through the formation of 100-200 nm thick interfacial layers (Ti5Si3 on Ti-based alloys and CrOx on Co-Cr). Finally, glass coatings, approximately 100 mu m thick, have been fabricated onto commercial Ti alloy-based dental implants.

  10. Secondary metabolites and bioactivities of Albizia anthelmintica

    PubMed Central

    Mohamed, Tahia K.; Nassar, Mahmoud I.; Gaara, Ahmed H.; El-Kashak, Walaa A.; Brouard, Iaki; El-Toumy, Sayed A.

    2013-01-01

    Background: Albizia species are rich in phenolics and terpenes in the different plant organs. They are widely used in traditional Chinese medicine. So this study investigated the phytochemical and biological activities of Albizia Anthelmintica. Materials and Methods: Column chromatography has been performed for the isolation of compounds. Bioactivity studies of A. anthelmintica leaves were carried out on aqueous ethanol extract and some pure compounds were tested for their antioxidant activities. Results: Eight compounds have been isolated for the first time from A. anthelmintica. The aqueous ethanol extract of A. anthelmintica showed moderate anti-inflammatory activity and significant for both analgesic and antioxidant activities. Quercetin-3-O-?-D-glucopyranoside, kaempferol-3-O-?-D-glucopyranoside, kaempferol-3-O-(6?-O-galloyl-?-D-glucopyranoside and quercetin-3-O-(6?-O-galloyl-?-D-glucopyranoside) exhibited potent antioxidant scavenging activity towards diphenyl-picrylhydrazine. PMID:23798881

  11. About Skin-to-Skin Care (Kangaroo Care)

    MedlinePLUS

    ... Size Email Print Share About Skin-to-Skin Care Page Content Article Body You may be able ... care, also called kangaroo care. What is Kangaroo Care? Kangaroo care was developed in South America as ...

  12. Influence of mental stress on platelet bioactivity

    PubMed Central

    Koudouovoh-Tripp, Pia; Sperner-Unterweger, Barbara

    2012-01-01

    It is well established that various mental stress conditions contribute, or at least influence, underlying pathophysiological mechanisms in somatic, as well as in psychiatric disorders; blood platelets are supposed to represent a possible link in this respect. The anculeated platelets are the smallest corpuscular elements circulating in the human blood. They display different serotonergic markers which seem to reflect the central nervous serotonin metabolism. They are known as main effectors in haematological processes but recent research highlights their role in the innate and adaptive immune system. Platelets are containing a multitude of pro-inflammatory and immune-modulatory bioactive compounds in their granules and are expressing immune-competent surface markers. Research gives hint that platelets activation and reactivity is increased by mental stress. This leads to enhanced cross talk with the immune system via paracrine secretion, receptor interaction and formation of platelet leucocyte-aggregates. Recently it has been demonstrated that the immune system can have a remarkable impact in the development of psychiatric disorders. Therefore platelets represent an interesting research area in psychiatry and their role as a possible biomarker has been investigated. We review the influence of mental stress on what is termed platelet bioactivity in this article, which subsumes the mainly immune-modulatory activity of platelets in healthy volunteers, elderly persons with chronic care-giving strain, patients with cardiovascular diseases who are prone to psychosocial stress, as well as in patients with posttraumatic stress disorder. Research data suggest that stress enhances platelet activity, reactivity and immune-modulatory capacities. PMID:24175179

  13. Rowanberry phenolics: compositional analysis and bioactivities.

    PubMed

    Kylli, Petri; Nohynek, Liisa; Puupponen-Pimi, Riitta; Westerlund-Wikstrm, Benita; McDougall, Gordon; Stewart, Derek; Heinonen, Marina

    2010-11-24

    Berries contain a large variety of different phenolic compounds such as anthocyanins, flavonols, tannins, and phenolic acids. Due to variation in the nature and content of the phenolic compounds, the antioxidant effect and other bioactivities of berry phenolics are strongly dependent on the berry raw material as the activities differ between the different phenolic constituents. In the present study, wild rowanberries ( Sorbus aucuparia ) and four cultivated sweet rowanberries, Burka, Granatnaja, Titan, and Zoltaja, were characterized for their phenolic composition and screened for antioxidant, antimicrobial, and antiadhesive activities. The HPLC and LC-MS analyses of phenolic composition revealed that the main phenolic constituents were caffeoylquinic acids, varying from 56 to 80% total phenolics. The cultivated species contained less caffeoylquinic acids and more anthocyanins (up to 28.5%). The phenolics derived from wild rowanberries were significantly effective at inhibiting lipid oxidation both in liposomes and in emulsions, especially when assessed by inhibition of the formation of hexanal (86-97% inhibition depending on concentration). The increase in anthocyanin content in the cultivated species did not result in significantly increased antioxidant activity. Both wild and cultivated rowanberry phenolics exhibited a bacteriostatic effect toward Staphylococcus aureus . In addition, the phenolic extract from Zoltaja was weakly inhibitory toward Salmonella sv. Typhimurium, whereas both Zoltaja- and Granatnaja-derived phenolics retarded Escherichia coli growth. The phenolic extracts of wild rowanberries and Burka showed an inhibitory effect on hemagglutination of E. coli HB101 (pRR7), which expresses the M hemagglutinin. It can be concluded that cultivation of rowanberries resulted in increased anthocyanin content, but this did not diminish their bioactivity in comparison to wild rowanberries rich in caffeoylquinic acids. PMID:21038891

  14. A review of the bioactivity of hydraulic calcium silicate cements

    PubMed Central

    Niu, Li-na; Jiao, Kai; Wang, Tian-da; Zhang, Wei; Camilleri, Josette; Bergeron, Brian E.; Feng, Hai-lan; Mao, Jing; Chen, Ji-hua; Pashley, David H.; Tay, Franklin R.

    2014-01-01

    Objectives In tissue regeneration research, the term “bioactivity” was initially used to describe the resistance to removal of a biomaterial from host tissues after intraosseous implantation. Hydraulic calcium silicate cements (HCSCs) are putatively accepted as bioactive materials, as exemplified by the increasing number of publications reporting that these cements produce an apatite-rich surface layer after they contact simulated body fluids. Methods In this review, the same definitions employed for establishing in vitro and in vivo bioactivity in glass–ceramics, and the proposed mechanisms involved in these phenomena are used as blueprints for investigating whether HCSCs are bioactive. Results The literature abounds with evidence that HCSCs exhibit in vitro bioactivity; however, there is a general lack of stringent methodologies for characterizing the calcium phosphate phases precipitated on HCSCs. Although in vivo bioactivity has been demonstrated for some HCSCs, a fibrous connective tissue layer is frequently identified along the bone–cement interface that is reminiscent of the responses observed in bioinert materials, without accompanying clarifications to account for such observations. Conclusions As bone-bonding is not predictably achieved, there is insufficient scientific evidence to substantiate that HCSCs are indeed bioactive. Objective appraisal criteria should be developed for more accurately defining the bioactivity profiles of HCSCs designed for clinical use. PMID:24440449

  15. Effect of certain indigenous processing methods on the bioactive compounds of ten different wild type legume grains.

    PubMed

    Vadivel, Vellingiri; Biesalski, Hans K

    2012-12-01

    In recent years, research efforts are under-way on the possibilities of utilization of natural source of bioactive compounds for the dietary management of certain chronic diseases such as diabetes, obesity, cardiovascular diseases, cancer etc. In this connection, seed materials of promising wild type under-utilized food legume grains such as Acacia nilotica (L.) Willd. Ex Delile, Bauhinia purpurea L., Canavalia ensiformis (L.) DC., Cassia hirsuta L., Caesalpinia bonducella F., Erythrina indica L., Mucuna gigantea (Willd.) DC., Pongamia pinnata (L.) Pierre, Sebania sesban (L.) Merr. and Xylia xylocarpa Roxb. Taub., collected from South India, were investigated for certain bioactive compounds. All the samples were found to constitute a viable source of total free phenolics (3.12-6.69g/100g DM), tannins (1.10-4.41g/100g DM), L-Dopa (1.34-5.45g/100g DM) and phytic acid (0.98-3.14g/100g DM). In general, the seed materials of X. xylocarpa recorded high levels of total free phenolics and tannins, whereas the maximum levels of L-Dopa and phytic acid were noticed in M. gigantea and S. sesban, respectively. Further, presently investigated all the bioactive compounds were drastically reduced during soaking in tamarind solution + cooking as well as soaking in alkaline solution + cooking, and thus these treatments were considered to be more aggressive practices. Open-pan roasting also demonstrated a significant reduction of total free phenolics, tannins and moderate loss of L-Dopa and phytic acid. Alternatively, sprouting + oil-frying showed significant level of increase of total free phenolics (9-27%) and tannins (12-28%), but diminishing effect on phytic acid and L-Dopa. Hence, among the presently employed treatments, sprouting + oil-frying could be recommended as a suitable treatment for the versatile utilization of these wild under-utilized legume grains for the dietary management of certain chronic diseases. PMID:24293686

  16. Flexible electronics: Sophisticated skin

    NASA Astrophysics Data System (ADS)

    Bauer, Siegfried

    2013-10-01

    Advances in materials science and layout design have enabled the realization of flexible and multifunctional electronic devices. Two demonstrations of electronic skins, which combine temperature and pressure sensing with integrated thermal actuators and organic displays, unveil the potential of these devices for robotics and clinical applications.

  17. Noninvasive Skin Tightening Treatment.

    PubMed

    Gold, Michael H

    2015-06-01

    Noninvasive skin tightening has become one of the most common cosmetic aesthetic procedures being performed today. The use of radiofrequency devices for these procedures has been at the forefront of this trend for the past several years. Newer and more sophisticated radiofrequency devices are being brought to the market and presented here are the Venus Freeze and Venus Legacy. PMID:26155322

  18. Skin Problems in Construction

    MedlinePLUS

    ... gloves clean and dry. WASH and dry your hands before putting on gloves. CLEAN off the outside of your gloves before ... your gloves when you take them off. DISCARD gloves with holes, tears, or worn areas. Using a hand washing station 3 Keep skin clean Wash with ...

  19. Immunopathology of skin lesions.

    PubMed

    Khan, N; Maheshwari, V; Trivedi, I; Kalam, A

    2001-01-01

    A study was conducted on 130 patients suffering from skin lesions which included psoriasis, lichen planus, DLE, pemphigus, vitiligo and alopecia areata. Forty age-and-sex-matched healthy individuals served as control. Serum IgG, IgM, and circulating immune complexes (CIC) were estimated. Significant increase in serum IgG (1937.2 +/- 1030.43 mg%) and IgM (232.12 +/- 136.98 mg%) was observed in all the skin lesions when compared with controls except in lichen planus where they were significantly lowered, values being 580.61+/- 77.35 mg% and 66.88 +/- 6.59 mg% respectively. CIC levels were significantly raised (P< 0.00 1) in various skin lesions (40.49+/-23.29) when compared with controls (17.68+/- 3.21), but no significance was observed in lichen planus( 17.72 +/- 4.28). Serum IgG, IgM and CIC were statistically significantly altered depending on the extent of the lesion and lowered significantly to almost normal values following treatment, thereby confirming the role of immunity in the pathogenesis of these skin disorders. PMID:17664758

  20. Noninvasive Skin Tightening Treatment

    PubMed Central

    2015-01-01

    Noninvasive skin tightening has become one of the most common cosmetic aesthetic procedures being performed today. The use of radiofrequency devices for these procedures has been at the forefront of this trend for the past several years. Newer and more sophisticated radiofrequency devices are being brought to the market and presented here are the Venus Freeze and Venus Legacy. PMID:26155322

  1. Cytokines and the Skin Barrier

    PubMed Central

    Hnel, Kai H.; Cornelissen, Christian; Lscher, Bernhard; Baron, Jens Malte

    2013-01-01

    The skin is the largest organ of the human body and builds a barrier to protect us from the harmful environment and also from unregulated loss of water. Keratinocytes form the skin barrier by undergoing a highly complex differentiation process that involves changing their morphology and structural integrity, a process referred to as cornification. Alterations in the epidermal cornification process affect the formation of the skin barrier. Typically, this results in a disturbed barrier, which allows the entry of substances into the skin that are immunologically reactive. This contributes to and promotes inflammatory processes in the skin but also affects other organs. In many common skin diseases, including atopic dermatitis and psoriasis, a defect in the formation of the skin barrier is observed. In these diseases the cytokine composition within the skin is different compared to normal human skin. This is the result of resident skin cells that produce cytokines, but also because additional immune cells are recruited. Many of the cytokines found in defective skin are able to influence various processes of differentiation and cornification. Here we summarize the current knowledge on cytokines and their functions in healthy skin and their contributions to inflammatory skin diseases. PMID:23531535

  2. The Role of the Skin Barrier in Occupational Skin Diseases.

    PubMed

    Kasemsarn, Pranee; Bosco, Joanna; Nixon, Rosemary L

    2016-01-01

    Occupational skin diseases (OSDs) are the second most common occupational diseases worldwide. Occupational contact dermatitis (OCD) is the most frequent OSD, and comprises irritant contact dermatitis (ICD), allergic contact dermatitis (ACD), contact urticaria and protein contact dermatitis. There are many endogenous and exogenous factors which affect the development of OCD, including age, sex, ethnicity, atopic skin diathesis, certain occupations and environmental factors. One of the most important contributing causes is skin barrier dysfunction. The skin provides a first-line defense from environmental assaults and incorporates physical, chemical and biological protection. Skin barrier disturbance plays a crucial role in various skin diseases such as atopic dermatitis (AD), ichthyosis, ICD and ACD. Genetic factors, such as filaggrin gene (FLG) mutations, and external factors, such as skin irritants interfering with stratum corneum structure and composition, may lead to abnormalities in skin barrier function and increased vulnerability to skin diseases. FLG encodes the cornified envelope protein, filaggrin, which is involved in skin barrier function. FLG mutation is associated with the development of OCD. High-risk occupations for OCD include health care workers, hairdressers and construction workers. There are often multiple contributing causes to OCD, as workers are exposed to both irritants and allergens. AD is also associated with skin barrier disruption and plays an important role in OCD. ICD often precedes and facilitates the development of ACD, with impairment of the skin barrier contributing to the concurrence of ICD and ACD in many workers with OCD. PMID:26844905

  3. Reprint of: Review of bioactive glass: From Hench to hybrids.

    PubMed

    Jones, Julian R

    2015-09-01

    Bioactive glasses are reported to be able to stimulate more bone regeneration than other bioactive ceramics but they lag behind other bioactive ceramics in terms of commercial success. Bioactive glass has not yet reached its potential but research activity is growing. This paper reviews the current state of the art, starting with current products and moving onto recent developments. Larry Hench's 45S5 Bioglass® was the first artificial material that was found to form a chemical bond with bone, launching the field of bioactive ceramics. In vivo studies have shown that bioactive glasses bond with bone more rapidly than other bioceramics, and in vitro studies indicate that their osteogenic properties are due to their dissolution products stimulating osteoprogenitor cells at the genetic level. However, calcium phosphates such as tricalcium phosphate and synthetic hydroxyapatite are more widely used in the clinic. Some of the reasons are commercial, but others are due to the scientific limitations of the original Bioglass 45S5. An example is that it is difficult to produce porous bioactive glass templates (scaffolds) for bone regeneration from Bioglass 45S5 because it crystallizes during sintering. Recently, this has been overcome by understanding how the glass composition can be tailored to prevent crystallization. The sintering problems can also be avoided by synthesizing sol-gel glass, where the silica network is assembled at room temperature. Process developments in foaming, solid freeform fabrication and nanofibre spinning have now allowed the production of porous bioactive glass scaffolds from both melt- and sol-gel-derived glasses. An ideal scaffold for bone regeneration would share load with bone. Bioceramics cannot do this when the bone defect is subjected to cyclic loads, as they are brittle. To overcome this, bioactive glass polymer hybrids are being synthesized that have the potential to be tough, with congruent degradation of the bioactive inorganic and the polymer components. Key to this is creating nanoscale interpenetrating networks, the organic and inorganic components of which have covalent coupling between them, which involves careful control of the chemistry of the sol-gel process. Bioactive nanoparticles can also now be synthesized and their fate tracked as they are internalized in cells. This paper reviews the main developments in the field of bioactive glass and its variants, covering the importance of control of hierarchical structure, synthesis, processing and cellular response in the quest for new regenerative synthetic bone grafts. The paper takes the reader from Hench's Bioglass 45S5 to new hybrid materials that have tailorable mechanical properties and degradation rates. PMID:26235346

  4. Thoracodorsal artery perforator flap: Indeed a versatile flap

    PubMed Central

    Jain, Leena; Kumta, Samir M.; Purohit, Shrirang K.; Raut, Rashmi

    2015-01-01

    Introduction: The thoracodorsal artery perforator (TDAP) flap has emerged as one of the ideal perforator flaps. We, hereby, describe its versatility in indications (free/pedicled), methods of harvest (patient position and paddle orientation) and perforator consistency. Materials and Methods: We have performed a total of six TDAP flaps-five free and one pedicled, over a period of 1-year from March 2014 to February 2015 at a single centre. Our indications have been: Reconstruction of oral cavity, breast and upper and lower extremities. Results: We had neither any failures nor any re-explorations. The average perforator length is about 6 cm and the pedicle length can be extended to 12-14 cm by including the thoracodorsal artery. There is inconsistency in perforator position; however, the presence of a perforator is certain. It can be harvested in lateral, prone or supine position, thus, does not require any position change allowing a two-team approach to reconstruction. The paddle can be oriented vertically or horizontally, both healing with scars in inconspicuous locations. Apart from providing a good colour match for extremities, this flap can be thinned primarily. Conclusion: The versatility of TDAP has several advantages that make it a workhorse flap for most reconstructions requiring soft tissue cover. Further, the ease of harvest makes it a good perforator flap for beginners. Its use in chimerism with the underlying latissimus dorsi muscle provides reconstruction for coverage and volume replacement. PMID:26424978

  5. Robust and versatile pectin-based drug delivery systems.

    PubMed

    Marras-Marquez, T; Pea, J; Veiga-Ochoa, M D

    2015-02-20

    Pectin-based resistant, interactive and versatile hydrogel vehicles for oral administration have been prepared. These systems are thought to be versatile enough to allow the inclusion of substances (such as the surfactants tested: Pluronic, Tween, Na Lauryl sulphate) that may contribute to tailor the drug release patterns. Tolbutamide, that shows a discrete and pH-dependent solubility in water, has been employed as a model drug to test the capability of these matrices to overcome such drug-imposed restraints. The incorporation of different surfactants produced pectin-based hydrogels of difficult manipulation. In order to improve this drawback, two different strategies have been developed: blending with agarose or freeze-drying. The presence of agarose yields robust systems that can be handled and tested as prepared, in the fresh state. Freeze-drying not only allows to shape pure pectin and blend systems, but also generates a porous structure whose microstructure, determined by the different components included, influences on the drug release behavior. Tolbutamide release kinetics from freshly prepared matrices can be fitted to the Higuchi model while the freeze-dried ones adjust to the Korsmeyer-Peppas model; hence the hydrogel chains rearrangement processes rule the release during the rehydration process. PMID:25542990

  6. Versatile clinical information system design for emergency departments.

    PubMed

    Amouh, Teh; Gemo, Monica; Macq, Benoît; Vanderdonckt, Jean; El Gariani, Abdul Wahed; Reynaert, Marc S; Stamatakis, Lambert; Thys, Frédéric

    2005-06-01

    Compared to other hospital units, the emergency department presents some distinguishing characteristics of its own. Emergency health-care delivery is a collaborative process involving the contribution of several individuals who accomplish their tasks while working autonomously under pressure and sometimes with limited resources. Effective computerization of the emergency department information system presents a real challenge due to the complexity of the scenario. Current computerized support suffers from several problems, including inadequate data models, clumsy user interfaces, and poor integration with other clinical information systems. To tackle such complexity, we propose an approach combining three points of view, namely the transactions (in and out of the department), the (mono and multi) user interfaces and data management. Unlike current systems, we pay particular attention to the user-friendliness and versatility of our system. This means that intuitive user interfaces have been conceived and specific software modeling methodologies have been applied to provide our system with the flexibility and adaptability necessary for the individual and group coordinated tasks. Our approach has been implemented by prototyping a web-based, multiplatform, multiuser, and versatile clinical information system built upon multitier software architecture, using the Java programming language. PMID:16138534

  7. Versatile optical coherence tomography for imaging the human eye.

    PubMed

    Tao, Aizhu; Shao, Yilei; Zhong, Jianguang; Jiang, Hong; Shen, Meixiao; Wang, Jianhua

    2013-07-01

    We demonstrated the feasibility of a CMOS-based spectral domain OCT (SD-OCT) for versatile ophthalmic applications of imaging the corneal epithelium, limbus, ocular surface, contact lens, crystalline lens, retina, and full eye in vivo. The system was based on a single spectrometer and an alternating reference arm with four mirrors. A galvanometer scanner was used to switch the reference beam among the four mirrors, depending on the imaging application. An axial resolution of 7.7 ?m in air, a scan depth of up to 37.7 mm in air, and a scan speed of up to 70,000 A-lines per second were achieved. The approach has the capability to provide high-resolution imaging of the corneal epithelium, contact lens, ocular surface, and tear meniscus. Using two reference mirrors, the zero delay lines were alternatively placed on the front cornea or on the back lens. The entire ocular anterior segment was imaged by registering and overlapping the two images. The full eye through the pupil was measured when the reference arm was switched among the four reference mirrors. After mounting a 60 D lens in the sample arm, this SD-OCT was used to image the retina, including the macula and optical nerve head. This system demonstrates versatility and simplicity for multi-purpose ophthalmic applications. PMID:23847729

  8. Versatile Low Level RF System For Linear Accelerators

    NASA Astrophysics Data System (ADS)

    Potter, James M.

    2011-06-01

    The Low Level RF (LLRF) system is the source of all of the rf signals required for an rf linear accelerator. These signals are amplified to drive accelerator and buncher cavities. It can even provide the synchronizing signal for the rf power for a synchrotron. The use of Direct Digital Synthesis (DDS) techniques results in a versatile system that can provide multiple coherent signals at the same or different frequencies with adjustable amplitudes and phase relations. Pulsing the DDS allows rf switching with an essentially infinite on/off ratio. The LLRF system includes a versatile phase detector that allows phase-locking the rf frequency to a cavity at any phase angle over the full 360 range. With the use of stepper motor driven slug tuners multiple cavity resonant frequencies can be phase locked to the rf source frequency. No external phase shifters are required and there is no feedback loop phase setup required. All that is needed is to turn the frequency feedback on. The use of Digital Signal Processing (DSP) allows amplitude and phase control over the entire rf pulse. This paper describes the basic principles of a LLRF system that has been used for both proton accelerators and electron accelerators, including multiple tank accelerators, sub-harmonic and fundamental bunchers, and synchrotrons.

  9. Versatile Aggressive Mimicry of Cicadas by an Australian Predatory Katydid

    PubMed Central

    Marshall, David C.; Hill, Kathy B. R.

    2009-01-01

    Background In aggressive mimicry, a predator or parasite imitates a signal of another species in order to exploit the recipient of the signal. Some of the most remarkable examples of aggressive mimicry involve exploitation of a complex signal-response system by an unrelated predator species. Methodology/Principal Findings We have found that predatory Chlorobalius leucoviridis katydids (Orthoptera: Tettigoniidae) can attract male cicadas (Hemiptera: Cicadidae) by imitating the species-specific wing-flick replies of sexually receptive female cicadas. This aggressive mimicry is accomplished both acoustically, with tegminal clicks, and visually, with synchronized body jerks. Remarkably, the katydids respond effectively to a variety of complex, species-specific Cicadettini songs, including songs of many cicada species that the predator has never encountered. Conclusions/Significance We propose that the versatility of aggressive mimicry in C. leucoviridis is accomplished by exploiting general design elements common to the songs of many acoustically signaling insects that use duets in pair-formation. Consideration of the mechanism of versatile mimicry in C. leucoviridis may illuminate processes driving the evolution of insect acoustic signals, which play a central role in reproductive isolation of populations and the formation of species. PMID:19142230

  10. Versatile Low Level RF System For Linear Accelerators

    SciTech Connect

    Potter, James M.

    2011-06-01

    The Low Level RF (LLRF) system is the source of all of the rf signals required for an rf linear accelerator. These signals are amplified to drive accelerator and buncher cavities. It can even provide the synchronizing signal for the rf power for a synchrotron. The use of Direct Digital Synthesis (DDS) techniques results in a versatile system that can provide multiple coherent signals at the same or different frequencies with adjustable amplitudes and phase relations. Pulsing the DDS allows rf switching with an essentially infinite on/off ratio. The LLRF system includes a versatile phase detector that allows phase-locking the rf frequency to a cavity at any phase angle over the full 360 deg. range. With the use of stepper motor driven slug tuners multiple cavity resonant frequencies can be phase locked to the rf source frequency. No external phase shifters are required and there is no feedback loop phase setup required. All that is needed is to turn the frequency feedback on. The use of Digital Signal Processing (DSP) allows amplitude and phase control over the entire rf pulse. This paper describes the basic principles of a LLRF system that has been used for both proton accelerators and electron accelerators, including multiple tank accelerators, sub-harmonic and fundamental bunchers, and synchrotrons.

  11. Robust and versatile ionic liquid microarrays achieved by microcontact printing.

    PubMed

    Gunawan, Christian A; Ge, Mengchen; Zhao, Chuan

    2014-01-01

    Lab-on-a-chip and miniaturized systems have gained significant popularity motivated by marked differences in material performance at the micro-to-nano-scale realm. However, to fully exploit micro-to-nano-scale chemistry, solvent volatility and lack of reproducibility need to be overcome. Here, we combine the non-volatile and versatile nature of ionic liquids with microcontact printing in an attempt to establish a facile protocol for high throughput fabrication of open microreactors and microfluidics. The micropatterned ionic liquid droplets have been demonstrated as electrochemical cells and reactors for microfabrication of metals and charge transfer complexes, substrates for immobilization of proteins and as membrane-free high-performance amperometric gas sensor arrays. The results suggest that miniaturized ionic liquid systems can be used to solve the problems of solvent volatility and slow mass transport in viscous ionic liquids in lab-on-a-chip devices, thus providing a versatile platform for a diverse number of applications. PMID:24781644

  12. A new method for skin color enhancement

    NASA Astrophysics Data System (ADS)

    Zeng, Huanzhao; Luo, Ronnier

    2012-01-01

    Skin tone is the most important color category in memory colors. Reproducing it pleasingly is an important factor in photographic color reproduction. Moving skin colors toward their preferred skin color center improves the skin color preference on photographic color reproduction. Two key factors to successfully enhance skin colors are: a method to detect original skin colors effectively even if they are shifted far away from the regular skin color region, and a method to morph skin colors toward a preferred skin color region properly without introducing artifacts. A method for skin color enhancement presented by the authors in the same conference last year applies a static skin color model for skin color detection, which may miss to detect skin colors that are far away from regular skin tones. In this paper, a new method using the combination of face detection and statistical skin color modeling is proposed to effectively detect skin pixels and to enhance skin colors more effectively.

  13. Improved electrodes for skin contacts

    NASA Technical Reports Server (NTRS)

    Castle, J. G.; Lattanzi, R. R.

    1972-01-01

    Design is described of thick, flexible electrodes with appropriate metal surfaces which prevent unnecessary skin motion. Electrodes provide sufficient radial pressure directed toward body surface to depress skin a noticeable portion of its normal resilient thickness.

  14. Skin Cancer: Signs and Symptoms

    MedlinePLUS

    ... skin cancer appears in many shapes and sizes. Squamous cell carcinoma (SCC) This is a very common type of ... lip; skin on the lip can get thick Squamous cell carcinoma . These patients all have forms of squamous cell ...

  15. Dry skin - self-care

    MedlinePLUS

    ... or showers frequently Washing your hands often Some soaps and detergents Skin conditions, such as eczema and ... apply your moisturizer. Avoid skin care products and soaps that contain alcohol, fragrances, dyes, or other chemicals. ...

  16. Sun Safety: Save Your Skin

    MedlinePLUS Videos and Cool Tools

    ... against all types of skin damage caused by sunlight water resistance—sunscreen that stays on your skin ... go out. back to top Protect the Eyes Sunlight reflecting off snow, sand, or water further increases ...

  17. Skin - abnormally dark or light

    MedlinePLUS

    ... as tinea versicolor) Pityriasis alba Vitiligo Certain medicines Skin condition called idiopathic guttate hyomelanosis ... surgery, or phototherapy, depending on the type of skin condition you have. Bleaching creams can help lighten dark ...

  18. Tissue Engineered Human Skin Equivalents

    PubMed Central

    Zhang, Zheng; Michniak-Kohn, Bozena B.

    2012-01-01

    Human skin not only serves as an important barrier against the penetration of exogenous substances into the body, but also provides a potential avenue for the transport of functional active drugs/reagents/ingredients into the skin (topical delivery) and/or the body (transdermal delivery). In the past three decades, research and development in human skin equivalents have advanced in parallel with those in tissue engineering and regenerative medicine. The human skin equivalents are used commercially as clinical skin substitutes and as models for permeation and toxicity screening. Several academic laboratories have developed their own human skin equivalent models and applied these models for studying skin permeation, corrosivity and irritation, compound toxicity, biochemistry, metabolism and cellular pharmacology. Various aspects of the state of the art of human skin equivalents are reviewed and discussed. PMID:24300178

  19. Three-dimensional chemical imaging of skin using stimulated Raman scattering microscopy

    NASA Astrophysics Data System (ADS)

    Drutis, Dane M.; Hancewicz, Thomas M.; Pashkovski, Eugene; Feng, Lin; Mihalov, Dawn; Holtom, Gary; Ananthapadmanabhan, Kavssery P.; Xie, X. Sunney; Misra, Manoj

    2014-11-01

    Stimulated Raman scattering (SRS) microscopy is used to generate structural and chemical three-dimensional images of native skin. We employed SRS microscopy to investigate the microanatomical features of skin and penetration of topically applied materials. Image depth stacks are collected at distinct wavelengths corresponding to vibrational modes of proteins, lipids, and water in the skin. We observed that corneocytes in stratum corneum are grouped together in clusters, 100 to 250 ?m in diameter, separated by 10- to 25-?m-wide microanatomical skin-folds called canyons. These canyons occasionally extend down to depths comparable to that of the dermal-epidermal junction below the flat surface regions in porcine and human skin. SRS imaging shows the distribution of chemical species within cell clusters and canyons. Water is predominately located within the cell clusters, and its concentration rapidly increases at the transition from stratum corneum to viable epidermis. Canyons do not contain detectable levels of water and are rich in lipid material. Oleic acid-d34 applied to the skin surface lines the canyons down to a depth of 50 ?m below the surface of the skin. This observation could have implications on the evaluation of penetration profiles of bioactive materials measured using traditional methods, such as tape-stripping.

  20. Parallel peptidome and transcriptome analyses of amphibian skin secretions using archived frozen acid-solvated samples.

    PubMed

    Bai, Bing; Zhang, Yingqi; Wang, Hui; Zhou, Mei; Yu, Yang; Ding, Sijia; Chen, Tianbao; Wang, Lei; Shaw, Chris

    2013-06-01

    Amphibian skin secretions are unique sources of bioactive peptides and their donor species are currently rapidly disappearing from the biosphere. Here, we report that both peptides and polyadenylated mRNAs from skin granular glands remain amenable to study in samples of stimulated skin secretions following their storage in 0.1% aqueous trifluoroacetic acid at -20C for many years. Frozen acidified solutions of toad (Bombina variegata) skin secretions, stored for 12years, were thawed and samples removed for direct reverse phase HPLC fractionation. Additional samples were removed, snap frozen and lyophilised for construction of cDNA libraries following polyadenylated mRNA capture using magnetic oligo-dT beads and reverse transcription. Using the bombesin and bradykinin peptides found in bombinid toad skin as models, individual variant peptides of each type were located in reverse phase HPLC fractions and their corresponding biosynthetic precursor-encoding mRNA transcripts were cloned from the cDNA library using a RACE PCR strategy. This study illustrates unequivocally that both amphibian skin secretion peptides and their biosynthetic precursor-encoding polyadenylated mRNAs are stable in frozen acid-solvated skin secretion samples for considerable periods of time-a finding that may have fundamental implications in the study of archived materials but also in the wider field of molecular biology. PMID:22573142

  1. In Vitro Bioactivity and Antimicrobial Tuning of Bioactive Glass Nanoparticles Added with Neem (Azadirachta indica) Leaf Powder

    PubMed Central

    Prabhu, M.; Ruby Priscilla, S.; Kavitha, K.; Manivasakan, P.; Rajendran, V.; Kulandaivelu, P.

    2014-01-01

    Silica and phosphate based bioactive glass nanoparticles (58SiO2-33CaO-9P2O5) with doping of neem (Azadirachta indica) leaf powder and silver nanoparticles were prepared and characterised. Bioactive glass nanoparticles were produced using sol-gel technique. In vitro bioactivity of the prepared samples was investigated using simulated body fluid. X-ray diffraction (XRD) pattern of prepared glass particles reveals amorphous phase and spherical morphology with a particle size of less than 50?nm. When compared to neem doped glass, better bioactivity was attained in silver doped glass through formation of hydroxyapatite layer on the surface, which was confirmed through XRD, Fourier transform infrared (FTIR), and scanning electron microscopy (SEM) analysis. However, neem leaf powder doped bioactive glass nanoparticles show good antimicrobial activity against Staphylococcus aureus and Escherichia coli and less bioactivity compared with silver doped glass particles. In addition, the biocompatibility of the prepared nanocomposites reveals better results for neem doped and silver doped glasses at lower concentration. Therefore, neem doped bioactive glass may act as a potent antimicrobial agent for preventing microbial infection in tissue engineering applications. PMID:25276834

  2. Not miR-ly micromanagers: the functions and regulatory networks of miRNAs in mammalian skin

    PubMed Central

    Riemondy, Kent; Hoefert, Jaimee E

    2014-01-01

    The microRNA (miRNA) pathway is a widespread mechanism of post-transcriptional gene regulation in eukaryotic cells. In animals, each miRNA species can regulate hundreds of protein coding genes, resulting in pervasive functions for miRNAs in numerous cellular processes. Since the identification of the first mammalian miRNA, the function of miRNAs in mammals has been a topic of great interest, both because of the versatile roles of miRNAs in biological systems, as well as the clinical potential of these regulatory RNAs. With well-defined cell lineages and the availability of versatile tools for both in vivo and in vitro studies, mammalian skin has emerged as an important system in which to examine miRNAs functions in adult tissues. In this review, we discuss recent insights into the functions and regulatory networks of miRNAs in mammals, with a specific focus on murine skin development as a model system. We first introduce functional analyses of the miRNA biogenesis pathway in the skin, then highlight the functions of individual miRNAs in skin development, followed by an examination of miRNA roles in skin stress responses. We finish with a discussion of miRNA regulatory networks and emphasize future challenges and emerging technologies that permit the genome-wide study of miRNA functions and regulatory mechanisms in mammalian skin. PMID:25044412

  3. Laser microporation of the skin: prospects for painless application of protective and therapeutic vaccines

    PubMed Central

    Scheiblhofer, Sandra; Thalhamer, Josef; Weiss, Richard

    2013-01-01

    Introduction: In contrast to muscle and subcutaneous tissue, the skin is easily accessible and provides unique immunological properties. Increasing knowledge about the complex interplay of skin-associated cell types in the development of cutaneous immune responses has fueled efforts to target the skin for vaccination as well as for immunotherapy. Areas covered: This review provides an overview on skin layers and their resident immunocompetent cell types. Advantages and shortcomings of standard methods and innovative technologies to circumvent the outermost skin barrier are addressed. Studies employing fractional skin ablation by infrared lasers for cutaneous delivery of drugs, as well as high molecular weight molecules such as protein antigens or antibodies, are reviewed, and laserporation is introduced as a versatile transcutaneous vaccination platform. Specific targeting of the epidermis or the dermis by different laser settings, the resulting kinetics of uptake and transport and the immune response types elicited are discussed, and the potential of this transcutaneous delivery platform for allergen-specific immunotherapy is demonstrated. Expert opinion: Needle-free and painless vaccination approaches have the potential to replace standard methods due to their improved safety and optimal patient compliance. The use of fractional laser devices for stepwise ablation of skin layers might be advantageous for both vaccination against microbial pathogens, as well as immunotherapeutic approaches, such as allergen-specific immunotherapy. Thorough investigation of the underlying immunological mechanisms will help to provide the knowledge for a rational design of transcutaneous protective/therapeutic vaccines. PMID:23425032

  4. Brain-Skin Connection: Stress, Inflammation and Skin Aging

    PubMed Central

    Chen, Ying; Lyga, John

    2014-01-01

    The intricate relationship between stress and skin conditions has been documented since ancient times. Recent clinical observations also link psychological stress to the onset or aggravation of multiple skin diseases. However, the exact underlying mechanisms have only been studied and partially revealed in the past 20 years or so. In this review, the authors will discuss the recent discoveries in the field of “Brain-Skin Connection”, summarizing findings from the overlapping fields of psychology, endocrinology, skin neurobiology, skin inflammation, immunology, and pharmacology. PMID:24853682

  5. Skin Cancers of the Feet

    MedlinePLUS

    ... resemble non-cancerous skin tumors or benign ulcers. Squamous Cell Carcinoma : Squamous cell carcinoma is the most common form of cancer on ... skin of the feet. Most types of early squamous cell carcinoma are confined to the skin and do not ...

  6. [Skin manifestations of monoclonal gammopathies].

    PubMed

    Hello, M; Barbarot, S; Néel, A; Connault, J; Graveleau, J; Durant, C; Decaux, O; Hamidou, M

    2014-01-01

    Whatever their aetiology, monoclonal gammopathies can be associated to several clinical features. Mechanisms are various and sometimes unknown. Skin is frequently involved and may represent a challenging diagnosis. Indeed, skin manifestations are either the presenting features and isolated, or at the background of a systemic syndrome. Our objective was to review the various skin manifestations that have been associated with monoclonal gammopathies. PMID:24070793

  7. Gram stain of skin lesion

    MedlinePLUS

    A skin or mucosal culture may be done along with this test. Other studies are often done on a skin sample to determine if cancer is present. Viral skin lesions like herpes simplex are examined by other tests or a viral culture.

  8. Polyamines and nonmelanoma skin cancer.

    PubMed

    Gilmour, Susan K

    2007-11-01

    Elevated levels of polyamines have long been associated with skin tumorigenesis. Tightly regulated metabolism of polyamines is critical for cell survival and normal skin homeostasis, and these controls are dysregulated in skin tumorigenesis. A key enzyme in polyamine biosynthesis, ornithine decarboxylase (ODC) is upregulated in skin tumors compared to normal skin. Use of transgenic mouse models has demonstrated that polyamines play an essential role in the early promotional phase of skin tumorigenesis. The formation of skin tumors in these transgenic mice is dependent upon polyamine biosynthesis, especially putrescine, since treatment with inhibitors of ODC activity blocks the formation of skin tumors and causes the rapid regression of existing tumors. Although the mechanism by which polyamines promote skin tumorigenesis are not well understood, elevated levels of polyamines have been shown to stimulate epidermal proliferation, alter keratinocyte differentiation status, increase neovascularization, and increase synthesis of extracellular matrix proteins in a manner similar to that seen in wound healing. It is becoming increasingly apparent that elevated polyamine levels activate not only epidermal cells but also underlying stromal cells in the skin to promote the development and progression of skin tumors. The inhibition of polyamine biosynthesis has potential to be an effective chemoprevention strategy for nonmelanoma skin cancer. PMID:17234230

  9. Skin Pedagogies and Abject Bodies

    ERIC Educational Resources Information Center

    Kenway, Jane; Bullen, Elizabeth

    2011-01-01

    How does the beauty industry "narrate the skin"? What does it teach women from different cultural groups about the female body? How does skin function as a site where female subjection and abjection are produced and reproduced? In this paper we examine the skin industry pointing to its extreme commodification of the female body and to the

  10. Skin Pedagogies and Abject Bodies

    ERIC Educational Resources Information Center

    Kenway, Jane; Bullen, Elizabeth

    2011-01-01

    How does the beauty industry "narrate the skin"? What does it teach women from different cultural groups about the female body? How does skin function as a site where female subjection and abjection are produced and reproduced? In this paper we examine the skin industry pointing to its extreme commodification of the female body and to the…

  11. Physiological skin changes during pregnancy.

    PubMed

    Tyler, Kelly H

    2015-03-01

    Physicians may often mistake normal physiological skin changes in pregnancy for pathologic changes, so being able to recognize the skin manifestations unique to pregnancy is of the utmost importance to avoid unnecessary testing and stress for the obstetric patient. Most physiological skin changes will resolve postpartum, so reassurance and expectant management is indicated in almost all cases. PMID:25517755

  12. Polyamines and nonmelanoma skin cancer

    SciTech Connect

    Gilmour, Susan K.

    2007-11-01

    Elevated levels of polyamines have long been associated with skin tumorigenesis. Tightly regulated metabolism of polyamines is critical for cell survival and normal skin homeostasis, and these controls are dysregulated in skin tumorigenesis. A key enzyme in polyamine biosynthesis, ornithine decarboxylase (ODC) is upregulated in skin tumors compared to normal skin. Use of transgenic mouse models has demonstrated that polyamines play an essential role in the early promotional phase of skin tumorigenesis. The formation of skin tumors in these transgenic mice is dependent upon polyamine biosynthesis, especially putrescine, since treatment with inhibitors of ODC activity blocks the formation of skin tumors and causes the rapid regression of existing tumors. Although the mechanism by which polyamines promote skin tumorigenesis are not well understood, elevated levels of polyamines have been shown to stimulate epidermal proliferation, alter keratinocyte differentiation status, increase neovascularization, and increase synthesis of extracellular matrix proteins in a manner similar to that seen in wound healing. It is becoming increasingly apparent that elevated polyamine levels activate not only epidermal cells but also underlying stromal cells in the skin to promote the development and progression of skin tumors. The inhibition of polyamine biosynthesis has potential to be an effective chemoprevention strategy for nonmelanoma skin cancer.

  13. Atropisomeric small molecule Bcl-2 ligands: determination of bioactive conformation.

    PubMed

    Porter, John; Payne, Andrew; Whitcombe, Ian; de Candole, Ben; Ford, Daniel; Garlish, Rachel; Hold, Adam; Hutchinson, Brian; Trevitt, Graham; Turner, James; Edwards, Chloe; Watkins, Clare; Davis, Jeremy; Stubberfield, Colin

    2009-03-15

    The separation of atropisomeric conformers of 1,2,3,4-tetrahydroisoquinoline amide Bcl-2 ligands allowed the identification of the bioactive conformer which was subsequently confirmed by X-ray crystallography. PMID:19217289

  14. Identifying bioactive components in natural products through chromatographic fingerprint.

    PubMed

    Xu, Jian; Xu, Qing-Song; Chan, Chi-On; Mok, Daniel Kam-Wah; Yi, Lun-Zhao; Chau, Foo-Tim

    2015-04-22

    Bioactive component identification is a crucial issue in search for new drug leads. We provide a new strategy to search for bioactive components based on Sure Independence Screening (SIS) and interval PLS (iPLS). The method, which is termed as SIS-iPLS, is not only able to find out the chief bioactive components, but also able to judge how many components should be there responsible for the total bioactivity. The method is totally "data-driven" with no need for prior knowledge about the unknown mixture analyzed, therefore especially suitable for effect-directed work like bioassay-guided fractionation. Two data sets, a synthetic mixture system of twelve components and a suite of Radix Puerariae Lobatae extracts samples, are used to test the identification ability of the SIS-iPLS method. PMID:25819786

  15. Current Strategies to Improve the Bioactivity of PEEK

    PubMed Central

    Ma, Rui; Tang, Tingting

    2014-01-01

    The synthetic thermoplastic polymer polyetheretherketone (PEEK) is becoming a popular component of clinical orthopedic and spinal applications, but its practical use suffers from several limitations. Although PEEK is biocompatible, chemically stable, radiolucent and has an elastic modulus similar to that of normal human bone, it is biologically inert, preventing good integration with adjacent bone tissues upon implantation. Recent efforts have focused on increasing the bioactivity of PEEK to improve the bone-implant interface. Two main strategies have been used to overcome the inert character of PEEK. One approach is surface modification to activate PEEK through surface treatment alone or in combination with a surface coating. Another strategy is to prepare bioactive PEEK composites by impregnating bioactive materials into PEEK substrate. Researchers believe that modified bioactive PEEK will have a wide range of orthopedic applications. PMID:24686515

  16. Industrial-scale manufacturing of pharmaceutical-grade bioactive peptides.

    PubMed

    Agyei, Dominic; Danquah, Michael K

    2011-01-01

    Recent studies have shown that most peptide sequences encrypted in food proteins confer bioactive properties after release by enzymatic hydrolysis. Such bioactivities, which include antithrombotic, antihypertensive, immunomodulatory and antioxidant properties, are among the traits that are of biological significance in therapeutic products. Bioactive peptides could therefore serve as potential therapeutic agents. Moreover, research has shown that peptide therapeutics are toxicologically safe, and present less side effects when compared to small molecule drugs. However, the major conventional methods i.e. the synthetic and biotechnological methods used in the production of peptide therapeutics are relatively expensive. The lack of commercially-viable processes for large-scale production of peptide therapeutics has therefore been a major hindrance to the application of peptides as therapeutic aids. This paper therefore discusses the plausibility of manufacturing pharmaceutical-grade bioactive peptides from food proteins; the challenges and some implementable strategies for overcoming those challenges. PMID:21238564

  17. Bioactive ceramic-reinforced composites for bone augmentation

    PubMed Central

    Tanner, K. E.

    2010-01-01

    Biomaterials have been used to repair the human body for millennia, but it is only since the 1970s that man-made composites have been used. Hydroxyapatite (HA)-reinforced polyethylene (PE) is the first of the ‘second-generation’ biomaterials that have been developed to be bioactive rather than bioinert. The mechanical properties have been characterized using quasi-static, fatigue, creep and fracture toughness testing, and these studies have allowed optimization of the production method. The in vitro and in vivo biological properties have been investigated with a range of filler content and have shown that the presence of sufficient bioactive filler leads to a bioactive composite. Finally, the material has been applied clinically, initially in the orbital floor and later in the middle ear. From this initial combination of HA in PE other bioactive ceramic polymer composites have been developed. PMID:20591846

  18. Exploitation of phage battery in the search for bioactive actinomycetes.

    PubMed

    Kurtbke, D Ipek

    2011-02-01

    Screening of microbial natural products continues to represent an important route to the discovery of novel bioactive compounds for the development of new therapeutic agents, and actinomycetes are still the major producers of biopharmaceuticals. Selective isolation of bioactive actinomycete species, in particular the rare ones, has thus become a target for industrial microbiologists. In this context, bacteriophages have proven to be useful tools as (1) naturally present indicators of under-represented or rare actinomycete taxa in environmental samples, (2) indicators of the relatedness of bioactive taxa in target-directed search and discovery, (3) de-selection agents of unwanted taxa on isolation plates in target-specific search for rare actinomycete taxa, (4) tools in screening assays for specific targets. Against this background, a number of case studies are presented to illustrate the use of bacteriophages as tools in actinomycete-origin bioactive compound search and discovery programs. PMID:21120467

  19. Bioactive phytochemicals in wheat: Extraction, analysis, processing, and functional properties

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Whole wheat provides a rich source of bioactive phytochemicals namely, phenolic acids, carotenoids, tocopherols, alkylresorcinols, arabinoxylans, benzoxazinoids, phytosterols, and lignans. This review provides information on the distribution, extractability, analysis, and nutraceutical properties of...

  20. Marine actinobacteria: an important source of bioactive natural products.

    PubMed

    Manivasagan, Panchanathan; Kang, Kyong-Hwa; Sivakumar, Kannan; Li-Chan, Eunice C Y; Oh, Hyun-Myung; Kim, Se-Kwon

    2014-07-01

    Marine environment is largely an untapped source for deriving actinobacteria, having potential to produce novel, bioactive natural products. Actinobacteria are the prolific producers of pharmaceutically active secondary metabolites, accounting for about 70% of the naturally derived compounds that are currently in clinical use. Among the various actinobacterial genera, Actinomadura, Actinoplanes, Amycolatopsis, Marinispora, Micromonospora, Nocardiopsis, Saccharopolyspora, Salinispora, Streptomyces and Verrucosispora are the major potential producers of commercially important bioactive natural products. In this respect, Streptomyces ranks first with a large number of bioactive natural products. Marine actinobacteria are unique enhancing quite different biological properties including antimicrobial, anticancer, antiviral, insecticidal and enzyme inhibitory activities. They have attracted global in the last ten years for their ability to produce pharmaceutically active compounds. In this review, we have focused attention on the bioactive natural products isolated from marine actinobacteria, possessing unique chemical structures that may form the basis for synthesis of novel drugs that could be used to combat resistant pathogenic microorganisms. PMID:24959957

  1. History and trends of bioactive glass-ceramics.

    PubMed

    Montazerian, Maziar; Dutra Zanotto, Edgar

    2016-05-01

    The interest around bioactive glass-ceramics (GCs) has grown significantly over the last two decades due to their appropriate biochemical and mechanical properties. The intense research effort in this field has led to some new commercial products for biomedical applications. This review article begins with the basic concepts of GC processing and development via controlled heat treatments of monolithic pieces or sinter-crystallization of powdered glasses. We then go on to describe the processing, properties, and applications of some commercial bioactive GCs and discuss selected valuable reported researches on several promising types of bioactive GCs. The article finishes with a section on open relevant research directions for bioactive GC development. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 104A: 1231-1249, 2016. PMID:26707951

  2. Bioactive and Biodegradable Nanocomposites and Hybrid Biomaterials for Bone Regeneration

    PubMed Central

    Allo, Bedilu A.; Costa, Daniel O.; Dixon, S. Jeffrey; Mequanint, Kibret; Rizkalla, Amin S.

    2012-01-01

    Strategies for bone tissue engineering and regeneration rely on bioactive scaffolds to mimic the natural extracellular matrix and act as templates onto which cells attach, multiply, migrate and function. Of particular interest are nanocomposites and organic-inorganic (O/I) hybrid biomaterials based on selective combinations of biodegradable polymers and bioactive inorganic materials. In this paper, we review the current state of bioactive and biodegradable nanocomposite and O/I hybrid biomaterials and their applications in bone regeneration. We focus specifically on nanocomposites based on nano-sized hydroxyapatite (HA) and bioactive glass (BG) fillers in combination with biodegradable polyesters and their hybrid counterparts. Topics include 3D scaffold design, materials that are widely used in bone regeneration, and recent trends in next generation biomaterials. We conclude with a perspective on the future application of nanocomposites and O/I hybrid biomaterials for regeneration of bone. PMID:24955542

  3. Skin flaps and grafts - self-care

    MedlinePLUS

    ... self-care; Full thickness skin graft - self-care; Partial-dermal skin graft - self-care; FTSG - self-care; ... skin infection Surgery for skin cancer Venous ulcers , pressure ulcers , or diabetic ulcers that do not heal ...

  4. Bioactivation of myelotoxic xenobiotics by human neutrophil myeloperoxidase

    SciTech Connect

    Roy, R.R.

    1989-01-01

    Many environmental pollutants and drugs are toxic to the bone marrow. Some of these xenobiotics may initiate toxicity after undergoing bioactivation to free radicals and/or other reactive electrophiles. Peroxidases are a group of enzymes that catalyze the one-electron oxidative bioactivation of a variety of xenobiotics in vitro. Myeloperoxidase (MPO) is a peroxidative enzyme found in very high concentration in the neutrophils of human bone marrow. In this study, human MPO was evaluated to determine its ability to catalyze the in vitro bioactivation of known bone marrow toxicants that contain the aromatic hydroxyl (Ar-OH), aromatic amine (Ar-N-R{sub 2}), or heterocyclic tertiary amine ({double bond}N-R) moieties. The formation of free radical metabolites during the MPO-catalyzed bioactivation of hydroquinone and catechol (benzene metabolites), mitoxantrone and ametantrone (antitumor drugs), and chlorpromazine and promazine (antipsychotic drugs) was demonstrated by EPR spectroscopy. The reactivity of the products formed during the MPO catalyzed bioactivation of ({sup 14}C)hydroquinone and ({sup 14}C)catechol was shown by their covalent binding to protein and DNA in vitro. The covalently binding metabolite in each case is postulated to be the quinone form of the xenobiotic. In addition, both GSH and NADH were oxidized by the reactive intermediate(s) formed during the MPO-catalyzed bioactivation of many of the bone marrow toxicants tested. It was also shown that p,p-biphenol stimulated the MPO catalyzed bioactivation of both hydroquinone and catechol, while p-cresol stimulated the MPO-catalyzed bioactivation of catechol.

  5. Skin contamination dosimeter

    DOEpatents

    Hamby, David M. (Corvallis, OR); Farsoni, Abdollah T. (Corvallis, OR); Cazalas, Edward (Corvallis, OR)

    2011-06-21

    A technique and device provides absolute skin dosimetry in real time at multiple tissue depths simultaneously. The device uses a phoswich detector which has multiple scintillators embedded at different depths within a non-scintillating material. A digital pulse processor connected to the phoswich detector measures a differential distribution (dN/dH) of count rate N as function of pulse height H for signals from each of the multiple scintillators. A digital processor computes in real time from the differential count-rate distribution for each of multiple scintillators an estimate of an ionizing radiation dose delivered to each of multiple depths of skin tissue corresponding to the multiple scintillators embedded at multiple corresponding depths within the non-scintillating material.

  6. Newborn skin care.

    PubMed

    Dyer, Jonathan A

    2013-02-01

    Many organ systems undergo significant and rapid changes during the transition from an intrauterine to an extrauterine environment, especially those which serve as interfaces between the infant and the external environment. Historically the skin care methods employed during and after this period of rapid physiologic change have been derived from individual anecdotal experience or cultural tradition, rather than evidence-based or pathomechanistically derived data. While research in this area has historically been limited, it is increasing in scope and volume, and recent work has shed light on the changes experienced by the cutaneous organ during this period of transition. This increased understanding has driven new recommendations in skin care protocols for newborn infants and neonates. PMID:23419756

  7. Skin barrier in rosacea*

    PubMed Central

    Addor, Flavia Alvim Sant'Anna

    2016-01-01

    Recent studies about the cutaneous barrier demonstrated consistent evidence that the stratum corneum is a metabolically active structure and also has adaptive functions, may play a regulatory role in the inflammatory response with activation of keratinocytes, angiogenesis and fibroplasia, whose intensity depends primarily on the intensity the stimulus. There are few studies investigating the abnormalities of the skin barrier in rosacea, but the existing data already show that there are changes resulting from inflammation, which can generate a vicious circle caused a prolongation of flare-ups and worsening of symptoms. This article aims to gather the most relevant literature data about the characteristics and effects of the state of the skin barrier in rosacea.

  8. Flies With Skin Blisters.

    PubMed

    Simons, Matias

    2015-08-01

    Epidermolysis bullosa simplex (EBS) belongs to a family of genetic conditions that cause the skin to be fragile and to blister easily. Although most of the genes involved are known, the molecular mechanisms underlying keratin aggregation remain obscure. In this issue of the Journal, Bohnekamp et al. report on a novel EBS model that is based on the de novo formation of keratin filaments in "keratin null flies." PMID:26174537

  9. Nonmelanoma skin cancer.

    PubMed

    Lee, David A; Miller, Stanley J

    2009-08-01

    This article provides readers with a comprehensive review of the evaluation and management of nonmelanoma skin cancers. Treatment recommendations are heavily based on the most recent guidelines from the National Comprehensive Cancer Network. Merkel cell carcinoma and dermatofibrosarcoma protuberans are also discussed. After reviewing this article, readers should be equipped with a better understanding of these entities and the current recommendations for their management. PMID:19698913

  10. Nonmelanoma Skin Cancer

    PubMed Central

    Samarasinghe, Venura; Madan, Vishal

    2012-01-01

    Nonmelanoma skin cancer (NMSC) represents the most common form of cancer in Caucasians, with continuing increase in incidence worldwide. Basal cell carcinoma (BCC) accounts for 75% of cases of NMSC, and squamous cell carcinoma (SCC) accounts for the remaining majority of NMSC cases. Whilst metastasis from BCC is extremely rare, metastasis from high-risk SCC may be fatal. In this article, we review the aetiology, diagnosis and management of NMSC. PMID:22557848

  11. Hollow chitosan/alginate nanocapsules for bioactive compound delivery.

    PubMed

    Rivera, Melissa C; Pinheiro, Ana C; Bourbon, Ana I; Cerqueira, Miguel A; Vicente, Antnio A

    2015-08-01

    This work aimed at the development of biodegradable nanocapsules as carriers of two bioactive compounds, 5-aminosalycilic acid and glycomacropeptide. Nanocapsules were produced through layer-by-layer (LbL) deposition of chitosan (CH) and alginate (ALG) layers on polystyrene nanoparticles. The bioactive compounds were incorporated on the third layer of the nanocapsules being its encapsulation efficiency and release behaviour evaluated. The LbL deposition process, stability, morphology and size of the multilayer nanocapsules were monitored by means of zeta potential and transmission electron microscopy (TEM). The bioactive compounds release from the CH/ALG nanocapsules was successfully described by a mathematical model (linear superimposition model - LSM), which allowed concluding that bioactive compounds release is due to both Brownian motion and the polymer relaxation of the CH/ALG layers. Final results demonstrated that the synthesized LbL hollow nanocapsules presented spherical morphology and a good capacity to encapsulate different bioactive compounds, being the best results obtained for the system containing 5-aminosalycilic acid (with an encapsulation efficiency of approximately 70%). CH/ALG multilayer nanocapsules could be a promising carrier of bioactive compounds for applications in food and pharmaceutical industries. PMID:25907011

  12. Bioactivity of Mg-ion-implanted zirconia and titanium

    NASA Astrophysics Data System (ADS)

    Liang, H.; Wan, Y. Z.; He, F.; Huang, Y.; Xu, J. D.; Li, J. M.; Wang, Y. L.; Zhao, Z. G.

    2007-01-01

    Titanium and zirconia are bioinert materials lacking bioactivity. In this work, surface modification of the two typical biomaterials is conducted by Mg-ion-implantation using a MEVVA ion source in an attempt to increase their bioactivity. Mg ions were implanted into zirconia and titanium with fluences ranging from 1 10 17 to 3 10 17 ions/cm 2 at 40 keV. The Mg-implanted samples, as well as control (unimplanted) samples, were immersed in SBF for 7 days and then removed to identify the presence of calcium and phosphate (Ca-P) coatings and to characterize their morphology and structure by SEM, XRD, and FT-IR. SEM observations confirm that globular aggregates are formed on the surfaces of the Mg-implanted zirconia and titanium while no precipitates are observed on the control samples. XRD and FT-IR analyses reveal that the deposits are carbonated hydroxyapatite (HAp). Our experimental results demonstrate that Mg-implantation improves the bioactivity of zirconia and titanium. Further, it is found that the degree of bioactivity is adjustable by the ion dose. Mechanisms are proposed to interpret the improvement of bioactivity as a result of Mg implantation and the difference in bioactivity between zirconia and titanium.

  13. A Versatile Microarray Platform for Capturing Rare Cells

    NASA Astrophysics Data System (ADS)

    Brinkmann, Falko; Hirtz, Michael; Haller, Anna; Gorges, Tobias M.; Vellekoop, Michael J.; Riethdorf, Sabine; Müller, Volkmar; Pantel, Klaus; Fuchs, Harald

    2015-10-01

    Analyses of rare events occurring at extremely low frequencies in body fluids are still challenging. We established a versatile microarray-based platform able to capture single target cells from large background populations. As use case we chose the challenging application of detecting circulating tumor cells (CTCs) – about one cell in a billion normal blood cells. After incubation with an antibody cocktail, targeted cells are extracted on a microarray in a microfluidic chip. The accessibility of our platform allows for subsequent recovery of targets for further analysis. The microarray facilitates exclusion of false positive capture events by co-localization allowing for detection without fluorescent labelling. Analyzing blood samples from cancer patients with our platform reached and partly outreached gold standard performance, demonstrating feasibility for clinical application. Clinical researchers free choice of antibody cocktail without need for altered chip manufacturing or incubation protocol, allows virtual arbitrary targeting of capture species and therefore wide spread applications in biomedical sciences.

  14. A versatile photoelectron spectrometer for pressures up to 30 mbar

    NASA Astrophysics Data System (ADS)

    Eriksson, Susanna K.; Hahlin, Maria; Kahk, Juhan Matthias; Villar-Garcia, Ignacio J.; Webb, Matthew J.; Grennberg, Helena; Yakimova, Rositza; Rensmo, Hâkan; Edström, Kristina; Hagfeldt, Anders; Siegbahn, Hans; Edwards, Mârten O. M.; Karlsson, Patrik G.; Backlund, Klas; Åhlund, John; Payne, David J.

    2014-07-01

    High-pressure photoelectron spectroscopy is a rapidly developing technique with applications in a wide range of fields ranging from fundamental surface science and catalysis to energy materials, environmental science, and biology. At present the majority of the high-pressure photoelectron spectrometers are situated at synchrotron end stations, but recently a small number of laboratory-based setups have also emerged. In this paper we discuss the design and performance of a new laboratory based high pressure photoelectron spectrometer equipped with an Al Kα X-ray anode and a hemispherical electron energy analyzer combined with a differentially pumped electrostatic lens. The instrument is demonstrated to be capable of measuring core level spectra at pressures up to 30 mbar. Moreover, valence band spectra of a silver sample as well as a carbon-coated surface (graphene) recorded under a 2 mbar nitrogen atmosphere are presented, demonstrating the versatility of this laboratory-based spectrometer.

  15. The PTB microbeam: a versatile instrument for radiobiological research.

    PubMed

    Greif, K; Beverung, W; Langner, F; Frankenberg, D; Gellhaus, A; Banaz-Yasar, F

    2006-01-01

    The PTB microbeam is routinely used for the irradiation of living cells using protons (1-20 MeV) and alpha particles (1-28 MeV). The beam diameter is approximately 2 microm (fwhm), achieved by focussing, resulting in an excellent energy resolution and practically no scattered particles. Recently, an electrostatic beam scanner was added to the facility which allows targeting of each cell within 1 ms. This and other improvements led to an increase in the experimental speed of the system to a maximum of 50,000 cells per hour including all experimental steps. To improve the versatility of the facility further, a module for automatic quantification of immunocytochemical staining was implemented. This allows the analysis of protein activation, taking into account the positional information of the irradiation run. PMID:17164277

  16. Versatile Miniature Tunable Liquid Lenses Using Transparent Graphene Electrodes.

    PubMed

    Shahini, Ali; Xia, Jinjun; Zhou, Zhixian; Zhao, Yang; Cheng, Mark Ming-Cheng

    2016-02-16

    This paper presents, for the first time, versatile and low-cost miniature liquid lenses with graphene as electrodes. Tunable focal length is achieved by changing the droplet curvature using electrowetting on dielectric (EWOD). Ionic liquid and KCl solution are utilized as lens liquid on the top of a flexible Teflon-coated PDMS/parylene membrane. Transparent and flexible, graphene allows transmission of visible light as well as large deformation of the polymer membrane to achieve requirements for different lens designs and to increase the field of view without damaging of electrodes. The tunable range for the focal length is between 3 and 7 mm for a droplet with a volume of 3 ?L. The visualization of bone marrow dendritic cells is demonstrated by the liquid lens system with a high resolution (456 lp/mm). PMID:26800762

  17. VERSATILE TWO-AXIS OPEN-LOOP SOLAR TRACKER CONTROLLER*

    SciTech Connect

    Ward, Christina D; Maxey, L Curt; Evans III, Boyd Mccutchen; Lapsa, Melissa Voss

    2008-01-01

    A versatile single-board controller for two-axis solar tracking applications has been developed and tested on operating solar tracking systems with over two years of field experience. The operating experience gained from the two systems and associated modifications are discussed as representative examples of the practical issues associated with implementing a new two-axis solar tracker design. In this research, open and closed loop control methods were evaluated; however, only the open loop method met the 0.125 tracking accuracy requirement and the requirement to maintain pointing accuracy in hazy and scattered cloudy skies. The open loop algorithm was finally implemented in a microcontroller-based tracking system. Methods of applying this controller hardware to different tracker geometries and hardware are discussed along with the experience gained to date.

  18. Graphene-based nanomaterials for versatile imaging studies.

    PubMed

    Yoo, Je Min; Kang, Jin Hyoun; Hong, Byung Hee

    2015-07-21

    Over the last decade, interest in graphene has surged because of its unprecedented physical, chemical, electrical, and mechanical properties. In recent years, researchers' interests have gradually shifted to other notable properties of graphene - its environmentally-friendly nature with outstanding optical properties. Thus, graphene is considered to be a promising and attractive candidate for various biomedical applications such as NIR-responsive cancer therapy and fluorescence bio-imaging. To that end, appropriate preparation and novel approaches to utilize graphene-based materials such as graphene oxides (GOs), reduced graphene oxides (rGOs), and graphene quantum dots (GQDs) in biology and medical science are gaining growing interest. In this review, we highlight recent applications of graphene-based materials as novel prospects for versatile imaging studies with a brief perspective on their future applications. PMID:25777530

  19. Versatile magnetometer assembly for characterizing magnetic properties of nanoparticles

    NASA Astrophysics Data System (ADS)

    Araujo, J. F. D. F.; Bruno, A. C.; Louro, S. R. W.

    2015-10-01

    We constructed a versatile magnetometer assembly for characterizing iron oxide nanoparticles. The magnetometer can be operated at room temperature or inside a cryocooler at temperatures as low as 6 K. The magnetometer's sensor can be easily exchanged and different detection electronics can be used. We tested the assembly with a non-cryogenic commercial Hall sensor and a benchtop multimeter in a four-wire resistance measurement scheme. A magnetic moment sensitivity of 8.5 × 10-8 Am2 was obtained with this configuration. To illustrate the capability of the assembly, we synthesized iron oxide nanoparticles coated with different amounts of a triblock copolymer, Pluronic F-127, and characterized their magnetic properties. We determined that the polymer coating does not affect the magnetization of the particles at room temperature and demonstrates that it is possible to estimate the average size of coating layers from measurements of the magnetic field of the sample.

  20. Development of a versatile laser light scattering instrument

    NASA Technical Reports Server (NTRS)

    Meyer, William V.; Ansari, Rafat R.

    1990-01-01

    A versatile laser light scattering (LLS) instrument is developed for use in microgravity to measure microscopic particles of 30 A to above 3 microns. Since it is an optical technique, LLS does not affect the sample being studied. A LLS instrument built from modules allows several configurations, each optimized for a particular experiment. The multiangle LLS instrument can be mounted in the rack in the Space Shuttle and on Space Station Freedom. It is possible that a Space Shuttle glove-box and a lap-top computer containing a correlator card can be used to perform a number of experiments and to demonstrate the technology needed for more elaborate investigations. This offers simple means of flying a great number of experiments without the additional requirements of full-scale flight hardware experiments.

  1. The versatility and adaptation of bacteria from the genus Stenotrophomonas

    SciTech Connect

    Ryan, R.P.; van der Lelie, D.; Monchy, S.; Cardinale, M.; Taghavi, S.; Crossman, L.; Avison, M. B.; Berg, G.; Dow, J. M.

    2009-07-01

    The genus Stenotrophomonas comprises at least eight species. These bacteria are found throughout the environment, particularly in close association with plants. Strains of the most predominant species, Stenotrophomonas maltophilia, have an extraordinary range of activities that include beneficial effects for plant growth and health, the breakdown of natural and man-made pollutants that are central to bioremediation and phytoremediation strategies and the production of biomolecules of economic value, as well as detrimental effects, such as multidrug resistance, in human pathogenic strains. Here, we discuss the versatility of the bacteria in the genus Stenotrophomonas and the insight that comparative genomic analysis of clinical and endophytic isolates of S. maltophilia has brought to our understanding of the adaptation of this genus to various niches.

  2. Versatile ferrofluids based on polyethylene glycol coated iron oxide nanoparticles

    NASA Astrophysics Data System (ADS)

    Brullot, W.; Reddy, N. K.; Wouters, J.; Valev, V. K.; Goderis, B.; Vermant, J.; Verbiest, T.

    2012-06-01

    Versatile ferrofluids based on polyethylene glycol coated iron oxide nanoparticles were obtained by a facile protocol and thoroughly characterized. Superparamagnetic iron oxide nanoparticles synthesized using a modified forced hydrolysis method were functionalized with polyethylene glycol silane (PEG silane), precipitated and dried. These functionalized particles are dispersable in a range of solvents and concentrations depending on the desired properties. Examples of tunable properties are magnetic behavior, optical and magneto-optical response, thermal features and rheological behavior. As such, PEG silane functionalized particles represent a platform for the development of new materials that have broad applicability in e.g. biomedical, industrial or photonic environments. Magnetic, optical, magneto-optical, thermal and rheological properties of several ferrofluids based on PEG coated particles with different concentrations of particles dispersed in low molecular mass polyethylene glycol were investigated, establishing the applicability of such materials.

  3. FLUTE: a versatile linac-based THz source.

    PubMed

    Nasse, M J; Schuh, M; Naknaimueang, S; Schwarz, M; Plech, A; Mathis, Y-L; Rossmanith, R; Wesolowski, P; Huttel, E; Schmelling, M; Müller, A-S

    2013-02-01

    A new compact versatile linear accelerator named FLUTE is currently being designed at the Karlsruhe Institute of Technology. This paper presents the status of this 42 MeV machine. It will be used to generate strong (several 100 MV/m) ultra-short (~1 ps) THz pulses (up to ~4-25 THz) for photon science experiments, as well as to conduct a variety of accelerator studies. The latter range from comparing different coherent THz radiation generation schemes to compressing electron bunches and studying the electron beam stability. The bunch charge will cover a wide range (~100 pC-3 nC). Later we plan to also produce ultra-short x-ray pulses from the electron bunches, which, for example, could then be combined for THz pump-x-ray probe experiments. PMID:23464187

  4. A small low-power networked and versatile sensor interface

    NASA Astrophysics Data System (ADS)

    Vincent, Peter S.; McMahon, Phillip J.; Muscat, Richard F.; Zeve, Ladislav; Wilson, Alan R.

    2007-01-01

    Defence Science and Technology Organisation (DSTO) has developed a low power RS485 sensor network that can be hardware configured at design time from a number of modules, depending on its final application. The core predesigned module includes network communications, microprocessor control and digital input/output. A number of analogue sensor interface modules can easily be added to this core. In addition, the software is also of modular design consisting of a set of core operating routines and a set of routines for controlling sensor operations that can be downloaded or upgraded in the field. Prime consideration in this development has been given to the need for small size, low weight, low power and versatility of operation. The hardware is based around the Texas Instruments MSP430 micro-controller. This paper will present some of the considerations leading to the design and examples of applications of the sensor network.

  5. The versatility of spandex photographic retractor for transoral surgical procedures

    PubMed Central

    Tauro, David P.; Uppada, Uday Kiran

    2016-01-01

    The trend toward transoral access, be it for pathology or facial cosmetic surgery, has become increasingly popular over the last two decades with facial incisions being used more and more sporadically than otherwise. Transoral access because of its inherent limitations, retraction of the oral and perioral tissues without inducing physical or thermal injury makes it a daunting task for the operating surgeon. The use of conventional retractors in conjunction with surgical instruments can lead to inadvertent injury to the perioral tissues resulting in untoward postoperative sequelae leading to patient discomfort and delayed recovery. This article elucidates the versatility of a simple photographic retractor (spandex) as a useful adjunctive tool in the retraction and protection of the perioral tissues for almost all transoral surgical procedures. PMID:26937374

  6. Cubosomes and hexosomes as versatile platforms for drug delivery.

    PubMed

    Azmi, Intan Dm; Moghimi, Seyed M; Yaghmur, Anan

    2015-12-01

    Nonlamellar liquid crystalline phases are attractive platforms for drug solubilization and targeted delivery. The attractiveness of this formulation principle is linked to the nanostructural versatility, compatiblity, digestiblity and bioadhesive properties of their lipid constituents, and the capability of solubilizing and sustaining the release of amphiphilic, hydrophobic and hydrophilic drugs. Nonlamellar liquid crystalline phases offer two distinct promising strategies in the development of drug delivery systems. These comprise formation of ISAsomes (internally self-assembled 'somes' or particles) such as cubosomes and hexosomes, and in situ formation of parenteral dosage forms with tunable nanostructures at the site of administration. This review outlines the unique features of cubosomes and hexosomes and their potential utilization as promising platforms for drug delivery. PMID:26652281

  7. Neuronal Chemokines: Versatile Messengers In Central Nervous System Cell Interaction

    PubMed Central

    de Haas, A. H.; van Weering, H. R. J.; de Jong, E. K.; Boddeke, H. W. G. M.

    2007-01-01

    Whereas chemokines are well known for their ability to induce cell migration, only recently it became evident that chemokines also control a variety of other cell functions and are versatile messengers in the interaction between a diversity of cell types. In the central nervous system (CNS), chemokines are generally found under both physiological and pathological conditions. Whereas many reports describe chemokine expression in astrocytes and microglia and their role in the migration of leukocytes into the CNS, only few studies describe chemokine expression in neurons. Nevertheless, the expression of neuronal chemokines and the corresponding chemokine receptors in CNS cells under physiological and pathological conditions indicates that neuronal chemokines contribute to CNS cell interaction. In this study, we review recent studies describing neuronal chemokine expression and discuss potential roles of neuronal chemokines in neuronastrocyte, neuronmicroglia, and neuronneuron interaction. PMID:17952658

  8. Development of versatile molecular transport model for modeling spacecraft contamination

    NASA Astrophysics Data System (ADS)

    Chang, Chien W.; Kannenberg, Keith; Chidester, Michael H.

    2010-08-01

    This paper describes a MATLAB-based molecular transport model developed for modeling contamination of spacecraft and optical instruments in space. The model adopts the Gebhart inverse-matrix theory for thermal radiation to analyze mass (molecular) transfer due to direct and reflected flux processes by balancing the mass fluxes instead of heat fluxes among surfaces with prescribed boundary conditions (contamination sticking fractions). The model can easily input view factor results from current thermal tools as well as measured outgassing data from ASTM E 1559 tests or vacuum bake-outs of flight components. Application examples of a geosynchronous satellite and an optical telescope are given to demonstrate versatile applications of the developed model.

  9. A versatile platform for magnetostriction measurements in thin films

    NASA Astrophysics Data System (ADS)

    Pernpeintner, M.; Holländer, R. B.; Seitner, M. J.; Weig, E. M.; Gross, R.; Goennenwein, S. T. B.; Huebl, H.

    2016-03-01

    We present a versatile nanomechanical sensing platform for the investigation of magnetostriction in thin films. It is based on a doubly clamped silicon nitride nanobeam resonator covered with a thin magnetostrictive film. Changing the magnetization direction within the film plane by an applied magnetic field generates a magnetoelastic stress and thus changes the resonance frequency of the nanobeam. A measurement of the resulting resonance frequency shift, e.g., by optical interferometry, allows to quantitatively determine the magnetostriction constants of the thin film. In a proof-of-principle experiment, we determine the magnetostriction constants of a 10 nm thick polycrystalline cobalt film, showing very good agreement with literature values. The presented technique aims, in particular, for the precise measurement of magnetostriction in a variety of (conducting and insulating) thin films, which can be deposited by, e.g., electron beam deposition, thermal evaporation, or sputtering.

  10. A Versatile Microarray Platform for Capturing Rare Cells.

    PubMed

    Brinkmann, Falko; Hirtz, Michael; Haller, Anna; Gorges, Tobias M; Vellekoop, Michael J; Riethdorf, Sabine; Mller, Volkmar; Pantel, Klaus; Fuchs, Harald

    2015-01-01

    Analyses of rare events occurring at extremely low frequencies in body fluids are still challenging. We established a versatile microarray-based platform able to capture single target cells from large background populations. As use case we chose the challenging application of detecting circulating tumor cells (CTCs)--about one cell in a billion normal blood cells. After incubation with an antibody cocktail, targeted cells are extracted on a microarray in a microfluidic chip. The accessibility of our platform allows for subsequent recovery of targets for further analysis. The microarray facilitates exclusion of false positive capture events by co-localization allowing for detection without fluorescent labelling. Analyzing blood samples from cancer patients with our platform reached and partly outreached gold standard performance, demonstrating feasibility for clinical application. Clinical researchers free choice of antibody cocktail without need for altered chip manufacturing or incubation protocol, allows virtual arbitrary targeting of capture species and therefore wide spread applications in biomedical sciences. PMID:26493176

  11. A versatile technology for droplet-based microfluidics: thermomechanical actuation.

    PubMed

    Miralles, Vincent; Huerre, Axel; Williams, Hannah; Fourni, Bastien; Jullien, Marie-Caroline

    2015-05-01

    We report on a versatile technique for microfluidic droplet manipulation that proves effective at every step: from droplet generation to propulsion to sorting, rearrangement or break-up. Non-wetting droplets are thermomechanically actuated in a microfluidic chip using local heating resistors. Controlled temperature variation induces local dilation of the PDMS wall above the resistor, which drives the droplet away from the hot (i.e. constricted) region (B. Selva, I. Cantat and M.-C. Jullien, Phys. Fluids, 2011, 23, 052002). Adapted placing and actuation of such resistors thus allow us to push forward, stop, store and release, or even break up droplets, at the price of low electric power consumption (<150 mW). We believe this technically accessible method to provide a useful tool for droplet microfluidics. PMID:25849442

  12. A versatile spatial resolution enhancement method for data acquisition

    NASA Astrophysics Data System (ADS)

    Cheng, M. H.; Flores De Jesus, K.; Cronin, S. D.; Sierros, K. A.; Bakhoum, E.

    2015-04-01

    While acquiring specific physical properties within a targeted area, spatial resolution of hardware is usually one of the major limitations that affects the precision of data acquisition. Though measured results with higher spatial resolution are always desired, adequate configuration of hardware setups sometimes implies higher cost or longer acquisition time. In this study, a versatile resolution enhancement method is proposed to improve the sampling resolution. An efficient algorithm is used to convert the lower-resolution data into higher-resolution approximation. Three different engineering applications are used to verify the effectiveness of the proposed method. From the arithmetic results, the spatial sampling resolution can be greatly improved without trading-off the operating time.

  13. Metagenome of a Versatile Chemolithoautotroph from Expanding Oceanic Dead Zones

    SciTech Connect

    Walsh, David A.; Zaikova, Elena; Howes, Charles L.; Song, Young; Wright, Jody; Tringe, Susannah G.; Tortell, Philippe D.; Hallam, Steven J.

    2009-07-15

    Oxygen minimum zones (OMZs), also known as oceanic"dead zones", are widespread oceanographic features currently expanding due to global warming and coastal eutrophication. Although inhospitable to metazoan life, OMZs support a thriving but cryptic microbiota whose combined metabolic activity is intimately connected to nutrient and trace gas cycling within the global ocean. Here we report time-resolved metagenomic analyses of a ubiquitous and abundant but uncultivated OMZ microbe (SUP05) closely related to chemoautotrophic gill symbionts of deep-sea clams and mussels. The SUP05 metagenome harbors a versatile repertoire of genes mediating autotrophic carbon assimilation, sulfur-oxidation and nitrate respiration responsive to a wide range of water column redox states. Thus, SUP05 plays integral roles in shaping nutrient and energy flow within oxygen-deficient oceanic waters via carbon sequestration, sulfide detoxification and biological nitrogen loss with important implications for marine productivity and atmospheric greenhouse control.

  14. FLUTE: A versatile linac-based THz source

    SciTech Connect

    Nasse, M. J.; Schuh, M.; Schwarz, M.; Naknaimueang, S.; Mathis, Y.-L.; Rossmanith, R.; Wesolowski, P.; Huttel, E.; Plech, A.; Schmelling, M.; Mueller, A.-S.

    2013-02-15

    A new compact versatile linear accelerator named FLUTE is currently being designed at the Karlsruhe Institute of Technology. This paper presents the status of this 42 MeV machine. It will be used to generate strong (several 100 MV/m) ultra-short ({approx}1 ps) THz pulses (up to {approx}4-25 THz) for photon science experiments, as well as to conduct a variety of accelerator studies. The latter range from comparing different coherent THz radiation generation schemes to compressing electron bunches and studying the electron beam stability. The bunch charge will cover a wide range ({approx}100 pC-3 nC). Later we plan to also produce ultra-short x-ray pulses from the electron bunches, which, for example, could then be combined for THz pump-x-ray probe experiments.

  15. Advanced Sorbents as a Versatile Platform for Gas Separation

    SciTech Connect

    Neil Stephenson

    2003-09-30

    The program objective was to develop materials and processes for industrial gas separations to reduce energy use and enable waste reduction. The approach chosen combined novel oxygen selective adsorbents and pressure swing adsorption (PSA) processes. Preliminary materials development and process simulation results indicated that oxygen selective adsorbents could provide a versatile platform for industrial gas separations. If fully successful, this new technology offered the potential for reducing the cost of producing nitrogen/oxygen co-products, high purity nitrogen, argon, and possibly oxygen. The potential energy savings for the gas separations are appreciable, but the end users are the main beneficiaries. Lowering the cost of industrial gases expands their use in applications that can employ them for reducing energy consumption and emissions.

  16. Versatile robotic probe calibration for position tracking in ultrasound imaging

    NASA Astrophysics Data System (ADS)

    Eirik Bø, Lars; Fagertun Hofstad, Erlend; Lindseth, Frank; Hernes, Toril A. N.

    2015-05-01

    Within the field of ultrasound-guided procedures, there are a number of methods for ultrasound probe calibration. While these methods are usually developed for a specific probe, they are in principle easily adapted to other probes. In practice, however, the adaptation often proves tedious and this is impractical in a research setting, where new probes are tested regularly. Therefore, we developed a method which can be applied to a large variety of probes without adaptation. The method used a robot arm to move a plastic sphere submerged in water through the ultrasound image plane, providing a slow and precise movement. The sphere was then segmented from the recorded ultrasound images using a MATLAB programme and the calibration matrix was computed based on this segmentation in combination with tracking information. The method was tested on three very different probes demonstrating both great versatility and high accuracy.

  17. AOTF microscope for imaging with increased speed and spectral versatility.

    PubMed Central

    Wachman, E S; Niu, W; Farkas, D L

    1997-01-01

    We have developed a new fluorescence microscope that addresses the spectral and speed limitations of current light microscopy instrumentation. In the present device, interference and neutral density filters normally used for fluorescence excitation and detection are replaced by acousto-optic tunable filters (AOTFs). Improvements are described, including the use of a dispersing prism in conjunction with the imaging AOTF and an oblique-illumination excitation scheme, which together enable the AOTF microscope to produce images comparable to those obtained with conventional fluorescence instruments. The superior speed and spectral versatility of the AOTF microscope are demonstrated by a ratio image pair acquired in 3.5 ms and a micro-spectral absorbance measurement of hemoglobin through a cranial window in a living mouse. Images FIGURE 1 FIGURE 2 FIGURE 4 FIGURE 5 FIGURE 6 FIGURE 7 PMID:9284289

  18. Grinder: a versatile amplicon and shotgun sequence simulator

    PubMed Central

    Angly, Florent E.; Willner, Dana; Rohwer, Forest; Hugenholtz, Philip; Tyson, Gene W.

    2012-01-01

    We introduce Grinder (http://sourceforge.net/projects/biogrinder/), an open-source bioinformatic tool to simulate amplicon and shotgun (genomic, metagenomic, transcriptomic and metatranscriptomic) datasets from reference sequences. This is the first tool to simulate amplicon datasets (e.g. 16S rRNA) widely used by microbial ecologists. Grinder can create sequence libraries with a specific community structure, ? and ? diversities and experimental biases (e.g. chimeras, gene copy number variation) for commonly used sequencing platforms. This versatility allows the creation of simple to complex read datasets necessary for hypothesis testing when developing bioinformatic software, benchmarking existing tools or designing sequence-based experiments. Grinder is particularly useful for simulating clinical or environmental microbial communities and complements the use of in vitro mock communities. PMID:22434876

  19. FLUTE: A versatile linac-based THz source

    NASA Astrophysics Data System (ADS)

    Nasse, M. J.; Schuh, M.; Naknaimueang, S.; Schwarz, M.; Plech, A.; Mathis, Y.-L.; Rossmanith, R.; Wesolowski, P.; Huttel, E.; Schmelling, M.; Mller, A.-S.

    2013-02-01

    A new compact versatile linear accelerator named FLUTE is currently being designed at the Karlsruhe Institute of Technology. This paper presents the status of this 42 MeV machine. It will be used to generate strong (several 100 MV/m) ultra-short (1 ps) THz pulses (up to 4-25 THz) for photon science experiments, as well as to conduct a variety of accelerator studies. The latter range from comparing different coherent THz radiation generation schemes to compressing electron bunches and studying the electron beam stability. The bunch charge will cover a wide range (100 pC-3 nC). Later we plan to also produce ultra-short x-ray pulses from the electron bunches, which, for example, could then be combined for THz pump-x-ray probe experiments.

  20. Preparation of a Versatile Bifunctional Zeolite for Targeted Imaging Applications

    PubMed Central

    Ndiege, Nicholas; Raidoo, Renugan; Schultz, Michael K.; Larsen, Sarah

    2011-01-01

    Bifunctional zeolite Y was prepared for use in targeted in vivo molecular imaging applications. The strategy involved functionalization of the external surface of zeolite Y with chloropropyltriethoxysilane followed by reaction with sodium azide to form azide-functionalized NaY, which is amenable to copper(1) catalyzed click chemistry. In this study, a model alkyne (4-pentyn-1-ol) was attached to the azide-terminated surface via click chemistry to demonstrate feasibility for attachment of molecular targeting vectors (e.g., peptides, aptamers) to the zeolite surface. The modified particle efficiently incorporates the imaging radioisotope gallium-68 (68Ga) into the pores of the azide-functionalized NaY zeolite to form a stable bifunctional molecular targeting vector. The result is a versatile clickable zeolite platform that can be tailored for future in vivo molecular targeting and imaging modalities. PMID:21306141

  1. A versatile nano display platform from bacterial spore coat proteins

    PubMed Central

    Wu, I-Lin; Narayan, Kedar; Castaing, Jean-Philippe; Tian, Fang; Subramaniam, Sriram; Ramamurthi, Kumaran S.

    2015-01-01

    Dormant bacterial spores are encased in a thick protein shell, the coat', which contains ?70 different proteins. The coat protects the spore from environmental insults, and is among the most durable static structures in biology. Owing to extensive cross-linking among coat proteins, this structure has been recalcitrant to detailed biochemical analysis, so molecular details of how it assembles are largely unknown. Here, we reconstitute the basement layer of the coat atop spherical membranes supported by silica beads to create artificial spore-like particles. We report that these synthetic spore husk-encased lipid bilayers (SSHELs) assemble and polymerize into a static structure, mimicking in vivo basement layer assembly during sporulation in Bacillus subtilis. In addition, we demonstrate that SSHELs may be easily covalently modified with small molecules and proteins. We propose that SSHELs may be versatile display platforms for drugs and vaccines in clinical settings, or for enzymes that neutralize pollutants for environmental remediation. PMID:25854653

  2. Extraordinary phylogenetic diversity and metabolic versatility in aquifer sediment

    PubMed Central

    Castelle, Cindy J.; Hug, Laura A.; Wrighton, Kelly C.; Thomas, Brian C.; Williams, Kenneth H.; Wu, Dongying; Tringe, Susannah G.; Singer, Steven W.; Eisen, Jonathan A.; Banfield, Jillian F.

    2013-01-01

    Microorganisms in the subsurface represent a substantial but poorly understood component of the Earth’s biosphere. Subsurface environments are complex and difficult to characterize; thus, their microbiota have remained as a ‘dark matter’ of the carbon and other biogeochemical cycles. Here we deeply sequence two sediment-hosted microbial communities from an aquifer adjacent to the Colorado River, CO, USA. No single organism represents more than ~1% of either community. Remarkably, many bacteria and archaea in these communities are novel at the phylum level or belong to phyla lacking a sequenced representative. The dominant organism in deeper sediment, RBG-1, is a member of a new phylum. On the basis of its reconstructed complete genome, RBG-1 is metabolically versatile. Its wide respiration-based repertoire may enable it to respond to the fluctuating redox environment close to the water table. We document extraordinary microbial novelty and the importance of previously unknown lineages in sediment biogeochemical transformations. PMID:23979677

  3. Versatile robotic probe calibration for position tracking in ultrasound imaging.

    PubMed

    B, Lars Eirik; Hofstad, Erlend Fagertun; Lindseth, Frank; Hernes, Toril A N

    2015-05-01

    Within the field of ultrasound-guided procedures, there are a number of methods for ultrasound probe calibration. While these methods are usually developed for a specific probe, they are in principle easily adapted to other probes. In practice, however, the adaptation often proves tedious and this is impractical in a research setting, where new probes are tested regularly. Therefore, we developed a method which can be applied to a large variety of probes without adaptation. The method used a robot arm to move a plastic sphere submerged in water through the ultrasound image plane, providing a slow and precise movement. The sphere was then segmented from the recorded ultrasound images using a MATLAB programme and the calibration matrix was computed based on this segmentation in combination with tracking information. The method was tested on three very different probes demonstrating both great versatility and high accuracy. PMID:25855886

  4. Nano-Hydroxyapatite/Fluoridated and Unfluoridated Bioactive Glass Composites: Structural Analysis and Bioactivity Evaluation

    SciTech Connect

    Batra, Uma; Kapoor, Seema; Sharma, J. D.

    2011-12-12

    Biphasic bioceramic composites containing nano-hydroxyapatite (HAP) and nanosized bioactive glasses have been prepared in the form of pellets and have been examined for the effects of bioglass concentrations and sintering temperature on the structural transformations and bioactivity behavior. Pure stoichiometric nano-HAP was synthesized using sol-gel technique. Two bioglasses synthesized in this work--fluoridated bioglass (Cao-P{sub 2}O{sub 5}-Na{sub 2}O{sub 3}-CaF{sub 2}) and unfluoridated bioglass (Cao-P{sub 2}O{sub 5}-Na{sub 2}O{sub 3}) designated as FBG and UFBG respectively, were added to nano-HAP with concentrations of 5, 10, 12 and 15%. The average particle sizes of synthesized HAP and bioglasses were 23 nm and 35 nm, respectively. The pellets were sintered at four different temperatures i.e. 1000 deg. C, 1150 deg. C, 1250 deg. C and 1350 deg. C. The investigations involved study of structural and bioactivity behavior of green and sintered pellets and their deviations from original materials i.e. HAP, FBG and UFBG, using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The phase composition of the sintered pellets was found to be non-stoichiometric HAP with {alpha}-TCP (tricalcium phosphate) and {beta}-TCP. It was revealed from SEM images that bonding mechanism was mainly solid state sintering for all pellets sintered at 1000 deg. C and 1150 deg. C and also for pellets with lower concentrations of bioglass i.e. 5% and 10% sintered at 1250 deg. C. Partly liquid phase sintering was observed for pellets with higher bioglass concentrations of 12% and 15% sintered at 1250 deg. C and same behaviour was noted for pellets at all concentrations of bioglasses at 1350 deg. C. The sintered density, hardness and compression strength of pellets have been influenced both by the concentration of the bioglasses and sintering temperature. It was observed that the biological HAP layer formation was faster on the green pellets surface than on pure HAP and sintered pellets, showing higher bioactivity in the green pellets.

  5. Nano-Hydroxyapatite/Fluoridated and Unfluoridated Bioactive Glass Composites: Structural Analysis and Bioactivity Evaluation

    NASA Astrophysics Data System (ADS)

    Batra, Uma; Kapoor, Seema; Sharma, J. D.

    2011-12-01

    Biphasic bioceramic composites containing nano-hydroxyapatite (HAP) and nanosized bioactive glasses have been prepared in the form of pellets and have been examined for the effects of bioglass concentrations and sintering temperature on the structural transformations and bioactivity behavior. Pure stoichiometric nano-HAP was synthesized using sol-gel technique. Two bioglasses synthesized in this work—fluoridated bioglass (Cao-P2O5-Na2O3-CaF2) and unfluoridated bioglass (Cao-P2O5-Na2O3) designated as FBG and UFBG respectively, were added to nano-HAP with concentrations of 5, 10, 12 and 15%. The average particle sizes of synthesized HAP and bioglasses were 23 nm and 35 nm, respectively. The pellets were sintered at four different temperatures i.e. 1000 °C, 1150 °C, 1250 °C and 1350 °C. The investigations involved study of structural and bioactivity behavior of green and sintered pellets and their deviations from original materials i.e. HAP, FBG and UFBG, using X-ray diffraction (XRD) and scanning electron microscopy (SEM). The phase composition of the sintered pellets was found to be non-stoichiometric HAP with α-TCP (tricalcium phosphate) and β-TCP. It was revealed from SEM images that bonding mechanism was mainly solid state sintering for all pellets sintered at 1000 °C and 1150 °C and also for pellets with lower concentrations of bioglass i.e. 5% and 10% sintered at 1250 °C. Partly liquid phase sintering was observed for pellets with higher bioglass concentrations of 12% and 15% sintered at 1250 °C and same behaviour was noted for pellets at all concentrations of bioglasses at 1350 °C. The sintered density, hardness and compression strength of pellets have been influenced both by the concentration of the bioglasses and sintering temperature. It was observed that the biological HAP layer formation was faster on the green pellets surface than on pure HAP and sintered pellets, showing higher bioactivity in the green pellets.

  6. A comparative analysis of metal transportomes from metabolically versatile Pseudomonas

    PubMed Central

    Haritha, Adhikarla; Rodrigue, Agnes; Mohan, Pamarthi Maruthi

    2008-01-01

    Background The availability of complete genome sequences of versatile Pseudomonas occupying remarkably diverse ecological niches enabled to gain insights into their adaptative assets. The objective of this study was to analyze the complete genetic repertoires of metal transporters (metal transportomes) from four representative Pseudomonas species and to identify metal transporters with "Genomic Island" associated features. Methods A comparative metal transporter inventory was built for the following four Pseudomonas species: P.putida (Ppu) KT2440, P.aeruginosa (Pae) PA01, P.fluorescens (Pfl) Pf-5 and P.syringae (Psy)pv.tomato DC3000 using TIGR-CMR and Transport DB. Genomic analysis of essential and toxic metal ion transporters was accomplished from the above inventory. Metal transporters with "Genomic Island" associated features were identified using Islandpath analysis. Results Dataset cataloguing has been executed for 262 metal transporters from the four spp. Additional metal ion transporters belonging to NiCoT, Ca P-type ATPase, Cu P-type ATPases, ZIP and MgtC families were identified. In Psy DC3000, 48% of metal transporters showed strong GI features while it was 45% in Ppu KT2440. In Pfl Pf-5 and Pae PA01 only 26% of their metal transporters exhibited GI features. Conclusion Our comparative inventory of 262 metal transporters from four versatile Pseudomonas spp is the complete suite of metal transportomes analysed till date in a prokaryotic genus. This study identified differences in the basic composition of metal transportomes from Pseudomonas occupying diverse ecological niches and also elucidated their novel features. Based on this inventory we analysed the role of horizontal gene transfer in expansion and variability of metal transporter families. PMID:18816395

  7. Versatile chromium-doped zinc selenide infrared laser sources

    NASA Astrophysics Data System (ADS)

    Berry, Patrick A.

    The atmospheric transmission windows of 2-5 and 8-12 mum, coupled with organic and other chemical absorption lines occurring throughout this middle-infrared (mid-IR) wavelength region give rise to a wide variety of medical, scientific, commercial and military applications. Communications, remote sensing, IR countermeasures, laser surgery and non-invasive imaging are just a few of the drivers of high-power solid-state mid-IR laser development. These laser sources must be versatile enough to operate in a variety of temporal modes from continuous wave (CW) all the way to ultrashort pulse while still being widely tunable for wavelength agility. All of this is required at ever increasing power output levels while conforming to size, weight and power consumption limitations under harsh operating environmental conditions. Chromium-doped zinc selenide (Cr2+:ZnSe) lasers operating in the 2-3 mum region are excellent candidates to help fill these vital roles. As a transition-metal doped II-VI chalcogenide, Cr2+:ZnSe has a number of positive advantages over existing laser sources. Development and power scaling of these lasers however, has been hampered by thermal issues which have so far limited the ability of these lasers to be applied to systems-level development. This work presents research into the nature and mitigation of these critical thermal issues in development of versatile Cr2+:ZnSe laser sources. Advanced models for thermal and laser performance are developed and used to design optimally configured laser systems. Among other advances for this material, >10 W CW output from a Cr2+:ZnSe oscillator and master-oscillator / power amplifier systems producing multi-watt, widely tunable power levels are demonstrated.

  8. Thermal decomposition of bioactive sodium titanate surfaces

    NASA Astrophysics Data System (ADS)

    Ravelingien, Matthieu; Mullens, Steven; Luyten, Jan; Meynen, Vera; Vinck, Evi; Vervaet, Chris; Remon, Jean Paul

    2009-09-01

    Alkali-treated orthopaedic titanium surfaces have earlier shown to induce apatite deposition. A subsequent heat treatment under air improved the adhesion of the sodium titanate layer but decreased the rate of apatite deposition. Furthermore, insufficient attention was paid to the sensitivity of titanium substrates to oxidation and nitriding during heat treatment under air. Therefore, in the present study, alkali-treated titanium samples were heat-treated under air, argon flow or vacuum. The microstructure and composition of their surfaces were characterized to clarify what mechanism is responsible for inhibiting in vitro calcium phosphate deposition after heat treatment. All heat treatments under various atmospheres turned out to be detrimental for apatite deposition. They led to the thermal decomposition of the dense sodium titanate basis near the interface with the titanium substrate. Depending on the atmosphere, several forms of Ti yO z were formed and Na 2O was sublimated. Consequently, less exchangeable sodium ions remained available. This pointed to the importance of the ion exchange capacity of the sodium titanate layer for in vitro bioactivity.

  9. Burchellin: study of bioactivity against Aedes aegypti

    PubMed Central

    2014-01-01

    Background The dengue mosquito Aedes aegypti Linnaeus, 1762 is a widespread insect pest of serious medical importance. Since no effective vaccine is available for treating dengue, the eradication or control of the main mosquito vector is regarded as essential. Since conventional insecticides have limited success, plants may be an alternative source of larvicidal agents, since they contain a rich source of bioactive chemicals. The aim of this study was to evaluate the larvicidal activity of the neolignan burchellin isolated from Ocotea cymbarum (Lauraceae), a plant from the Amazon region, against third instar larvae of A. aegypti. Methods Burchellin obtained from O. cymbarum was analyzed. The inhibitory activity against A. aegypti eggs and larvae and histological changes in the digestive system of treated L3 larvae were evaluated. In addition, nitric oxide synthase activity and nitric oxide levels were determined, and cytotoxicity bioassays performed. Results The data showed that burchellin interfered with the development cycle of the mosquito, where its strongest toxic effect was 100% mortality in larvae (L3) at concentrations???30 ppm. This compound did not show target cell toxicity in peritoneal macrophages from BALB/c mice, and proved to have molecular stability when dissolved in water. The L3 and L4 larvae treated with the compound showed cellular destruction and disorganization, cell spacing, and vacuolization of epithelial cells in small regions of the midgut. Conclusion The neolignan burchellin proved to be a strong candidate for a natural, safe and stable phytolarvicidal to be used in population control of A. aegypti. PMID:24713267

  10. Cocoa flavanols - measurement, bioavailability and bioactivity.

    PubMed

    Kwik-Uribe, Catherine; Bektash, Roger M

    2008-01-01

    There has been growing interest in the potential cardiovascular benefits associated with cocoa consumption. As a result of accurate analytical methodologies, there is evidence to support that the flavanols in cocoa can be absorbed, are bioactive, and may be responsible for the cardiovascular benefits associated with regular cocoa consumption. The flavanols in cocoa exist in a multitude of different stereochemical configurations, thus giving rise to a unique and complex mixture of compounds. Given this complexity, the quantitative analysis of cocoa flavanols in foods can be challenging. While there are published methods suitable for the analysis of these compounds, these methods require sophisticated instrumentation and can be challenging to set up. As such, simpler techniques that measure such things as total phenolic content or antioxidant potential have been used as indicators of flavanol content. However, as these simpler assays are prone to interferences and are not specific for flavanols, these methods are not appropriate for use in studies that aim to examine the physiological effects of cocoa flavanols. It is only through the use of methods that can accurately quantify these flavanols that it will be possible to make meaningful dietary recommendations regarding the consumption of cocoa flavanol containing foods. PMID:18296356

  11. Bioactivities of phytochemicals in Araiostegia yunnanensis (Christ).

    PubMed

    Chen, Longsheng; Xu, Wei; Shao, Rong; Du, Xianfeng

    2015-11-01

    The profile and bioactivity of phytochemicals in Araiostegia yunnanensis (Christ) Cop were investigated. The total flavonoids content in A. yunnanensis is about 84.90 mg/g. By means of HPLC-DAD-ESI-MS, the main flavonoids in A. yunnanensis were tentatively identified as myricetin 3-O-rhamnosylglucoside, eriodictyol 7-O-rutinoside, quercetin 3-O-rutinoside, luteolin-7-O-apiosylglucoside, quercetin 3-O-rhamnosylgalactoside, and luteolin 7-O-glucoside. The extract (0.268 mg/ml total flavonoids) from A. yunnanensis showed very strong superoxide anion radical scavenging potential and reducing power, which are higher than those of rutin (0.25 mg/ml). The extract (0.268 mg/ml total flavonoids) from A. yunnanensis exhibited similar DPPH scavenging activity with rutin (0.25 mg/ml). However, rutin (0.25 mg/ml) showed a significantly higher ABTS radical scavenging effect than that of the extract (0.268 mg/ml total flavonoids) from A. yunnanensis. The methanol extract from A. yunnanensis showed obviously cytotoxic effects on A549 cells and it had no effect against acetylcholinesterase. PMID:25976789

  12. Clinical applications of bioactive milk components.

    PubMed

    Hill, David R; Newburg, David S

    2015-07-01

    Milk represents a unique resource for translational medicine: It contains a rich pool of biologically active molecules with demonstrated clinical benefits. The ongoing characterization of the mechanistic process through which milk components promote development and immunity has revealed numerous milk-derived compounds with potential applications as clinical therapies in infectious and inflammatory disease, cancer, and other conditions. Lactoferrin is an effective antimicrobial and antiviral agent in high-risk patient populations and a potentially potent adjuvant to chemotherapy in lung cancer. Enteric nutrition formulas supplemented with transforming growth factor β, a milk cytokine, have been shown to promote remission in pediatric Crohn's disease. A number of milk glycans, including human milk oligosaccharides, show promise in preclinical studies as antimicrobial and anti-inflammatory agents. While active preclinical investigations of human milk may soon result in large-scale production of human milk molecules, bovine milk components in many instances represent a practical source of bioactive milk compounds for use in clinical trials. This review summarizes current efforts to translate the compounds derived from human and bovine milk into effective clinical therapies. These efforts suggest a common pathway for the translation of milk-derived compounds into clinical applications. PMID:26011900

  13. Cognition, dopamine and bioactive lipids in schizophrenia

    PubMed Central

    Condray, Ruth; Yao, Jeffrey K.

    2011-01-01

    Schizophrenia is a remarkably complex disorder with a multitude of behavioral and biological perturbations. Cognitive deficits are a core feature of this disorder, and involve abnormalities across multiple domains, including memory, attention, and perception. The complexity of this debilitating illness has led to a view that the key to unraveling its pathophysiology lies in deconstructing the clinically-defined syndrome into pathophysiologically distinct intermediate phenotypes. Accumulating evidence suggests that one of these intermediate phenotypes may involve phospholipid signaling abnormalities, particularly in relation to arachidonic acid (AA). Our data show relationships between levels of AA and performance on tests of cognition for schizophrenia patients, with defects in AA signaling associated with deficits in cognition. Moreover, dopamine may moderate these relationships between AA and cognition. Taken together, cognitive deficits, dopaminergic neurotransmission, and bioactive lipids have emerged as related features of schizophrenia. Existing treatment options for cognitive deficits in schizophrenia do not specifically target lipid-derived signaling pathways; understanding these processes could inform efforts to identify novel targets for treatment innovation. PMID:21196378

  14. Screening for bioactive compounds from algae.

    PubMed

    Plaza, M; Santoyo, S; Jaime, L; Garca-Blairsy Reina, G; Herrero, M; Seorns, F J; Ibez, E

    2010-01-20

    In the present work, a comprehensive methodology to carry out the screening for novel natural functional compounds is presented. To do that, a new strategy has been developed including the use of unexplored natural sources (i.e., algae and microalgae) together with environmentally clean extraction techniques and advanced analytical tools. The developed procedure allows also estimating the functional activities of the different extracts obtained and even more important, to correlate these activities with their particular chemical composition. By applying this methodology it has been possible to carry out the screening for bioactive compounds in the algae Himanthalia elongata and the microalgae Synechocystis sp. Both algae produced active extracts in terms of both antioxidant and antimicrobial activity. The obtained pressurized liquid extracts were chemically characterized by GC-MS and HPLC-DAD. Different fatty acids and volatile compounds with antimicrobial activity were identified, such as phytol, fucosterol, neophytadiene or palmitic, palmitoleic and oleic acids. Based on the results obtained, ethanol was selected as the most appropriate solvent to extract this kind of compounds from the natural sources studied. PMID:19375880

  15. Radiation Parameters of Some Potential Bioactive Compounds.

    PubMed

    Gedik, Zeynep; Tugrak, Mehtap; Dastan, Aysenur; Gul, Halise Inci; Yilmaz, Demet

    2015-06-01

    In this study, we aimed to determine the radiation parameters of some potential bioactive compounds. 1-Aryl-3-dibenzylamino-propane-1-on hydrochloride type Mannich bases were synthesized via classical conventional heating method. Aryl part was changed as phenyl (C6H5), 4-methylphenyl (4-CH3C6H4), 4-fluorophenyl ( 4-FC6H4), 4-nitrophenyl (4-NO2C6H4), 4-chlorophenyl (4-ClC6H4), 4-bromophenyl (4-BrC6H4), and 2-thienyl (C4H3S-2-yl). Mass attenuation coefficient (μm), effective atomic number (Z(eff)) and effective electron density (N(el)) of compounds were determined experimentally and theoretically for at 8.040, 8.910, 13.40, 14.96, 17.48, 19.61, 22.16, 24.94, 32.19, 36.38, 44.48, 50.38 and 59.54 keV photon energies by using an HPGe detector with a resolution of 182 eV at 5.9 keV. Radiation parameters of these compounds which can be anti-cancer drug candidate were given in the tables. The results show that phenyl ring behave like thiophene ring in terms of radiation absorption. It is thought that the results of study may drive allow the development of drug candidate new compounds in medical oncology. PMID:26601355

  16. Antioxidant effects of natural bioactive compounds.

    PubMed

    Balsano, Clara; Alisi, Anna

    2009-01-01

    Reactive oxygen species (ROS), as well as reactive nitrogen species (RNS) play either harmful or beneficial role in biological systems. Beneficial effects of ROS include physiological roles in cellular responses against infectious agents and in several cellular signalling pathways. Harmful effects are due to high concentrations of ROS, which can damage biomolecules, including lipids, proteins and nucleic acids. The harmful effects of ROS are counterbalanced by the antioxidant action of both antioxidant enzymes and non-enzymatic antioxidants; however, despite the presence of the cell's antioxidant system, oxidative damage accumulates during the life cycle and has been proposed to play a pivotal role in the development of age-dependent diseases such as atherosclerosis, arthritis, neurodegenerative disorders and cancer. Numerous epidemiological studies indicate that a reduced risk of various lifestyle diseases, mainly cardiovascular diseases and cancer, as well as other disorders, is associated to a diet rich in fruits, vegetables and their products. The drive to enhance the consumption of fruits and vegetables in the human diet is linked with positive effects of beneficial antioxidants impacting on health promotion. In this review we present an outline of main roles of ROS in biological processes and diseases and how natural bioactive compounds of fruits and vegetables determine their health-promoting properties. PMID:19754380

  17. Triterpene composition and bioactivities of Centella asiatica.

    PubMed

    Hashim, Puziah; Sidek, Hamidah; Helan, Mohd Helme M; Sabery, Aidawati; Palanisamy, Uma Devi; Ilham, Mohd

    2011-01-01

    Leaves of Centella asiatica (Centella) were analysed for their triterpene composition and bioactivity such as collagen enhancement, antioxidant, anticellulite and UV protection capacity properties. Triterpenes of Centella were measured using HPLC-PAD on an Excil ODS 5 mm (C18) column for the simultaneous determination of asiatic acid, madecassic acid, asiaticoside and madecassoside. Centella was found to contain significant amounts of madecassoside (3.10 4.58 mg/mL) and asiaticoside (1.97 2.65 mg/mL), but was low in asiatic and madecassic acid. The highest collagen synthesis was found at 50 mg/mL of Centella extracts. The antioxidant activity of Centella (84%) was compared to grape seed extract (83%) and Vitamin C (88%). Its lipolytic activity was observed by the release of glycerol (115.9 mol/L) at 0.02% concentration. Centella extracts exhibited similar UV protection effect to OMC at 10% concentration. In view of these results, the potential application of Centella in food and pharmaceutical industries is now widely open. PMID:21278681

  18. The versatility of perforator-based propeller flap for reconstruction of distal leg and ankle defects.

    PubMed

    Karki, Durga; Narayan, R P

    2012-01-01

    Introduction. Soft tissue coverage of distal leg and ankle region represents a challenge and such defect usually requires a free flap. However, this may lead to considerable donor site morbidity, is time consuming, and needs facility of microsurgery. With the introduction of perforator flap, management of small- and medium-size defects of distal leg and ankle region is convenient, less time consuming, and with minimal donor site morbidity. When local perforator flap is designed as propeller and rotated to 180 degree, donor site is closed primarily and increases reach of flap, thus increasing versatility. Material and Methods. From June 2008 to May 2011, 20 patients were treated with perforator-based propeller flap for distal leg and ankle defects. Flap was based on single perforator of posterior tibial and peroneal artery rotated to 180 degrees. Defect size was from 4 cm × 3.5 cm to 7 cm × 5 cm. Results. One patient developed partial flap necrosis, which was managed with skin grafting. Two patients developed venous congestion, which subsided spontaneously without complications. Small wound dehiscence was present in one patient. Donor site was closed primarily in all patients. Rest of the flaps survived well with good aesthetic results. Conclusion. The perforator-based propeller flap for distal leg and ankle defects is a good option. This flap design is safe and reliable in achieving goals of reconstruction. The technique is convenient, less time consuming, and with minimal donor site morbidity. It provides aesthetically good result. PMID:22567253

  19. Utility of High-Frequency Ultrasound: Moving Beyond the Surface to Detect Changes in Skin Integrity

    PubMed Central

    Lucas, Valentina S.; Burk, Ruth S.; Creehan, Sue; Grap, Mary Jo

    2014-01-01

    Ultrasound imaging is a versatile modality frequently used in clinical medicine, most likely due to its low cost, low risk to patients, and the ability to provide images in real time. Ultrasound used typically in clinical settings has frequencies between 2 and 12 MHz. Lower frequencies produce greater resolution but are limited in depth penetration; higher frequencies produce greater resolution, but depth of penetration is limited. High-frequency ultrasound (HFUS) shows promise for detection of certain changes in the skin and this has implications for early detection of changes associated with pressure ulcer formation and wound healing. The purpose of this article was to provide an overview of where HFUS has been used with the skin and provide some discussion on its utility with detecting skin changes related to pressure. PMID:24583666

  20. Interactions of bioactive glass materials in the oral environment

    NASA Astrophysics Data System (ADS)

    Efflandt, Sarah Elizabeth

    The aim of this research was to investigate bioactive glass materials for their use in dental restorations. Mechanical properties such as strength, toughness and wear resistance were considered initially, but the focus of this thesis was the biological properties such as reactions with saliva and interactions with natural dental tissues. Bioactive composite materials were created by incorporating bioactive glass and alumina powders into an aqueous suspension, slip casting, and infiltrating with resin. Microstructure, mechanical properties and wear resistance were evaluated. Mechanically, the composites are comparable to natural dental tissues and current dental materials with a strength of 206 +/- 18.7 MPa and a toughness of 1.74 +/- 0.08 MPa(m)1/2. Interfacial reactions were examined using bulk bioactive glasses. Disks were prepared from a melt, placed in saliva and incubated at 37°C. Surfaces were analyzed at 2, 5, 10, 21, and 42 days using scanning electron microscopy (SEM) and microdiffraction. Results showed changes at 2 days with apatite crystallization by 10 days. These glass disks were then secured against extracted human dentin and incubated in saliva for 21 or 42 days. Results from SEM, electron microprobe analysis (EMPA) and microdiffraction showed that dentin and bioactive glasses adhered in this in vitro environment due to attraction of collagen to bioactive glasses and growth of an interfacial apatite. After investigating these bulk glass responses, particulate bioactive glasses were placed in in vitro and in vivo set-ups for evaluation. Particles immersed in biologically buffered saliva showed crystallization of apatite at 3 days. These bioactive glass particles were placed in the molars of mini-pigs and left in vivo. After 30 days the bioactive paste was evaluated using SEM, EMPA and microdiffraction analyses. Results showed that the paste gained structural integrity and had chemical changes in vivo. These sets of experiments show that bioactive glasses have many mechanical and biological characteristics desirable for use in dental materials. Hopefully, the conclusions presented here will lead to further investigations toward their use in dentistry.