Sample records for photosensitizer rose bengal

  1. Cationic Phosphorus Dendrimer Enhances Photodynamic Activity of Rose Bengal against Basal Cell Carcinoma Cell Lines.

    PubMed

    Dabrzalska, Monika; Janaszewska, Anna; Zablocka, Maria; Mignani, Serge; Majoral, Jean Pierre; Klajnert-Maculewicz, Barbara

    2017-05-01

    In the last couple of decades, photodynamic therapy emerged as a useful tool in the treatment of basal cell carcinoma. However, it still meets limitations due to unfavorable properties of photosensitizers such as poor solubility or lack of selectivity. Dendrimers, polymers widely studied in biomedical field, may play a role as photosensitizer carriers and improve the efficacy of photodynamic treatment. Here, we describe the evaluation of an electrostatic complex of cationic phosphorus dendrimer and rose bengal in such aspects as singlet oxygen production, cellular uptake, and phototoxicity against three basal cell carcinoma cell lines. Rose bengal-cationic dendrimer complex in molar ratio 5:1 was compared to free rose bengal. Obtained results showed that the singlet oxygen production in aqueous medium was significantly higher for the complex than for free rose bengal. The cellular uptake of the complex was 2-7-fold higher compared to a free photosensitizer. Importantly, rose bengal, rose bengal-dendrimer complex, and dendrimer itself showed no dark toxicity against all three cell lines. Moreover, we observed that phototoxicity of the complex was remarkably enhanced presumably due to high cellular uptake. On the basis of the obtained results, we conclude that rose bengal-cationic dendrimer complex has a potential in photodynamic treatment of basal cell carcinoma.

  2. Phosphorus dendrimers and photodynamic therapy. Spectroscopic studies on two dendrimer-photosensitizer complexes: Cationic phosphorus dendrimer with rose bengal and anionic phosphorus dendrimer with methylene blue.

    PubMed

    Dabrzalska, Monika; Zablocka, Maria; Mignani, Serge; Majoral, Jean Pierre; Klajnert-Maculewicz, Barbara

    2015-08-15

    Dendrimers due to their unique architecture may play an important role in drug delivery systems including chemotherapy, gene therapy and recently, photodynamic therapy as well. We investigated two dendrimer-photosensitizer systems in context of potential use of these systems in photodynamic therapy. The mixtures of an anionic phosphorus dendrimer of the second generation and methylene blue were studied by UV-vis spectroscopy while that of a cationic phosphorus dendrimer (third generation) and rose bengal were investigated by spectrofluorimetric methods. Spectroscopic analysis of these two systems revealed the formation of dendrimer-photosensitizer complexes via electrostatic interactions as well as π stacking. The stoichiometry of the rose bengal-cationic dendrimer complex was estimated to be 7:1 and 9:1 for the methylene blue-anionic dendrimer complex. The results suggest that these polyanionic or polycationic phosphorus dendrimers can be promising candidates as carriers in photodynamic therapy. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Assessment of Rose Bengal vs. Riboflavin Photodynamic Therapy for Inhibition of Fungal Keratitis Isolates

    PubMed Central

    Arboleda, Alejandro; Miller, Darlene; Cabot, Florence; Taneja, Mukesh; Aguilar, Mariela C.; Alawa, Karam; Amescua, Guillermo; Yoo, Sonia H.; Parel, Jean-Marie

    2014-01-01

    Purpose To compare the in vitro effect of rose bengal and riboflavin as photosensitizing agents for photodynamic therapy (PDT) on fungal isolates that are common causes of fungal keratitis Design Experimental study Methods Three isolates (Fusarium solani, Aspergillus fumigatus, Candida albicans) recovered from patients with confirmed fungal keratitis were used in the experiments. Isolates were grown on Sabouraud-Dextrose agar, swabbed and prepared in suspension, and one milliliter aliquots were inoculated onto test plates in triplicate. Test plates were separated into 5 groups: Group 1 - no treatment, Group 2 - 0.1% rose bengal alone, Group 3 - 518 nm irradiation alone, Group 4 - riboflavin PDT (riboflavin + 375 nm irradiation), and Group 5 - rose bengal PDT (rose bengal + 518 nm irradiation). Irradiation was performed over a circular area using either a green LED array (peak wavelength: 518 nm) or a UV-A LED array (peak wavelength: 375 nm). Test plates were irradiated with an energy density of 5.4 J/cm2. Later, plates were placed in a 30° C incubator and observed for growth. Results Rose bengal-mediated PDT successfully inhibited the growth of all three fungal isolates in the irradiated area. All other groups exhibited unrestricted growth throughout the plate. Conclusions Rose bengal-mediated PDT successfully inhibited the growth of three types of fungi. No other experimental groups, including riboflavin-mediated PDT, had any inhibitory effect on the isolates. The results might be useful for the treatment of patients suffering from corneal infection. PMID:24792103

  4. Interaction between rose bengal and different protein components.

    PubMed

    Tseng, S C; Zhang, S H

    1995-07-01

    Bindings of rose bengal to several proteins were determined by Sephadex G-75 chromatography. Their respective blocking effect against dye uptake was demonstrated in an assay using a rabbit corneal epithelial cell layer. The total binding capacity of nonmucin proteins was measured using fluorometry and Scatchard analysis. The results showed that albumin, lactoferrin, transferrin, and lysozyme could--but serum prealbumin, IgA, carboxymethyl cellulose (CMC), and Sepharose 4B-purified porcine stomach mucin (PSM) could not--bind rose bengal. Lysozyme formed precipitates with rose bengal. Sufficient concentrations of albumin, lactoferrin, transferrin, or lysozyme premixed with rose bengal could block dye uptake by cells, but IgA and serum prealbumin could not. Premixed PSM was not as effective as precoated PSM in blocking dye uptake. The dissociation constant (Kd) was 1.2 x 10(-7) M, 3.6 x 10(-7) M, 3.9 x 10(-7) M, and 1.6 x 10(-6) M for albumin, transferrin, lactoferrin, and lysozyme, respectively. Based on these values, the total maximal binding capacity of nonmucin proteins in normal 7-microliters tears was extrapolated to be 0.249 micrograms rose bengal, which is too small to explain the negative staining of rose bengal on the normal ocular surface. Rose bengal, but not fluorescein, could interact with carbohydrate-containing Sephadex, CMC, and PSM to slow down its elution via Sephadex column chromatography. Therefore, the normal negative staining to rose bengal might be caused by the blocking effect of preocular mucus tear layer, which serves as a diffusion barrier. Rose bengal remains a unique dye for detecting the protective function of the preocular mucus tear.

  5. Photosensitized rose Bengal-induced phototoxicity on human melanoma cell line under natural sunlight exposure.

    PubMed

    Srivastav, Ajeet K; Mujtaba, Syed Faiz; Dwivedi, Ashish; Amar, Saroj K; Goyal, Shruti; Verma, Ankit; Kushwaha, Hari N; Chaturvedi, Rajnish K; Ray, Ratan Singh

    2016-03-01

    Rose Bengal (RB) is an anionic water-soluble xanthene dye, which used for many years to assess eye cornea and conjunctiva damage. RB showed strong absorption maxima (λmax) under visible light followed by UV-B and UV-A. RB under sunlight exposure showed a time-dependent photodegradation. Our results show that photosensitized RB generates (1)O2 via Type-II photodynamic pathway and induced DNA damage under sunlight/UV-R exposure. 2'dGuO degradation, micronuclei formation, and single- and double-strand breakage were the outcome of photogenotoxicity caused by RB. Quenching studies with NaN3 advocate the involvement of (1)O2 in RB photogenotoxicity. RB induced linoleic acid photoperoxidation, which was parallel to (1)O2-mediated DNA damage. Oxidative stress in A375 cell line (human melanoma cell line) was detected through DCF-DA assay. Photosensitized RB decreased maximum cellular viability under sunlight followed by UV-B and UV-A exposures. Apoptosis was detected as a pattern of cell death through the increased of caspase-3 activity, decreased mitochondrial membrane potential, and PS translocation through inner to outer plasma membrane. Increased cytosolic levels of Bax also advocate the apoptotic cell death. We propose a p53-mediated apoptosis via increased expression of Bax gene and protein. Thus, the exact mechanism behind RB phototoxicity was the involvement of (1)O2, which induced oxidative stress-mediated DNA and membrane damage, finally apoptotic cell death under natural sunlight exposure. The study suggests that after the use of RB, sunlight exposure may avoid to prevent from its harmful effects. Copyright © 2015. Published by Elsevier B.V.

  6. Rose bengal-grafted biodegradable microcapsules: singlet-oxygen generation and cancer-cell incapacitation.

    PubMed

    Wang, Xiao-Lei; Zeng, Yu; Zheng, Yan-Zhen; Chen, Jian-Feng; Tao, Xia; Wang, Ling-Xuan; Teng, Yan

    2011-09-26

    Rose bengal-grafted chitosan (RB-CHI), synthesized through dehydration between amino and carboxyl functional groups under mild conditions, was coated onto the outer layer of preformed biodegradable microcapsules consisting of sodium alginate and chitosan. The fabricated photosensitive microcapsules were characterized by optical microscopy, scanning electron microscopy, and confocal laser scanning microscopy. The assembled materials maintained intact spherical morphology and thus showed good ability to form thin films. Electron spin resonance spectroscopy allowed direct observation of the generation of singlet oxygen ((1)O(2)) from photosensitive microcapsules under light excitation at about 545 nm. Furthermore, with increasing light radiation, the content of (1)O(2) increased, as detected by a chemical probe. In vitro cellular toxicity assays showed that RB-CHI-coated photosensitive microcapsules exhibit good biocompatibility in darkness and high cytotoxicity after irradiation, and could provide new photoresponsive drug-delivery vehicles. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Effect of dye localization and self-interactions on the photosensitized generation of singlet oxygen by rose bengal bound to bovine serum albumin.

    PubMed

    Turbay, María Beatriz Espeche; Rey, Valentina; Argañaraz, Natalia M; Morán Vieyra, Faustino E; Aspée, Alexis; Lissi, Eduardo A; Borsarelli, Claudio D

    2014-12-01

    The spectroscopic and photophysical properties of rose bengal (RB) encased in bovine serum albumin (BSA) have been examined to evaluate the photosensitized generation of singlet molecular oxygen ((1)O2). The results show that RB photophysical and photosensitizing properties are highly modulated by the average number of dye molecules per protein (n). At n ≪ 1, the dye molecule is tightly located into the hydrophobic nanocavity site I of the BSA molecule with a binding constant Kb = 0.15 ± 0.01 μM(-1). The interaction with surrounding amino acids induces heterogeneous decay of both singlet and triplet excited states of RB and partially reduce its triplet quantum yield as compared with that in buffer solution. However, despite of the diffusive barrier imposed by the protein nanocavity to (3)O2, the quenching of (3)RB(∗):BSA generates (1)O2 with quantum yield ΦΔ = 0.35 ± 0.05. In turns, the intraprotein generated (1)O2 is able to diffuse through the bulk solution, where is dynamically quenched by BSA itself with an overall quenching rate constant of 7.3 × 10(8) M(-1) s(-1). However, at n>1, nonspecific binding of up to ≈ 6RB molecules per BSA is produced, allowing efficient static quenching of excited states of RB preventing photosensitization of (1)O2. These results provide useful information for development of dye-protein adducts suitable for using as potential intracellular photosensitizers. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Topical liposomal Rose Bengal for photodynamic white hair removal: randomized, controlled, double-blind study.

    PubMed

    Samy, Nevien; Fadel, Maha

    2014-04-01

    Blond and white hair removal by laser is a complicated task with weak satisfactory results due to the deficiency in laser-absorbing chromophore. To investigate if repetitive sessions of photodynamic therapy (PDT) using external application of liposomal Rose bengal (RB) photosensitizer followed by intense pulsed light (IPL) exposure enables removal of gray and white hair. Rose bengal loaded in liposomes (LRB) was constructed, prepared in hydrogel, and was studied for some pharmaceutical properties. Penetration and selective hair follicle damage in mice skin were studied. Topical gel containing LRB was used for treating fifteen adult females who were complaining of facial white terminal hair. Unwanted facial hair was treated for three sessions at intervals of 4-6 weeks using intense pulsed light (IPL). At each session, the treatment area was pre-treated with topical LRB gel, while a control group of another 15 patients applied placebo gel before IPL treatment. Evaluations included hair regrowth, which was measured 4 weeks after each treatment session and at 6 months follow-up by counting the number of terminal hair compared with baseline pretreatment values. Treatment outcomes and complications if any were also reported. Average hair regrowth in the LRB group was 56% after 3 treatment cycles. After six-months follow up, average terminal hair count compared with baseline pretreatment showed 40% reduction and no recorded side effects. A significant difference (P<0.05) was seen compared with the control group; the clinical results were promising. Photodynamic hair removal using rose bengal-encapsulated liposomal gel in combination with IPL treatment showed significant efficacy in the treatment of white hair compared with a control group.

  9. Mucin characteristics of human corneal-limbal epithelial cells that exclude the rose bengal anionic dye.

    PubMed

    Argüeso, Pablo; Tisdale, Ann; Spurr-Michaud, Sandra; Sumiyoshi, Mika; Gipson, Ilene K

    2006-01-01

    Rose bengal is an organic anionic dye used to assess damage of the ocular surface epithelium in ocular surface disease. It has been proposed that mucins have a protective role, preventing rose bengal staining of normal ocular surface epithelial cells. The current study was undertaken to evaluate rose bengal staining in a human corneal-limbal epithelial (HCLE) cell line known to produce and glycosylate membrane-associated mucins. HCLE cells were grown to confluence in serum-free medium and switched to DMEM/F12 with 10% serum to promote differentiation. Immunolocalization of the membrane-associated mucins MUC1 and MUC16 and the T-antigen carbohydrate epitope was performed with the monoclonal antibodies HMFG-2 and OC125 and jacalin lectin, respectively. To assess dye uptake, cultures were incubated for 5 minutes with 0.1% rose bengal and photographed. To determine whether exclusion of negatively charged rose bengal requires a negative charge at the cell surface, cells were incubated with fluoresceinated cationized ferritin. The effect of hyperosmotic stress on rose bengal staining in vitro was evaluated by increasing the ion concentration (Ca+2 and Mg+2) in the rose bengal uptake assay. The cytoplasm and nucleus of confluent HCLE cells cultured in media without serum, lacking the expression of MUC16 but not MUC1, as well as human corneal fibroblasts, which do not express mucins, stained with rose bengal. Culture of HCLE cells in medium containing serum resulted in the formation of islands of stratified cells that excluded rose bengal. Apical cells of the stratified islands produced MUC16 and the T-antigen carbohydrate epitope on their apical surfaces. Colocalization experiments demonstrated that fluoresceinated cationized ferritin did not bind to these stratified cells, indicating that rose bengal is excluded from cells that lack negative charges. Increasing the amounts of divalent cations in the media reduced the cellular area protected against rose bengal uptake

  10. Modeling the effect of Rose Bengal on growth and decay patterns of Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus

    NASA Astrophysics Data System (ADS)

    Al-Akhras, M.-Ali H.; Shorman, Mohammad Al; Masadeh, Majed M.; Aljarrah, Khaled; Ababneh, Zaid

    2018-02-01

    Most infections caused by (Pseudomonas aeruginosa, Escherichia coli and Staphylococcus aureus) are hospital and community acquired infections in patients. Bacterial growths incorporated with photosensitizing material (Rose Bengal) with and without light were investigated. The results demonstrated that the viable counts are increasing in absence of light (in dark) for all samples incorporated with Rose Bengal. Variation in growth phases were noticed as expected, but there is no significant change in decay phases. Convenient and adequate mathematical modeling is in very good agreement with the experimental results and showed to be a very good approach of characterization the growth behaviors of the bacteria. Bandwidths are independent of bacteria group (gram-positive or gram-negative) but it seems totally dependent on the oxygen requirements; an anaerobic bacterium takes broader bandwidths than aerobic bacteria. This concludes that the growth and lethal rates of anaerobic are much greater than aerobic.

  11. Mucin Characteristics of Human Corneal-Limbal Epithelial Cells that Exclude the Rose Bengal Anionic Dye

    PubMed Central

    Argüeso, Pablo; Tisdale, Ann; Spurr-Michaud, Sandra; Sumiyoshi, Mika; Gipson, Ilene K.

    2005-01-01

    Purpose Rose bengal is an organic anionic dye used to assess damage of the ocular surface epithelium in ocular surface disease. It has been proposed that mucins have a protective role, preventing rose bengal staining of normal ocular surface epithelial cells. The current study was undertaken to evaluate rose bengal staining in a human corneal-limbal epithelial (HCLE) cell line known to produce and glycosylate membrane-associated mucins. Methods HCLE cells were grown to confluence in serum-free medium and switched to DMEM/F12 with 10% serum to promote differentiation. Immunolocalization of the membrane-associated mucins MUC1 and MUC16 and the T-antigen carbohydrate epitope was performed with the monoclonal antibodies HMFG-2 and OC125 and jacalin lectin, respectively. To assess dye uptake, cultures were incubated for 5 minutes with 0.1% rose bengal and photographed. To determine whether exclusion of negatively charged rose bengal requires a negative charge at the cell surface, cells were incubated with fluoresceinated cationized ferritin. The effect of hyperosmotic stress on rose bengal staining in vitro was evaluated by increasing the ion concentration (Ca+2 and Mg+2) in the rose bengal uptake assay. Results The cytoplasm and nucleus of confluent HCLE cells cultured in media without serum, lacking the expression of MUC16 but not MUC1, as well as human corneal fibroblasts, which do not express mucins, stained with rose bengal. Culture of HCLE cells in medium containing serum resulted in the formation of islands of stratified cells that excluded rose bengal. Apical cells of the stratified islands produced MUC16 and the T-antigen carbohydrate epitope on their apical surfaces. Colocalization experiments demonstrated that fluoresceinated cationized ferritin did not bind to these stratified cells, indicating that rose bengal is excluded from cells that lack negative charges. Increasing the amounts of divalent cations in the media reduced the cellular area protected

  12. Characterization of Rose Bengal binding to sinusoidal and bile canalicular plasma membrane from rat liver.

    PubMed

    Yachi, K; Sugiyama, Y; Sawada, Y; Iga, T; Ikeda, Y; Toda, G; Hanano, M

    1989-01-16

    The binding of Rose bengal, a model organic anion, to sinusoidal and bile canalicular membrane fractions isolated from rat liver was compared. The fluorescence change of Rose bengal after being bound to liver plasma membranes was utilized for measuring the binding. The dissociation constants (Kd = 0.1-0.12 microM) and the binding capacities (n = 11-15 nmol/mg protein) for Rose bengal are comparable between the two membrane fractions, although the n value for sinusoidal membrane is somewhat larger than that for bile canalicular membrane. The Rose bengal binding to both membrane fractions was inhibited by various organic anions at relatively low concentrations, i.e., the half-inhibition concentrations (IC50) for Indocyanine green, sulfobromophthalein, Bromophenol blue and 1-anilino-8-naphthalene sulfonate were 0.1, 100, 1.5-2.5 and 100 microM, respectively, while taurocholate did not inhibit the Rose bengal binding to either membrane fraction at these low concentration ranges. The type of inhibition of sulfobromophthalein and Indocyanine green for Rose bengal binding is different between the two membrane domains. That is, in sinusoidal and bile canalicular membrane fractions, these organic anions exhibit mixed-type and competitive-type inhibition, respectively. It was suggested that the fluorescence method using Rose bengal may provide a simple method for detecting the specific organic anion binding protein(s) in the liver plasma membrane.

  13. Rose Bengal Photothrombosis by Confocal Optical Imaging In Vivo: A Model of Single Vessel Stroke.

    PubMed

    Talley Watts, Lora; Zheng, Wei; Garling, R Justin; Frohlich, Victoria C; Lechleiter, James Donald

    2015-06-23

    In vivo imaging techniques have increased in utilization due to recent advances in imaging dyes and optical technologies, allowing for the ability to image cellular events in an intact animal. Additionally, the ability to induce physiological disease states such as stroke in vivo increases its utility. The technique described herein allows for physiological assessment of cellular responses within the CNS following a stroke and can be adapted for other pathological conditions being studied. The technique presented uses laser excitation of the photosensitive dye Rose Bengal in vivo to induce a focal ischemic event in a single blood vessel. The video protocol demonstrates the preparation of a thin-skulled cranial window over the somatosensory cortex in a mouse for the induction of a Rose Bengal photothrombotic event keeping injury to the underlying dura matter and brain at a minimum. Surgical preparation is initially performed under a dissecting microscope with a custom-made surgical/imaging platform, which is then transferred to a confocal microscope equipped with an inverted objective adaptor. Representative images acquired utilizing this protocol are presented as well as time-lapse sequences of stroke induction. This technique is powerful in that the same area can be imaged repeatedly on subsequent days facilitating longitudinal in vivo studies of pathological processes following stroke.

  14. Instantaneous radioiodination of rose bengal at room temperature and a cold kit therefor

    DOEpatents

    O'Brien, Jr., Harold A.; Hupf, Homer B.; Wanek, Philip M.

    1981-01-01

    The disclosure relates to the radioiodination of rose bengal at room temperature and a cold-kit therefor. A purified rose bengal tablet is stirred into acidified ethanol at or near room temperature, until a suspension forms. Reductant-free .sup.125 I.sup.- is added and the resulting mixture stands until the exchange label reaction occurs at room temperature. A solution of sterile isotonic phosphate buffer and sodium hydroxide is added and the final resulting mixture is sterilized by filtration.

  15. Systemic reduction of rice blast by means of photosensitizers

    USDA-ARS?s Scientific Manuscript database

    Acquired disease resistance of plants may be induced by exogenous reactive oxygen species or their sources. Certain compounds (photosensitizers) produce ROS at the expense of light energy. This study used photodynamic dyes bengal rose and methylene blue, which yield singlet oxygen, and mercaptopyrid...

  16. Instantaneous radioiodination of rose bengal at room temperature and a cold-kit therefor. [DOE patent application

    DOEpatents

    O'Brien, H. Jr.; Hupf, H.B.; Wanek, P.M.

    The disclosure relates to the radioiodination of rose bengal at room temperature and a cold-kit therefor. A purified rose bengal tablet is stirred into acidified ethanol at or near room temperature, until a suspension forms. Reductant-free /sup 125/I/sup -/ is added and the resulting mixture stands until the exchange label reaction occurs at room temperature. A solution of sterile isotonic phosphate buffer and sodium hydroxide is added and the final resulting mixture is sterilized by filtration.

  17. Elicitation of spreading depression by rose bengal photodynamic action.

    PubMed

    Netto, M; Martins-Ferreira, H

    1989-08-01

    Spreading depression refers to a slowly propagating depression of the ordinary electrical activity of the nervous tissue. It can be elicited by different types of physical or chemical non-specific stimuli. Various evidences suggest that transient alterations of cell membranes are involved. For this reason, and considering the action of free radicals on cell membranes, the elicitation of the reaction by dye photoactivation has been investigated. Isolated chick retina superfused in the dark with Ringer solution was able to regularly exhibit spreading depression when submitted to 1 microM rose bengal pulse of 5 min in duration, followed by 2.1 x 10(4) to 4.2 x 10(4) Jm-2 light pulse. The phenomenon was monitored either by visual inspection of the light-scattering milky wave that accompanies the reaction or by recording its characteristic slow voltage variation. The reaction was not triggered if the retina, superfused with the dye, was (a) maintained in the dark; (b) illuminated with red light (3.75 x 10(2) to 2.25 x 10(4) Jm-2), or (c) stimulated by white light but superfused with nitrogen-saturated solutions. It is concluded that, under the present conditions, the elicitation of spreading depression is contingent on the photoactivation of rose bengal in the presence of oxygen.

  18. Study the performance of photogalvanic cells for solar energy conversion and storage: Rose Bengal-D-Xylose-NaLS system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gangotri, K.M.; Bhimwal, Mahesh Kumar

    2010-07-15

    The Rose Bengal is used as photosensitizer with D-Xylose as reductant and sodium lauryl sulphate (NaLS) as surfactant for the enhancement of the conversion efficiency and storage capacity of photogalvanic cell for its commercial viability. The observed value of the photogeneration of photopotential was 885.0 mV and photocurrent was 460.0 {mu}A whereas maximum power of the cell was 407.10 {mu}W. The observed power at power point was 158.72 {mu}W and the conversion efficiency was 1.52%. The fill factor 0.3151 was experimentally determined at the power point of the cell. The rate of initial generation of photocurrent was 63.88 {mu}A min{supmore » -1}. The photogalvanic cell so developed can work for 145.0 min in dark on irradiation for 165.0 min, i.e. the storage capacity of the photogalvanic cell is 87.87%. A simple mechanism for the photogeneration of photocurrent has also been proposed. (author)« less

  19. Singlet oxygen-sensitized delayed fluorescence of common water-soluble photosensitizers.

    PubMed

    Scholz, Marek; Dědic, Roman; Breitenbach, Thomas; Hála, Jan

    2013-10-01

    Six common water-soluble singlet oxygen ((1)O2) photosensitizers - 5,10,15,20-tetrakis(1-methyl-4-pyridinio) porphine (TMPyP), meso-tetrakis(4-sulfonathophenyl)porphine (TPPS4), Al(III) phthalocyanine chloride tetrasulfonic acid (AlPcS4), eosin Y, rose bengal, and methylene blue - were investigated in terms of their ability to produce delayed fluorescence (DF) in solutions at room temperature. All the photosensitizers dissolved in air-saturated phosphate buffered saline (PBS, pH 7.4) exhibit easily detectable DF, which can be nearly completely quenched by 10 mM NaN3, a specific (1)O2 quencher. The DF kinetics has a biexponential rise-decay character in a microsecond time domain. Therefore, we propose that singlet oxygen-sensitized delayed fluorescence (SOSDF), where the triplet state of a photosensitizer reacts with (1)O2 giving rise to an excited singlet state of the photosensitizer, is the prevailing mechanism. It was confirmed by additional evidence, such as a monoexponential decay of triplet-triplet transient absorption kinetics, dependence of SOSDF kinetics on oxygen concentration, absence of SOSDF in a nitrogen-saturated sample, or the effect of isotopic exchange H2O-D2O. Eosin Y and AlPcS4 show the largest SOSDF quantum yield among the selected photosensitizers, whereas rose bengal possesses the highest ratio of SOSDF intensity to prompt fluorescence intensity. The rate constant for the reaction of triplet state with (1)O2 giving rise to the excited singlet state of photosensitizer was estimated to be ~/>1 × 10(9) M(-1) s(-1). SOSDF kinetics contains information about both triplet and (1)O2 lifetimes and concentrations, which makes it a very useful alternative tool for monitoring photosensitizing and (1)O2 quenching processes, allowing its detection in the visible spectral region, utilizing the photosensitizer itself as a (1)O2 probe. Under our experimental conditions, SOSDF was up to three orders of magnitude more intense than the infrared (1)O2

  20. Polymer-Immobilized Photosensitizers for Continuous Eradication of Bacteria

    PubMed Central

    Valkov, Anton; Nakonechny, Faina; Nisnevitch, Marina

    2014-01-01

    The photosensitizers Rose Bengal (RB) and methylene blue (MB), when immobilized in polystyrene, were found to exhibit high antibacterial activity in a continuous regime. The photosensitizers were immobilized by dissolution in chloroform, together with polystyrene, with further evaporation of the solvent, yielding thin polymeric films. Shallow reservoirs, bottom-covered with these films, were used for constructing continuous-flow photoreactors for the eradication of Gram-positive Staphylococcus aureus, Gram-negative Escherichia coli and wastewater bacteria under illumination with visible white light using a luminescent lamp at a 1.8 mW·cm−2 fluence rate. The bacterial concentration decreased by two to five orders of magnitude in separate reactors with either immobilized RB or MB, as well as in three reactors connected in series, which contained one of the photosensitizers. Bacterial eradication reached more than five orders of magnitude in two reactors connected in series, where the first reactor contained immobilized RB and the second contained immobilized MB. PMID:25158236

  1. Fe3O4@Au@mSiO2 as an enhancing nanoplatform for Rose Bengal photodynamic activity.

    PubMed

    Rosa-Pardo, I; Roig-Pons, M; Heredia, A A; Usagre, J V; Ribera, A; Galian, R E; Pérez-Prieto, J

    2017-07-27

    A novel nanoplatform composed of three types of materials with different functionalities, specifically core-shell Fe 3 O 4 @Au nanoparticles encapsulated near the outer surface of mesoporous silica (mSiO 2 ) nanoparticles, has been successfully synthesised and used to enhance the efficiency of a photosensitiser, namely Rose Bengal, in singlet oxygen generation. Fe 3 O 4 is responsible for the unusual location of the Fe 3 O 4 @Au nanoparticle, while the plasmonic shell acts as an optical antenna. In addition, the mesoporous silica matrix firmly encapsulates Rose Bengal by chemical bonding inside the pores, thus guaranteeing its photostability, and in turn making the nanosystem biocompatible. Moreover, the silica surface of the nanoplatform ensures further functionalisation on demand.

  2. I-131 rose bengal excretion test is not dead

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Antico, V.F.; Denhartog, P.; Ash, J.M.

    1985-03-01

    One hundred and thirty I-131 Rose Bengal Excretion Studies (RBI) were performed on 84 patients over nine years. In 90% (56/60) of cases with biliary atresia, the 72-hour RBI was less than or equal to 7%. In only 12.5% (3/24) of cases with neonatal hepatitis was the 72-hour RBI less than or equal to 7%. The accuracy of the test was 91% with a specificity of 88%. Thirty patients later were studied following a Kasai procedure. The RBI test reliably predicted the patency of the anastomosis. The authors conclude that the 72-hour RBI is a reliable test in the diagnosismore » of biliary atresia and in the documentation of biliary patency following surgery, provided adequate care is taken in stool collection and measurement.« less

  3. Reactive oxygen species explicit dosimetry (ROSED) of a type 1 photosensitizer

    NASA Astrophysics Data System (ADS)

    Ong, Yi Hong; Kim, Michele M.; Huang, Zheng; Zhu, Timothy C.

    2018-02-01

    Type I photodynamic therapy (PDT) is based on the use of photochemical reactions mediated through an interaction between a tumor-selective photosensitizer, photoexcitation with a specific wavelength of light, and production of reactive oxygen species (ROS). The goal of this study is to develop a model to calculate reactive oxygen species concentration ([ROS]rx) after Tookad®-mediated vascular PDT. Mice with radiation-induced fibrosarcoma (RIF) tumors were treated with different light fluence and fluence rate conditions. Explicit measurements of photosensitizer drug concentration were made via diffuse reflective absorption spectrum using a contact probe before and after PDT. Blood flow and tissue oxygen concentration over time were measured during PDT as a mean to validate the photochemical parameters for the ROSED calculation. Cure index was computed from the rate of tumor regrowth after treatment and was compared against three calculated dose metrics: total light fluence, PDT dose, reacted [ROS]rx. The tumor growth study demonstrates that [ROS]rx serves as a better dosimetric quantity for predicting treatment outcome, as a clinically relevant tumor growth endpoint.

  4. Corneal Crosslinking With Rose Bengal and Green Light: Efficacy and Safety Evaluation.

    PubMed

    Zhu, Hong; Alt, Clemens; Webb, Robert H; Melki, Samir; Kochevar, Irene E

    2016-09-01

    To evaluate crosslinking of cornea in vivo using green light activation of Rose Bengal (RGX) and assess potential damaging effects of the green light on retina and iris. Corneas of Dutch belted rabbits were de-epithelialized, then stained with Rose Bengal and exposed to green light, or not further treated. Corneal stiffness was measured by uniaxial tensiometry. Re-epithelialization was assessed by fluorescein fluorescence. Keratocytes were counted on hematoxylin and eosin (H&E)-stained sections, and iris cell damage was assessed by lactate dehydrogenase staining. Thermal effects on the blood-retinal barrier (BRB) were assessed by fluorescein angiography and those on photoreceptors, retinal pigment epithelium (RPE), and choriocapillaris by light microscopy and transmission electron microscopy. RGX (10-min irradiation; 150 J/cm) increased corneal stiffness 1.9-fold on day 1 (1.25 ± 0.21 vs. 2.38 ± 0.59 N/mm; P = 0.036) and 2.8-fold compared with controls on day 28 (1.70 ± 0.74 vs. 4.95 ± 1.86 N/mm; P = 0.003). Keratocytes decreased only in the anterior stroma on day 1 (24.0 ± 3.0 vs. 3.67 ± 4.73, P = 0.003) and recovered by day 28 (37.7 ± 8.9 vs. 34.5 ± 2.4, P = 0.51). Iris cells were not thermally damaged. No evidence of BRB breakdown was detected on days 1 or 28. Retina from RGX-treated eyes seemed normal with RPE cells showing intact nuclei shielded apically by melanosomes, morphologically intact photoreceptor outer segments, normal outer nuclear layer thickness, and choriocapillaris containing intact erythrocytes. The substantial corneal stiffening produced by RGX together with the lack of significant effects on keratocytes and no evidence for retina or iris damage suggest that RGX-initiated corneal crosslinking may be a safe, rapid, and effective treatment.

  5. Photosensitized degradation of losartan potassium in an extemporaneous suspension formulation.

    PubMed

    Seburg, Randal A; Ballard, John M; Hwang, Tsang-Lin; Sullivan, Caitlin M

    2006-10-11

    During development of an extemporaneous suspension formulation for losartan potassium, previously unknown degradation products were observed in experimental suspensions prepared in a commercial cherry syrup vehicle. These degradates increased rapidly when analytical solutions prepared from that suspension were exposed to ambient light. The structures of the degradates were determined using a combination of preparative HPLC, LC/MS, (13)C and (1)H NMR (1D and 2D), and mechanistic chemistry. Each degradate results from destruction of the imidazole ring of losartan. Formation of the two major degradates required exposure to light (UV or visible) and the presence of oxygen. Experiments using Rose Bengal (a singlet oxygen photosensitizer) and 1,4-diazabicyclooctane (DABCO; a singlet oxygen quencher) established that the major photodegradates are formed via the intermediacy of singlet oxygen. The identity of the photosensitizer in the formulation was not unequivocally determined; however, the experiments implicated the artificial flavoring in fulfilling this role.

  6. Physical Stability, Autoxidation, and Photosensitized Oxidation of ω-3 Oils in Nanoemulsions Prepared with Natural and Synthetic Surfactants.

    PubMed

    Uluata, Sibel; McClements, D Julian; Decker, Eric A

    2015-10-28

    The food industry is interested in the utilization of nanoemulsions stabilized by natural emulsifiers, but little research has been conducted to determine the oxidative stability of such emulsions. In this study, two natural (lecithin and quillaja saponin) and two synthetic (Tween 80 and sodium dodecyl sulfate) surfactants were used to fabricate omega-3 nanoemulsion using high pressure homogenization (microfluidization). Initially, all the nanoemulsions contained small (d from 45 to 89 nm) and anionic (ζ-potential from -8 to -65 mV) lipid droplets (pH 7). The effect of pH, ionic strength, and temperature on the physical stability of the nanoemulsion system was examined. Nanoemulsion stabilized with Tween 80, quillaja saponin, or sodium dodecyl sulfate (SDS) exhibited no major changes in particle size or visible creaming in the pH range of 3 to 8. All nanoemulsions were relatively stable to salt addition (0 to 500 mM NaCl, pH 7.0). Nanoemulsions stabilized with SDS and quillaja saponin were stable to heating (30 to 90 °C). The impact of surfactant type on lipid oxidation was determined in the presence and absence of the singlet oxygen photosensitizers, riboflavin, and rose bengal. Riboflavin and rose bengal accelerated lipid oxidation when compare to samples without photosensitizers. Lipid hydroperoxide formation followed the order Tween 80 > SDS > lecithin > quillaja saponin, and propanal formation followed the order lecithin > Tween 80 > SDS > quillaja saponin at 37 °C for autoxidation. The same order of oxidative stability was observed in the presence of photosensitized oxidation promoted by riboflavin. Quillaja saponin consistently produced the most oxidatively stable emulsions, which could be due to its high free radical scavenging capacity.

  7. Corneal Resistance to Keratolysis After Collagen Crosslinking With Rose Bengal and Green Light.

    PubMed

    Fadlallah, Ali; Zhu, Hong; Arafat, Samer; Kochevar, Irene; Melki, Samir; Ciolino, Joseph B

    2016-12-01

    The purpose of this study was to evaluate the resistance to degradation by collagenase A of corneas that have been crosslinked with Rose Bengal and green light (RGX). The ex vivo crosslinking procedure was performed on enucleated rabbit corneas. Corneas were deepithelialized after applying 30% alcohol. Corneas were stained with Rose Bengal (RB, 0.1%) for 2 minutes and then exposed to green light (532 nm) at 0.25 W/cm2 for times to deliver doses of 50, 100, 150, or 200 J/cm2 (n = 5 per group). Five corneas were pretreated with riboflavin solution (0.1% riboflavin) for 15 minutes and irradiated with ultraviolet A (UVA) light (370 nm, 3 mW/cm2) for 30 minutes. Five corneas underwent only de-epithelialization and were otherwise untreated. Five corneas were stained with RB without light exposure. The central corneas of each group was removed with a 8.5-mm trephine and incubated at 37°C in 0.3% collagenase A solution. Time to dissolution of each cornea was compared across treatments. Corneas treated with RGX were treated with light fluences of 50, 100, 150, and 200 J/cm2; these corneas dissolved completely at 8.3 ± 1.2, 11.1 ± 1.4, 12.4 ± 1.7, and 15.7 ± 1.8 hours, respectively. Corneas treated by riboflavin and UVA light dissolved at 15.7 ± 1.7 hours, and nontreated corneas dissolved at 6.1 ± 1.3 hours. Corneas treated with only RB (no green light) dissolved at 9.3 ± 1.7 hours. Compared with the untreated corneas, all of the RB groups and the riboflavin-UVA-treated group of corneas degraded statistically significantly slower than untreated corneas (P < 0.05). Crosslinking with RGX increased corneal resistance to digestion by collagenase comparable to that produced by riboflavin and UVA treatment.

  8. Morphology dependent catalytic activity of TiO{sub 2} nanostructures towards photodegradation of Rose Bengal

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Malik, Ritu; Kumar, Ashok; Rana, Pawan S., E-mail: drpawansrana.phy@dcrustm.org

    2015-08-28

    This work deals with the synthesis of TiO{sub 2} nanostructures using sol-gel and hydrothermal method for evaluating their photodegradation performance towards decolorization of Rose Bengal (RB). A combination of characterization techniques including X-ray diffraction (XRD), Field emission scanning electron microscopy (FESEM) and UV–Vis spectroscopy were utilized to evaluate the structural, morphological and optical properties of the obtained nanostructures. It was observed that the TiO{sub 2} nanoparticles prepared using hydrothermal method were highly crystalline and possess higher band gap value, even when same conditions of temperature, pressure, precursor ratios and solvent amount was kept constant while synthesizing TiO{sub 2} nanostructures viamore » sol-gel method. The obvious effect of porous morphology exhibited by TiO{sub 2} nanoparticles prepared using hydrothermal route is reflected in its decolorization performance whereby 92.5% of the RB dye solution was degraded in 70 min of irradiation time.« less

  9. Green-fuel-mediated synthesis of self-assembled NiO nano-sticks for dual applications—photocatalytic activity on Rose Bengal dye and antimicrobial action on bacterial strains

    NASA Astrophysics Data System (ADS)

    Iyyappa Rajan, P.; Vijaya, J. Judith; Jesudoss, S. K.; Kaviyarasu, K.; Kennedy, L. John; Jothiramalingam, R.; Al-Lohedan, Hamad A.; Vaali-Mohammed, Mansoor-Ali

    2017-08-01

    With aim of promoting the employability of green fuels in the synthesis of nano-scaled materials with new kinds of morphologies for multiple applications, successful synthesis of self-assembled NiO nano-sticks was achieved through a 100% green-fuel-mediated hot-plate combustion reaction. The synthesized NiO nano-sticks show excellent photocatalytic activity on Rose Bengal dye and superior antibacterial potential towards both Gram-positive and Gram-negative bacteria.

  10. Evaluating the Effects of Riboflavin/UV-A and Rose-Bengal/Green Light Cross-Linking of the Rabbit Cornea by Noncontact Optical Coherence Elastography

    PubMed Central

    Singh, Manmohan; Li, Jiasong; Han, Zhaolong; Vantipalli, Srilatha; Liu, Chih-Hao; Wu, Chen; Raghunathan, Raksha; Aglyamov, Salavat R.; Twa, Michael D.; Larin, Kirill V.

    2016-01-01

    Purpose The purpose of this study was to use noncontact optical coherence elastography (OCE) to evaluate and compare changes in biomechanical properties that occurred in rabbit cornea in situ after corneal collagen cross-linking by either of two techniques: ultraviolet-A (UV-A)/riboflavin or rose-Bengal/green light. Methods Low-amplitude (≤10 μm) elastic waves were induced in mature rabbit corneas by a focused air pulse. Elastic wave propagation was imaged by a phase-stabilized swept source OCE (PhS-SSOCE) system. Corneas were then cross-linked by either of two methods: UV-A/riboflavin (UV-CXL) or rose-Bengal/green light (RGX). Phase velocities of the elastic waves were fitted to a previously developed modified Rayleigh-Lamb frequency equation to obtain the viscoelasticity of the corneas before and after the cross-linking treatments. Micro-scale depth-resolved phase velocity distribution revealed the depth-wise heterogeneity of both cross-linking techniques. Results Under standard treatment settings, UV-CXL significantly increased the stiffness of the corneas by ∼47% (P < 0.05), but RGX did not produce statistically significant increases. The shear viscosities were unaffected by either cross-linking technique. The depth-wise phase velocities showed that UV-CXL affected the anterior ∼34% of the corneas, whereas RGX affected only the anterior ∼16% of the corneas. Conclusions UV-CXL significantly strengthens the cornea, whereas RGX does not, and the effects of cross-linking by UV-CXL reach deeper into the cornea than cross-linking effects of RGX under similar conditions. PMID:27409461

  11. Light-triggered liposomal cargo delivery platform incorporating photosensitizers and gold nanoparticles for enhanced singlet oxygen generation and increased cytotoxicity

    NASA Astrophysics Data System (ADS)

    Kautzka, Zofia; Clement, Sandhya; Goldys, Ewa M.; Deng, Wei

    2018-02-01

    We developed light-triggered liposomes incorporating gold nanoparticles and Rose Bengal (RB), a well-known photosensitizer used for photodynamic therapy. Singlet oxygen generated by these liposomes with 532 nm light illumination was characterized by adjusting the molar ratio of lipids and gold nanoparticles while keeping the amount of RB constant. Gold nanoparticles were found to enhance the singlet oxygen generation rate, with a maximum enhancement factor of 1.75 obtained for the molar ratio of HSPC: PE-NH2: gold of 57:5:17 compared with liposomes loaded with RB alone. The experimental results could be explained by the local electric field enhancement caused by gold nanoparticles. We further assessed cellular cytotoxicity of these liposomes by encapsulating an antitumor drug, doxorubicin (Dox); such Dox loaded liposomes were applied to human colorectal cancer cells, HCT116, and exposed to light. Gold-loaded liposomes containing RB and Dox where Dox release was triggered by light were found to exhibit higher cytotoxicity, compared to the liposomes loaded with RB and Dox alone. Our results indicate that gold-loaded liposomes incorporating photosensitizers may have improved therapeutic efficacy in photodynamic therapy and chemotherapy.

  12. Potassium iodide potentiates antimicrobial photodynamic inactivation mediated by Rose Bengal: in vitro and in vivo studies

    NASA Astrophysics Data System (ADS)

    Wen, Xiang; Zhang, Xiaoshen; Szewczyk, Grzegorz; ElHussien, Ahmed; Huang, Ying-Ying; Sarna, Tadeusz; Hamblin, Michael R.

    2018-02-01

    Rose Bengal (RB) is a halogenated xanthene dye that has been used to mediate antimicrobial photodynamic inactivation. While highly active against Gram-positive bacteria, RB is largely inactive in killing Gram-negative bacteria. We have discovered that addition of the non-toxic salt potassium iodide (100mM) potentiates green light (540nm)-mediated killing by up to six extra logs with Gramnegative bacteria Escherichia coli and Pseudomonas aeruginosa,Gram-positive methicillin resistant Staphylococcus aureus, and fungal yeast Candida albicans. The mechanism is proposed to be singlet oxygen addition to iodide anion to form peroxyiodide, which decomposes into radicals, finally forms hydrogen peroxide and molecular iodine. The effects of these different bactericidal species can be teased apart by comparing killing in three different scenarios: (1) cells+RB+KI are mixed together then illuminated with green light; (2) cells+RB are centrifuged then KI added then green light; (3) RB+KI+green light then cells added after light. We showed that KI could potentiate RBPDT in a mouse model of skin abrasions infected with bioluminescent P.aeruginosa.

  13. Comparison of continuous versus pulsed photodynamic antimicrobial therapy for inhibition of fungal keratitis isolates in vitro (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Nolan, Nicholas; Durkee, Heather A.; Aguilar, Mariela C.; Arboleda, Alejandro; Relhan, Nidhi; Martinez, Anna; Rowaan, Cornelis; Gonzalez, Alex; Alawa, Karam A.; Amescua, Guillermo; Flynn, Harry W.; Miller, Darlene; Parel, Jean-Marie A.

    2017-02-01

    Fungal keratitis can lead to pain and impaired vision. Current treatment options include antifungal agents and therapeutic penetrating keratoplasty. An emerging option for the management of keratitis is photodynamic antimicrobial therapy (PDAT) which uses a photosensitizer rose bengal activated with green light. Utilizing a pulsed irradiation, rather than the standard continuous irradiation may have a similar antimicrobial effect with less total energy. This study is to compare pulsed and continuous rose bengal mediated PDAT for inhibition of six fungal isolates on agar plates: Fusarium solani, Fusarium keratoplasticum, Aspergillus fumigatus, Candida albicans, Paecilomyces variotti, and Pseudoallescheria boydii. Isolates were mixed with 0.1% rose bengal and exposed to three irradiation conditions: (1) 30-minute continuous (10.8J/cm2), (2) 15-minute continuous (5.4J/cm2), (3) 30-minute pulsed (5.4J/cm2). Plates were photographed at 72 hours and analyzed with custom software. At 72 hours, 30-minute continuous rose bengal mediated PDAT inhibited all six fungal species. Fungal inhibition was analogous between 30-minute continuous and 30-minute pulsed test groups, with the exception of A. fumigatus. The 15-minute continuous irradiation was less effective when compared to both 30-minute continuous and 30-minute pulsed groups. These in vitro results demonstrate the potential strength of pulsed rose bengal mediated PDAT as an adjunct treatment modality for fungal keratitis.

  14. Synthesis and characterization of gadolinium nanosheets with bound rose bengal: potential use in photodynamic therapy and MRI

    NASA Astrophysics Data System (ADS)

    Stefanakis, Dimitrios; Seimenis, Ioannis; Ghanotakis, Demetrios

    2014-11-01

    Gadolinium (Gd) is a trivalent paramagnetic element, making it useful as a contrast agent for magnetic resonance imaging (MRI). Gd2(OH)5NO3· xH2O belongs to a new family of nanosheets. The advantages of these materials are their relatively small size, paramagnetic behavior, stability, lack of toxicity and highly ordered structure. In the present study, Gd2(OH)5NO3 nanosheets were functionalized with amino groups and modified with the photosensitiser rose bengal (RB). This surface modification makes possible the use of the nanosheets in photodynamic therapy. The coated nanosheets were characterized with X-ray diffraction, fourier transform infrared spectroscopy and UV-Vis spectroscopy, as well as transmission electron microscopy. The possibility of using these nanosheets as potential spin-lattice ( T 1) and spin-spin relaxation ( T 2) contrast agents in MRI was evaluated at 1.5 T. Finally, the ability of Gd2(OH)5NO3-RB to catalyze photooxidization reactions was examined using nuclear magnetic resonance (1H NMR) and gas chromatography-mass spectrometry (GC/MS).

  15. Light-triggered liposomal cargo delivery platform incorporating photosensitizers and gold nanoparticles for enhanced singlet oxygen generation and increased cytotoxicity.

    PubMed

    Kautzka, Zofia; Clement, Sandhya; Goldys, Ewa M; Deng, Wei

    2017-01-01

    We developed light-triggered liposomes incorporating 3-5 nm hydrophobic gold nanoparticles and Rose Bengal (RB), a well-known photosensitizer used for photodynamic therapy. Singlet oxygen generated by these liposomes with 532 nm light illumination was characterized for varying the molar ratio of lipids and gold nanoparticles while keeping the amount of RB constant. Gold nanoparticles were found to enhance the singlet oxygen generation rate, with a maximum enhancement factor of 1.75 obtained for the molar ratio of hydrogenated soy l-α-phosphatidylcholine:1,2-dioleoyl- sn -glycero-3-phosphoethanolamine- N -(hexanoylamine):gold of 57:5:17 compared with liposomes loaded with RB alone. The experimental results could be explained by the local electric field enhancement caused by gold nanoparticles. We further assessed cellular cytotoxicity of gold-loaded liposomes by encapsulating an antitumor drug, doxorubicin (Dox); such Dox-loaded liposomes were applied to human colorectal cancer cells (HCT116) and exposed to light. Gold-loaded liposomes containing RB and Dox where Dox release was triggered by light were found to exhibit higher cytotoxicity compared with the liposomes loaded with RB and Dox alone. Our results indicate that gold-loaded liposomes incorporating photosensitizers may serve as improved agents in photodynamic therapy and chemotherapy.

  16. Light-triggered liposomal cargo delivery platform incorporating photosensitizers and gold nanoparticles for enhanced singlet oxygen generation and increased cytotoxicity

    PubMed Central

    Kautzka, Zofia; Clement, Sandhya; Goldys, Ewa M; Deng, Wei

    2017-01-01

    We developed light-triggered liposomes incorporating 3–5 nm hydrophobic gold nanoparticles and Rose Bengal (RB), a well-known photosensitizer used for photodynamic therapy. Singlet oxygen generated by these liposomes with 532 nm light illumination was characterized for varying the molar ratio of lipids and gold nanoparticles while keeping the amount of RB constant. Gold nanoparticles were found to enhance the singlet oxygen generation rate, with a maximum enhancement factor of 1.75 obtained for the molar ratio of hydrogenated soy l-α-phosphatidylcholine:1,2-dioleoyl-sn-glycero-3-phosphoethanolamine-N-(hexanoylamine):gold of 57:5:17 compared with liposomes loaded with RB alone. The experimental results could be explained by the local electric field enhancement caused by gold nanoparticles. We further assessed cellular cytotoxicity of gold-loaded liposomes by encapsulating an antitumor drug, doxorubicin (Dox); such Dox-loaded liposomes were applied to human colorectal cancer cells (HCT116) and exposed to light. Gold-loaded liposomes containing RB and Dox where Dox release was triggered by light were found to exhibit higher cytotoxicity compared with the liposomes loaded with RB and Dox alone. Our results indicate that gold-loaded liposomes incorporating photosensitizers may serve as improved agents in photodynamic therapy and chemotherapy. PMID:28203076

  17. Model studies on the photosensitized isomerization of bixin.

    PubMed

    Montenegro, Mariana A; Rios, Alessandro de O; Mercadante, Adriana Z; Nazareno, Mónica A; Borsarelli, Claudio D

    2004-01-28

    The photosensitized isomerization reaction of the natural cis carotenoid bixin (methyl hydrogen 9'-cis-6, 6'-diapocarotene-6, 6'-dioate) with rose bengal or methylene blue as the sensitizer in acetonitrile/methanol (1:1) solution was studied using UV-vis spectroscopy, high-performance liquid chromatography (HPLC), and time-resolved spectroscopic techniques, such as laser-flash photolysis and singlet oxygen phosphorescence detection. In both N(2)- and air-saturated solutions, the main product formed was all-trans-bixin. The observed isomerization rate constants, k(obs), decreased in the presence of air or with increase in the bixin concentration, suggesting the participation of the excited triplet state of bixin, (3)Bix, as precursor of the cis--> trans process. On the other hand, bixin solutions in the absence of sensitizer and/or light did not degrade, indicating that the ground state of bixin is stable to thermal isomerization at room temperature. Time-resolved spectroscopic experiments confirmed the formation of the excited triplet state of bixin and its deactivation by ground state bixin and molecular oxygen quenching processes. The primary isomerization products only degraded in the presence of air and under prolonged illumination conditions, probably due to the formation of oxidation products by reaction with singlet molecular oxygen. An energy-transfer mechanism was used to explain the observed results for the bixin transformations, and the consequences for food color are discussed.

  18. Preparation of PLGA/Rose Bengal colloidal particles by double emulsion and layer-by-layer for breast cancer treatment.

    PubMed

    Loya-Castro, María F; Sánchez-Mejía, Mariana; Sánchez-Ramírez, Dante R; Domínguez-Ríos, Rossina; Escareño, Noé; Oceguera-Basurto, Paola E; Figueroa-Ochoa, Édgar B; Quintero, Antonio; Del Toro-Arreola, Alicia; Topete, Antonio; Daneri-Navarro, Adrián

    2018-05-15

    The use of colloidal particles (CPs) in the transport of drugs is developing rapidly thanks to its effectiveness and biosafety, especially in the treatment of various types of cancer. In this study Rose Bengal/PLGA CPs synthesized by double emulsion (W/O/W) and by electrostatic adsorption (layer-by-layer), were characterized and evaluated as potential breast cancer treatment. CPs were evaluated in terms of size, zeta potential, drug release kinetics and cell viability inhibition efficacy with the triple negative breast cancer cell line HCC70. The results showed that both types of CPs can be an excellent alternative to conventional cancer treatment by taking advantage of the enhanced permeation and retention (EPR) effect, manifested by solid tumors; however, the double emulsion CPs showed more suitable delivery times of up to 60% within two days, while layer-by-layer showed fast release of 50% in 90 min. Both types of CPs were capable to decrease cell viability, which encourage us to further testing in in vivo models to prove their efficacy and feasible use in the treatment of triple negative breast cancer. Copyright © 2018 Elsevier Inc. All rights reserved.

  19. Potassium Iodide Potentiates Antimicrobial Photodynamic Inactivation Mediated by Rose Bengal in In Vitro and In Vivo Studies.

    PubMed

    Wen, Xiang; Zhang, Xiaoshen; Szewczyk, Grzegorz; El-Hussein, Ahmed; Huang, Ying-Ying; Sarna, Tadeusz; Hamblin, Michael R

    2017-07-01

    Rose bengal (RB) is a halogenated xanthene dye that has been used to mediate antimicrobial photodynamic inactivation for several years. While RB is highly active against Gram-positive bacteria, it is largely inactive in killing Gram-negative bacteria. We have discovered that addition of the nontoxic salt potassium iodide (100 mM) potentiates green light (540-nm)-mediated killing by up to 6 extra logs with the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa , the Gram-positive bacterium methicillin-resistant Staphylococcus aureus , and the fungal yeast Candida albicans The mechanism is proposed to be singlet oxygen addition to iodide anion to form peroxyiodide, which decomposes into radicals and, finally, forms hydrogen peroxide and molecular iodine. The effects of these different bactericidal species can be teased apart by comparing the levels of killing achieved in three different scenarios: (i) cells, RB, and KI are mixed together and then illuminated with green light; (ii) cells and RB are centrifuged, and then KI is added and the mixture is illuminated with green light; and (iii) RB and KI are illuminated with green light, and then cells are added after illumination with the light. We also showed that KI could potentiate RB photodynamic therapy in a mouse model of skin abrasions infected with bioluminescent P. aeruginosa . Copyright © 2017 American Society for Microbiology.

  20. Potassium Iodide Potentiates Antimicrobial Photodynamic Inactivation Mediated by Rose Bengal in In Vitro and In Vivo Studies

    PubMed Central

    Wen, Xiang; Zhang, Xiaoshen; Szewczyk, Grzegorz; El-Hussein, Ahmed; Huang, Ying-Ying; Sarna, Tadeusz

    2017-01-01

    ABSTRACT Rose bengal (RB) is a halogenated xanthene dye that has been used to mediate antimicrobial photodynamic inactivation for several years. While RB is highly active against Gram-positive bacteria, it is largely inactive in killing Gram-negative bacteria. We have discovered that addition of the nontoxic salt potassium iodide (100 mM) potentiates green light (540-nm)-mediated killing by up to 6 extra logs with the Gram-negative bacteria Escherichia coli and Pseudomonas aeruginosa, the Gram-positive bacterium methicillin-resistant Staphylococcus aureus, and the fungal yeast Candida albicans. The mechanism is proposed to be singlet oxygen addition to iodide anion to form peroxyiodide, which decomposes into radicals and, finally, forms hydrogen peroxide and molecular iodine. The effects of these different bactericidal species can be teased apart by comparing the levels of killing achieved in three different scenarios: (i) cells, RB, and KI are mixed together and then illuminated with green light; (ii) cells and RB are centrifuged, and then KI is added and the mixture is illuminated with green light; and (iii) RB and KI are illuminated with green light, and then cells are added after illumination with the light. We also showed that KI could potentiate RB photodynamic therapy in a mouse model of skin abrasions infected with bioluminescent P. aeruginosa. PMID:28438946

  1. Effect of red dyes on blue light phototoxicity against VSC producing bacteria in an experimental oral biofilm.

    PubMed

    Jeffet, U; Nasrallah, R; Sterer, N

    2016-11-21

    Oral malodour is considered to be caused mainly by the production of volatile sulfide compounds (VSC) by anaerobic Gram-negative oral bacteria. Previous study showed that these bacteria were susceptible to blue light (wavelengths of 400-500 nm). In the present study, we tested the effect of blue light in the presence of red dyes on malodour production in an experimental oral biofilm. Biofilms were exposed to a plasma-arc light source for 30, 60, and 120 s (i.e. fluences of 41, 82, and 164 J cm -2 , respectively) with the addition of erythrosine, natural red and rose bengal (0.01, 0.1 and 1% w/v). Following light exposure biofilm samples were examined for malodour production (Odour judge), VSC production (Halimeter ™ ), VSC producing bacteria quantification using microscopy sulfide assay (MSA) and reactive oxygen species (ROS) production. Results showed that the exposure of experimental oral biofilm to blue light in the presence of rose bengal caused an increased reduction in VSC and malodour production concomitant with an increase in ROS production. These results suggest that rose bengal might be effective as a blue light photosensitizer against VSC producing bacteria.

  2. Site-Directed Photoproteolysis of 8-Oxoguanine DNA Glycosylase 1 (OGG1) by Specific Porphyrin-Protein Probe Conjugates: A Strategy to Improve the Effectiveness of Photodynamic Therapy for Cancer

    PubMed Central

    Conlon, Kimberly A.; Berrios, Miguel

    2007-01-01

    The specific light-induced, non-enzymatic photolysis of mOGG1 by porphyrin-conjugated or rose bengal-conjugated streptavidin and porphyrin-conjugated or rose bengal-conjugated first specific or secondary anti-IgG antibodies is reported. The porphyrin chlorin e6 and rose bengal were conjugated to either streptavidin, rabbit anti-mOGG1 primary specific antibody fractions or goat anti-rabbit IgG secondary antibody fractions. Under our experimental conditions, visible light of wavelengths greater than 600 nm induced the non-enzymatic degradation of mOGG1 when this DNA repair enzyme either directly formed a complex with chlorin e6-conjugated anti-mOGG1 primary specific antibodies or indirectly formed complexes with either streptavidin-chlorin e6 conjugates and biotinylated first specific anti-mOGG1 antibodies or first specific anti-mOGG1antibodies and chlorin e6-conjugated anti-rabbit IgG secondary antibodies. Similar results were obtained when rose bengal was used as photosensitizer instead of chlorine e6. The rate of the photochemical reaction of mOGG1 site-directed by all three chlorine e6 antibody complexes was not affected by the presence of the singlet oxygen scavenger sodium azide. Site-directed photoactivatable probes having the capacity to generate reactive oxygen species (ROS) while destroying the DNA repair system in malignant cells and tumors may represent a powerful strategy to boost selectivity, penetration and efficacy of current photodynamic (PDT) therapy methodologies. PMID:17251034

  3. Rose bengal in poly(2-hydroxyethyl methacrylate) thin films: self-quenching by photoactive energy traps

    NASA Astrophysics Data System (ADS)

    Ezquerra Riega, Sergio D.; Rodríguez, Hernán B.; San Román, Enrique

    2017-03-01

    The effect of dye concentration on the fluorescence,ΦF, and singlet molecular oxygen,ΦΔ, quantum yields of rose bengal loaded poly(2-hydroxyethyl methacrylate) thin films (∼200 nm thick) was investigated, with the aim of understanding the effect of molecular interactions on the photophysical properties of dyes in crowded constrained environments. Films were characterized by absorption and fluorescence spectroscopy, singlet molecular oxygen (1O2) production was quantified using a chemical monitor, and the triplet decay was determined by laser flash-photolysis. For the monomeric dilute dye, ΦF = 0.05 ± 0.01 and ΦΔ = 0.76 ± 0.14. The effect of humidity and the photostability of the dye were also investigated. Spectral changes in absorption and fluorescence in excess of 0.05 M and concentration self-quenching after 0.01 M are interpreted in the context of a quenching radius model. Calculations of energy migration and trapping rates were performed assuming random distribution of the dye. Best fits of fluorescence quantum yields with concentration are obtained in the whole concentration range with a quenching radius r Q = 1.5 nm, in the order of molecular dimensions. Agreement is obtained only if dimeric traps are considered photoactive, with an observed fluorescence quantum yield ratio ΦF,trap/ΦF,monomer ≈ 0.35. Fluorescent traps are capable of yielding triplet states and 1O2. Results show that the excited state generation efficiency, calculated as the product between the absorption factor and the fluorescence quantum yield, is maximized at around 0.15 M, a very high concentration for random dye distributions. Relevant information for the design of photoactive dyed coatings is provided.

  4. Sonodynamic inactivation of Gram-positive and Gram-negative bacteria using a Rose Bengal-antimicrobial peptide conjugate.

    PubMed

    Costley, David; Nesbitt, Heather; Ternan, Nigel; Dooley, James; Huang, Ying-Ying; Hamblin, Michael R; McHale, Anthony P; Callan, John F

    2017-01-01

    Combating antimicrobial resistance is one of the most serious public health challenges facing society today. The development of new antibiotics or alternative techniques that can help combat antimicrobial resistance is being prioritised by many governments and stakeholders across the globe. Antimicrobial photodynamic therapy is one such technique that has received considerable attention but is limited by the inability of light to penetrate through human tissue, reducing its effectiveness when used to treat deep-seated infections. The related technique sonodynamic therapy (SDT) has the potential to overcome this limitation given the ability of low-intensity ultrasound to penetrate human tissue. In this study, a Rose Bengal-antimicrobial peptide conjugate was prepared for use in antimicrobial SDT (ASDT). When Staphylococcus aureus and Pseudomonas aeruginosa planktonic cultures were treated with the conjugate and subsequently exposed to ultrasound, 5 log and 7 log reductions, respectively, in bacterial numbers were observed. The conjugate also displayed improved uptake by bacterial cells compared with a mammalian cell line (P ≤ 0.01), whilst pre-treatment of a P. aeruginosa biofilm with ultrasound resulted in a 2.6-fold improvement in sensitiser diffusion (P ≤ 0.01). A preliminary in vivo experiment involving ASDT treatment of P. aeruginosa-infected wounds in mice demonstrated that ultrasound irradiation of conjugate-treated wounds affects a substantial reduction in bacterial burden. Combined, the results obtained from this study highlight ASDT as a targeted broad-spectrum novel modality with potential for the treatment of deep-seated bacterial infections. Copyright © 2016. Published by Elsevier B.V.

  5. Facile fabrication of CuO-Pb2O3 nanophotocatalyst for efficient degradation of Rose Bengal dye under visible light irradiation

    NASA Astrophysics Data System (ADS)

    Kamaraj, Eswaran; Somasundaram, Sivaraman; Balasubramani, Kavitha; Eswaran, Muthu Prema; Muthuramalingam, Rajarajan; Park, Sanghyuk

    2018-03-01

    A p-type CuO/n-type Pb2O3 heterojunction photocatalyst was prepared by a simple wet chemical process and the photocatalytic ability was evaluated for the degradation of Rose Bengal (RB) under visible light irradiation. Synthesized nanocatalysts were characterized by X-ray diffraction (XRD), UV-vis diffuse reflectance spectroscopy (DRS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Energy-dispersive X-ray spectroscopy (EDS), Brunauer-Emmett-Teller (BET) surface area analysis, and X-ray photoelectron spectroscopy (XPS). The p-n heterojunction of CuO-Pb2O3 nanostructures can promote the light absorption capability of photocatalyst and charge separation of electron-hole pairs. Photodegradation assays showed that the addition of CuO effectively enhanced the photocatalytic activity of CuO-Pb2O3 under visible light irradiation (λmax > 420 nm). Compared with pure Pb2O3 and CuO, the CuO-Pb2O3 exhibited significantly enhanced photocatalytic degradation activity. The reaction rate constant of CuO-Pb2O3 is 0.092 min-1, which is much higher than those of CuO (0.073 min-1) and Pb2O3 (0.045 min-1).

  6. Reevaluation of analytical methods for photogenerated singlet oxygen

    PubMed Central

    Nakamura, Keisuke; Ishiyama, Kirika; Ikai, Hiroyo; Kanno, Taro; Sasaki, Keiichi; Niwano, Yoshimi; Kohno, Masahiro

    2011-01-01

    The aim of the present study is to compare different analytical methods for singlet oxygen and to discuss an appropriate way to evaluate the yield of singlet oxygen photogenerated from photosensitizers. Singlet oxygen photogenerated from rose bengal was evaluated by electron spin resonance analysis using sterically hindered amines, spectrophotometric analysis of 1,3-diphenylisobenzofuran oxidation, and analysis of fluorescent probe (Singlet Oxygen Sensor Green®). All of the analytical methods could evaluate the relative yield of singlet oxygen. The sensitivity of the analytical methods was 1,3-diphenylisobenzofuran < electron spin resonance < Singlet Oxygen Sensor Green®. However, Singlet Oxygen Sensor Green® could be used only when the concentration of rose bengal was very low (<1 µM). In addition, since the absorption spectra of 1,3-diphenylisobenzofuran is considerably changed by irradiation of 405 nm laser, photosensitizers which are excited by light with a wavelength of around 400 nm such as hematoporphyrin cannot be used in the 1,3-diphenylisobenzofuran oxidation method. On the other hand, electron spin resonance analysis using a sterically hindered amine, especially 2,2,6,6-tetramethyl-4-piperidinol and 2,2,5,5-tetramethyl-3-pyrroline-3-carboxamide, had proper sensitivity and wide detectable range for the yield of photogenerated singlet oxygen. Therefore, in photodynamic therapy, it is suggested that the relative yield of singlet oxygen generated by various photosensitizers can be evaluated properly by electron spin resonance analysis. PMID:21980223

  7. Photodegradation of environmental mutagens by visible irradiation in the presence of xanthene dyes as photosensitizers.

    PubMed

    Odo, Junichi; Torimoto, Sei-ichi; Nakanishi, Suguru; Niitani, Tomoya; Aoki, Hiroyuki; Inoguchi, Masahiko; Yamasaki, Yu

    2012-01-01

    The photodegradation of environmental mutagens, such as 3-amino-1,4-dimethyl-5H-pyrido[4,3-b]indole (Trp-P-1), 3-amino-1-methyl-5H-pyrido[4,3-b]indole (Trp-P-2), 2-amino-3-methyl-9H-pyrido[2,3-b]indole (MeAαC), and 2-amino-3-methyl-imidazo[4,5-f]quinoline (IQ), was investigated by visible irradiation in the presence of xanthene dyes as photosensitizers. Although the environmental mutagens themselves were very stable during visible irradiation under the conditions in this study, they were effectively photodegraded in the presence of the xanthene dyes (erythrosine, rose bengal, and phloxine). Moreover, photodegradation of the mutagens was further enhanced for xanthene dyes loaded onto a water-soluble diethylaminoethyl (DEAE)-dextran anion-exchanger via ionic interactions (xanthene-dyeDEX). Photodegradation was inhibited by O2 removal from the reaction solution. In ESR spin-trapping experiments using 5,5-dimethyl-1-pyrroline-N-oxide (DMPO) as a trapping reagent, signals characteristic of DMPO-•OH (hydroxyl radical) were observed in the presence of xanthene-dyeDEX. These results suggest that reactive oxygen species derived from O2, such as singlet molecular oxygen (•1O2) and/or •OH, were active participants in photodegradation of the mutagens in the presence of xanthene dyes or xanthene-dyeDEX.

  8. Reduced graphene oxide-rose bengal hybrid film for improved ammonia detection with low humidity interference at room temperature

    NASA Astrophysics Data System (ADS)

    Midya, Anupam; Ghosh, Ruma; Santra, Sumita; Ray, Samit K.; Guha, Prasanta K.

    2016-02-01

    Development of chemoresistive ammonia sensor that does not suffer with humidity interference is highly desirable for practical environmental monitoring systems. We report enhanced ammonia sensing using chemically reduced graphene oxide (RGO) and rose bengal (RB) nanocomposite fabricated in a very simple and cost effective manner. The RGO-RB nanocomposites were synthesized using three different concentrations (2 mg mL-1, 5 mg mL-1 and 10 mg mL-1) of RB keeping the RGO concentration same. Ammonia and humidity sensing of these three different composites were explored. Interestingly, it was observed that with increasing concentration of RB, the sensitivity of the sensor towards ammonia was increased but the sensitivity towards humidity was decreased. The response of the nanocomposites varied from ˜9-45% against 400-2800 ppm of ammonia whereas intrinsic RGO showed a response of merely 17% against 2800 ppm of ammonia. On the other hand the response of the nanocomposite based sensor was reduced from 18% to 7% against 100% relative humidity. Also, the sensor was found to be selective towards ammonia when tested against other toxic volatile organic compounds. The limit of detection of the RGO-RB based sensor was calculated to be as low as 0.9 ppm. Field emission scanning electron microscopy, transmission electron microscopy, Raman spectroscopy, Fourier transform infrared spectroscopy and UV-vis spectroscopy were carried out for the detailed structural characterizations of the sensing layer. These results are believed to be very useful for the cost effective fabrication of graphene based ammonia sensors which have reduced effects of humidity.

  9. Cationic, anionic and neutral dyes: effects of photosensitizing properties and experimental conditions on the photodynamic inactivation of pathogenic bacteria.

    PubMed

    Sabbahi, Sonia; Ben Ayed, Layla; Boudabbous, Abdellatif

    2013-12-01

    The aim of this study was to evaluate the photobactericidal effect of four photosensitizers (PSs) with different structural and physico-photochemical properties, namely mesotetracationic porphyrin (T4MPyP), dianionic rose Bengal (RB), monocationic methylene blue (MB) and neutral red (NR). Their photokilling activity was tested in vitro on pathogenic bacteria such as Pseudomonas aeruginosa (P. aeruginosa) and Staphylococcus aureus (S. aureus) suspended in nutrient broth (NB) and in phosphate buffered saline (PBS) through following their influence on the PSs antimicrobial efficacy. Photodynamic inactivation (PDI) experiments were performed using visible light (L) and different PSs concentrations (20-70 μM). The ability of these PSs to mediate bacterial photodynamic inactivation was investigated as a function of type of PS and its concentrations, spectral and physico-chemical properties, bacterial strain, irradiation time and suspending medium. Indeed, they showed antibacterial effects against S. aureus and P. aeruginosa with significant difference in potency. Staphylococcus aureus suspended in NB showed 0.92 log units reduction in viable count in the presence of T4MPyP at 20 μM. Changing the suspending medium from NB to PBS, S. aureus was successfully photoinactivated by T4MPyP (20 μM) when suspended in PBS at least time exposure (10 and 30 min), followed by MB and RB.

  10. Serological profile of buffalo (Bubalus bubalis) female calves vaccinated with standard Brucella abortus strain 19 vaccine using rose bengal, 2-mercaptoethanol and complement fixation tests.

    PubMed

    Nardi, G Júnior; Ribeiro, M G; Jorge, A M; Megid, J; Silva, L M P

    2012-03-01

    The serological profiles of 21 female buffaloes vaccinated between 3 and 8 months of age using Brucella abortus strain 19 (S19) were evaluated by rose bengal (RBT), 2-mercaptoethanol (2ME) and complement fixation (CFT) tests. The serum strains were collected in day zero, 15, 30, 45, 60th days and subsequently to each 30 months, until 720th day after vaccination. No animal showed reaction in day zero. In 15th day above 95% of animals revealed reaction in all tests. All the animals presented absence of reactions in CFT, RBT and 2ME tests at 270, 300 and 360 days after vaccination, respectively. Our finding highlighted early response in CFT compared than other conventional agglutination tests. None of animals presented oscillation of titers or reactions in any test after 360 day of study, which enables the use of these tests after this period without interference of antibodies from S19 vaccine origin between 3 and 8 months in buffalo heifers. Copyright © 2011 The International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  11. Live foraminiferal faunas (Rose Bengal stained) from the northern Arabian Sea: links with bottom-water oxygenation

    NASA Astrophysics Data System (ADS)

    Caulle, C.; Koho, K. A.; Mojtahid, M.; Reichart, G. J.; Jorissen, F. J.

    2013-09-01

    Live (Rose Bengal stained) benthic foraminifera from the Murray Ridge, within and below the northern Arabian Sea Oxygen Minimum Zone (OMZ), were studied in order to determine the relationship between faunal composition, bottom-water oxygenation (BWO), pore-water chemistry and organic matter (organic carbon and phytopigment) distribution. A series of multicores were recovered from a ten-station oxygen (BWO: 2-78 μM) and bathymetric (885-3010 m depth) transect during the winter monsoon in January 2009. Foraminifera were investigated from three different size fractions (63-125 μm, 125-150 μm and > 150 μm). The larger foraminifera (> 125 μm) were strongly dominated by agglutinated species (e.g. Reophax spp.). In contrast, in the 63-125 μm fraction, calcareous taxa were more abundant, especially in the core of the OMZ, suggesting an opportunistic behaviour. On the basis of a Principal Component Analysis, three foraminiferal groups were identified, reflecting the environmental parameters along the study transect. The faunas from the shallowest stations, in the core of the OMZ (BWO: 2 μM), were composed of "low oxygen" species, typical of the Arabian Sea OMZ (e.g., Rotaliatinopsis semiinvoluta, Praeglobobulimina spp. , Bulimina exilis, Uvigerina peregrina typeparva). These taxa are adapted to the very low BWO conditions and to high phytodetritus supplies. The transitional group, typical for the lower part of the OMZ (BWO: 5-16 μM), is composed of more cosmopolitan taxa tolerant to low-oxygen concentrations (Globocassidulina subglobosa, Ehrenbergina trigona). Below the OMZ (BWO: 26-78 μM), where food availability is more limited and becomes increasingly restricted to surficial sediments, more cosmopolitan calcareous taxa were present, such as Bulimina aculeata, Melonis barleeanus, Uvigerina peregrina and Epistominella exigua. Miliolids were uniquely observed in this last group, reflecting the higher BWO. At these deeper sites, the faunas exhibit a clear depth

  12. A compact fiber-optic probe-based singlet oxygen luminescence detection system.

    PubMed

    Gemmell, Nathan R; McCarthy, Aongus; Kim, Michele M; Veilleux, Israel; Zhu, Timothy C; Buller, Gerald S; Wilson, Brian C; Hadfield, Robert H

    2017-02-01

    This paper presents a novel compact fiberoptic based singlet oxygen near-infrared luminescence probe coupled to an InGaAs/InP single photon avalanche diode (SPAD) detector. Patterned time gating of the single-photon detector is used to limit unwanted dark counts and eliminate the strong photosensitizer luminescence background. Singlet oxygen luminescence detection at 1270 nm is confirmed through spectral filtering and lifetime fitting for Rose Bengal in water, and Photofrin in methanol as model photosensitizers. The overall performance, measured by the signal-to-noise ratio, improves by a factor of 50 over a previous system that used a fiberoptic-coupled superconducting nanowire single-photon detector. The effect of adding light scattering to the photosensitizer is also examined as a first step towards applications in tissue in vivo. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Influence of dynamic contact of hard contact lens materials on corneal epithelial cells examined by rose bengal staining.

    PubMed

    Iguchi, I; Kamiyama, K; Imamichi, M; Ohashi, T; He, J; Wang, X; Imanishi, J

    1996-06-01

    To establish a method for evaluation of less irritating contact lens materials by dynamic contact with cornea, we examined epithelial and endothelial cell injury to the porcine cornea caused by rotatory rubbing with four kinds of hard contact lenses (HCL). The HCLs used were (1) polymethylmethacrylate (PMMA) HCL, (2) gas-permeable HCL composed of a graft co-polymer of dextran derivative and methylmethacrylate (MMA) (Suncon Mild II(TM), 12 Dk), (3) gas-permeable HCL composed of a graft co-polymer of dextran derivative, a monomer containing silicone, a monomer containing fluorine and MMA (New Dx HCL-136, 32 Dk), and (4) gas-permeable HCL composed of a monomer containing silicone, a monomer containing fluorine and MMA(RGPL-A, 216 Dk). Using a specially designed apparatus, we produced a standardized injury to the epithelium or endothelium of porcine corneas by holding the HCL against the corneal surface while rotating the lens rapidly. After rotatory rubbing of the HCL on the epithelium, the degree of rose bengal staining of the epithelial cells, indicating degeneration of the cells and mucin detachment, were significantly different among these HCLs (New Dx HCL-136 < Suncon Mild II(TM), PPMA < RGPL-A), and the cell injury rates of the endothelium were also significantly different among them (Suncon Mild II(TM) < New Dx HCL-136, PMMA < RGPL-A). The water-wettability of HCLs was not directly correlated with cell injury rates on epithelial and endothelial cells. Both the New Dx HCL-136 and Suncon Mild II(TM), which have a common composition of graft co-polymer of dextran derivative, are less irritating to the epithelium and to the endothelium. Also a very few patients complaints regarding Suncon Mild II(TM) wearing in individuals with dry eyes have been reported. Therefore, we would expect that the New Dx HCL-136 should be satisfactory for wear by individuals with dry eyes.

  14. Live (Rose Bengal stained) foraminiferal faunas from the northern Arabian Sea: faunal succession within and below the OMZ

    NASA Astrophysics Data System (ADS)

    Caulle, Clemence; Koho, Karoliina; Mojtahid, Meryem; Reichart, Gert-Jan; Jorissen, Frans

    2014-05-01

    Live (Rose Bengal stained) benthic foraminifera from the Murray Ridge, within and below the northern Arabian Sea Oxygen Minimum Zone (OMZ), were studied in order to determine the relationship between faunal composition, bottom-water oxygenation (BWO), pore-water chemistry and organic matter (organic carbon and phytopigment) distribution. A series of multicores were recovered from a ten-station oxygen (BWO: 2µM - 78µM) and bathymetric (885 - 3010m depth) transect during the winter monsoon in January 2009. Foraminifera were investigated from three different size fractions (63-125µm, 125-150µm and >150µm). The larger foraminifera (>125µm) were strongly dominated by agglutinated species (e.g. Reophax spp.). In contrast, in the 63-125µm fraction, calcareous taxa were more abundant, especially in the core of the OMZ. On the basis of a Principal Components Analysis, three foraminiferal groups were identified and correlated to the environmental parameters by Canonical Correspondence Analysis. The faunas from the shallowest stations, in the core of the OMZ (BWO: 2µM), were composed of "low oxygen" species, typical of the Arabian Sea OMZ (e.g., Rotaliatinopsis semiinvoluta, Praeglobobulimina sp., Bulimina exilis, Uvigerina peregrina type parva). These taxa are adapted to the very low BWO conditions and to high phytodetritus supplies. The transitional group, typical for the lower part of the OMZ (BWO: 5-16µM), is composed of species, which are tolerant as well to low-oxygen concentrations, but may be less critical with respect to organic supplies (e.g. Globocassidulina subglobosa, Ehrenbergina trigona). Below the OMZ (BWO: 26-78µM), where food availability is more limited and becomes increasingly restricted to surficial sediments, cosmopolitan calcareous taxa were present, such as Bulimina aculeata, Melonis barleeanus, Uvigerina peregrina and Epistominella exigua. Miliolids were uniquely observed in this last zone, reflecting the higher BWO and/or lower organic

  15. Time-resolved singlet-oxygen luminescence detection with an efficient and practical semiconductor single-photon detector

    PubMed Central

    Boso, Gianluca; Ke, Damei; Korzh, Boris; Bouilloux, Jordan; Lange, Norbert; Zbinden, Hugo

    2015-01-01

    In clinical applications, such as PhotoDynamic Therapy, direct singlet-oxygen detection through its luminescence in the near-infrared range (1270 nm) has been a challenging task due to its low emission probability and the lack of suitable single-photon detectors. Here, we propose a practical setup based on a negative-feedback avalanche diode detector that is a viable alternative to the current state-of-the art for different clinical scenarios, especially where geometric collection efficiency is limited (e.g. fiber-based systems, confocal microscopy, scanning systems etc.). The proposed setup is characterized with Rose Bengal as a standard photosensitizer and it is used to measure the singlet-oxygen quantum yield of a new set of photosensitizers for site-selective photodynamic therapy. PMID:26819830

  16. Living (Rose Bengal stained) benthic foraminiferal faunas along a strong bottom-water oxygen gradient on the Indian margin (Arabian Sea)

    NASA Astrophysics Data System (ADS)

    Caulle, C.; Mojtahid, M.; Gooday, A. J.; Jorissen, F. J.; Kitazato, H.

    2015-02-01

    Rose Bengal stained foraminiferal assemblages were analysed along a five-station bathymetric transect across the core and the lower part of the oxygen minimum zone (OMZ) on the Indian margin of the Arabian Sea. Sediment cores were collected using the manned submersible Shinkai 6500 during RV Yokosuka cruise YK08-11 in the post-monsoon season (October 2008) at water depths ranging from 535 to 2000 m, along a gradient from almost anoxic to well-oxygenated (0.3 to 108 μM) bottom waters. Stained foraminiferal densities were very high in the OMZ core (535 m) and decreased with depth. The faunas were dominated (40-80%) by non-calcareous taxa at all stations. These were mainly species of Reophax and Lagenammina but also included delicate monothalamous taxa (organic-walled "allogromiids", agglutinated saccamminids, psammosphaerids and tubular forms). These new data from the Indian margin are compared to previous studies from the Murray Ridge, the Pakistan margin and the Oman margin. The fact that similar species were found at sites with comparable bottom-water oxygen concentrations but with very different surface water productivity suggests that, within the strongly developed Arabian Sea OMZ, bottom-water oxygen concentration, and not the organic flux to the sea floor, is the main factor controlling the species composition of the foraminiferal communities. Several foraminiferal species (e.g. Praeglobobulimina sp. 1, Ammodiscus sp. 1, Bolivina aff. dilatata) were confined to the core of the OMZ and are presently known only from the Arabian Sea. Because of their association with extremely low-oxygen concentration, these species may prove to be good indicators of past OMZ variability in the Arabian Sea.

  17. Live (Rose Bengal stained) foraminiferal faunas from the northern Arabian Sea: faunal succession within and below the OMZ

    NASA Astrophysics Data System (ADS)

    Caulle, C.; Koho, K. A.; Mojtahid, M.; Reichart, G. J.; Jorissen, F. J.

    2014-02-01

    Live (Rose Bengal stained) benthic foraminifera from the Murray Ridge, within and below the northern Arabian Sea oxygen minimum zone (OMZ), were studied in order to determine the relationship between faunal composition, bottom water oxygenation (BWO), pore water chemistry and organic matter (organic carbon and phytopigment) distribution. A series of multicores were recovered from a ten-station oxygen (BWO: 2-78 μM) and bathymetric (885-3010 m depth) transect during the winter monsoon in January 2009. Foraminifera were investigated from three different size fractions (63-125 μm, 125-150 μm and >150 μm). The larger foraminifera (>125 μm) were strongly dominated by agglutinated species (e.g. Reophax spp.). In contrast, in the 63-125 μm fraction, calcareous taxa were more abundant, especially in the core of the OMZ. On the basis of a principal components analysis, three foraminiferal groups were identified and correlated to the environmental parameters by canonical correspondence analysis. The faunas from the shallowest stations, in the core of the OMZ (BWO: 2 μM), were composed of "low oxygen" species, typical of the Arabian Sea OMZ (e.g. Rotaliatinopsis semiinvoluta, Praeglobobulimina sp., Bulimina exilis, Uvigerina peregrina type parva). These taxa are adapted to the very low BWO conditions and to high phytodetritus supplies. The transitional group, typical for the lower part of the OMZ (BWO: 5-16 μM), is composed of species that are tolerant as well to low-oxygen concentrations, but may be less critical with respect to organic supplies (e.g. Globocassidulina subglobosa, Ehrenbergina trigona). Below the OMZ (BWO: 26-78 μM), where food availability is more limited and becomes increasingly restricted to surficial sediments, cosmopolitan calcareous taxa were present, such as Bulimina aculeata, Melonis barleeanus, Uvigerina peregrina and Epistominella exigua. Miliolids were uniquely observed in this last zone, reflecting the higher BWO and/or lower organic

  18. Living (Rose-Bengal-stained) benthic foraminiferal faunas along a strong bottom-water oxygen gradient on the Indian margin (Arabian Sea)

    NASA Astrophysics Data System (ADS)

    Caulle, C.; Mojtahid, M.; Gooday, A. J.; Jorissen, F. J.; Kitazato, H.

    2015-08-01

    Rose-Bengal-stained foraminiferal assemblages (> 150 μm) were analysed along a five-station bathymetric transect across the core and the lower part of the oxygen minimum zone (OMZ) on the Indian margin of the Arabian Sea. Sediment cores were collected using the manned submersible Shinkai 6500 during the RV Yokosuka cruise YK08-11 in the post-monsoon season (October 2008) at water depths ranging from 535 to 2000 m, along a gradient from almost anoxic to well-oxygenated (0.3 to 108 μM) bottom waters. Stained benthic foraminifera were investigated from two different size fractions (150-300 μm and > 300 μm). Stained foraminiferal densities were very high in the core of the OMZ (at 535 and 649 m) and decreased at deeper sites. The faunas (> 150 μm) were dominated (40-80 %) by non-calcareous taxa at all stations. These were mainly species of Reophax and Lagenammina but also included delicate monothalamous taxa (organic-walled "allogromiids", agglutinated saccamminids, psammosphaerids and tubular forms). These new data from the Indian margin are compared to previous studies from the Murray Ridge, the Pakistan margin and the Oman margin. The fact that similar species were found at sites with comparable bottom-water oxygen concentrations but with very different surface water productivity suggests that, within the strongly developed Arabian Sea OMZ, bottom-water oxygen concentration, and not the organic flux to the sea floor, is the main factor controlling the species composition of the foraminiferal communities. Several foraminiferal species (e.g. Praeglobobulimina sp. 1, Ammodiscus sp. 1, Bolivina aff. dilatata) were confined to the core of the OMZ. These species are presently known only from the Arabian Sea. Because of their association with extremely low oxygen concentrations, these species may be good markers for very low oxygen concentrations, and could be used to reconstruct past OMZ variability in the Arabian Sea.

  19. How do you get the Rose Bengal Test at the point-of-care to diagnose brucellosis in Africa? The importance of a systems approach.

    PubMed

    Ducrotoy, Marie J; Bardosh, Kevin L

    2017-01-01

    Brucellosis is a major neglected zoonotic disease, whose burden both in animals and humans is severely under-reported. Diagnosis in humans identifies cases in order to treat the disease at the individual level. In animals diagnosis is implemented at the population level in the context of appropriate control or eradication strategies. Molecular and bacteriological diagnosis are rarely undertaken in sub-Saharan Africa, at least outside research projects, due to cost, skills and laboratory infrastructure issues. The brucellosis toolbox contains a wide range of serological tests, but the perfect test for use in animals and humans respectively does not exist. Drug and diagnostic discovery for the neglected zoonoses are notoriously poor, and there is limited investment interest in developing new tools for brucellosis diagnosis. But are current tools being used to their full capacity? The rose Bengal test (RBT) stands out as an efficient, practical and very cheap test adapted for use in the resource-poor context. In this paper, we argue that a social science or system's approach to explore the practicality of improving diagnostic capacity at the point-of care in high-risk brucellosis areas of rural Africa may be a step towards solving the issue of under-diagnosis, but this must go hand-in-hand with implementation of control measures at source in the animal reservoir and capacity to treat human cases. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Duration of skin photosensitivity and incidence of photosensitivity reactions after administration of verteporfin.

    PubMed

    Houle, Jean-Marie; Strong, H Andrew

    2002-12-01

    Verteporfin (Visudyne, Novartis AG) is a light-activated drug that reduces the risk of vision loss in patients with certain types of choroidal neovascularization (CNV). Because photosensitivity can occur with photosensitizers, it is important for ophthalmologists providing verteporfin therapy to understand its time course and duration, as well as the incidence of photosensitivity reactions. Data were obtained from three sources: 1) the time course of skin photosensitivity in 17 volunteers by measuring erythema/edema over time after verteporfin, using red light exposure; 2) the duration of skin photosensitivity in 30 patients with skin cancer by exposing skin to simulated solar light and calculating the daily minimal erythematous dose; and 3) the incidences of photosensitivity reactions as recorded in three phase III trials in patients with CNV secondary to age-related macular degeneration or pathologic myopia who received the regimen of verteporfin therapy currently approved by regulatory authorities (infusion of 6 mg/m(2) body surface area). 1) Skin photosensitivity was high at the first timepoint of 1.5 hours after dosing and decreased rapidly thereafter; 2) the duration of skin photosensitivity was dose dependent, ranging from 2.0 to 6.7 days at 6 to 20 mg/m(2), respectively (mean of 2 days at a dose of 6 mg/m(2)); and 3) photosensitivity reactions occurred in only 2.2% of patients in the phase III trials, including two severe events, one secondary to extravasation. All treatment-related reactions in the phase III trials occurred within the first 2 days after dosing, with the exception of two mild reactions and one moderate reaction that occurred 3 days after treatment. Verteporfin is associated with short-lived photosensitivity and a low incidence of photosensitivity reactions in clinical trials, most of which could probably have been avoided by adherence to protocol instructions for skin protection.

  1. Photodynamic antimicrobial therapy to inhibit pseudomonas aeruginosa of corneal isolates (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Durkee, Heather A.; Relhan, Nidhi; Arboleda, Alejandro; Halili, Francisco; De Freitas, Carolina; Alawa, Karam; Aguilar, Mariela C.; Amescua, Guillermo; Miller, Darlene; Parel, Jean-Marie

    2016-03-01

    Keratitis associated with Pseudomonas aeruginosa is difficult to manage. Treatment includes antibiotic eye drops, however, some strains of Pseudomonas aeruginosa are resistant. Current research efforts are focused on finding alternative and adjunct therapies to treat multi-drug resistant bacteria. One promising alternate technique is photodynamic therapy (PDT). The purpose of this study was to evaluate the effect of riboflavin- and rose bengal-mediated PDT on Pseudomonas aeruginosa keratitis isolates in vitro. Two isolates (S+U- and S-U+) of Pseudomonas aeruginosa were derived from keratitis patients and exposed to five experimental groups: (1) Control (dark, UV-A irradiation, 525nm irradiation); (2) 0.1% riboflavin (dark, UV-A irradiation); and (3) 0.1% rose bengal, (4) 0.05% rose bengal and (5) 0.01% rose bengal (dark, 525nm irradiation). Three days after treatment, in dark conditions of all concentration of riboflavin and rose bengal showed no inhibition in both S+U- and S-U+ strains of Pseudomonas aeruginosa. In 0.1% and 0.05% rose bengal irradiated groups, for both S+U- and S-U+ strains, there was complete inhibition of bacterial growth in the central 50mm zone corresponding to the diameter of the green light source. These in vitro results suggest that rose bengal photodynamic therapy may be an effective adjunct treatment for Pseudomonas aeruginosa keratitis.

  2. Study of photosensitization reaction progress in a 96 well plate with photosensitizer rich condition using Talaporfin sodium

    NASA Astrophysics Data System (ADS)

    Ogawa, Emiyu; Takahashi, Mei; Arai, Tsunenori

    2013-02-01

    To quantitatively investigate photosensitization reaction in vitro against myocardial cells with photosensitizer rich condition in solution using Talaporfin sodium in the well of a 96 well plate, we studied photosensitization reaction progress in this well. We have proposed non-thermal conduction block of myocardium tissue using the photosensitization reaction with laser irradiation shortly after Talaporfin sodium injection. In above situation, the photosensitizer is located outside the myocardial cells in high concentration. To understand interaction of the photosensitization reaction in which the photosensitizer distributes outside cells, the photosensitization reaction progress in the well was studied. Talaporfin sodium (799.69 MW) solution and a 663 nm diode laser were used. The photosensitizer solution concentrations of 12.5-37.5 μM were employed. The photosensitizer fluorescence with 0.29 W/cm2 in irradiance, which was optimized in previous cell death study, was measured during the laser irradiation until 40 J/cm2. The photosensitizer solution absorbance and dissolved oxygen pressure after the laser irradiation were also measured. We found that the photosensitization reaction progress had 2 distinctive phases of different reaction rate: rapid photosensitization reaction consuming dissolved oxygen and gentle photosensitization reaction with oxygen diffusion from the solution-air boundary. The dissolved oxygen pressure and photosensitizer solution absorbance were 30% and 80% of the initial values after the laser irradiation, respectively. Therefore, oxygen was rate-controlling factor of the photosensitization reaction in the well with the photosensitizer rich condition. In the oxygen diffusion phase, the oxygen pressure was maintained around 40 mmHg until the laser irradiation of 40 J/cm2 and it is similar to that of myocardium tissue in vivo. We think that our 96 well plate in vitro system may simulate PDT in myocardial tissue with photosensitization reaction

  3. Living (Rose-Bengal-Stained) benthic foraminifera along the Kveithola Trough (NW Barents Sea), environmental implications

    NASA Astrophysics Data System (ADS)

    Sabbatini, Anna; Morigi, Caterina; Lucchi, Renata G.; de Vittor, Cinzia; Bazzano, Matteo

    2017-04-01

    The distribution and composition of benthic foraminiferal fauna in the Kveithola Trough (NW Barents Sea) were studied in three depositional settings identified on the basis of surface depositional structures, sediment types and present ecosystem characteristics. Sediment samples were collected during the CORIBAR cruise (Hanebuth et al., 2013) aimed at drilling glacigenic sediments in a palaeo-ice stream depositional system in the western Barents Sea. In particular, we report the quantitative data of the living benthic foraminiferal density, biodiversity and vertical distribution in three box-core sediment samples (0-10 cm) collected in two inner trough sites, the drift area and the channel/fault area and one outer shelf site. Rose-Bengal-stained foraminiferal assemblages were investigated from two different size fractions (63-150 and >150 micrometres). In the drift area, the living benthic foraminiferal assemblage is characterized by the presence of oxygen-depleted environmental taxa with low foraminiferal density and biodiversity. This area appears a stagnant environment, strongly affected by low-oxygen, stressed environmental conditions in which foraminifera developed a life strategy aimed to increase the efficiency of food utilization and maximum resistance to ecological stress. As a further support to this interpretation, all the sediments recovered in the drift area are rich in organic matter and in Siboglinid-like tubes together with pockmark evidences on the surface of the box-corer. The sedimentation in the channel/fault area is very similar to that described for the drift area, evidencing stressed environmental conditions. Opportunistic species dominate the benthic foraminiferal fauna. The species distribution of the internal trough sites is consistent with the lithology and with data of quantity and biochemical composition (in terms of phytopigment, protein, lipid, carbohydrate and biopolymeric carbon) of the organic matter. Values of biopolymeric carbon

  4. Effects of edaravone, a free radical scavenger, on photochemically induced cerebral infarction in a rat hemiplegic model.

    PubMed

    Ikeda, Satoshi; Harada, Katsuhiro; Ohwatashi, Akihiko; Kamikawa, Yurie

    2013-01-01

    Edaravone is a free radical scavenger that protects the adjacent cortex during cerebral infarction. We created a hemiparetic model of cerebral thrombosis from a photochemically induced infarction with the photosensitive dye, rose bengal, in rats. We examined the effects of edaravone on recovery in the model. A total of 36 adult Wistar rats were used. The right sensorimotor area was irradiated with green light with a wavelength of 533 nm (10 mm diameter), and the rose bengal was injected intravenously to create an infarction. The edaravone group was injected intraperitoneally with edaravone (3 mg/kg), and the control group was injected with saline. The recovery process of the hemiplegia was evaluated with the 7-step scale of Fenny. The infarcted areas were measured after fixation. The recovery of the paralysis in the edaravone-treated group was significantly earlier than that in the untreated group. Seven days later, both groups were mostly recovered and had scores of 7, and the infarction region was significantly smaller in the edaravone-treated group. Edaravone reduced the infarction area and promoted the functional recovery of hemiparesis from cerebral thrombosis in a rat model. These findings suggest that edaravone treatment would be effective in clinical patients recovering from cerebral infarction.

  5. Effects of Edaravone, a Free Radical Scavenger, on Photochemically Induced Cerebral Infarction in a Rat Hemiplegic Model

    PubMed Central

    Harada, Katsuhiro; Ohwatashi, Akihiko; Kamikawa, Yurie

    2013-01-01

    Edaravone is a free radical scavenger that protects the adjacent cortex during cerebral infarction. We created a hemiparetic model of cerebral thrombosis from a photochemically induced infarction with the photosensitive dye, rose bengal, in rats. We examined the effects of edaravone on recovery in the model. A total of 36 adult Wistar rats were used. The right sensorimotor area was irradiated with green light with a wavelength of 533 nm (10 mm diameter), and the rose bengal was injected intravenously to create an infarction. The edaravone group was injected intraperitoneally with edaravone (3 mg/kg), and the control group was injected with saline. The recovery process of the hemiplegia was evaluated with the 7-step scale of Fenny. The infarcted areas were measured after fixation. The recovery of the paralysis in the edaravone-treated group was significantly earlier than that in the untreated group. Seven days later, both groups were mostly recovered and had scores of 7, and the infarction region was significantly smaller in the edaravone-treated group. Edaravone reduced the infarction area and promoted the functional recovery of hemiparesis from cerebral thrombosis in a rat model. These findings suggest that edaravone treatment would be effective in clinical patients recovering from cerebral infarction. PMID:23853531

  6. Photosensitive disorders in HIV

    PubMed Central

    2017-01-01

    Photosensitive disorders are common, affecting up to 5% of HIV-positive patients. HIV itself induces photosensitivity but photoaggravated drug reactions, porphyria cutanea tarda and nutritional disorders such as pellagra are also more common in patients with HIV. In South Africa, actinic lichenoid leukomelanoderma of HIV is a unique photosensitive disorder which is associated with advanced HIV. It is important to be able to recognise these conditions and withdraw photosensitising medications wherever possible. PMID:29568622

  7. Photosensitive disorders in HIV.

    PubMed

    Koch, Karen

    2017-01-01

    Photosensitive disorders are common, affecting up to 5% of HIV-positive patients. HIV itself induces photosensitivity but photoaggravated drug reactions, porphyria cutanea tarda and nutritional disorders such as pellagra are also more common in patients with HIV. In South Africa, actinic lichenoid leukomelanoderma of HIV is a unique photosensitive disorder which is associated with advanced HIV. It is important to be able to recognise these conditions and withdraw photosensitising medications wherever possible.

  8. Lanthanum fluoride nanoparticles for radiosensitization of tumors

    NASA Astrophysics Data System (ADS)

    Kudinov, Konstantin; Bekah, Devesh; Cooper, Daniel; Shastry, Sathvik; Hill, Colin; Bradforth, Stephen; Nadeau, Jay

    2016-03-01

    Dense inorganic nanoparticles have recently been identified as promising radiosensitizers. In addition to dose enhancement through increased attenuation of ionizing radiation relative to biological tissue, scintillating nanoparticles can transfer energy to coupled photosensitizers to amplify production of reactive oxygen species, as well as provide UVvisible emission for optical imaging. Lanthanum fluoride is a transparent material that is easily prepared as nanocrystals, and which can provide radioluminescence at a number of wavelengths through simple substitution of lanthanum ions with other luminescent lanthanides. We have prepared lanthanum fluoride nanoparticles doped with cerium, terbium, or both, that have good spectral overlap with chlorine6 or Rose Bengal photosensitizer molecules. We have also developed a strategy for stable conjugation of the photosensitizers to the nanoparticle surface, allowing for high energy transfer efficiencies on a per molecule basis. Additionally, we have succeeded in making our conjugates colloidally stable under physiological conditions. Here we present our latest results, using nanoparticles and nanoparticle-photosensitizer conjugates to demonstrate radiation dose enhancement in B16 melanoma cells. The effects of nanoparticle treatment prior to 250 kVp x-ray irradiation were investigated through clonogenic survival assays and cell cycle analysis. Using a custom apparatus, we have also observed scintillation of the nanoparticles and conjugates under the same conditions that the cell samples are irradiated.

  9. An Efficient Composition for Bengal Lights.

    ERIC Educational Resources Information Center

    Comet, M.; Schreyeck, L.; Fuzellier, H.

    2002-01-01

    Reports the discovery of an efficient base composition for making bengal lights that is obtained with potassium chlorate and thiourea. Combining this mixture with appropriate flame coloring can produce several impressive bengal lights. (DDR)

  10. Survey of six rose viruses in a rose virus collection

    USDA-ARS?s Scientific Manuscript database

    More than 25 viruses have been reported to infect roses. As part of the routine diagnostic testing at Foundation Plant Services, roses are tested for viruses by biological, serological, and molecular assays. Over the past 18 years, we identified approximately 600 roses that were worth maintaining as...

  11. Sediment dispersal pattern in the Bay of Bengal - evidence for commencement of Bengal Fan sedimentation

    NASA Astrophysics Data System (ADS)

    Krishna, K. S.; Ismaiel, M.; Karlapati, S.; Gopala Rao, D.; Mishra, J.; D, S.

    2015-12-01

    The sediment succession in the Bay of Bengal records signatures corresponding to India-Asia collision, regional climate, and erosional processes of the Himalayan orogeny and the Indian subcontinent. The Bengal Fan - world's largest submarine fan - has been long studied to understand the link between the Himalayan tectonics and Asian monsoon climate, but early phase information of the Himalaya erosion is not retrieved from the Indian Ocean due to lack of deep-core samples. Therefore, the missing corresponding signals hampered the understanding of coupled processes between tectonics, climate and erosion. Seismic reflection profiles and industrial drill wells from the western Bay of Bengal show two different modes of sediment deposition: initially Indian peninsular rivers discharged sediments to the ocean at a rate ~20 m/m.y. until Oligocene-Miocene time (~23 Ma) with the exception of two fairly-enhanced sediment pulses from 65 to 54 and again from 34 to 23 Ma; since 23 Ma the Ganges and Brahmaputra rivers added huge volumes of sediments to the bay with variable rates range from 40 to >1000 m/m.y. Using seismic stratigraphic technique we found a distinct increase in sediment discharge (~140 m/m.y.) at 23 Ma is an important age marker for the onset of Bengal Fan sedimentation as a coupled connection between the Himalayan tectonics and Asian climate. Further rise in sedimentation rate during the period 6.8 - 0.8 Ma is surprisingly not in agreement with the decrease in sediment rate reported at ODP Leg 116 sites in the distal Bengal Fan, but coincident with the change in monsoon intensity. Here we provide well constrained ages for the growth of the Bengal Fan, which can serve as benchmark for interactions between the Himalayan exhumation and Asian climate.

  12. Organic photosensitive devices

    DOEpatents

    Rand, Barry P; Forrest, Stephen R

    2013-11-26

    The present invention generally relates to organic photosensitive optoelectronic devices. More specifically, it is directed to organic photosensitive optoelectronic devices having a photoactive organic region containing encapsulated nanoparticles that exhibit plasmon resonances. An enhancement of the incident optical field is achieved via surface plasmon polariton resonances. This enhancement increases the absorption of incident light, leading to a more efficient device.

  13. γ-Fe{sub 2}O{sub 3} nanoparticles: An easily recoverable effective photo-catalyst for the degradation of rose bengal and methylene blue dyes in the waste-water treatment plant

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dutta, Amit Kumar; Maji, Swarup Kumar; Adhikary, Bibhutosh, E-mail: bibhutoshadhikary@yahoo.in

    2014-01-01

    Graphical abstract: - Highlights: • γ-Fe{sub 2}O{sub 3} NPs from a single-source precursor and characterized by XRD, TEM, UV–vis spectra. • The NPs were tested as effective photocatalyst toward degradation of RB and MB dyes. • The possible pathway of the photocatalytic decomposition process has been discussed. • The active species, OH·, was detected by TA photoluminescence probing techniques. - Abstract: γ-Fe{sub 2}O{sub 3} nanoparticles (NPs) were synthesized from a single-source precursor complex [Fe{sub 3}O(C{sub 6}H{sub 5}COO){sub 6}(H{sub 2}O){sub 3}]NO{sub 3} by a simple thermal decomposition process and have been characterized by X-ray diffraction analysis (XRD), transmission electron microscopy (TEM)more » and UV–vis spectroscopic techniques. The NPs were highly pure and well crystallized having hexagonal morphology with an average particle size of 35 nm. The prepared γ-Fe{sub 2}O{sub 3} (maghemite) NPs show effective photo-catalytic activity toward the degradation of rose bengal (RB) and methylene blue (MB) dyes under visible light irradiation and can easily be recoverable in the presence of magnetic field for successive re-uses. The possible photo-catalytic decomposition mechanism is discussed through the detection of hydroxyl radical (OH·) by terephthalic acid photo-luminescence probing technique.« less

  14. Rose Hip

    MedlinePlus

    ... with your health provider.AspirinThe body breaks down aspirin to get rid of it. Rose hip contains ... of vitamin C might decrease the breakdown of aspirin. Taking large amount of rose hip along with ...

  15. Improved photosensitizers for photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Pandey, Ravindra K.; Shiau, Fuu-Yau; Meunier, Isabelle; Ramaprasad, Subbaraya; Sumlin, Adam B.; Dougherty, Thomas J.; Smith, Kevin M.

    1992-06-01

    In order to evaluate the effect of substituents in photosensitizing activity, a series of long wavelength absorbing photosensitizers related to pyropheophorbides, bacteriopheophorbides, and benzoporphyrin derivatives were synthesized. Pheophorbide dimers, covalently joining two molecules of pyropheophorbide-a and bacteriopheophorbide-a with lysine as a cross-link were also prepared. The syntheses and spectroscopic properties of these compounds are discussed. Some of these compounds were tested for in vivo photosensitizing activity vis-a-vis Photofrin IITM, using the standard screening system of DBA/2 mice bearing transplanted SMT/F tumors. The preliminary in vivo results suggest that replacement of substituents at peripheral positions of the macrocycles causes a significant difference in photosensitizing efficacy.

  16. Inverted organic photosensitive devices

    DOEpatents

    Forrest, Stephen R.; Bailey-Salzman, Rhonda F.

    2016-12-06

    The present disclosure relates to organic photosensitive optoelectronic devices grown in an inverted manner. An inverted organic photosensitive optoelectronic device of the present disclosure comprises a reflective electrode, an organic donor-acceptor heterojunction over the reflective electrode, and a transparent electrode on top of the donor-acceptor heterojunction.

  17. Retrospective analysis of drug photosensitivity in Norway

    NASA Astrophysics Data System (ADS)

    Selvaag, Edgar

    1999-02-01

    Reports on adverse drug reactions, as they were recorded at the Norwegian Medicines Control Authority beginning in the year 1970 up to 1994 were analyzed especially with regard to cutaneous reactions and photosensitivity reactions. During the time period, almost 13.000 side effects were reported. Out of these 799 reports involved the skin and appendages, and 64 out of these reports (8%) were classified as photosensitivity reactions. Tetracyclines, diuretics, antihypertensive agents, and urologicals were the drugs which most often caused photosensitivity reactions. In addition, a number of uncommon photosensitizing drugs were reported. The risk for photosensitization is discussed on the background of experimental data and the prescription rates of these substances.

  18. Refining the Bengal Fan stratigraphy - A first correlation of IODP Expedition 354 results and seismic data from the Bay of Bengal

    NASA Astrophysics Data System (ADS)

    Schwenk, Tilmann; Spiess, Volkhard; Bergmann, Fenna; France-Lanord, Christian; Klaus, Adam

    2016-04-01

    The Bengal Fan covers the floor of the entire Bay of Bengal from the continental margins of India and Bangladesh to the sediment-filled Sunda Trench off Myanmar and the Andaman Islands, and along the west side of the Ninetyeast Ridge. The deposition and progradation of the Bengal Fan started in the Eocene after the collision of India with Asia resulting in the build-up of the Himalaya and the formation of a large proto-Bay of Bengal. Continued convergence of the Indian and Australian plates with the Southeast Asian plate reduced the size of the bay and focused the source of turbidites finally into the present Bengal Basin, Bangladesh shelf, and the shelf canyon "Swatch of no Ground". Today, the Bengal Fan is mainly fed by the sediment load of the Ganges and Brahmaputra rivers, which drain the Himalayas at its southern and northern slope, respectively, and deliver their load to the delta in the Bengal Basin, to the Bengal Shelf and to the deep sea fan. Thus the Bengal Fan is a suitable recorder to study interactions among the growth of the Himalaya and Tibet, the development of the Asian monsoon, and processes affecting the carbon cycle and global climate. Because sedimentation in the Bengal Fan responds to both, climate and tectonic processes, its terrigenous sediment records the past evolution of both the Himalaya and regional climate. This evolution is also expressed in the stratigraphy of the fan in terms of unconformities and key horizons, average sedimentation rates as a function of distance from the basement ridges at 85°E and 90°E and the presence or absence of channel-levee systems. The histories of the Himalaya/Tibetan system and the Asian monsoon require sampling different periods of time with different levels of precision. Therefore IODP Expedition 354 drilled in February-March 2015 a seven site, 320 km-long transect across the Bengal Fan at 8°N. This strategy has been chosen because sediment transport took place by turbidity currents following

  19. Population Growth Parameters of Rose Aphid, Macrosiphum rosae (Hemiptera: Aphididae) on Different Rose Cultivars.

    PubMed

    Golizadeh, A; Jafari-Behi, V; Razmjou, J; Naseri, B; Hassanpour, M

    2017-02-01

    The rose aphid, Macrosiphum rosae (L.), is one of the most important pests on rose plants (Rosa spp.) with a worldwide distribution. As resistance indices, the development, survivorship, and reproduction of this aphid were evaluated on 10 rose cultivars, including Bella Vita, Cool Water, Dolce Vita, Maroussia, Orange Juice, Pinkpromise, Roulette, Tea, Valentine, and Persian Yellow in laboratory at 25 ± 1°C, 65 ± 5% relative humidity, and photoperiod of 16:8 (L/D) h. Rose aphid successfully survived on all 10 rose cultivars, although mortality rate was higher on Tea and Bella Vita. The number of offspring per female differed significantly among the tested rose cultivars, and ranged from 9.2 on Tea to 38.7 nymphs on Orange Juice. Population growth parameters were significantly affected by rose cultivars. The longest mean generation time (T) was observed on Bella Vita (14.8 days) and Tea (14.7 days) and the shortest on Orange Juice (10.0 days). The net reproductive rate (R 0 ) ranged from 6.9 on Tea to 33.2 nymphs on Orange Juice cultivar. Correspondingly, the highest value of intrinsic rate of increase (r m ) was observed on Orange Juice (0.348 day -1 ) and lower values on Tea (0.131 day -1 ) followed by Bella Vita (0.154 day -1 ). Cluster analysis of all the measured parameters of rose aphid on different rose cultivars revealed that Tea and Bella Vita were relatively resistant to M. rosae. These findings could be useful in developing an integrated pest management (IPM) program for this aphid in urbanized areas and commercial rose potting.

  20. Human photosensitivity: from pathophysiology to treatment.

    PubMed

    Verrotti, A; Tocco, A M; Salladini, C; Latini, G; Chiarelli, F

    2005-11-01

    Photosensitivity is a condition detected on the electroencephalography (EEG) as a paroxysmal reaction to Intermittent Photic Stimulation (IPS). This EEG response, elicited by IPS or by other visual stimuli of daily life, is called Photo Paroxysmal Response (PPR). PPRs are well documented in epileptic and non-epileptic subjects. Photosensitivity rarely in normal individuals evolves into epilepsy. Photosensitive epilepsy is a rare refex epilepsy characterized by seizures in photosensitive individuals. The development of modern technology has increased the exposition to potential seizure precipitants in people of all ages, but especially in children and adolescents. Actually, videogames, computers and televisions are the most common triggers in daily life of susceptible persons. The mechanisms of generation of PPR are poorly understood, but genetic factors play an important rule. The control of visually induced seizures has, generally a good prognosis. In patients known to be visually sensitive, avoidance of obvious source and stimulus modifications are very important and useful to seizure prevention, but in the large majority of patients with epilepsy and photosensitivity antiepileptic drugs are needed.

  1. Behavior of Multiclass Pesticide Residue Concentrations during the Transformation from Rose Petals to Rose Absolute.

    PubMed

    Tascone, Oriane; Fillâtre, Yoann; Roy, Céline; Meierhenrich, Uwe J

    2015-05-27

    This study investigates the concentrations of 54 multiclass pesticides during the transformation processes from rose petal to concrete and absolute using roses spiked with pesticides as a model. The concentrations of the pesticides were followed during the process of transforming the spiked rose flowers from an organic field into concrete and then into absolute. The rose flowers, the concrete, and the absolute, as well as their transformation intermediates, were analyzed for pesticide content using gas chromatography/tandem mass spectrometry. We observed that all the pesticides were extracted and concentrated in the absolute, with the exception of three molecules: fenthion, fenamiphos, and phorate. Typical pesticides were found to be concentrated by a factor of 100-300 from the rose flowers to the rose absolute. The observed effect of pesticide enrichment was also studied in roses and their extracts from four classically phytosanitary treated fields. Seventeen pesticides were detected in at least one of the extracts. Like the case for the spiked samples in our model, the pesticides present in the rose flowers from Turkey were concentrated in the absolute. Two pesticides, methidathion and chlorpyrifos, were quantified in the rose flowers at approximately 0.01 and 0.01-0.05 mg kg(-1), respectively, depending on the treated field. The concentrations determined for the corresponding rose absolutes were 4.7 mg kg(-1) for methidathion and 0.65-27.25 mg kg(-1) for chlorpyrifos.

  2. Probing Photosensitization by Functionalized Carbon Nanotubes

    EPA Science Inventory

    Carbon nanotubes (CNTs) photosensitize the production of reactive oxygen species that can damage organisms by biomembrane oxidation or mediate CNTs' environmental transformations. The photosensitized nature of derivatized carbon nanotubes from various synthetic methods, and thus ...

  3. EVALUATION AND IMPORTANCE OF SELECTED MICROBIOLOGICAL METHODS IN THE DIAGNOSIS OF HUMAN BRUCELLOSIS

    PubMed Central

    Šiširak, Maida; Hukić, Mirsada

    2009-01-01

    Brucellosis is an important public health problem in Bosnia and Herzegovina. The diagnosis of bru-cellosis in the country without any experiences with this kind of infection may be very difficult. The aim of this study was to evaluate diagnostic methods: Rose Bengal test, blood cultures and ELISA IgM and IgG in the patients with brucellosis. The study included 91 brucellosis patients in the period 2004 to 2007. All the patients were treated at the Clinic for Infectious Diseases, University of Sarajevo Clinics Centre. Blood cultures were positive in 28/91 (30, 8%) patients. This method often needs a long period of incubation and specimens need to be obtained early. These limitations make serology the most useful tool for the laboratory diagnosis of Brucella infection. Rose Bengal is a rapid plate agglutination test, very sensitive irrespective of the stage of the disease. In our study, Rose Bengal test was positive in all patients 91/91 (100, 0%). Brucella IgM antibodies with ELISA were positive in 59/91 (64, 8%). Brucella IgG antibodies with ELISA were positive in 51/91 (56%). In order to determine the diagnostic value of the different tests, we compared the sensitivity among test-methods: Rose Bengal test-100.0%, blood culture-30.8%, ELISA IgM-64.8% and ELISA IgG-56.1%. Sensitivity of test methods was different in the different stages of illness. It is necessary to use combination of different tests such are blood culture, Rose Bengal test and ELISA in order to ensure the diagnosis. Rose Bengal test is excellent for the screening. Blood culture is a method of choice for the diagnosis acute infection. ELISA is a very good method for the diagnostic chronic disease and relapse. PMID:19754473

  4. Comparison of counter-immunoelectrophoresis with other serological tests in the diagnosis of human brucellosis

    PubMed Central

    Díaz, R.; Maravi-Poma, E.; Rivero, A.

    1976-01-01

    Sera from 65 persons with clinical brucellosis were employed in a comparison of standard and rapid serological tests. The results obtained with the Rose Bengal test correlated very well with those of the standard tube agglutination test, whereas results with the rapid plate agglutination test and the Coombs (antiglobulin) test were inferior. Absorption of patients' sera with specific anti-human immunoglobulin sera showed that IgM was active in the Rose Bengal test but not in the Coombs test, whereas IgG and IgA were active in both tests. In addition to the A & M antigen, which plays the most important role in the agglutination, Rose Bengal, and Coombs tests, other antigenic fractions of Brucella were examined in precipitation tests. A protein antigen reacted with 94% of the sera in counter-immunoelectrophoresis. On the basis of the results with both groups of sera, the Rose Bengal test and counter-immunoelectrophoresis appear to be the most promising methods for diagnosing clinical brucellosis. The tests differ qualitatively since different Brucella antigens are employed. PMID:791532

  5. Scent evolution in Chinese roses

    PubMed Central

    Scalliet, Gabriel; Piola, Florence; Douady, Christophe J.; Réty, Stéphane; Raymond, Olivier; Baudino, Sylvie; Bordji, Karim; Bendahmane, Mohammed; Dumas, Christian; Cock, J. Mark; Hugueney, Philippe

    2008-01-01

    The phenolic methyl ether 3,5-dimethoxytoluene (DMT) is a major scent compound of many modern rose varieties, and its fragrance participates in the characteristic “tea scent” that gave their name to Tea and Hybrid Tea roses. Among wild roses, phenolic methyl ether (PME) biosynthesis is restricted to Chinese rose species, but the progenitors of modern roses included both European and Chinese species (e.g., Rosa chinensis cv Old Blush), so this trait was transmitted to their hybrid progeny. The last steps of the biosynthetic pathways leading to DMT involve two methylation reactions catalyzed by the highly similar orcinol O-methyltransferases (OOMT) 1 and 2. OOMT1 and OOMT2 enzymes exhibit different substrate specificities that are consistent with their operating sequentially in DMT biosynthesis. Here, we show that these different substrate specificities are mostly due to a single amino acid polymorphism in the phenolic substrate binding site of OOMTs. An analysis of the OOMT gene family in 18 species representing the diversity of the genus Rosa indicated that only Chinese roses possess both the OOMT2 and the OOMT1 genes. In addition, we provide evidence that the Chinese-rose-specific OOMT1 genes most probably evolved from an OOMT2-like gene that has homologues in the genomes of all extant roses. We propose that the emergence of the OOMT1 gene may have been a critical step in the evolution of scent production in Chinese roses. PMID:18413608

  6. Roses for Autism

    ERIC Educational Resources Information Center

    Tomaino, Robert

    2011-01-01

    This article discusses Roses for Autism, a program that provides training, guidance and employment opportunities for older students and adults on the autistic spectrum. Roses for Autism tackles one of the biggest challenges currently facing the autism community--a disproportionally high unemployment rate that hovers around 88 percent. Although a…

  7. First report of Rose rosette virus associated with rose rosette disease in Rosa hybrida in Minnesota

    USDA-ARS?s Scientific Manuscript database

    A Rosa hybrida plant was identified with rose rosette disease symptoms and was positive for Rose rosette virus (RRV) by reverse transcription PCR. It is important to monitor routinely roses for RRV symptoms and to test and rogue symptomatic plants. This is the first report of RRV infecting roses in ...

  8. High throughput photo-oxidations in a packed bed reactor system.

    PubMed

    Kong, Caleb J; Fisher, Daniel; Desai, Bimbisar K; Yang, Yuan; Ahmad, Saeed; Belecki, Katherine; Gupton, B Frank

    2017-12-01

    The efficiency gains produced by continuous-flow systems in conducting photochemical transformations have been extensively demonstrated. Recently, these systems have been used in developing safe and efficient methods for photo-oxidations using singlet oxygen generated by photosensitizers. Much of the previous work has focused on the use of homogeneous photocatalysts. The development of a unique, packed-bed photoreactor system using immobilized rose bengal expands these capabilities as this robust photocatalyst allows access to and elaboration from these highly useful building blocks without the need for further purification. With this platform we were able to demonstrate a wide scope of singlet oxygen ene, [4+2] cycloadditions and heteroatom oxidations. Furthermore, we applied this method as a strategic element in the synthesis of the high-volume antimalarial artemisinin. Copyright © 2017. Published by Elsevier Ltd.

  9. Attempted photodynamic therapy against patagial squamous cell carcinoma in an African rose-ringed parakeet (Psittacula krameri).

    PubMed

    Suedmeyer, Wm Kirk; Henry, Carolyn; McCaw, Dudley; Boucher, Magalie

    2007-12-01

    A 5-yr-old female African rose-ringed parakeet (Psittacula krameri) presented with an ulcerated mass in the medial postpatagial area of the right wing. Biopsy specimens of the mass demonstrated a well-differentiated squamous cell carcinoma. Photodynamic therapy resulted in tumor cell necrosis and initial reduction in tumor burden, but complete remission was not achieved. Based on this and other avian cases, it appears that photodynamic therapy designed to eradicate squamous cell carcinoma in avian species using protocols modeled after canine, feline, and human photodynamic therapy protocols may not be useful. It is hypothesized that differences in light penetration, photosensitizing agent pharmacokinetics, and wound healing properties in avian species necessitate alteration of photodynamic therapy protocols if this treatment modality is to be effective in avian oncology.

  10. Eradication of bacterial species via photosensitization

    NASA Astrophysics Data System (ADS)

    Golding, Paul S.; Maddocks, L.; King, Terence A.; Drucker, D. B.

    1999-02-01

    Photosensitization and inactivation efficacy of three bacterial species: Prevotella nigrescens, Staphylococcus aureus and Escherichia coli have been investigated. Samples of Staphylococcus aureus and Escherichia coli were treated with the triphenylmethane dye malachite green isothiocyanate and exposed to light from a variety of continuous and pulsed light sauces at a wavelength of approximately 630 nm. Inactivation of the Gram-positive species Staphylococcus aureus was found to increase with radiation dose, whilst Gram-negative Escherichia coli was resistant to such treatment. Samples of the pigmented species Prevotella nigrescens were found to be inactivated by exposure to light alone. The mechanism of photosensitization and inactivation of Staphylococcus aureus with malachite green isothiocyanate is addressed. The possible roles of the excited triplet state of the photosensitizer, the involvement of molecular oxygen, and the bacterial cell wall are discussed. Photosensitization may provide a way of eliminating naturally pigmented species responsible for a variety of infections, including oral diseases such as gingivitis and periodontitis.

  11. Alternaria toxin-induced resistance in rose plants against rose aphid (Macrosiphum rosivorum): effect of tenuazonic acid.

    PubMed

    Yang, Fa-zhong; Yang, Bin; Li, Bei-bei; Xiao, Chun

    2015-04-01

    Many different types of toxins are produced by the fungus, Alternaria alternata (Fr.) Keissler. Little is known, however, regarding the influence of these toxins on insects. In this study, we investigated the toxin-induced inhibitory effects of the toxin produced by A. alternata on the rose aphid, Macrosiphum rosivorum, when the toxin was applied to leaves of the rose, Rosa chinensis. The results demonstrated that the purified crude toxin was non-harmful to rose plants and rose aphids, but had an intensive inhibitory effect on the multiplication of aphids. The inhibitory index against rose aphids reached 87.99% when rose plants were sprayed with the toxin solution at a low concentration. Further results from bioassays with aphids and high performance liquid chromatography (HPLC) analyses demonstrated that tenuazonic acid (TeA) was one of the most important resistance-related active components in the crude toxin. The content of TeA was 0.1199% in the crude toxin under the HPLC method. Similar to the crude toxin, the inhibitory index of pure TeA reached 83.60% 15 d after the rose plants were sprayed with pure TeA solution at the lower concentration of 0.060 μg/ml, while the contents of residual TeA on the surface and in the inner portion of the rose plants were only 0.04 and 0.00 ng/g fresh weight of TeA-treated rose twigs, respectively, 7 d after the treatment. Our results show that TeA, an active component in the A. alternata toxin, can induce the indirect plant-mediated responses in rose plants to intensively enhance the plant's resistances against rose aphids, and the results are very helpful to understand the plant-mediated interaction between fungi and insects on their shared host plants.

  12. ROSE Version 1.0

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Quinlan, D.; Yi, Q.; Buduc, R.

    2005-02-17

    ROSE is an object-oriented software infrastructure for source-to-source translation that provides an interface for programmers to write their own specialized translators for optimizing scientific applications. ROSE is a part of current research on telescoping languages, which provides optimizations of the use of libraries in scientific applications. ROSE defines approaches to extend the optimization techniques, common in well defined languages, to the optimization of scientific applications using well defined libraries. ROSE includes a rich set of tools for generating customized transformations to support optimization of applications codes. We currently support full C and C++ (including template instantiation etc.), with Fortran 90more » support under development as part of a collaboration and contract with Rice to use their version of the open source Open64 F90 front-end. ROSE represents an attempt to define an open compiler infrastructure to handle the full complexity of full scale DOE applications codes using the languages common to scientific computing within DOE. We expect that such an infrastructure will also be useful for the development of numerous tools that may then realistically expect to work on DOE full scale applications.« less

  13. Crust And Upper Mantle Structure Of The Bengal Basin And Bay Of Bengal From Surface Wave Group Velocity Dispersion Studies

    NASA Astrophysics Data System (ADS)

    Dhali, K. K.; Majhi, S.; Mitra, S.; Priestley, K.

    2007-12-01

    Fundamental mode Rayleigh and Love wave group velocity dispersion for paths crossing the Bay of Bengal have been calculated for earthquakes in the Indo-Burman arc and the Andaman-Sumatra subduction zone recorded at seismographs in the eastern part of Peninsula India and Sri Lanka. The ray-path coverage in this study provides a better spatial sampling than any previous studies of the region. The individual dispersion curves range from 12 to 70~s and have been clustered in four spatial groups to form average dispersion curves representative of the Bengal basin, northern, central and southern Bay of Bengal. These average dispersion curves for Rayleigh and Love waves are jointly inverted to obtain shear wave velocity structure of the lithosphere. The higher frequencies/shorter periods (12--30~s) used in the inversion constrains the sediment shear wave speed and thickness while the longer periods provide information of the upper mantle structure. The results show a remarkable increase in the sediments thickness along the Bengal Fan from south to north ranging from 6 km, around the southern tip of India, to 23 km beneath the Bengal basin. The shear wave velocity models reveal a sediment saturation beyond 7-10 km of burial leading to metamorphism and eventual increase in velocity to continent like material with depth. The average crustal thickness (loose sediments overlying consolidated sediments followed by metasediments and oceanic crust) is anomalously continental (~20-36 km) rather than being simply oceanic crust overlain by sediments. The average shear wave velocity is about 3.5-3.8 km/s which is more representative of continental crusts. Finally the low velocity zone in the uppermost mantle is possibly an effect of the expected increase in temperature due to blanketing of the fan sediments over the Bay of Bengal crust. The misfits to parts of the dispersion data using a 1D isotropic model provides an indication of the presence of polarization anisotropy in the

  14. Skin photosensitivity as a model in photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Richter, Anna M.; Jain, Ashok K.; Canaan, Alice J.; Meadows, Howard; Levy, Julia G.

    1996-01-01

    Skin photosensitivity is the most common side effect of photodynamic therapy (PDT) and in clinical situations needs to be avoided or at least minimized. However, because of the accessibility of skin tissue, skin photosensitivity represents a useful test system in vivo for evaluation of the pharmacokinetics of photosensitizers and light sources. Pig skin resembles in many aspects human skin and, therefore, is most suitable for these tests. Using pig skin photosensitivity as an end point, we evaluate the effect of cell loading with a photosensitizer, benzoporphyrin derivative (BPD verteporfin) following its intravenous administration either as a rapid bolus or slow infusion. Skin response to light activation indicated a very similar cell content of BPD. These results were in agrement with those obtained in an in vitro model. In addition, in the same pig skin photosensitivity model we compared the efficiency of activation of BPD with either laser (690 plus or minus 3 nm) or light-emitting diode (LED; 690 plus or minus 12 nm) light. Results indicated the equivalency of the two light sources in this test system, with LED light being slightly more efficient, due possibly to a fluence rate lower than laser light.

  15. Lipid based nanocarriers system for topical delivery of photosensitizers.

    PubMed

    Md, Shadab; Haque, Shadabul; Madheswaran, Thiagarajan; Zeeshan, Farrukh; Meka, Venkata Srikanth; Radhakrishnan, Ammu K; Kesharwani, Prashant

    2017-08-01

    Topical photodynamic therapy (PDT) is a non-invasive technique used in the treatment of malignant and non-malignant skin diseases. It offers great promise because of its simplicity, enhanced patient compliance, localisation of the photosensitizer, as well as the use of light and oxygen to achieve photocytotoxicity. Despite progress in photosensitizer-mediated topical PDT, its clinical application is limited by poor penetration of photosensitizers through the skin. Therefore, much effort has been made to develop nanocarriers that can tackle the challenges of conventional photosensitizer-mediated PDT for topical delivery. This review discusses recent data on the use of different types of lipid-based nanocarriers in delivering photosensitizer for topical PDT. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Mechanism to preserve phrenic nerve function during photosensitization reaction: drug uptake and photosensitization reaction effect on electric propagation

    NASA Astrophysics Data System (ADS)

    Takahashi, Haruka; Hamada, Risa; Ogawa, Emiyu; Arai, Tsunenori

    2018-02-01

    To study a mechanism of phrenic nerve preservation phenomena during a photosensitization reaction, we investigated an uptake of talaporfin sodium and photosensitization reaction effect on an electric propagation. Right phrenic nerve was completely preserved after superior vena cava isolations using the photosensitization reaction in canine animal experiments, in spite of adjacent myocardium was electrically blocked. We predicted that low drug uptake and/or low photosensitization reaction effect on the nerve might be a mechanism of that phenomena. To investigate uptake to various nerve tissue, a healthy extracted crayfish ventral nerve cord and an extracted porcine phrenic nerve were immersed in 20 μg/ml talaporfin sodium solution for 0-240 min. The mean talaporfin sodium fluorescence brightness increased depending on the immersion time. This brightness saturated around the immersion time of 120 min. We found that talaporfin sodium uptake inside the perineurium which directly related to the electric propagation function was lower than that of outside in the porcine phrenic nerve. To investigate photosensitization reaction effect on electric propagation, the crayfish nerve was immersed into the same solution for 15 min and irradiated by a 663 nm laser light with 120 mW/cm2. Since we found the action potential disappeared when the irradiation time was 25-65 s, we consider that the crayfish nerve does not tolerant to the photosensitization reaction on electric propagation function at atmospheric pressure. From these results, we think that the low uptake of talaporfin sodium inside the perineurium and low oxygen partial pressure of nerve might be the possible mechanism to preserve phrenic nerve in vivo.

  17. Photodynamic treatment of culture medium containing serum induces long-lasting toxicity in vitro.

    PubMed

    Olivier, David; Douillard, Samuel; Lhommeau, Isabelle; Patrice, Thierry

    2009-10-01

    Photodynamic therapy (PDT) produces singlet oxygen and reactive oxygen species (ROS) that damage tumor cells and the vasculature. The resulting effect is a balance between photo-oxidations through primary or secondary ROS and scavenging activity. Sensitizers are distributed in the extracellular space before and during cell sensitization, suggesting that PDT could act directly on cell structures and on extracellular compartments, including sera. In this study we endeavored to determine whether the application of PDT to culture medium could affect cell survival. Culture medium [RPMI 1640 supplemented with fetal calf serum (FCS)] was incubated with Rose Bengal and irradiated before being added to cells for various contact times as a replacement for untreated medium. Cells were then kept in darkness until the survival assay. Treated medium reduced cell survival by up to 40% after 30 min of contact for 10 microg/ml of Rose Bengal and 20 J/cm(2). Rose Bengal or m-THPC alone or irradiated in water had no effect. This effect was dependent on the doses of Rose Bengal and light and decreased when FCS was replaced by human serum mixed with FCS. The reduction in survival observed with treated medium was more pronounced when the cell doubling time was shorter. Analysis of ROS or peroxide production in treated medium by DCFH added at the end of irradiation of Rose Bengal in serum-containing medium revealed a long-lasting oxidizing activity. Our findings support the hypothesis of an ROS- or peroxide-mediated, PDT-induced, long-lasting cell toxicity.

  18. Space Rose Pleases the Senses

    NASA Technical Reports Server (NTRS)

    2002-01-01

    International Flavors and Fragrances (IFF), Inc., discovered a new scent by flying a miniature rose plant aboard NASA's Space Shuttle Discovery Flight STS-95. IFF and the Wisconsin Center for Space Automation and Robotics (WCSAR) partnered to fly the rose plant in the commercial plant research facility, ASTROCULTURE(TM), for reduced-gravity environment research. IFF commercialized the space rose note, which is now a fragrance ingredient in a perfume developed by Shiseido Cosmetics (America), Ltd. In addition to providing a light crisp scent, the oil from the space rose can also serve as a flavor enhancer. ASTROCULTURE(TM) is a trademark of the Wisconsin Center for Space Automation and Robotics.

  19. Survey of Prunus necrotic ringspot virus in Rose and Its Variability in Rose and Prunus spp.

    PubMed

    Moury, B; Cardin, L; Onesto, J P; Candresse, T; Poupet, A

    2001-01-01

    ABSTRACT A survey for viruses in rose propagated in Europe resulted in detection of only Prunus necrotic ringspot virus (PNRSV) among seven viruses screened. Four percent of cut-flower roses from different sources were infected with PNRSV. Progression of the disease under greenhouse conditions was very slow, which should make this virus easy to eradicate through sanitary selection. Comparison of the partial coat protein gene sequences for three representative rose isolates indicated that they do not form a distinct phylogenetic group and show close relations to Prunus spp. isolates. However, a comparison of the reactivity of monoclonal antibodies raised against these isolates showed that the most prevalent PNRSV serotype in rose was different from the most prevalent serotype in Prunus spp. All of the 27 rose isolates tested infected P. persica seedlings, whereas three of the four PNRSV isolates tested from Prunus spp. were poorly infectious in Rosa indica plants. These data suggest adaptation of PNRSV isolates from Prunus spp., but not from rose, to their host plants. The test methodologies developed here to evaluate PNRSV pathogenicity in Prunus spp. and rose could also help to screen for resistant genotypes.

  20. CHD2 variants are a risk factor for photosensitivity in epilepsy

    PubMed Central

    Myers, Candace T.; Leu, Costin; de Kovel, Carolien G. F.; Afrikanova, Tatiana; Cordero-Maldonado, Maria Lorena; Martins, Teresa G.; Jacmin, Maxime; Drury, Suzanne; Krishna Chinthapalli, V.; Muhle, Hiltrud; Pendziwiat, Manuela; Sander, Thomas; Ruppert, Ann-Kathrin; Møller, Rikke S.; Thiele, Holger; Krause, Roland; Schubert, Julian; Lehesjoki, Anna-Elina; Nürnberg, Peter; Lerche, Holger; Palotie, Aarno; Coppola, Antonietta; Striano, Salvatore; Gaudio, Luigi Del; Boustred, Christopher; Schneider, Amy L.; Lench, Nicholas; Jocic-Jakubi, Bosanka; Covanis, Athanasios; Capovilla, Giuseppe; Veggiotti, Pierangelo; Piccioli, Marta; Parisi, Pasquale; Cantonetti, Laura; Sadleir, Lynette G.; Mullen, Saul A.; Berkovic, Samuel F.; Stephani, Ulrich; Helbig, Ingo; Crawford, Alexander D.; Esguerra, Camila V.; Kasteleijn-Nolst Trenité, Dorothee G. A.

    2015-01-01

    Photosensitivity is a heritable abnormal cortical response to flickering light, manifesting as particular electroencephalographic changes, with or without seizures. Photosensitivity is prominent in a very rare epileptic encephalopathy due to de novo CHD2 mutations, but is also seen in epileptic encephalopathies due to other gene mutations. We determined whether CHD2 variation underlies photosensitivity in common epilepsies, specific photosensitive epilepsies and individuals with photosensitivity without seizures. We studied 580 individuals with epilepsy and either photosensitive seizures or abnormal photoparoxysmal response on electroencephalography, or both, and 55 individuals with photoparoxysmal response but no seizures. We compared CHD2 sequence data to publicly available data from 34 427 individuals, not enriched for epilepsy. We investigated the role of unique variants seen only once in the entire data set. We sought CHD2 variants in 238 exomes from familial genetic generalized epilepsies, and in other public exome data sets. We identified 11 unique variants in the 580 individuals with photosensitive epilepsies and 128 unique variants in the 34 427 controls: unique CHD2 variation is over-represented in cases overall (P = 2·17 × 10−5). Among epilepsy syndromes, there was over-representation of unique CHD2 variants (3/36 cases) in the archetypal photosensitive epilepsy syndrome, eyelid myoclonia with absences (P = 3·50 × 10−4). CHD2 variation was not over-represented in photoparoxysmal response without seizures. Zebrafish larvae with chd2 knockdown were tested for photosensitivity. Chd2 knockdown markedly enhanced mild innate zebrafish larval photosensitivity. CHD2 mutation is the first identified cause of the archetypal generalized photosensitive epilepsy syndrome, eyelid myoclonia with absences. Unique CHD2 variants are also associated with photosensitivity in common epilepsies. CHD2 does not encode an ion channel, opening new avenues for research

  1. Photosensitivity of layered semiconductor propolis heterocontact

    NASA Astrophysics Data System (ADS)

    Drapak, Stepan I.; Orletskii, Volodymyr B.; Bahtinov, Anatolii P.; Kovalyuk, Zakhar D.; Fotiy, Vasyl D.

    2003-03-01

    Room temperature photosensitivity and its spectral distribution are investigated for a hetercontact between a layered semiconductor (p-InSe) and a biological entity (propolis). The obtained heterocontacts has a maximum photosensitivity >= 10^4 V/W. It is shown that the form of spectral sensitivity curve depends on the way of the heterocontact preparation. The long-wave edge of relative quantum efficiency varies from hν =1.2 eV (the energy gap for InSe at T=300 K) to 1.6 eV depending on a state of aggregation of propolis. The maximum photosensitivity in the long-wave spectral range takes place when the propolis layer is under illumination. The obtained peculiarities of the photoelectrical properties cannot be explained in the framework of the classical description of photosensitivity spectral description (the window effect) what follows from the optical absorption measurements for InSe and propolis in the range hν <= 1.2 eV. Impurity states in the energy gap of InSe and states at the heterocontact interface (a classical case of isotype p-p heterojunction) also do not give an appropriate explanation. To interpret the obtained results the complexity of the chemical composition of propolis, a product from honey bee, must be taken into account.

  2. Magnetic resonance spectroscopy findings in photosensitive idiopathic generalized epilepsy.

    PubMed

    Aydin-Ozemir, Zeynep; Terzibasioglu, Ege; Altindag, Ebru; Sencer, Serra; Baykan, Betul

    2010-01-01

    Studies investigating the pathophysiology of epileptic photosensitivity indicate variable involvement of particular brain regions. Our aim was to identify metabolic differences between photosensitive idiopathic generalized epilepsy (IGE) patients and nonphotosensitive IGE patients and normal healthy subjects by using Magnetic Resonance Spectroscopy (MRS). Fourteen patients diagnosed with photosensitive IGE were investigated. The control groups consisted of 14 age- and sex-matched healthy volunteers and 14 IGE patients without photosensitivity. MRS measurements of N-acetylaspartate (NAA), choline-containing compounds (Cho), creatine (Cr) were performed in the frontal and occipital cortex and the thalamus bilaterally using a stimulated echo acquisition mode (STEAM) technique with a voxel size of 20 x 20 x 20 mm. The values of the patients with IGE were compared with those of the normal controls and within subgroups according to the clinical variables by appropriate statistical tests. Photosensitive IGE patients showed significantly decreased concentrations of NAA in the right frontal lobe and left thalamus, decreased NAA/Cr ratio in left thalamus and significantly increased concentrations of Cho/Cr ratio in the right frontal lobe and NAA/Cr in the left occipital lobe when compared to normal controls. Furthermore, left occipital NAA concentration increased and left thalamus NAA/Cr ratios were decreased from the IGE patients without photosensitivity but without reaching statistical significance. Our results support previous MR studies suggesting an asymmetrical neuronal dysfunction in favor of the dominant occipital cortex and thalamus in photosensitive IGE patients.

  3. Novel visible light activated type 1 photosensitizers

    NASA Astrophysics Data System (ADS)

    Rajagopalan, Raghavan; Karwa, Amolkumar; Poreddy, Amruta R.; Lusiak, Przemyslaw M.; Pandurangi, Raghoottama S.; Cantrell, Gary L.; Dorshow, Richard B.

    2010-02-01

    Photodynamic therapy of tumors involving Type 2 photosenstizers has been conspicuously successful, but the Type 1 process, in contrast, has not received much attention despite its considerable potential. Accordingly, several classes of molecules containing fragile bonds such as azido (-N=N=N), azo (-N=N-), and oxaza (-N-O-) functional groups that produce reactive intermediates such as radicals and nitrenes upon photoexcitation with visible light were prepared and tested for cell viability using U397 leukemia cell line. The cells were incubated with the photosensitizer at various concentrations, and were illuminated for 5, 10, and 20 minutes. The results show that all the photosensitizers caused cell death compared to the controls when exposed to both the photosensitizers and light.

  4. Photosensitizer fluorescence emission during photodynamic therapy applied to dermatological diseases

    NASA Astrophysics Data System (ADS)

    Salas-García, I.; Fanjul-Vélez, F.; Ortega-Quijano, N.; Arce-Diego, J. L.

    2011-09-01

    Photodynamic Therapy (PDT) is an optical treatment modality that allows malignant tissue destruction. It is based on the administration of a photosensitizer and the posterior irradiation by an optical source. Photosensitizer molecules absorb the excitation light photons triggering a series of photochemical reactions in the presence of oxygen in the target tissue. During such interactions it is produced the de-excitation of the photosensitizer molecules in the singlet excited state which return to their minimum energy state by emitting fluorescence photons. These days, there are fixed clinical PDT protocols that make use of a particular optical dose and photosensitizer amount. However treatment response varies among patients and the type of pathology. In order to adjust an optimal dosimetry, the development of accurate predictive models plays an important role. The photosensitizer fluorescence can be used to estimate the degradation of the photoactive agent and as an implicit dosimetric measurement during treatment. However it is complex to know the fluorescence dependence with the depth in the tumor from observed fluorescence in the pathology surface. We present a first approach to predict the photosensitizer fluorescence dependence with depth during the PDT treatment applied to a skin disease commonly treated in the dermatological clinical practice. The obtained results permit us to know the photosensitizer temporal fluorescence evolution in different points of the tumor sample during the photochemical reactions involved in PDT with a predictive purpose related to the treatment evolution. The model presented also takes into account the distribution of a topical photosensitizer, the propagation of light in a biological media and the subsequent photochemical interactions between light and tissue. This implies that different parameters related with the photosensitizer distribution or the optical source characteristics could be adjusted to provide a specific treatment

  5. Solar energy conversion and storage by using Rose Extract as natural dye and nitrilotriacetic acid as reductant in photogalvanic cell

    NASA Astrophysics Data System (ADS)

    Yadav, Sushil Kumar

    2018-05-01

    Photogalvanic effect was studied in Photogalvanic cell containing Rose Extract was used as Natural Dye (Photosensitizer), Nitrilotriacetic acid (NTA) as Reductant. The observed value of photopotential and photocurrent generated by this cell were 872 mV and 176 µA, respectively. The observed power at power point was 82.18 µW and the conversion efficiency was 0.79 %. The fill factor 0.4678 was experimentally determined at the power point of the cell. The photogalvanic cell can be used in dark for 42 min., showing the storage capacity of the cell against charging time was 200 min. The effect of different parameters on electrical output of the cell was observed and a mechanism has also been proposed for the generation of photocurrent in photogalvanic cell.

  6. Volatile constituents of essential oil and rose water of damask rose (Rosa damascena Mill.) cultivars from North Indian hills.

    PubMed

    Verma, Ram Swaroop; Padalia, Rajendra Chandra; Chauhan, Amit; Singh, Anand; Yadav, Ajai Kumar

    2011-10-01

    Rosa damascena Mill. is an important aromatic plant for commercial production of rose oil, water, concrete and absolute. The rose water and rose oil produced under the mountainous conditions of Uttarakhand were investigated for their chemical composition. The major components of rose water volatiles obtained from the bud, half bloom and full bloom stages of cultivar 'Ranisahiba' were phenyl ethyl alcohol (66.2-79.0%), geraniol (3.3-6.6%) and citronellol (1.8-5.5%). The rose water volatiles of cultivar 'Noorjahan' and 'Kannouj' also possessed phenyl ethyl alcohol (80.7% and 76.7%, respectively) as a major component at full bloom stage. The essential oil of cultivar 'Noorjahan' obtained from two different growing sites was also compared. The major components of these oils were citronellol (15.9-35.3%), geraniol (8.3-30.2%), nerol (4.0-9.6%), nonadecane (4.5-16.0%), heneicosane (2.6-7.9%) and linalool (0.7-2.8%). This study clearly showed that the flower ontogeny and growing site affect the composition of rose volatiles. The rose oil produced in this region was comparable with ISO standards. Thus, it was concluded that the climatic conditions of Uttarakhand are suitable for the production of rose oil of international standards.

  7. Photosensitizer nanocarriers modeling for photodynamic therapy applied to dermatological diseases

    NASA Astrophysics Data System (ADS)

    Salas-García, I.; Fanjul-Vélez, F.; Ortega-Quijano, N.; López-Escobar, M.; Arce-Diego, J. L.

    2011-02-01

    Photodynamic Therapy involves the therapeutic use of photosensitizers in combination with visible light. The subsequent photochemical reactions generate reactive oxygen species which are considered the principal cytotoxic agents to induce cell death. This technique has become widely used in medicine to treat tumors and other nonmalignant diseases. However, there are several factors related to illumination or the photosensitizer that limit an optimal treatment outcome. The use of nanoparticles (NP) for PDT has been proposed as a solution to current shortcomings. In this way, there are NPs that act as carriers for photosensitizers, NPs that absorb the light and transfer the energy to the photosensitizer and NPs that are themselves photodynamically active. In dermatology, the use of topical photosensitizers produces a time dependent inhomogeneous distribution within the tumor, where the stratum corneum is the main barrier to the diffusion of the photosensitizer to the deeper layers of skin. This produces an insufficient photosensitizer accumulation in tumor tissues and therefore, a low therapeutic efficiency in the case of deep lesions. This work focuses in the use of NPs as photosensitizer carriers to improve the actual topical drug distribution in malignant skin tissues. We present a mathematical model of PS distribution in tumor tissue using NPs that takes into account parameters related to nanoparticles binding. Once the concentration profile of NPs into tissue is obtained, we use a photochemical model which allows us to calculate the temporal evolution of reactive oxygen species according to PS distribution calculated previously from NPs profile.

  8. Differentiation of the serological response to Yersinia enterocolitica and Brucella abortus in cattle

    PubMed Central

    Corbel, M. J.; Cullen, G. A.

    1970-01-01

    The serological responses of cattle to inoculation with Brucella abortus and Yersinia enterocolitica type IX were compared. Complete cross-reactions were found in serum agglutination, antiglobulin, complement fixation and Rose Bengal plate tests. The cross-reaction between Br. abortus and Y. enterocolitica IX was confirmed by immunodiffusion tests. Although antibodies specific for each organism could also be detected by immunodiffusion tests with high titre rabbit or bovine sera, these tests were insufficiently sensitive for routine diagnostic use. A quantitative Rose Bengal plate test, using Rose Bengal stained Br. abortus and Y. enterocolitica IX, was developed which enabled the antibody responses to the two organisms to be differentiated. The specificity of this test was confirmed by cross-absorption experiments and its sensitivity was sufficient to permit evaluation of all bovine sera giving positive reactions to the serum agglutination test. ImagesFig. 1Fig. 2 PMID:4992575

  9. Non-provocative diagnostics of photosensitivity using visual evoked potentials.

    PubMed

    Vermeulen, Joost; Kalitzin, Stiliyan; Parra, Jaime; Dekker, Erwin; Vossepoel, Albert; da Silva, Fernando Lopes

    2008-04-01

    Photosensitive epilepsy (PSE) is the most common form of reflex epilepsy. Usually, to find out whether a patient is sensitive, he/she is stimulated visually with, e.g. a stroboscopic light stimulus at variable frequency and intensity until a photo paroxysmal response (PPR) occurs. The research described in this work aims to find whether photosensitivity can be detected without provoking a PPR. Twenty-two subjects, 15 with known photosensitivity, were stimulated with visual stimuli that did not provoke a PPR. Using an "evoked response representation", 18 features were analytically derived from EEG signals. Single- and multi-feature classification paradigms were applied to extract those features that separate best subjects with PSE from controls. Two variables in the "evoked response representation", a frequency term and a goodness of fit term to a particular template, appeared to be best suited to make a prediction about the photosensitivity of a subject. Evoked responses appear to carry information about potential PSE. This result can be useful for screening patients for photosensitivity and it may also help to assess in a quantitative way the effectiveness of medical therapy.

  10. Photosensitivity: a current biological overview.

    PubMed

    Elkeeb, Dena; Elkeeb, Laila; Maibach, Howard

    2012-12-01

    The level of interest in photoirritation (phototoxicity) has increased because of the awareness among the scientific community of the increase in the UV portion of the solar spectrum reaching the earth. The need of new chemicals and drugs puts pressure on pre-test methods for side effects, especially interactive adverse effects with UV light. So pre-marketing clinical trials conducted before a new drug is licensed are essential, as such, at the early phases of the discovery process of the drug/chemical, developing an efficacious photosensitivity testing system is prudent to avoid such potential side effects. To review published literature and provide an overview on exogenous photosensitivity and assays used to evaluate the photosensitivity potential of drugs/chemicals. As well as testing considerations by the Regulatory bodies (namely, the Organization for Economic Cooperation and Development, the U.S Food and Drug Administration and the European Union regulatory agencies). We searched medical and scientific search engines as well as websites of the EU and US Regulatory agencies and used keywords such as cutaneous phototoxicity, phototoxicity in vitro assays, phototoxicity in vivo assays and other related terms.

  11. Investigation of human serum albumin (HSA) binding specificity of certain photosensitizers related to pyropheophorbide-a and bacteriopurpurinimide by circular dichroism spectroscopy and its correlation with in vivo photosensitizing efficacy.

    PubMed

    Chen, Yihui; Miclea, Razvan; Srikrishnan, Thamarapu; Balasubramanian, Sathyamangalam; Dougherty, Thomas J; Pandey, Ravindra K

    2005-07-01

    A series of pyropheophorbide-a and bacteriopurpurinimides were investigated to understand the correlation between HSA (site II) binding affinity and in vivo photosensitizing activity. In our study, photosensitizers that bound to site II of HSA produced a significant difference in the circular dichroism spectra of the corresponding complexes, especially at Soret band region of the photosensitizers. Our results suggest that CD spectroscopy of the photosensitizer-HSA complexes could be a valuable tool in screening new photosensitizers before evaluating them for in vivo efficacy.

  12. Scheduling techniques in the Request Oriented Scheduling Engine (ROSE)

    NASA Technical Reports Server (NTRS)

    Zoch, David R.

    1991-01-01

    Scheduling techniques in the ROSE are presented in the form of the viewgraphs. The following subject areas are covered: agenda; ROSE summary and history; NCC-ROSE task goals; accomplishments; ROSE timeline manager; scheduling concerns; current and ROSE approaches; initial scheduling; BFSSE overview and example; and summary.

  13. Increase in the Intensity of Postmonsoon Bay of Bengal Tropical Cyclones

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Balaguru, Karthik; Taraphdar, Sourav; Leung, Lai-Yung R.

    2014-05-28

    The post-monsoon (October-November) tropical cyclone (TC) season in the Bay of Bengal has spawned many of the deadliest storms in recorded history. Here it is shown that the intensity of post-monsoon Bay of Bengal TCs, and the contribution of major TCs to total TC power, increased during 1981-2010. It is found that changes in environmental parameters are responsible for the observed increases in TC intensity. Increases in sea surface temperature and upper ocean heat content made the ocean more conducive to TC development, while enhanced convective instability made the atmosphere more favorable for the growth of TCs. The largest changesmore » in the atmosphere and ocean occurred in the eastern Bay of Bengal, where nearly all major TCs form. These changes are part of positive linear trends, suggesting that the intensity of post-monsoon Bay of Bengal TCs may continue to increase in the future.« less

  14. Development of Smart Phthalocyanine-based Photosensitizers for Photodynamic Therapy

    NASA Astrophysics Data System (ADS)

    Chow, Yun Sang

    Phthalocyanines are versatile functional dyes that have shown great potential in cancer theranostics, especially in photodynamic therapy (PDT). This research work aims to develop "smart" phthalocyanine-based photosensitizers for targeted PDT. This thesis describes the synthesis, spectroscopic characterization, photophysical properties, and in vitro photodynamic activities of several series of carefully designed phthalocyanine-based photosensitizers. Chapter 1 presents an overview of PDT, including its historical development, photophysical mechanisms, and biological mechanisms. Various classes of photosensitizers are introduced with emphasis putting on phthalocyanines, which exhibit ideal characteristics of photosensitizers for PDT. In recent years, several approaches have been used to develop photosensitizers with higher tumor selectivity and minimal skin photosensitivity after PDT. Activatable photosensitizers can provide a "turn on" mechanism to offer an additional control of the specificity of treatment. Photosensitizers can also work cooperatively with the tumor-targeting groups or anticancer drugs so as to achieve targeted or dual therapy, which can enhance the efficacy of PDT. The novel approaches mentioned above have been widely used and combined to form multi-functional photosensitizing agents. These novel concepts and development of PDT are discussed and illustrated with relevant examples at the end of this chapter. To minimize the prolonged skin photosensitivity, photosensitizers that can only be activated by tumor-associated stimuli have been developed. Due to the abnormal metabolism in tumor tissues, their surface usually exhibits a lower pH compared to that of the normal tissues. Also, the pH difference between the intracellular and the physiological environment provides a pH-activation mechanism. Chapter 2 presents the synthesis and spectroscopic characterization of a pH-responsive zinc(II) phthalocyanine tetramer, in which the phthalocyanine units

  15. Expression of neuronal and signaling proteins in penumbra around a photothrombotic infarction core in rat cerebral cortex.

    PubMed

    Demyanenko, S V; Panchenko, S N; Uzdensky, A B

    2015-06-01

    Photodynamic impact on animal cerebral cortex using water-soluble Bengal Rose as a photosensitizer, which does not cross the blood-brain barrier and remains in blood vessels, induces platelet aggregation, vessel occlusion, and brain tissue infarction. This reproduces ischemic stroke. Irreversible cell damage within the infarction core propagates to adjacent tissue and forms a transition zone - the penumbra. Tissue necrosis in the infarction core is too fast (minutes) to be prevented, but much slower penumbral injury (hours) can be limited. We studied the changes in morphology and protein expression profile in penumbra 1 h after local photothrombotic infarction induced by laser irradiation of the cerebral cortex after Bengal Rose administration. Morphological study using standard hematoxylin/eosin staining showed a 3-mm infarct core surrounded by 1.5-2.0 mm penumbra. Morphological changes in the penumbra were lesser and decreased towards its periphery. Antibody microarrays against 224 neuronal and signaling proteins were used for proteomic study. The observed upregulation of penumbra proteins involved in maintaining neurite integrity and guidance (NAV3, MAP1, CRMP2, PMP22); intercellular interactions (N-cadherin); synaptic transmission (glutamate decarboxylase, tryptophan hydroxylase, Munc-18-1, Munc-18-3, and synphilin-1); mitochondria quality control and mitophagy (PINK1 and Parkin); ubiquitin-mediated proteolysis and tissue clearance (UCHL1, PINK1, Parkin, synphilin-1); and signaling proteins (PKBα and ERK5) could be associated with tissue recovery. Downregulation of PKC, PKCβ1/2, and TDP-43 could also reduce tissue injury. These changes in expression of some neuronal proteins were directed mainly to protection and tissue recovery in the penumbra. Some upregulated proteins might serve as markers of protection processes in a penumbra.

  16. "Entitlement Means Prescription": Exploring the Rose Review

    ERIC Educational Resources Information Center

    Silcock, Peter

    2010-01-01

    The Rose Review makes a number of worthy recommendations deserving implementation, especially those advising a gradual, three-phase shift towards subject-based studies from play-based practices. But Rose's attempt to make the Primary Curriculum manageable does not and probably could not succeed. The content-led nature of a Rose-Reviewed…

  17. Acidolysis small molecular phenolic ether used as accelerator in photosensitive diazonaphthaquinone systems

    NASA Astrophysics Data System (ADS)

    Zhou, Haihua; Zou, Yingquan

    2006-03-01

    The photosensitive compounds in the photosensitive coatings of positive PS plates are the diazonaphthaquinone derivatives. Some acidolysis small molecular phenolic ethers, which were synthesized by some special polyhydroxyl phenols with vinyl ethyl ether, are added in the positive diazonaphthaquinone photosensitive composition to improve its sensitivity, composed with photo-acid-generators. The effects to the photosensitivity, anti-alkali property, anti-isopropyl alcohol property, dot resolution and line resolution of the coatings are studied with different additive percent of the special phenolic ethers. In the conventional photosensitive diazonaphthaquinone systems for positive PS plates, the photosensitivity is improved without negative effects to resolution, anti-alkali and anti-isopropyl alcohol properties when added about 5% of the special acidolysis phenolic ethers, EAAE or DPHE, composed with photo-acid-generators.

  18. An Evaluation of the ROSE System

    NASA Technical Reports Server (NTRS)

    Usher, John M.

    2002-01-01

    A request-oriented scheduling engine, better known as ROSE, is under development within the Flight Projects Directorate for the purpose of planning and scheduling of the activities and resources associated with the science experiments to be performed aboard the International Space Station (ISS). ROSE is being designed to incrementally process requests from payload developers (PDs) to model and schedule the execution of their science experiments on the ISS. The novelty of the approach comes from its web-based interface permitting the PDs to define their request via the construction of a graphical model to represent their requirements. Based on an examination of the current ROSE implementation, this paper proposes several recommendations for changes to the modeling component and makes mention of other potential applications of the ROSE system.

  19. In-vivo NMR studies of deuterium-labeled photosensitizers in mice tumor model

    NASA Astrophysics Data System (ADS)

    Ramaprasad, Subbaraya; Liu, Y. H.; Pandey, R. K.; Shiau, Fuu-Yau; Smith, Kevin M.

    1993-06-01

    Photodynamic therapy (PDT) has emerged as a promising modality for the treatment of cancer. We are using newly synthesized and chemically defined and characterized porphyrin photosensitizers that are specifically labeled with deuterium to perform in vivo NMR studies in a murine tumor model. In vivo magnetic resonance offers the potential for repetitive, safe, noninvasive evaluation of photosensitizers, tumor metabolism, and the effect of PDT on the tumor metabolism. In an effort to monitor noninvasively the photosensitizers in an in vivo tumor model, we are synthesizing several deuterium labeled photosensitizers which absorb red light at or above 630 nm. Development of methods to test these photosensitizers directly in humans is not feasible at this time, since these photosensitizers are new and we do not yet understand the side effects. In addition, we do not understand the potential benefits compared with Photofrin II, the widely used photosensitizer. To perform our in vivo deuterium NMR studies on mouse foot tumors, we have constructed a solenoid coil which operates at 30.7 MHz for the deuterium nucleus. We have been able to detect the deuterium labeled photosensitizer in the tumor after a direct intra-tumor injection. The use of 31P NMR to predict the possible outcome of PDT in these tumors is also discussed.

  20. Rose Scent

    PubMed Central

    Guterman, Inna; Shalit, Moshe; Menda, Naama; Piestun, Dan; Dafny-Yelin, Mery; Shalev, Gil; Bar, Einat; Davydov, Olga; Ovadis, Mariana; Emanuel, Michal; Wang, Jihong; Adam, Zach; Pichersky, Eran; Lewinsohn, Efraim; Zamir, Dani; Vainstein, Alexander; Weiss, David

    2002-01-01

    For centuries, rose has been the most important crop in the floriculture industry; its economic importance also lies in the use of its petals as a source of natural fragrances. Here, we used genomics approaches to identify novel scent-related genes, using rose flowers from tetraploid scented and nonscented cultivars. An annotated petal EST database of ∼2100 unique genes from both cultivars was created, and DNA chips were prepared and used for expression analyses of selected clones. Detailed chemical analysis of volatile composition in the two cultivars, together with the identification of secondary metabolism–related genes whose expression coincides with scent production, led to the discovery of several novel flower scent–related candidate genes. The function of some of these genes, including a germacrene D synthase, was biochemically determined using an Escherichia coli expression system. This work demonstrates the advantages of using the high-throughput approaches of genomics to detail traits of interest expressed in a cultivar-specific manner in nonmodel plants. PMID:12368489

  1. Primary Schooling in West Bengal

    ERIC Educational Resources Information Center

    Sen, Amartya

    2010-01-01

    With his Nobel Prize award money, Amartya Sen set up the Pratichi Trust which carries out research, advocacy and experimental projects in basic education, primary health care, and women's development in West Bengal and Bangladesh. Professor Sen himself took active interest in this work--helping set the agenda, looking at the evidence from…

  2. ROSE MIU Testing

    NASA Technical Reports Server (NTRS)

    Austin, Rebekah

    2015-01-01

    Overview of work done by Rebekah Austin during Pathways Internship work tour. Describes ROSE MIU (Reconfigurable Operational Spacecraft for Science and Exploration Module Interface Unit) features and test plan.

  3. Miocene denudation history of Himalaya deduced from IODP Exp. 354 Bengal Fan

    NASA Astrophysics Data System (ADS)

    Kohki, Y.; Cruz, J. W.; Osaki, A.; Manoj, M. C.; Hatano, N.; France-Lanord, C.; Spiess, V.; Klaus, A.

    2017-12-01

    The submarine Bengal Fan is the largest submarine fan on Earth and covers the whole Bay of Bengal. The sediments are fed by the Ganges and Brahmaputra rivers reflecting India-Asia plate collision. The sediments recovered from IODP Expedition 354 Bengal Fan record the uplift history of the Himalayan orogenic system. We examined the chemical composition of detrital garnets in the Miocene deposits from Site U1451, where drilling reached to basal horizon of the fan deposits, in order to reveal the detailed denudation history of Himalayan metamorphic rocks. For this purpose, the comparison of chemical composition between detrital garnet in the Bengal Fan deposits and metamorphic garnet in Himalayan metamorphic rocks was carried out. The chemical composition of the metamorphic garnet from Higher Himalayan Crystalline (HHC) in Karnali and Kaligandaki areas, western Nepal, was examined for chemical reference to detrital garnets in Bengal Fan. The metamorphic garnets in "Formation I (Le Fort, 1975)" in HHC are characterized by almandine-rich garnet with high pyrope content. Also, the garnets in "Formation II" are remarked by two types of garnets, i.e., almandine-rich and grandite-rich garnets. Meanwhile, the composition of garnets in "Formation III" is almandine-rich garnet with low pyrope content. In the Bengal Fan deposits, the characteristic garnets, which show the similarity to the metamorphic garnet in HHC, is not found from the Lower Miocene (Burdigalian) deposits. In the Middle and Upper Miocene deposits, the almandine-rich garnets characteristic in Formation I, are normally included. At the basal part of the Middle Miocene (Langhian), almandine-rich garnets with low pyrope content, suggesting the derivation from Formation III, are remarkable. The grandite-rich garnets from Formation II are sporadically found In the Upper Miocene deposits (Tortonian-Messinian). Above chemical comparison between the detrital garnets in Bengal Fan and metamorphic garnets from HHC

  4. Photosensitized oxidation of unsaturated polymers

    NASA Technical Reports Server (NTRS)

    Golub, M. A.

    1979-01-01

    The photosensitized oxidation or singlet oxygenation of unsaturated hydrocarbon polymers and of their model compounds was reviewed. Emphasis was on cis and trans forms of 1,4-polyisoprene, 1,4-polybutadiene and 1,2-poly(1,4-hexadiene), and on 1,4-poly(2,3-dimethyl-1,3-butadiene). The microstructural changes which occur in these polymers on reaction with O2-1 in solution were investigated by infrared H-1 and C-13 NMR spectroscopy. The polymers were shown to yield allylic hydroperoxides with shifted double bonds according to the ene mechanism established for simple olefins. The photosensitized oxidation of the above unsaturated polymer exhibited zero order kinetics, the relative rates paralleling the reactivities of the corresponding simple olefins towards O2-1.

  5. [Photosensitization and photoprotection by some drugs, metabolites and other compounds].

    PubMed

    Lozovskaia, E L; Makareeva, E N; Makedonov, I U

    1997-01-01

    Photosensitizing and photoprotecting efficiency of about a hundred of compounds, mainly drugs, was studied. The method based on chemiluminescence occurred along with photooxidation of glycyltryptophan under irradiation in UVB range in solution was used for testing. As a measure of photosensitizing efficiency the concentration of photosensitizer which induced two-fold increase of chemiluminescence intensity was chosen. The most effective photosensitizers are riboflavin, FAD, furagin, psoralene, vicasol, benzobarbital, mydocalm, angelicyn, furadonin, ethacridin, diazolin, folic acid. With regard to pharmacological doses of drugs in organism more dangerous sensitizers (in descending order) are p-aminosalicylic acid, furagin, riboflavin, benzobarbital, thiopental, chloramphenicol, nicodin, mydocalm, furadonin, oxolonic acid, furazolidone, psoralene, nicotinamide and diazolin. Photoprotecting effect was described by the concentration at which chemiluminescence intensity decreased twice. The most effective photoprotectors are etamsilat, quercetin, ftivazid, chlorpromazine, diprazine, thioridazine, aminophenazone, oxaphenamide. Concentration dependence for some of these drugs (etamsilat, chlorpromazine, diprazine, thioridazine) is non-monotonous: they inhibit photooxidation in low concentration (about 10(-7)-10(-6) M), but at higher concentrations (10(-5)-10(-4) M) photosensitization dominates over photoprotection.

  6. Bay of Bengal Surface and Thermocline and the Arabian Sea

    DTIC Science & Technology

    2015-09-30

    oceanographic processes that exchange low salinity surface and upper thermocline water of the Bay of Bengal with the salty Arabian Sea and tropical Indian Ocean ...two northern embayments of the Indian Ocean . OBJECTIVES Two northern Indian Ocean embayments, the Arabian Sea and the Bay of Bengal, are so close...e.g. where do the eddies come from? 2. Investigating advective pathways, and the role of isopycnal mixing, exchanging upper ocean water between the

  7. Origin and fate of sedimentary organic matter in the northern Bay of Bengal during the last 18 ka

    NASA Astrophysics Data System (ADS)

    Contreras-Rosales, L. A.; Schefuß, E.; Meyer, V.; Palamenghi, L.; Lückge, A.; Jennerjahn, T. C.

    2016-11-01

    The Northern Bay of Bengal (NBoB) is a globally important region for deep-sea organic matter (OM) deposition due to massive fluvial discharge from the Ganges-Brahmaputra-Meghna (G-B-M) rivers and moderate to high surface productivity. Previous studies have focused on carbon burial in turbiditic sediments of the Bengal Fan. However, little is known about the storage of carbon in pelagic and hemipelagic sediments of the Bay of Bengal over millennial time scales. This study presents a comprehensive history of OM origin and fate as well as a quantification of carbon sediment storage in the Eastern Bengal Slope (EBS) during the last 18 ka. Bulk organic proxies (TOC, TIC, TN, δ13CTOC, δ15NTN) and content and composition of total hydrolysable amino acids (THAA) in a sediment core (SO188-342KL) from the EBS were analyzed. Three periods of high OM accumulation were identified: the Late Glacial (LG), the Bölling/Alleröd (B/A), and the Early Holocene Climatic Optimum (EHCO). Lower eustatic sea level before 15 ka BP allowed a closer connection between the EBS and the fluvial debouch, favoring high terrestrial OM input to the core site. This connection was progressively lost between 15 and 7 ka BP as sea level rose to its present height and terrestrial OM input decreased considerably. Export and preservation of marine OM was stimulated during periods of summer monsoon intensification (B/A and EHCO) as a consequence of higher surface productivity enhanced by cyclonic-eddy nutrient pumping and fluvial nutrient delivery into the photic zone. Changes in the THAA composition indicate that the marine plankton community structure shifted from calcareous-dominated before 13 ka BP to siliceous-dominated afterwards. They also indicate that the relative proportion of marine versus terrestrial OM deposited at site 342KL was primarily driven by relative sea level and enlarged during the Holocene. The ballasting effect of lithogenic particles during periods of high coastal proximity and

  8. Development and testing of monoclonal antibody-based rapid immunodiagnostic test kits for direct detection of Vibrio cholerae O139 synonym Bengal.

    PubMed

    Hasan, J A; Huq, A; Nair, G B; Garg, S; Mukhopadhyay, A K; Loomis, L; Bernstein, D; Colwell, R R

    1995-11-01

    We report on the development and testing of two monoclonal antibody-based rapid immunodiagnostic test kits, BengalScreen, a coagglutination test, and Bengal DFA, a direct fluorescent-antibody test, for direct detection of Vibrio cholerae O139 synonym Bengal in clinical and environmental specimens. The BengalScreen test requires less than 5 min to complete and can be used in the field. Bengal DFA, being more sensitive than BengalScreen, requires only one reagent and less than 20 min for detection and enumeration of V. cholerae O139 synonym Bengal. In tests for specificity, all 40 strains of V. cholerae O139 reacted with both test kits, whereas 157 strains of heterologous species examined did not, yielding 100% specificity in this study. A field trial was conducted in with both BengalScreen and Bengal DFA, and the results were compared with those obtained by conventional culture methods. BengalScreen demonstrated a sensitivity of 95%, a specificity of 100%, a positive predictive value of 100%, and a negative predictive value of 94%. Results obtained by Bengal DFA, on the other hand, were 100% sensitive and 100% specific and yielded 100% positive and negative predictive values compared with culture methods. In a second evaluation, 93 stool specimens from Mexico that were negative for V. cholerae O139 by culture were also tested with both the BengalScreen and Bengal DFA kits. None of the 93 specimens were positive for V. cholerae O139 by both tests. A concentration method was optimized for screening of environmental water samples for V. cholerae O139 synonym Bengal with rapid test kits. BengalScreen results were unequivocally positive when water samples contained at least 2.0 x 10(3) CFU/ml, whereas Bengal DFA demonstrated an unequivocally positive reaction when the water sample contained at least 1.5 x 10(2) CFU/ml. When Bengal DFA was compared with conventional culture methods for enumeration of V. cholerae O139 synonym Bengal organisms, no difference was observed.

  9. The phototoxicity of phenothiazinium-based photosensitizers to bacterial membranes.

    PubMed

    Hussain, Saimah; Harris, Frederick; Phoenix, David A

    2006-02-01

    The ability of phenothiazinium-based photosensitizers to induce photodamage to Escherichia coli membranes is investigated. Phenothiazinium-based photosensitizers were found to be somewhat lipophilic (log P>0.7) and to induce surface-pressure changes (3-12 mN m(-1)) in lipid monolayers mimetic of bacterial membranes, implying that these molecules are able to penetrate biological membranes. Under dark and light conditions (3.15 J cm(-1) for 30 min), phenothiazinium-based photosensitizers were incubated with E. coli cells. These cells showed levels of dark bacteriolysis that ranged between 6% and 13%, with light conditions leading to no significant increase in these levels. Gas chromatography-based analyses showed such incubations to produce no significant changes in the levels of C(16) and C(18) fatty acid chain saturation found in E. coli whole lipid-extracts. It is concluded that the phenothiazinium-based photosensitizers studied may not use E. coli membranes as their primary photodynamic target, but may inflict photodamage on cytoplasmic targets, possibly DNA.

  10. Photosensitizer-Embedded Polyacrylonitrile Nanofibers as Antimicrobial Non-Woven Textile

    PubMed Central

    Stanley, Sarah L.; Scholle, Frank; Zhu, Jiadeng; Lu, Yao; Zhang, Xiangwu; Situ, Xingci; Ghiladi, Reza A.

    2016-01-01

    Toward the objective of developing platform technologies for anti-infective materials based upon photodynamic inactivation, we employed electrospinning to prepare a non-woven textile comprised of polyacrylonitrile nanofibers embedded with a porphyrin-based cationic photosensitizer; termed PAN-Por(+). Photosensitizer loading was determined to be 34.8 nmol/mg material; with thermostability to 300 °C. Antibacterial efficacy was evaluated against four bacteria belonging to the ESKAPE family of pathogens (Staphylococcus aureus; vancomycin-resistant Enterococcus faecium; Acinetobacter baumannii; and Klebsiella pneumonia), as well as Escherichia coli. Our results demonstrated broad photodynamic inactivation of all bacterial strains studied upon illumination (30 min; 65 ± 5 mW/cm2; 400–700 nm) by a minimum of 99.9996+% (5.8 log units) regardless of taxonomic classification. PAN-Por(+) also inactivated human adenovirus-5 (~99.8% reduction in PFU/mL) and vesicular stomatitis virus (>7 log units reduction in PFU/mL). When compared to cellulose-based materials employing this same photosensitizer; the higher levels of photodynamic inactivation achieved here with PAN-Por(+) are likely due to the combined effects of higher photosensitizer loading and a greater surface area imparted by the use of nanofibers. These results demonstrate the potential of photosensitizer-embedded polyacrylonitrile nanofibers to serve as scalable scaffolds for anti-infective or self-sterilizing materials against both bacteria and viruses when employing a photodynamic inactivation mode of action. PMID:28335205

  11. Rose parental characterization and population development for the identification of novel rose black spot resistance genes [abstract

    USDA-ARS?s Scientific Manuscript database

    Rose black spot disease, caused by the pathogen Diplocarpon rosae Wolf, is one of the most widespread and serious diseases of outdoor-grown roses worldwide. Defoliation caused by the disease compromises ornamental value, and repeated defoliation events weakens plants and can lead to plant death. Bot...

  12. Evaluation of different photosensitizers for use in photochemical gene transfection.

    PubMed

    Prasmickaite, L; Høgset, A; Berg, K

    2001-04-01

    Many potentially therapeutic macromolecules, e.g. transgenes used in gene therapy, are taken into the cells by endocytosis, and have to be liberated from endocytic vesicles in order to express a therapeutic function. To achieve this we have developed a new technology, named photochemical internalization (PCI), based on photochemical reactions inducing rupture of endocytic vesicles. The aim of this study was to clarify which properties of photosensitizers are important for obtaining the PCI effect improving gene transfection. The photochemical effect on transfection of human melanoma THX cells has been studied employing photosensitizers with different physicochemical properties and using two gene delivery vectors: the cationic polypeptide polylysine and the cationic lipid 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP). Photochemical treatment by photosensitizers that do not localize in endocytic vesicles (tetra[3-hydroxyphenyl]porphyrin and 5-aminolevulinic acid-induced protoporphyrin IX) do not stimulate transfection, irrespective of the gene delivery vector. In contrast, photosensitizers localized in endocytic vesicles stimulate polylysine-mediated transfection, and amphiphilic photosensitizers (disulfonated aluminium phthalocyanine [AlPcS2a] and meso-tetraphenylporphynes) show the strongest positive effect, inducing approximately 10-fold increase in transfection efficiency. In contrast, DOTAP-mediated transfection is inhibited by all photochemical treatments irrespective of the photosensitizer used. Neither AlPcS2a nor Photofrin affects the uptake of the transfecting DNA over the plasma membrane, therefore photochemical permeabilization of endocytic vesicles seems to be the most likely mechanism responsible for the positive PCI effect on gene transfection.

  13. In vitro lethal photosensitization of S. mutans using methylene blue and toluidine blue O as photosensitizers.

    PubMed

    Araújo, Patrícia V; Teixeira, Karina I R; Lanza, Lincoln D; Cortes, Maria E; Poletto, Luiz T A

    2009-01-01

    The purpose of this in vitro study was to evaluate the antimicrobial effect of photodynamic therapy on Streptococcus mutans (A TCC 25175) suspensions, using a red laser for one minute in combination with toluidine blue O (TBO) or methylene blue (MB). Both photosensitizers were used in three concentrations (25, 10 and 5 mg/L). The activity ofphotosensitizers and laser irradiation were tested separately on the bacteria, as well as the irradiation of this light source in the presence of the TBO or MB. These groups were compared to a control group, in which the microorganism did not receive any treatment. The activity of both TBO and MB or laser irradiation, alone, were not able to reduce the number of S. mutans. In the groups of lethal photosensitization, a bacterial reduction of 70% for TBO and 73% for MB was observed when these photosensitizers were used at 25 mg/L and a reduction of 48% was observed for MB at 5mg/L. In other concentrations there were no significant differences in comparison to the control group. Both the TBO and the MB at 25 mg/L associated with a red laser had an excellent potential for use in PDT in lethal sensitization of S. mutans.

  14. A novel automated instrument designed to determine photosensitivity thresholds (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Aguilar, Mariela C.; Gonzalez, Alex; Rowaan, Cornelis; De Freitas, Carolina; Rosa, Potyra R.; Alawa, Karam; Lam, Byron L.; Parel, Jean-Marie A.

    2016-03-01

    As there is no clinically available instrument to systematically and reliably determine the photosensitivity thresholds of patients with dry eyes, blepharospasms, migraines, traumatic brain injuries, and genetic disorders such as Achromatopsia, retinitis pigmentosa and other retinal dysfunctions, a computer-controlled optoelectronics system was designed. The BPEI Photosensitivity System provides a light stimuli emitted from a bi-cupola concave, 210 white LED array with varying intensity ranging from 1 to 32,000 lux. The system can either utilize a normal or an enhanced testing mode for subjects with low light tolerance. The automated instrument adjusts the intensity of each light stimulus. The subject is instructed to indicate discomfort by pressing a hand-held button. Reliability of the responses is tracked during the test. The photosensitivity threshold is then calculated after 10 response reversals. In a preliminary study, we demonstrated that subjects suffering from Achromatopsia experienced lower photosensitivity thresholds than normal subjects. Hence, the system can safely and reliably determine the photosensitivity thresholds of healthy and light sensitive subjects by detecting and quantifying the individual differences. Future studies will be performed with this system to determine the photosensitivity threshold differences between normal subjects and subjects suffering from other conditions that affect light sensitivity.

  15. Godavari River Delta Panorama, Bay of Bengal, India

    NASA Image and Video Library

    1993-01-19

    STS054-80-024 (13-19 Jan 1993) --- As the Shuttle was passing southeast over the coast of India, approaching the Bay of Bengal, Endeavour's crew took this picture of the Godavari River Delta. The sun glint pattern was centered directly over the delta and highlighted well the intricate drainage pattern. Offshore, water features associated with current boundaries and river plumes are readily visible. The line of clouds along the coast south of the delta suggest that surface winds are blowing onshore from the Bay of Bengal. As the air passes over the warmer coastal water and land, it is warmed and begins to rise. The moisture in the air condenses, forming a line of low-level clouds.

  16. Solid state photosensitive devices which employ isolated photosynthetic complexes

    DOEpatents

    Peumans, Peter; Forrest, Stephen R.

    2009-09-22

    Solid state photosensitive devices including photovoltaic devices are provided which comprise a first electrode and a second electrode in superposed relation; and at least one isolated Light Harvesting Complex (LHC) between the electrodes. Preferred photosensitive devices comprise an electron transport layer formed of a first photoconductive organic semiconductor material, adjacent to the LHC, disposed between the first electrode and the LHC; and a hole transport layer formed of a second photoconductive organic semiconductor material, adjacent to the LHC, disposed between the second electrode and the LHC. Solid state photosensitive devices of the present invention may comprise at least one additional layer of photoconductive organic semiconductor material disposed between the first electrode and the electron transport layer; and at least one additional layer of photoconductive organic semiconductor material, disposed between the second electrode and the hole transport layer. Methods of generating photocurrent are provided which comprise exposing a photovoltaic device of the present invention to light. Electronic devices are provided which comprise a solid state photosensitive device of the present invention.

  17. Computational Study of Oxidation of Guanine by Singlet Oxygen (1 Δg ) and Formation of Guanine:Lysine Cross-Links.

    PubMed

    Thapa, Bishnu; Munk, Barbara H; Burrows, Cynthia J; Schlegel, H Bernhard

    2017-04-27

    Oxidation of guanine in the presence of lysine can lead to guanine-lysine cross-links. The ratio of the C4, C5 and C8 crosslinks depends on the manner of oxidation. Type II photosensitizers such as Rose Bengal and methylene blue can generate singlet oxygen, which leads to a different ratio of products than oxidation by type I photosensitizers or by one electron oxidants. Modeling reactions of singlet oxygen can be quite challenging. Reactions have been explored using CASSCF, NEVPT2, DFT, CCSD(T), and BD(T) calculations with SMD implicit solvation. The spin contamination in open-shell calculations were corrected by Yamaguchi's approximate spin projection method. The addition of singlet oxygen to guanine to form guanine endo- peroxide proceeds step-wise via a zwitterionic peroxyl intermediate. The subsequent barrier for ring closure is smaller than the initial barrier for singlet oxygen addition. Ring opening of the endoperoxide by protonation at C4-O is followed by loss of a proton from C8 and dehydration to produce 8-oxoG ox . The addition of lysine (modelled by methylamine) or water across the C5=N7 double bond of 8-oxoG ox is followed by acyl migration to form the final spiro products. The barrier for methylamine addition is significantly lower than for water addition and should be the dominant reaction channel. These results are in good agreement with the experimental results for the formation of guanine-lysine cross-links by oxidation by type II photosensitizers. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Adapting BODIPYs to singlet oxygen production on silica nanoparticles.

    PubMed

    Epelde-Elezcano, Nerea; Prieto-Montero, Ruth; Martínez-Martínez, Virginia; Ortiz, María J; Prieto-Castañeda, Alejandro; Peña-Cabrera, Eduardo; Belmonte-Vázquez, José L; López-Arbeloa, Iñigo; Brown, Ross; Lacombe, Sylvie

    2017-05-31

    A modified Stöber method is used to synthesize spherical core-shell silica nanoparticles (NPs) with an external surface functionalized by amino groups and with an average size around 50 nm. Fluorescent dyes and photosensitizers of singlet oxygen were fixed, either separately or conjointly, respectively in the core or in the shell. Rhodamines were encapsulated in the core with relatively high fluorescence quantum yields (Φ fl ≥ 0.3), allowing fluorescence tracking of the particles. Various photosensitizers of singlet oxygen (PS) were covalenty coupled to the shell, allowing singlet oxygen production. The stability of NP suspensions strongly deteriorated upon grafting the PS, affecting their apparent singlet oxygen quantum yields. Agglomeration of NPs depends both on the type and on the amount of grafted photosensitizer. New, lab-made, halogenated 4,4-difluoro-4-bora-3a,4a-diaza-s-indacenes (BODIPY) grafted to the NPs achieved higher singlet oxygen quantum yields (Φ Δ ∼ 0.35-0.40) than Rose Bengal (RB) grafted NPs (Φ Δ ∼ 0.10-0.27). Finally, we combined both fluorescence and PS functions in the same NP, namely a rhodamine in the silica core and a BODIPY or RB grafted in the shell, achieving the performance Φ fl ∼ 0.10-0.20, Φ Δ ∼ 0.16-0.25 with a single excitation wavelength. Thus, proper choice of the dyes, of their concentrations inside and on the NPs and the grafting method enables fine-tuning of singlet oxygen production and fluorescence emission.

  19. Monotonic trends in spatio-temporal distribution and concentration of monsoon precipitation (1901-2002), West Bengal, India

    NASA Astrophysics Data System (ADS)

    Chatterjee, Soumendu; Khan, Ansar; Akbari, Hashem; Wang, Yupeng

    2016-12-01

    This paper intended to investigate spatio-temporal monotonic trend and shift in concentration of monsoon precipitation across West Bengal, India, by analysing the time series of monthly precipitation from 18 weather stations during the period from 1901 to 2002. In dealing with, the inhomogeneity in the precipitation series, RHtestsV4 software package is used to detect, and adjust for, multiple change points (shifts) that could exist in data series. Finally, the cumulative deviation test was applied at 5% significant level to check the homogeneity (presence of historic changes by cumulative deviations test). Afterward, non-parametric Mann-Kendall (MK) test and Theil-Sen estimator (TSE) was applied to detect of nature and slope of trends; and, Sequential Mann Kendall (SQMK) test was applied for detection of turning point and magnitude of change in trends. Prior to the application of statistical tests, the pre-whitening technique was used to eliminate the effect of autocorrelation in precipitation data series. Four indices- precipitation concentration index (PCI), precipitation concentration degree (PCD), precipitation concentration period (PCP) and fulcrum (centre of gravity) were used to detect precipitation concentration and the spatial pattern in it. The application of the above-mentioned procedures has shown very notable statewide monotonic trend for monsoon precipitation time series. Regional cluster analysis by SQMK found increasing precipitation in mountain and coastal regions in general, except during the non- monsoon seasons. The results show that higher PCI values were mainly observed in South Bengal, whereas lower PCI values were mostly detected in North Bengal. The PCI values are noticeably larger in places where both monsoon total precipitation and span of rainy season are lower. The results of PCP reveal that precipitation in Gangetic Bengal mostly occurs in summer (monsoon season), and the rainy season arrives earlier in North Bengal than South Bengal

  20. Exploration of photosensitive polyimide as the modification layer in thin film microcircuit

    NASA Astrophysics Data System (ADS)

    Liu, Lily; Song, Changbin; Xue, Bin; Li, Jing; Wang, Junxi; Li, Jinmin

    2018-02-01

    Positive type photosensitive polyimide is used as the modification layer in the thin film transistors production process. The photosensitive polyimide is not only used as the second insulating layer, it can also be used instead of a mask because of the photosensitivity. A suitable curing condition can help photosensitive polyimide form the high performance polyimide with orderly texture inside, and the performance of imidization depends on the precise control of temperature, time, and heat control during the curing process. Therefore, experiments of different stepped up heating tests are made, and the ability of protecting silicon dioxide is analyzed.

  1. Fluorescent proteins as singlet oxygen photosensitizers: mechanistic studies in photodynamic inactivation of bacteria

    NASA Astrophysics Data System (ADS)

    Ruiz-González, Rubén.; White, John H.; Cortajarena, Aitziber L.; Agut, Montserrat; Nonell, Santi; Flors, Cristina

    2013-02-01

    Antimicrobial photodynamic therapy (aPDT) combines a photosensitizer, light and oxygen to produce reactive oxygen species (ROS), mainly singlet oxygen (1O2), to photo-oxidize important biomolecules and induce cell death. aPDT is a promising alternative to standard antimicrobial strategies, but its mechanisms of action are not well understood. One of the reasons for that is the lack of control of the photosensitizing drugs location. Here we report the use of geneticallyencoded fluorescent proteins that are also 1O2 photosensitizers to address the latter issue. First, we have chosen the red fluorescent protein TagRFP as a photosensitizer, which unlike other fluorescent proteins such as KillerRed, is able to produce 1O2 but not other ROS. TagRFP photosensitizes 1O2 with a small, but not negligible, quantum yield. In addition, we have used miniSOG, a more efficient 1O2 photosensitizing fluorescent flavoprotein that has been recently engineered from phototropin 2. We have genetically incorporated these two photosensitizers into the cytosol of E. coli and demonstrated that intracellular 1O2 is sufficient to kill bacteria. Additional assays have provided further insight into the mechanism of cell death. Photodamage seems to occur primarily in the inner membrane, and extends to the outer membrane if the photosensitizer's efficiency is high enough. These observations are markedly different to those reported for external photosensitizers, suggesting that the site where 1O2 is primarily generated proves crucial for inflicting different types of cell damage.

  2. Vertical Structure of Aerosols and Mineral Dust Over the Bay of Bengal From Multisatellite Observations

    NASA Astrophysics Data System (ADS)

    Lakshmi, N. B.; Nair, Vijayakumar S.; Suresh Babu, S.

    2017-12-01

    The vertical distribution of aerosol and dust extinction coefficient over the Bay of Bengal is examined using the satellite observations (Cloud Aerosol Lidar with Orthogonal Polarization (CALIOP) and Moderate Resolution Imaging Spectroradiometer (MODIS)) for the period from 2006 to 2017. Distinct seasonal pattern is observed in the vertical structure of both aerosol and dust over the Bay of Bengal with an enhancement of 24% in the aerosol extinction above 1 km from winter (December, January and February) to premonsoon (March, April, and May). Significant contribution of dust is observed over the northern Bay of Bengal during premonsoon season where 22% of the total aerosol extinction is contributed by dust aerosols transported from the nearby continental regions. During winter, dust transport is found to be less significant with fractional contribution of 10%-13% to the total aerosol optical depth over the Bay of Bengal. MODIS-derived dust fraction (fine mode based) shows an overestimation up to twofold compared to CALIOP dust fraction (depolarization based), whereas the Goddard Chemistry Aerosol Radiation and Transport-simulated dust fraction underestimates the satellite-derived dust fractions over the Bay of Bengal. Though the long-term variation in dust aerosol showed a decreasing trend over the Bay of Bengal, the confidence level is insufficient in establishing the robustness of the observed trend. However, significant dust-induced heating is observed above the boundary layer during premonsoon season. This dust-induced elevated heating can affect the convection over the Bay of Bengal which will have implication on the monsoon dynamics over the Indian region.

  3. Rose's Life Lessons: Signed and Spoken

    ERIC Educational Resources Information Center

    McAuliffe, Chris

    2008-01-01

    In this article, the author shares the experiences of his wife, Cheryl, and his 5-year-old daughter, Rose, when they visited their local high school's child development class. Cheryl and Rose met with over a 100 teenagers teenagers in eight different classes to talk about their family, raising a child with Down syndrome, and their experiences with…

  4. Status of women in two Bengals: evidence from large scale surveys.

    PubMed

    Chattopadhyay, Aparajita; Goswami, Baishali

    2007-03-01

    Greater female autonomy is mirrored through better performance in the major demographic and social indicators. This study attempts to capture the effect of religion on the status of women considering 'Greater Bengal'. There is much evidence suggesting that when cultural factors are constant, religion does not have a significant effect on any demographic issue. In this paper, the validity of this proposition is examined using two datasets, namely NFHS II (98-99) and BDHS 2000. It is clear from the analyses that not only region but also religion has a distinct effect on the status of women. In West Bengal, the religious gap for all the indicators considered is pretty high, whereas in Bangladesh the gap is not that wide. A state-level population policy is needed in West Bengal to act as a social leveller.

  5. Photosensitized Chemically Amplified Resist (PSCAR) 2.0 for high-throughput and high-resolution EUV lithography: dual photosensitization of acid generation and quencher decomposition by flood exposure

    NASA Astrophysics Data System (ADS)

    Nagahara, Seiji; Carcasi, Michael; Shiraishi, Gosuke; Nakagawa, Hisashi; Dei, Satoshi; Shiozawa, Takahiro; Nafus, Kathleen; De Simone, Danilo; Vandenberghe, Geert; Stock, Hans-Jürgen; Küchler, Bernd; Hori, Masafumi; Naruoka, Takehiko; Nagai, Tomoki; Minekawa, Yukie; Iseki, Tomohiro; Kondo, Yoshihiro; Yoshihara, Kosuke; Kamei, Yuya; Tomono, Masaru; Shimada, Ryo; Biesemans, Serge; Nakashima, Hideo; Foubert, Philippe; Buitrago, Elizabeth; Vockenhuber, Michaela; Ekinci, Yasin; Oshima, Akihiro; Tagawa, Seiichi

    2017-03-01

    A new type of Photosensitized Chemically Amplified Resist (PSCAR) **: "PSCAR 2.0," is introduced in this paper. PSCAR 2.0 is composed of a protected polymer, a "photo acid generator which can be photosensitized" (PS-PAG), a "photo decomposable base (quencher) which can be photosensitized" (PS-PDB) and a photosensitizer precursor (PP). With this PSCAR 2.0, a photosensitizer (PS) is generated by an extreme ultra-violet (EUV) pattern exposure. Then, during a subsequent flood exposure, PS selectively photosensitizes the EUV exposed areas by the decomposition of a PS-PDB in addition to the decomposition of PS-PAG. As these pattern-exposed areas have the additional acid and reduced quencher concentration, the initial quencher loading in PSCAR 2.0 can be increased in order to get the same target critical dimensions (CD). The quencher loading is to be optimized simultaneously with a UV flood exposure dose to achieve the best lithographic performance and resolution. In this work, the PSCAR performance when different quenchers are used is examined by simulation and exposure experiments with the 16 nm half-pitch (HP) line/space (L/S, 1:1) patterns. According to our simulation results among resists with the different quencher types, the best performance was achieved by PSCAR 2.0 using PS-PDB with the highest possible chemical gradient resulting in the lowest line width roughness (LWR). PSCAR 2.0 performance has furthermore been confirmed on ASML's NXE:3300 with TEL's standalone pre-alpha flood exposure tool at imec. The initial PSCAR 2.0 patterning results on NXE:3300 showed the accelerated photosensitization performance with PS-PDB. From these results, we concluded that the dual sensitization of PS-PAG and PS-PDB in PSCAR 2.0 have a potential to realize a significantly improved resist performance in EUV lithography.

  6. Development of photosensitive silsesquioxane

    NASA Astrophysics Data System (ADS)

    Tashiro, Yuji; Sekito, Takeshi; Iwata, Takafumi; Yokoyama, Daishi; Nonaka, Toshiaki

    2008-11-01

    We succeeded in development of SOG materials comprised of cage-type phenyl silsesquioxanes (PSQ) and their alkali soluble derivatives. The alkali soluble silsesquioxane (APSQ) can provide both positive and negative tone photosensitive SOG combination with diazo naphtoquinone (DNQ) and photo-base (acid) agent, respectively. Here we present feature of photolithography process and film properties for our SOG materials.

  7. DFT application for chlorin derivatives photosensitizer drugs modeling

    NASA Astrophysics Data System (ADS)

    Machado, Neila; Carvalho, B. G.; Téllez Soto, C. A.; Martin, A. A.; Favero, P. P.

    2018-04-01

    Photodynamic therapy is an alternative form of cancer treatment that meets the desire for a less aggressive approach to the body. It is based on the interaction between a photosensitizer, activating light, and molecular oxygen. This interaction results in a cascade of reactions that leads to localized cell death. Many studies have been conducted to discover an ideal photosensitizer, which aggregates all the desirable characteristics of a potent cell killer and generates minimal side effects. Using Density Functional Theory (DFT) implemented in the program Vienna Ab-initio Simulation Package, new chlorin derivatives with different functional groups were simulated to evaluate the different absorption wavelengths to permit resonant absorption with the incident laser. Gaussian 09 program was used to determine vibrational wave numbers and Natural Bond Orbitals. The chosen drug with the best characteristics for the photosensitizer was a modified model of the original chlorin, which was called as Thiol chlorin. According to our calculations it is stable and is 19.6% more efficient at optical absorption in 708 nm in comparison to the conventional chlorin e6. Vibrational modes, optical and electronic properties were predicted. In conclusion, this study is an attempt to improve the development of new photosensitizer drugs through computational methods that save time and contribute to decrease the numbers of animals for model application.

  8. Sunlight-Dependent Hydrogen Production by Photosensitizer/Hydrogenase Systems.

    PubMed

    Adam, David; Bösche, Lisa; Castañeda-Losada, Leonardo; Winkler, Martin; Apfel, Ulf-Peter; Happe, Thomas

    2017-03-09

    We report a sustainable in vitro system for enzyme-based photohydrogen production. The [FeFe]-hydrogenase HydA1 from Chlamydomonas reinhardtii was tested for photohydrogen production as a proton-reducing catalyst in combination with eight different photosensitizers. Using the organic dye 5-carboxyeosin as a photosensitizer and plant-type ferredoxin PetF as an electron mediator, HydA1 achieves the highest light-driven turnover number (TON HydA1 ) yet reported for an enzyme-based in vitro system (2.9×10 6  mol(H 2 ) mol(cat) -1 ) and a maximum turnover frequency (TOF HydA1 ) of 550 mol(H 2 ) mol(HydA1) -1  s -1 . The system is fueled very effectively by ambient daylight and can be further simplified by using 5-carboxyeosin and HydA1 as a two-component photosensitizer/biocatalyst system without an additional redox mediator. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Overnight Scentsation Rose Plant

    NASA Technical Reports Server (NTRS)

    1998-01-01

    International Flavors and Fragrances Inc., Dr. Braja Mookherjee with the Overnight Scentsation rose plant after its flight aboard NASA's shuttle mission STS-95 for experimentation on scent in microgravity.

  10. Anchoring energy of photo-sensitive polyimide alignment film containing methoxy cinnamate

    NASA Astrophysics Data System (ADS)

    Kim, Suyoung; Shin, Sung Eui; Shin, DongMyung

    2010-02-01

    Photosensitive polyimide containing 2-methoxy cinnamate was synthesized for photo-alignment layer of liquid crystals (LCs). 2-Methoxy cinnamic acid was confirmed photo-sensitive material by linearly polarized UV light. We studied that effect of polarized UV light on rubbed polyimide film. Anchoring energy of liquid crystal with aligning surface was measured. Irradiation of depolarized UV light on rubbed Polyimide film suppressed effective anchoring energy. Linearly polarized UV light on rubbed polyimide film controlled anchoring energy effectively. Polyimide film containing 2-methoxy cinnamate can control the photo-alignment layer easily due to its photo-sensitivity.

  11. FURTHER STUDIES ON THE INHIBITION OF CYPRIDINA LUMINESCENCE BY LIGHT, WITH SOME OBSERVATIONS ON METHYLENE BLUE

    PubMed Central

    Harvey, E. Newton

    1926-01-01

    1. Eosin, erythrosin, rose bengale, cyanosin, acridine, and methylene blue act photodynamically on the luminescence of a Cypridina luciferin-luciferase solution. In presence of these dyes inhibition of luminescence, which without the dye occurs only in blue-violet light, takes place in green, yellow, orange, or red light, depending on the position of the absorption bands of the dye. 2. Inhibition of Cypridina luminescence without photosensitive dye in blue-violet light, or with photosensitive dye in longer wave-lengths, does not occur in absence of oxygen. Light acts by accelerating the oxidation of luciferin without luminescence. Eosin or methylene blue act by making longer wave-lengths effective, but there is no evidence that these dyes become reduced in the process. 3. The luciferin-oxyluciferin system is similar to the methylene white-methylene blue system in many ways but not exactly similar in respect to photochemical change. Oxidation of the dye is favored in acid solution, reduction in alkaline solution. However, oxidation of luciferin is favored in all pH ranges from 4 to 10 but is much more rapid in alkaline solution, either in light or darkness. There is no evidence that reduction of oxyluciferin is favored in alkaline solution. Clark's observation that oxidation (blueing) of methylene white occurs in complete absence of oxygen has been confirmed for acid solutions. I observed no blueing in light in alkaline solution. PMID:19872301

  12. Population genetic study in ten endogamous groups of West Bengal, India.

    PubMed

    Mukherjee, B N; Walter, H; Malhotra, K C; Chakraborty, R; Sauber, P; Banerjee, S; Roy, M

    1987-09-01

    Ten endogamous population groups of West Bengal (India)--Rabhas, Garos, Mechs, Rajbanshis, Jalia Kaibartas, Bagdis, Lodhas, Mundas, Brahmins, Vaidyas--have been typed for twelve polymorphic systems: ABO, Gm, Km, Hp, Cp, Tf, Alb, Hb, aP, EsD, AK and PGM1. The results are compared with those obtained on other Indian populations. Serological and anthropometric data, which have been included into population comparisons, reveal a considerable genetic variability of the groups under study. This variability is obviously connected with the population history of West Bengal.

  13. Amy Rose | NREL

    Science.gov Websites

    Rose is a member of the Markets & Policy Analysis Group in the Strategic Energy Analysis Center integration of renewable energy Research Interests Energy policy and regulation Decision support tools to inform power sector policy and regulatory decisions Energy and development International energy policy

  14. Laser inactivation of periodontal bacteria using photosensitizing dyes

    NASA Astrophysics Data System (ADS)

    Golding, Paul S.; Maddocks, L.; King, Terence A.; Drucker, D. B.

    1996-12-01

    We demonstrate the killing of the oral bacteria Prevotella nigrescens using a photosensitizer and light from a 10 Hz, frequency doubled, Q-switched Nd:YAG pumped dye laser, with modified oscillator to increase output power. This system produced light at wavelengths close to 620 nm, the absorption maximum of the photosensitizing agent, malachite green isothiocyanate, a wavelength that is not significantly absorbed by tissue. A bacterial reduction of 97.5 percent was achieved at an energy density of 0.67 J/cm2 and exposure times of 300 seconds.

  15. Novel approach to the microbial decontamination of strawberries: chlorophyllin-based photosensitization.

    PubMed

    Luksiene, Z; Paskeviciute, E

    2011-05-01

    This study is focused on the possibility to control microbial contamination of strawberries by chlorophyllin (Na-Chl)-based photosensitization. Moreover, photosensitization-induced effects on key quality attributes of treated strawberries was evaluated.   Strawberries were inoculated with Listeria monocytogenes ATC(L3) C 7644, soaked in 1mmol l(-1) Na-Chl for 5 min and illuminated for 30 min with visible light (λ = 400 nm, energy density 12 mW cm(-2) ). Results indicated that the decontamination of strawberries using photosensitization was 98% compared to control sample. Naturally occurring yeasts/microfungi and mesophiles were inhibited by 86 and 97%, respectively. The shelf life of treated strawberries was extended by 2 days. The total antioxidant activity of treated strawberries increased by 19%. No impact on the amount of phenols, anthocyanins or surface colour was detected.   Photosensitization may be an effective, nonthermal and environmentally friendly microbial decontamination technique which expands the shelf life of strawberries without any negative impact on antioxidant activity, and phenols, anthocyanins or colour formation. Experimental data support the idea that Na-Chl-based photosensitization can be a useful tool for the future development of nonthermal food preservation technology. © 2011 The Authors. Journal of Applied Microbiology © 2011 The Society for Applied Microbiology.

  16. The nature, fabrication, and applications of photosensitive, bulk, germano-silicate glass

    NASA Astrophysics Data System (ADS)

    Heaney, Alan Douglas

    2000-08-01

    The photosensitive nature of germano-silicate glass is widely used to create fiber-optic devices. This thesis examines the cause of photosensitivity in germano- silicate glass. The results of this research elucidate the role that germanium oxygen deficient defects play in the photosensitivity of hydrogen-loaded, germano-silicate glass. We find that defects are not vital to the photosensitivity of hydrogen-loaded, germano-silicate glass but they do enhance the effect. Quantitative measurements show that germanium oxygen deficient defects promote the formation of OH, GeH, and GeH2 when hydrogen-loaded, germano-silicate glass is exposed to ultraviolet light. A sol-gel process for fabricating germano-silicate glass in bulk samples has been developed. The sol-gel process produces high-quality, germano-silicate glass which can be tailored to contain defects or be relatively free of defects. Control over the glass defect concentration allows us to use sol-gel derived glass for comparative studies of the photosensitive process and for device applications. The unique properties of germano-silicate glass make it a likely choice for use in optical applications. To prove the feasibility of bulk devices, chirped-pulse amplification is demonstrated using gratings written in bulk germano-silicate glass.

  17. Fundamental study on photodynamic therapy for atrial fibrillation: effect of photosensitization reaction parameters on myocardial necrosis in vitro

    NASA Astrophysics Data System (ADS)

    Ogawa, Emiyu; Ito, Arisa; Arai, Tsunenori

    2012-03-01

    We studied necrotic cell death effect on myocardial cells with photosensitizer existed outside the cells varying photosensitization reaction parameters widely in vitro. We have developed non-thermal ablator with the application of photosensitization reaction for atrial fibrillation. Since laser irradiation is applied shortly after photosensitizer injection, the photosensitization reaction is induced outside the cells. The interaction for the myocardial cells by the photosensitization reaction is not well understood yet on various photosensitization reaction parameters. Rat myocardial cells were cultured in 96 well plates for 7 days. The photosensitization reaction was applied with talaporfin sodium (NPe6) and the semiconductor laser of 663nm wavelength. The average drug light interval was set 8 mins. The photosensitizer concentration and radiant exposure were varied from 5 to 40 μg/ml and 1.2 to 60 J/cm2, respectively. The well bottom was irradiated by the red laser with irradiance of 293 mW/cm2. The photosensitizer fluorescence was monitored during the photosensitization reaction. Alive cell rate was measured by WST assay after 2 hours from the irradiation. In the case of the photosensitizer concentration of 10 μg/ml, the myocardial cells were almost alive even thought 60 J/cm2 in the radiant exposure was applied. In the 15 μg/ml case, the alive cell rate was almost linear relation to the photosensitizer concentration and radiant exposure. We obtained that the threshold for myocardial cell necrosis on the photosensitizer concentration was around 15 μg/ml with 20 J/cm2 in the radiant exposure. This threshold on the photosensitizer concentration was similar to the reported threshold for cancer therapy.

  18. In vivo photoacoustic monitoring of photosensitizer in skin: application to dosimetry for antibacterial photodynamic treatment

    NASA Astrophysics Data System (ADS)

    Hirao, Akihiro; Sato, Shunichi; Saitoh, Daizoh; Shinomiya, Nariyoshi; Ashida, Hiroshi; Obara, Minoru

    2009-02-01

    To obtain efficient antibacterial photodynamic effect in traumatic injuries such as burns, depth-resolved dosimetry of photosensitizer is required. In this study, we performed dual-wavelength photoacoustic (PA) measurement for rat burned skins injected with a photosensitizer. As a photosensitizer, methylene blue (MB) or porfimer sodium was injected into the subcutaneous tissue in rats with deep dermal burn. The wound was irradiated with red (665 nm or 630 nm) pulsed light to excite photosensitizers and green (532 nm) pulsed light to excite blood in the tissue; the latter signal was used to eliminate blood-associated component involved in the former signal. Acoustic attenuation was also compensated from the photosensitizer-associated PA signals. These signal processing was effective to obtain high-contrast image of a photosensitizer in the tissue. Behaviors of MB and porfimer sodium in the tissue were compared.

  19. In-vitro singlet oxygen threshold dose at PDT with Radachlorin photosensitizer

    NASA Astrophysics Data System (ADS)

    Klimenko, V. V.; Shmakov, S. V.; Kaydanov, N. E.; Knyazev, N. A.; Kazakov, N. V.; Rusanov, A. A.; Bogdanov, A. A.; Dubina, M. V.

    2017-07-01

    In this present study we investigate the Radachlorin photosensitizer accumulation in K562 cells and Hela cells and determined the cell viability after PDT. Using the macroscopic singlet oxygen modeling and cellular photosensitizer concentration the singlet oxygen threshold doses for K562 cells and Hela cells were calculated.

  20. Glucose-functionalized amino-OPEs as biocompatible photosensitizers in PDT.

    PubMed

    Deni, Elisa; Zamarrón, Alicia; Bonaccorsi, Paola; Carmen Carreño, M; Juarranz, Ángeles; Puntoriero, Fausto; Sciortino, Maria Teresa; Ribagorda, María; Barattucci, Anna

    2016-03-23

    Photodynamic therapy (PDT) is a minimally invasive procedure that can provide a selective eradication of neoplastic diseases by the combined effect of a photosensitizer, light and oxygen. New amino oligo(phenylene-ethynylene)s (OPEs), bearing hydrophilic glucoside terminations, have been prepared, characterized and tested as photosensitizers in PDT. The effectiveness of these compounds in combination with UVA light has been checked on two tumor cell lines (HEp-2 and HeLa cells, derived from a larynx carcinoma and a cervical carcinoma, respectively). The compounds triggered a mitotic blockage that led to the cell death, being the effect active up to 3 μm concentration. The photophysical properties of OPEs, such as high quantum yield, stability, singlet oxygen production, biocompatibility, easy cell-internalization and very good response even at low concentration, make them promising photosensitizers in the application of PDT. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  1. 3-D photo-patterning of refractive index structures in photosensitive thin film materials

    DOEpatents

    Potter, Jr., Barrett George; Potter, Kelly Simmons

    2002-01-01

    A method of making a three-dimensional refractive index structure in a photosensitive material using photo-patterning. The wavelengths at which a photosensitive material exhibits a change in refractive index upon exposure to optical radiation is first determined and then a portion of the surface of the photosensitive material is optically irradiated at a wavelength at which the photosensitive material exhibits a change in refractive index using a designed illumination system to produce a three-dimensional refractive index structure. The illumination system can be a micro-lenslet array, a macroscopic refractive lens array, or a binary optic phase mask. The method is a single-step, direct-write procedure to produce a designed refractive index structure.

  2. [Spectral properties of new photosensitizers for photodynamic diagnosis and therapy].

    PubMed

    Li, Bu-hong; Xie, Shu-sen; Lu, Zu-kang

    2002-12-01

    The spectral properties of new photosensitizer ZnPcS2P2, PsD-007 and HMME, as well as traditional photosensitizer HpD have been studied by comparing their spectra in physiological saline and in physiological saline with 10 percent serum. Experimental results show that the maximum absorption peaks for PsD-007, HMME and HpD in the physiological saline with 10 percent serum appear at 400 nm in the soret region, while at 670 nm for ZnPcS2P2. The fluorescence excitation spectra closely resemble the absorption spectra. When excited by the light at the wavelengths of 413 and 514.5 nm, the fluorescence emission peaks for PsD-007, HMME and HpD appear at 625 and 690 nm, respectively. The fluorescent excitation efficiency of the same photosensitizer with the same concentration excited by the light at the wavelength of 413 nm is about three fold higher than that at 514.5 nm. Furthermore, the fluorescent excitation efficiency is the highest for HMME, but is lower for HpD and lowest for PsD-007. These results are significant in the selection of photosensitizers for photodynamic diagnosis and therapy.

  3. Mapping a new black spot resistance locus in rose [abstract

    USDA-ARS?s Scientific Manuscript database

    Rose black spot, caused by Diplocarpon rosae, is one of the most devastating foliar diseases of cultivated roses (Rosa hybrida). The pathogen is globally distributed and has the potential to cause large economic losses in the outdoor rose industry. Genetic resistance is the most economical disease m...

  4. Mechanism of colon cancer cell apoptosis mediated by pyropheophorbide-a methylester photosensitization.

    PubMed

    Matroule, J Y; Carthy, C M; Granville, D J; Jolois, O; Hunt, D W; Piette, J

    2001-07-05

    Pyropheophorbide-a methylester (PPME) is a second generation of photosensitizers used in photodynamic therapy (PDT). We demonstrated that PPME photosensitization triggered apoptosis of colon cancer cells as measured by using several classical parameters such as DNA laddering, PARP cleavage, caspase activation and mitochondrial release of cytochrome c. Preincubation of cells with N-acetyl cysteine (NAC) or pyrolidine dithiocarbamate (PDTC) protected against apoptosis mediated by PPME photosensitization showing that reactive oxygen species (ROS) are involved as second messengers. On the other hand, photosensitization carried out in the presence of deuterium oxide (D2O) which enhances singlet oxygen (1O2) lifetime only increases necrosis without affecting apoptosis. Since PPME was localized in the endoplasmic reticulum (ER)/Golgi system and lysosomes, other messengers than ROS were tested such as calcium, Bid, Bap31, phosphorylated Bcl-2 and caspase-12 but none was clearly identified as being involved in triggering cytochrome c release from mitochondria. On the other hand, we demonstrated that the transduction pathways leading to NF-kappaB activation and apoptosis were clearly independent although NF-kappaB was shown to counteract apoptosis mediated by PPME photosensitization.

  5. Positive deviance--the West Bengal experience.

    PubMed

    Mustaphi, P; Dobe, M

    2005-01-01

    There are 11.1 million children in the age group 0-6 years in West Bengal. Of these, every second child under 3 years of age is underweight, more than four out of ten are stunted, and one out of eight are wasted. The Integrated Child Development Services (ICDS) programme in West Bengal has 355 operational projects covering 53,064 operational anganwadi centers reaching out to more than four million beneficiaries--approximately half of whom are children in the age group 0-3 years. The Department of Women and Child Development (DWCD) is trying to identify and replicate innovative, community-based, sustainable approaches. One such innovative initiative has been the "Keno Parbo Na" project based on the Positive Deviance (PD) approach which aims to reduce and prevent malnutrition among children under 3 years of age by focusing on local solutions and resources, local behaviors and practices. Behavior change is emphasized through participatory learning and community mobilization. The pilot phase of the project has been completed in two districts [Four blocks (2 in each District) and 32 villages/AWCs (8 in each block)] of West Bengal (Murshidabad and South 24 Parganas). The analysis of the project activities so far reveals that the issue of malnutrition and its prevention is now visible in the villages covered. Acceptance of desirable behavioral practices is observed within the community. A steady reduction in the moderate and severe level of malnutrition was noted across four districts. A general preponderance of girl children was noted at the entry stage indicating higher levels of severe and moderate malnutrition among girl children to begin with but also suggesting PD as an important strategy in reducing the gender gap in malnutrition. The boys gain in terms of nutritional status faster than the girls so in the intermediate phase malnourished girls are more in number. However, by the sixth / ninth round, as the malnutrition levels decline substantially, the gender gap

  6. Tiger, Bengal and Domestic Cat Embryos Produced by Homospecific and Interspecific Zona-Free Nuclear Transfer.

    PubMed

    Moro, L N; Jarazo, J; Buemo, C; Hiriart, M I; Sestelo, A; Salamone, D F

    2015-10-01

    The aim of this study was to evaluate three different cloning strategies in the domestic cat (Felis silvestris) and to use the most efficient to generate wild felid embryos by interspecific cloning (iSCNT) using Bengal (a hybrid formed by the cross of Felis silvestris and Prionailurus bengalensis) and tiger (Panthera tigris) donor cells. In experiment 1, zona-free (ZP-free) cloning resulted in higher fusion and expanded blastocyst rates with respect to zona included cloning techniques that involved fusion or injection of the donor cell. In experiment 2, ZP-free iSCNT and embryo aggregation (2X) were assessed. Division velocity and blastocyst rates were increased by embryo aggregation in the three species. Despite fewer tiger embryos than Bengal and cat embryos reached the blastocyst stage, Tiger 2X group increased the percentage of blastocysts with respect to Tiger 1X group (3.2% vs 12.1%, respectively). Moreover, blastocyst cell number was almost duplicated in aggregated embryos with respect to non-aggregated ones within Bengal and tiger groups (278.3 ± 61.9 vs 516.8 ± 103.6 for Bengal 1X and Bengal 2X groups, respectively; 41 vs 220 ± 60 for Tiger 1X and Tiger 2X groups, respectively). OCT4 analysis also revealed that tiger blastocysts had higher proportion of OCT4-positive cells with respect to Bengal blastocysts and cat intracytoplasmic sperm injection blastocysts. In conclusion, ZP-free cloning has improved the quality of cat embryos with respect to the other cloning techniques evaluated and was successfully applied in iSCNT complemented with embryo aggregation. © 2015 Blackwell Verlag GmbH.

  7. Permeability of DOPC bilayers under photoinduced oxidation: Sensitivity to photosensitizer.

    PubMed

    Bacellar, Isabel O L; Baptista, Mauricio S; Junqueira, Helena C; Wainwright, Mark; Thalmann, Fabrice; Marques, Carlos M; Schroder, André P

    2018-06-07

    The modification of lipid bilayer permeability is one of the most striking yet poorly understood physical transformations that follow photoinduced lipid oxidation. We have recently proposed that the increase of permeability of photooxidized 1,2-dioleoyl-sn-glycero-3-phosphocholine (DOPC) bilayers is controlled by the time required by the oxidized lipid species to diffuse and aggregate into pores. Here we further probe this mechanism by studying photosensitization of DOPC membranes by methylene blue (MB) and DO15, a more hydrophobic phenothiazinium photosensitizer, under different irradiation powers. Our results not only reveal the interplay between the production rate and the diffusion of the oxidized lipids, but highlight also the importance of photosensitizer localization in the kinetics of oxidized membrane permeability. Copyright © 2018. Published by Elsevier B.V.

  8. Photosensitizers derived from 132-oxo-methyl pyropheophorbide-a: enhanced effect of indium(III) as a central metal in in vitro and in vivo photosensitizing efficacy.

    PubMed

    Rosenfeld, Andrew; Morgan, Janet; Goswami, Lalit N; Ohulchanskyy, Tymish; Zheng, Xiang; Prasad, Paras N; Oseroff, Allan; Pandey, Ravindra K

    2006-01-01

    The effects of an additional keto group on absorption wavelength and the corresponding metal complexes Zn(II), Cu(II) In(III) on singlet oxygen production and photodynamic efficacy were examined among the alkyl ether analogs of pyropheophorbide-a. For the preparation of the desired photosensitizers, the methyl 13(2)-oxo-pyropheophorbide-a obtained by reacting methyl pyropheophorbide-a with aqueous LiOH-THF was converted into a series of alkyl ether analogs. These compounds were evaluated for photophysical properties and in vitro (by means of the MTT assay and intracellular localization in RIF cells) and in vivo (in C3H mice implanted with RIF tumors) photosensitizing efficacy. Among the alkyl ether derivatives, the methyl 3-decyloxyethyl-3-devinyl-13(2)-oxo-pyropheophorbide-a was found to be most effective and the insertion of In(III) into this analog further enhanced its in vitro and in vivo photosensitizing efficacy. Fluorescence microscopy showed that, in contrast to the hexyl and dodecyl ether derivatives of HPPH (which localize in mitochondria and lysosomes, respectively), the diketo-analogs and their In(III) complexes localized in Golgi bodies. The preliminary in vitro and in vivo results suggest that, in both free-base and metalated analogs, the introduction of an additional keto group at the five-member exocyclic ring in pyropheophorbide-a diminishes its photosensitizing efficacy. This may be due to a shift in subcellular localization from mitochondria to the Golgi bodies. The further introduction of In(III) enhances photoactivity, but not by shifting the localization of the photosensitizer.

  9. An Intrathermocline Eddy and a tropical cyclone in the Bay of Bengal

    NASA Astrophysics Data System (ADS)

    Gordon, Arnold L.; Shroyer, Emily; Murty, V. S. N.

    2017-04-01

    The Bay of Bengal, subjected to monsoonal forcing and tropical cyclones, displays a complex field of ocean eddies. On 5 December 2013 a sub-surface vortex or Intrathermocline Eddy (ITE) composed of water characteristic of the Andaman Sea was observed within the thermocline of the western Bay of Bengal. We propose that the ITE was the product of Tropical Cyclone Lehar interaction on 27 November 2013 with a westward propagating surface eddy from the eastern Bay of Bengal. While Lehar’s interaction with the ocean initially removes heat from the upper layers of the eddy, air-sea flux is limited as the deeper portions of the eddy was subducted into the stratified thermocline, inhibiting further interaction with the atmosphere. The ITE core from 30 to 150 m is thus isolated from local air-sea fluxes by strong stratification at the mixed layer base, and its periphery is stable to shear instability, suggestive of longevity and the ability to carry water far distances with minimal modification.

  10. An Intrathermocline Eddy and a tropical cyclone in the Bay of Bengal.

    PubMed

    Gordon, Arnold L; Shroyer, Emily; Murty, V S N

    2017-04-12

    The Bay of Bengal, subjected to monsoonal forcing and tropical cyclones, displays a complex field of ocean eddies. On 5 December 2013 a sub-surface vortex or Intrathermocline Eddy (ITE) composed of water characteristic of the Andaman Sea was observed within the thermocline of the western Bay of Bengal. We propose that the ITE was the product of Tropical Cyclone Lehar interaction on 27 November 2013 with a westward propagating surface eddy from the eastern Bay of Bengal. While Lehar's interaction with the ocean initially removes heat from the upper layers of the eddy, air-sea flux is limited as the deeper portions of the eddy was subducted into the stratified thermocline, inhibiting further interaction with the atmosphere. The ITE core from 30 to 150 m is thus isolated from local air-sea fluxes by strong stratification at the mixed layer base, and its periphery is stable to shear instability, suggestive of longevity and the ability to carry water far distances with minimal modification.

  11. Downy mildew: a serious disease threat to rose health worldwide

    USDA-ARS?s Scientific Manuscript database

    Peronospora sparsa is a downy mildew-causing oomycete that can infect roses, blackberries and other members of the rose family. During the last 20 years, this disease has become a serious problem for rose growers in the U.S. and worldwide. While much is known about the disease and its treatment, inc...

  12. The Bay of Bengal : an ideal laboratory for studying salinity

    NASA Astrophysics Data System (ADS)

    Vialard, jerome; Lengaigne, Matthieu; Akhil, Valiya; Chaitanya, Akurathi; Krishna-Mohan, Krishna; D'Ovidio, Francesco; Keerthi, Madhavan; Benshila, Rachid; Durand, Fabien; Papa, Fabrice; Suresh, Iyappan; Neetu, Singh

    2017-04-01

    The Bay of Bengal combines several unique features that make it an excellent laboratory to study the variability of salinity and its potential effects on the oceanic circulation and climate. This basin receives very large quantities of freshwater in association to the southwest monsoon, either directly from rain or indirectly through the runoffs of the Ganges-Brahmaputra and Irrawaddy. This large quantity of freshwater in a small, semi enclosed basin results in some of the lowest sea surface salinities (SSS) and strongest near-surface haline stratification in the tropical band. The strong monsoon winds also drive an energetic circulation, which exports the excess water received during the monsoon and results in strong horizontal salinity gradients. In this talk, I will summarize several studies of the Bay of Bengal salinity variability and its impacts undertaken in the context of an Indo-French collaboration. In situ data collected along the coast by fishermen and model results show that the intense, coastally-trapped East India Coastal Current (EICC) transports the very fresh water near the Ganges-Brahmaputra river mouth along the eastern Bay of Bengal rim to create a narrow, very fresh "river in the sea" after the southwest monsoon. The salinity-induced pressure gradient contributes to almost 50% of the EICC intensity and sustains mesoscale eddy generation through its effect on horizontal current shears and baroclinic gradients. Oceanic eddies play a strong role in exporting this fresh water from the coast to the basin interior. This "river in the sea" has a strong interannual variability related to the EICC remote modulation by the Indian Ocean Dipole (a regional climate mode). I will also discuss the potential effect of haline stratification on the regional climate through its influence on the upper ocean budget. Finally, I will briefly discuss the performance of remote-sensing for observing SSS in the Bay of Bengal.

  13. Dissecting black spot resistance in polyploid hybrid roses

    USDA-ARS?s Scientific Manuscript database

    Devastating foliar diseases, such as black spot caused by Diplocarpon rosae, pose constant threats to the ornamental quality of outdoor grown roses. Black spot is primarily managed though the use of fungicides, however, there is a high demand for resistant roses which require low chemical inputs. To...

  14. Smart Photosensitizer: Tumor-Triggered Oncotherapy by Self-Assembly Photodynamic Nanodots.

    PubMed

    Jia, Yuhua; Li, Jinyu; Chen, Jincan; Hu, Ping; Jiang, Longguang; Chen, Xueyuan; Huang, Mingdong; Chen, Zhuo; Xu, Peng

    2018-05-09

    Clinical photosensitizers suffer from the disadvantages of fast photobleaching and high systemic toxicities because of the off-target photodynamic effects. To address these problems, we report a self-assembled pentalysine-phthalocyanine assembly nanodots (PPAN) fabricated by an amphipathic photosensitizer-peptide conjugate. We triggered the photodynamic therapy effects of photosensitizers by precisely controlling the assembly and disintegration of the nanodots. In physiological aqueous conditions, PPAN exhibited a size-tunable spherical conformation with a highly positive shell of the polypeptides and a hydrophobic core of the π-stacking Pc moieties. The assembly conformation suppressed the fluorescence and the reactive oxygen species generation of the monomeric photosensitizer molecules (mono-Pc) and thus declined the photobleaching and off-target photodynamic effects. However, tumor cells disintegrated PPAN and released the mono-Pc molecules, which exhibited fluorescence for detection and the photodynamic effects for the elimination of the tumor tissues. The molecular dynamics simulations revealed the various assembly configurations of PPAN and illustrated the assembly mechanism. At the cellular level, PPAN exhibited a remarkable phototoxicity to breast cancer cells with the IC 50 values in a low nanomolar range. By using the subcutaneous and orthotopic breast cancer animal models, we also demonstrated the excellent antitumor efficacies of PPAN in vivo.

  15. Off-Resonance Photosensitization of a Photorefractive Polymer Composite Using PbS Nanocrystals

    DOE PAGES

    Moon, Jong-Sik; Liang, Yichen; Stevens, Tyler E.; ...

    2015-05-26

    The photosensitization of photorefractive polymeric composites for operation at 633 nm is accomplished through the inclusion of narrow band gap semiconductor nanocrystals composed of PbS. Unlike previous studies involving photosensitization of photorefractive polymer composites with inorganic nanocrystals, we employ an off-resonance approach where the first excitonic transition associated with the PbS nanocrystals lies at ~1220 nm and not the wavelength of operation. Using this methodology, internal diffraction efficiencies exceeding 82%, two-beam-coupling gain coefficients of 211 cm –1, and response times of 34 ms have been observed, representing some of the best figures of merit reported for this class of materials.more » Furthermore, these data demonstrate the ability of semiconductor nanocrystals to compete effectively with traditional organic photosensitizers. In addition to superior performance, this approach also offers an inexpensive and easy means by which to photosensitize composite materials. Additionally, the photoconductive characteristics of the composites used for this study will also be considered.« less

  16. Memory restoring and neuroprotective effects of the proline-containing dipeptide, GVS-111, in a photochemical stroke model.

    PubMed

    Ostrovskaya, R U; Romanova, G A; Barskov, I V; Shanina, E V; Gudasheva, T A; Victorov, I V; Voronina, T A; Seredenin, S B

    1999-09-01

    Local thrombosis of the frontal cortex (Fr1 and Fr3 fields), caused by combination of the intravenous photosensitive dye Rose Bengal administration with focused high-intensity illumination of the frontal bone, was shown to provoke a pronounced deficit in step-through passive avoidance performance in rats without concomitant motor disturbances. N-Phenylacetyl-L-prolylglycine ethyl ester (GVS-111) administered intravenously at a dose of 0.5 mg/kg/day, for the first time 1 h after ischaemic lesion and then for 9 post-operative days, with the last administration 15 min before testing, attenuated the deficit. This treatment significantly diminished the volume of the infarcted area. Thus, post-ischaemic injection of GVS-111 demonstrated both cognition-restoring and neuroprotective properties. The cognition-restoring effect is probably based on an increase in neocortical and hippocampal neuronal plasticity. Neuroprotective effects of GVS-111 combine antioxidant activity with the ability to attenuate glutamate-provoked neurotoxicity and block voltage-gated ionic channels, i.e. the compound mitigates the main metabolic shifts involved in pathogenesis of brain ischaemia.

  17. Spatial photosensitizer fluorescence emission predictive analysis for photodynamic therapy monitoring applied to a skin disease

    NASA Astrophysics Data System (ADS)

    Salas-García, Irene; Fanjul-Vélez, Félix; Arce-Diego, José Luis

    2012-03-01

    The development of Photodynamic Therapy (PDT) predictive models has become a valuable tool for an optimal treatment planning, monitoring and dosimetry adjustment. A few attempts have achieved a quite complete characterization of the complex photochemical and photophysical processes involved, even taking into account superficial fluorescence in the target tissue. The present work is devoted to the application of a predictive PDT model to obtain fluorescence tomography information during PDT when applied to a skin disease. The model takes into account the optical radiation distribution, a non-homogeneous topical photosensitizer distribution, the time dependent photochemical interaction and the photosensitizer fluorescence emission. The results show the spatial evolution of the photosensitizer fluorescence emission and the amount of singlet oxygen produced during PDT. The depth dependent photosensitizer fluorescence emission obtained is essential to estimate the spatial photosensitizer concentration and its degradation due to photobleaching. As a consequence the proposed approach could be used to predict the photosensitizer fluorescence tomographic measurements during PDT. The singlet oxygen prediction could also be employed as a valuable tool to predict the short term treatment outcome.

  18. [Comparative toxicity of photosensitizers in varying destruction].

    PubMed

    Sinitsina, O O; Zholdakova, Z I; Poliakova, E E; Golovach, E N; Sycheva, L P; Beliaeva, N N; Kuznetsova, N A

    2007-01-01

    The toxicity of the photosensitizers proflavine acetate (PA) versus methylene blue (MB) was evaluated during their varying destruction. Under the influence of visible light, a partial (25%) transformation of the photosensitizers was shown to be attended by their enhanced toxicity and 100% destruction of the parent substances caused a reduction in their hazard. PA and its phototransformation products mainly affect the antiperoxide protection system and the structural and functional states of the liver, kidney, and duodenum. The maximum noneffective dose is 0.002 mg/kg. The possibility of using PA for water disinfection depends on the ratio of safe and effective concentrations. A partial (25%) MB destruction products cause mutagenic effects; the permissible dose of the mutagen is 0.00025 mg/kg. MB is not recommended for disinfection of all types of waters.

  19. Phosphorescence dynamics of singlet oxygen and Radachlorin photosensitizer in aqueous solution

    NASA Astrophysics Data System (ADS)

    Belik, V. P.; Beltukova, D. M.; Gadzhiev, I. M.; Semenova, I. V.; Vasyutinskii, O. S.

    2017-07-01

    The luminescence spectrum of aqueous solution of Radachlorin photosensitizer in the near IR spectral range (950-1350 nm) has been determined at the excitation in both the Soret and Q absorption bands. Major sources of the recorded luminescence were analyzed. Kinetics of photosensitizer and singlet oxygen phosphorescence signals were studied by means of time-resolved spectroscopy. The corresponding characteristic lifetimes were determined.

  20. Photosensitive epilepsy is associated with reduced inhibition of alpha rhythm generating networks

    PubMed Central

    Vaudano, Anna Elisabetta; Ruggieri, Andrea; Avanzini, Pietro; Gessaroli, Giuliana; Cantalupo, Gaetano; Coppola, Antonietta; Sisodiya, Sanjay M.

    2017-01-01

    Abstract See Hamandi (doi:10.1093/awx049) for a scientific commentary on this article. Photosensitivity is a condition in which lights induce epileptiform activities. This abnormal electroencephalographic response has been associated with hyperexcitability of the visuo-motor system. Here, we evaluate if intrinsic dysfunction of this network is present in brain activity at rest, independently of any stimulus and of any paroxysmal electroencephalographic activity. To address this issue, we investigated the haemodynamic correlates of the spontaneous alpha rhythm, which is considered the hallmark of the brain resting state, in photosensitive patients and in people without photosensitivity. Second, we evaluated the whole-brain functional connectivity of the visual thalamic nuclei in the various populations of subjects under investigation. Forty-four patients with epilepsy and 16 healthy control subjects underwent an electroencephalography-correlated functional magnetic resonance imaging study, during an eyes-closed condition. The following patient groups were included: (i) genetic generalized epilepsy with photosensitivity, 16 subjects (mean age 25 ± 10 years); (ii) genetic generalized epilepsy without photosensitivity, 13 patients (mean age 25 ± 11 years); (iii) focal epilepsy, 15 patients (mean age 25 ± 9 years). For each subject, the posterior alpha power variations were convolved with the standard haemodynamic response function and used as a regressor. Within- and between-groups second level analyses were performed. Whole brain functional connectivity was evaluated for two thalamic regions of interest, based on the haemodynamic findings, which included the posterior thalamus (pulvinar) and the medio-dorsal thalamic nuclei. Genetic generalized epilepsy with photosensitivity demonstrated significantly greater mean alpha-power with respect to controls and other epilepsy groups. In photosensitive epilepsy, alpha-related blood oxygen level-dependent signal changes

  1. Photosensitized Formation of Secondary Organic Aerosols above the Air/Water Interface

    PubMed Central

    2016-01-01

    In this study, we evaluated photosensitized chemistry at the air–sea interface as a source of secondary organic aerosols (SOA). Our results show that, in addition to biogenic emissions, abiotic processes could also be important in the marine boundary layer. Photosensitized production of marine secondary organic aerosol was studied in a custom-built multiphase atmospheric simulation chamber. The experimental chamber contained water, humic acid (1–10 mg L–1) as a proxy for dissolved organic matter, and nonanoic acid (0.1–10 mM), a fatty acid proxy which formed an organic film at the air–water interface. Dark secondary reaction with ozone after illumination resulted in SOA particle concentrations in excess of 1000 cm–3, illustrating the production of unsaturated compounds by chemical reactions at the air–water interface. SOA numbers via photosensitization alone and in the absence of ozone did not exceed background levels. From these results, we derived a dependence of SOA numbers on nonanoic acid surface coverage and dissolved organic matter concentration. We present a discussion on the potential role of the air–sea interface in the production of atmospheric organic aerosol from photosensitized origins. PMID:27434860

  2. Tetrapyrrole-photosensitizers vectorization and plasma LDL: a physico-chemical approach.

    PubMed

    Bonneau, Stéphanie; Vever-Bizet, Christine; Mojzisova, Halina; Brault, Daniel

    2007-11-01

    A photosensitizer is defined as a chemical entity able to induce, under light-irradiation effect, a chemical or physical alteration of another chemical entity. Thanks to their preferential retention in proliferating tissues, some photosensitizers are therapeutically used such as in photodynamic therapy (PDT). Besides, this method has already been approved for several indications. The selectivity of photosenzitizers for cells in proliferation involves both their association with low density lipoproteins (LDLs) and their ability to cross membranes under various pH conditions. The photosensitizers used are in most cases based on the porphyrin structure, but other compounds, of which far-red-light absorption properties are most compatible with biological tissues irradiation, have been developed, such as phthalocyanines. This paper presents physico-chemical studies of the interaction of a disulfonated aluminium phthalocyanine (AlPcS2) with human LDLs. The data obtained are compared with the parameters of the interaction of these lipoproteins with deuteroporphyrin (DP) and chlorin e6 (Ce6). A close attention is paid to the dynamic aspects of these phenomena. The data obtained on these simple systems then allowed us to interpret the sub-cellular localization of the photosensitizers on a human line of fibroblasts, and to evaluate the influence of LDLs on the intracellular distribution of the compounds. This last point is of major importance because the localization of such photosensitizers (in particular AlPcS2) in endocytic vesicles and their subsequent ability to induce a release of the contents of these vesicles - including externally added macromolecules - into the cytosol is the basis for a recent method for macromolecule activation, named photochemical internalization (PCI). PCI has been shown to potentiate the biological activity of a large variety of macromolecules. The comprehension of the mechanisms governing this particular sub-cellular localization could allow

  3. Development of polyclonal and monoclonal antibodies to Rose rosette virus nucleoprotein

    USDA-ARS?s Scientific Manuscript database

    Garden roses, which form the cornerstone of the multi-billion dollar landscape industry, annually generate wholesale US domestic production valued at ca. $400 million. Over the past few decades Rose rosette disease, caused by Rose rosette virus (RRV; genus Emaravirus), has become a major threat to t...

  4. 76 FR 28315 - Security Zone; Portland Rose Festival on Willamette River

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-17

    ... Zone; Portland Rose Festival on Willamette River AGENCY: Coast Guard, DHS. ACTION: Notice of enforcement of regulation. SUMMARY: The Coast Guard will enforce the Portland Rose Festival Security Zone in... River during the Portland Rose festival. During the enforcement period, no person or vessel may enter or...

  5. An Intrathermocline Eddy and a tropical cyclone in the Bay of Bengal

    PubMed Central

    Gordon, Arnold L.; Shroyer, Emily; Murty, V. S. N.

    2017-01-01

    The Bay of Bengal, subjected to monsoonal forcing and tropical cyclones, displays a complex field of ocean eddies. On 5 December 2013 a sub-surface vortex or Intrathermocline Eddy (ITE) composed of water characteristic of the Andaman Sea was observed within the thermocline of the western Bay of Bengal. We propose that the ITE was the product of Tropical Cyclone Lehar interaction on 27 November 2013 with a westward propagating surface eddy from the eastern Bay of Bengal. While Lehar’s interaction with the ocean initially removes heat from the upper layers of the eddy, air-sea flux is limited as the deeper portions of the eddy was subducted into the stratified thermocline, inhibiting further interaction with the atmosphere. The ITE core from 30 to 150 m is thus isolated from local air-sea fluxes by strong stratification at the mixed layer base, and its periphery is stable to shear instability, suggestive of longevity and the ability to carry water far distances with minimal modification. PMID:28401909

  6. Mini review on photosensitization by plants in grazing herbivores.

    PubMed

    Hussain, Syeda M; Herling, Valdo Rodrigues; Rodrigues, Paulo Henrique Mazza; Naz, Ishrat; Khan, Hamayun; Khan, Muhammad Tahir

    2018-06-01

    Photosensitization is severe dermatitis or oxidative/chemical changes in the epidermal tissues activated by the light-induced excitation of molecules within the tissue. It is a series of reactions mediated through light receptors and is more common when the plant-produced metabolites are heterocyclic/polyphenols in nature. The areas affected are exposed body parts and mostly non-pigmented areas with least ultraviolet protection. Similarly, cellular alteration also occurs in the affected animal's dermal tissues and body parts and grazing animals by the accumulation and activation of photodynamic molecules. Photo-oxidation can also occur within the plant due to the generation of reactive oxygen species causing damage and degradation in the form of free radicals and DNA. During the last few decades, many new tropical grass species have been introduced in the grazing lands which are genetically modified, and the animals grazing on them are facing various forms of toxicity including photosensitization. The plant's secondary metabolites/drugs may cause toxicity when bacteria, viral agents, fungi (Pithomyces chartarum), or neoplasia injures the liver and prevents the phylloerythrin excretion. All these may disturb the liver enzymes and blood profile causing a decrease in weight and production (wool and milk etc.) with severe dermal, digestive, and nervous problems. Recent advancements in OMICS (cellomics, ethomics, metabolomics, metabonomics, and glycomics) have enabled us to detect and identify the plants' secondary metabolites and changes in the animal's physiology and histopathology as a causative of photosensitivity. The review focuses on types of photosensitization, reasons, secondary metabolic compounds, chemistry, and environmental effect on plants.

  7. Photosensitized inactivation of infectious blood-borne human parasites

    NASA Astrophysics Data System (ADS)

    Judy, Millard M.; Sogandares-Bernal, Franklin M.; Matthews, James Lester

    1995-05-01

    Blood-borne viruses and protozoan parasites that are infectious to humans pose risk world-wide of infection transmission through blood and blood product transfusion. Blood-borne infectious viruses include human immunodeficiency virus (HIV-I), which causes AIDS; hepatitis C virus, which can cause chronic hepatitis; and cytomegalovirus, which can be dangerous to immunocompromised patients, e.g., the newborn, transplant recipients, and AIDS patients. Infectious blood-borne protozoan parasites include Trypanosoma cruzi, which causes Chagas' disease, endemic throughout Central and South America; the Trypanosoma species causing African sleeping sickness endemic in Central Africa; and Plasmodium falciparum, which causes malignant and increasingly drug- resistant human malaria prevalent throughout the tropics. Some researchers have focused on using photosensitizers to inactivate HIV-I and other viruses in whole blood, packed red cells, and platelet concentrates without compromising blood product function. Our group previously has reported photosensitized in vitro inactivation of P. falciparum and the mouse malaria organism Plasmodium berghei in whole blood using hematoporphyrin derivative (HPD) and of T. cruzi using benzoporphyrin derivatives BPDMA and BPDDA, dihematoporphyrin ether (DHE), and hydroxyethylvinyldeuteroporphyrin (HEVD). These results suggest that continued investigation is warranted to evaluate the potential for photosensitized inactivation of blood-borne parasites in blood banking.

  8. Chronic arsenic toxicity in Bangladesh and West Bengal, India--a review and commentary.

    PubMed

    Rahman, M M; Chowdhury, U K; Mukherjee, S C; Mondal, B K; Paul, K; Lodh, D; Biswas, B K; Chanda, C R; Basu, G K; Saha, K C; Roy, S; Das, R; Palit, S K; Quamruzzaman, Q; Chakraborti, D

    2001-01-01

    Fifty districts of Bangladesh and 9 districts in West Bengal, India have arsenic levels in groundwater above the World Health Organization's maximum permissible limit of 50 microg/L. The area and population of 50 districts of Bangladesh and 9 districts in West Bengal are 118,849 km2 and 104.9 million and 38,865 km2 and 42.7 million, respectively. Our current data show arsenic levels above 50 microg/ L in 2000 villages, 178 police stations of 50 affected districts in Bangladesh and 2600 villages, 74 police stations/blocks of 9 affected districts in West Bengal. We have so far analyzed 34,000 and 101,934 hand tube-well water samples from Bangladesh and West Bengal respectively by FI-HG-AAS of which 56% and 52%, respectively, contained arsenic above 10 microg/L and 37% and 25% arsenic above 50 microg/L. In our preliminary study 18,000 persons in Bangladesh and 86,000 persons in West Bengal were clinically examined in arsenic-affected districts. Of them, 3695 (20.6% including 6.11% children) in Bangladesh and 8500 (9.8% including 1.7% children) in West Bengal had arsenical dermatological features. Symptoms of chronic arsenic toxicity developed insidiously after 6 months to 2 years or more of exposure. The time of onset depends on the concentration of arsenic in the drinking water, volume of intake, and the health and nutritional status of individuals. Major dermatological signs are diffuse or spotted melanosis, leucomelanosis, and keratosis. Chronic arsenicosis is a multisystem disorder. Apart from generalized weakness, appetite and weight loss, and anemia, our patients had symptoms relating to involvement of the lungs, gastrointestinal system, liver, spleen, genitourinary system, hemopoietic system, eyes, nervous system, and cardiovascular system. We found evidence of arsenic neuropathy in 37.3% (154 of 413 cases) in one group and 86.8% (33 of 38 cases) in another. Most of these cases had mild and predominantly sensory neuropathy. Central nervous system involvement

  9. Voices of the poor from the margins of Bengal: structural inequities and health.

    PubMed

    Dutta, Mohan J; Dutta, Uttaran

    2013-01-01

    In opposition to the traditional approaches to health communication that treat the subaltern sectors as passive recipients of messages of enlightenment configured in top-down interventions, the culture-centered approach foregrounds the importance of listening to subaltern communities at the margins through dialogue. We build on earlier culture-centered projects in rural communities of West Bengal, India, to develop participatory research strategies for understanding the local processes through which the structural marginalization of the poor plays out in rural Bengal. Study results point toward the marginalization of the poor both communicatively and economically, attending to the ways in which communicative marginalization lies at the heart of economic oppressions. Through locally articulated concepts of "health as shortage" and "communication as shortage," community members put forth alternative rationalities of health that highlight structural resources at the heart of health. These local articulations of shortage offer an alternative rationality for organizing health promotion efforts in the rural margins of Bengal through the foregrounding of discourses of shortage.

  10. Photodynamic impact induces ischemic tolerance in models in vivo and in vitro

    NASA Astrophysics Data System (ADS)

    Demyanenko, Svetlana; Sharifulina, Svetlana; Berezhnaya, Elena; Kovaleva, Vera; Neginskaya, Maria; Zhukovskaya, Ludmila

    2016-04-01

    Ischemic tolerance determines resistance to lethal ischemia gained by a prior sublethal stimulus (i.e., preconditioning). We reproduced this effect in two variants. In vitro the preliminary short (5 s) photodynamic treatment (PDT) (photosensitizer Photosens, 10 nM, 30 min preincubation; laser: 670 nm, 100 mW/cm2) significantly reduced the necrosis of neurons and glial cells in the isolated crayfish stretch receptor, which was caused by following 30-min PDT by 66% and 46%, respectively. In vivo PDT of the rat cerebral cortex with hydrophilic photosensitizer Rose Bengal (i.v. administration, laser irradiation: 532 nm, 60 mW/cm2, 3 mm beam diameter, 30 min) caused occlusion of small brain vessels and local photothrombotic infarct (PTI). It is a model of ischemic stroke. Cerebral tissue edema and global necrosis of neurons and glial cells occurred in the infarction core, which was surrounded by a 1.5 mm transition zone, penumbra. The maximal pericellular edema, hypo- and hyperchromia of neurons were observed in penumbra 24 h after PTI. The repeated laser irradiation of the contralateral cerebral cortex also caused PTI but lesser as compared with single PDT. Preliminary unilateral PTI provided ischemic tolerance: at 14 day after second exposure the PTI volume significantly decreased by 24% than in the case of a single exposure. Sensorimotor deficits in PDT-treated rats was registered using the behavioral tests. The preliminary PTI caused the preconditioning effect.

  11. An unusual photosensitizer: dyad of eosin-tris(2,2'-bipyridine)Ru(II).

    PubMed

    Jing, Bingwen; Zhang, Manhua; Shen, Tao

    2003-10-02

    [structure: see text] A dyad of eosin and tris(2,2'-bipyridine)Ru(II) was prepared, and its photophysical properties were investigated. The photosensitization of eosin is greatly enhanced by introduction of tris(2,2'-bipyridine)Ru(II), which is verified via photooxygenation of anthracene derivatives. The electron-transfer mechanism of photosensitization is also discussed.

  12. Analysis of photodynamic therapy applied to skin disorders by a topical photosensitizer

    NASA Astrophysics Data System (ADS)

    Fanjul-Vélez, F.; Romanov, O. G.; López-Escobar, M.; Rodriguez-Colmenares, M. A.; Ortega-Quijano, N.; Arce-Diego, J. L.

    2008-11-01

    Optical treatment of pathological tissues comprises techniques like Low Intensity Laser Treatment (LILT) or Photodynamic Therapy (PDT). PDT consists on the inoculation of a photosensitizer in the tissue, which tends to be accumulated in cancerous cells, and on the posterior optical radiation of the area. The photosensitizer, that can be topical or systemic, is excited and cell necrosis is provoked. The collateral harmful effects of other destructive techniques, like radiotherapy or chemotherapy, are avoided with PDT. PDT can also be used as a complementary technique of conventional excisional surgical operations. The application of PDT to skin disorders is straightforward due to the fact that it is an external and accessible tissue. In this work, we analyze the application of PDT to several skin pathologies and the results obtained, by means of mainly the usage of MetvixR as a topical photosensitizer and with an optical source in the range of 635 nm. The analysis includes a predictive model of the PDT process, based on an optical propagation equation and a photosensitizer degradation approach that provides an estimation of tissue destruction.

  13. KORO SOCIAL RESPONSE (URBAN) : A LONGITUDINAL STUDY OF NORTH BENGAL KORO EPIDEMIC

    PubMed Central

    Chowdhury, Arabinda N.

    1992-01-01

    Social responses to Koro illness was studied from an urban population (n = 118) of Darjeeling district of West Bengal State, during and after the North Bengal Koro epidemic. The prevalent social cognition of Koro as a positive illness paradigm, both among the Koro-affected and non-affected families, was the important social dynamics that helped the epidemic to spread as the illness in the region. The cognition-intensity related to the Koro vulnerability has diminished gradually with the passing of time, which was well corroborated with the gradually weaning incidence curve of Koro illness in the region. PMID:21776098

  14. RhMKK9, a rose MAP KINASE KINASE gene, is involved in rehydration-triggered ethylene production in rose gynoecia.

    PubMed

    Chen, Jiwei; Zhang, Qian; Wang, Qigang; Feng, Ming; Li, Yang; Meng, Yonglu; Zhang, Yi; Liu, Guoqin; Ma, Zhimin; Wu, Hongzhi; Gao, Junping; Ma, Nan

    2017-02-23

    Flower opening is an important process in the life cycle of flowering plants and is influenced by various endogenous and environmental factors. Our previous work demonstrated that rose (Rosa hybrida) flowers are highly sensitive to dehydration during flower opening and the water recovery process after dehydration induced ethylene production rapidly in flower gynoecia. In addition, this temporal- and spatial-specific ethylene production is attributed to a transient but robust activation of the rose MAP KINASE6-ACC SYNTHASE1 (RhMPK6-RhACS1) cascade in gynoecia. However, the upstream component of RhMPK6-RhACS1 is unknown, although RhMKK9 (MAP KINASE KINASE9), a rose homologue of Arabidopsis MKK9, could activate RhMPK6 in vitro. In this study, we monitored RhMKK2/4/5/9 expression, the potential upstream kinase to RhMPK6, in rose gynoecia during dehydration and rehydration. We found only RhMKK9 was rapidly and strongly induced by rehydration. Silencing of RhMKK9 significantly decreased rehydration-triggered ethylene production. Consistently, the expression of several ethylene-responsive genes was down regulated in the petals of RhMKK9-silenced flowers. Moreover, we detected the DNA methylation level in the promoter and gene body of RhMKK9 by Chop-PCR. The results showed that rehydration specifically elevated the DNA methylation level on the RhMKK9 gene body, whereas it resulted in hypomethylation in its promoter. Our results showed that RhMKK9 possibly acts as the upstream component of the RhMKK9-RhMPK6-RhACS1 cascade and is responsible for water recovery-triggered ethylene production in rose gynoecia, and epigenetic DNA methylation is involved in the regulation of RhMKK9 expression by rehydration.

  15. Predecessor rain events over China's low-latitude highlands associated with Bay of Bengal tropical cyclones

    NASA Astrophysics Data System (ADS)

    Yuan, Junpeng; Zhao, Di; Yang, Ruowen; Yang, Hongfei

    2018-02-01

    A predecessor rain event (PRE) is defined as organized heavy rainfall that occurs far ahead of tropical cyclone (TC), yet directly associated with the deep tropical moisture originating from the TC vicinity. The PREs occurring over China's low-latitude highlands (CLLH) in association with Bay of Bengal TCs were investigated from 1981 to 2012. Results indicate that about 19% of Bay of Bengal TCs produces PRE. The PREs frequently occur when TCs are active in the northern Bay of Bengal with northeastward paths. The PREs are more likely to appear in the pre-monsoon and post-monsoon seasons, with peaks in May and October, respectively. The median lifetime of the PREs was approximately two days. The distances between PREs and parent TCs are ranged from 745 to 1849 km, with a median distance of 1118 km. Composite results of PREs suggested that deep moisture is advected from the TC vicinity to the remote CLLH region, which is situated beneath the equatorward entrance of the upper-level East Asia subtropical jet (EASJ). The lower-level southwesterly flow, which is associated with a strong pressure gradient between the western Pacific subtropical high and a trough in Bay of Bengal, steers TCs conveying abundant moisture from the Bay of Bengal to the CLLH region. The enhancement of the ascent and frontogenesis within the equatorward entrance region of the EASJ is favorable for occurrence of PREs in CLLH. TCs may also have a dynamical role in occurrence of PREs by intensifying the upper-level EASJ.

  16. Assessing the suitability of benthic foraminiferal morpho-groups to reconstruct paleomonsoon from Bay of Bengal

    NASA Astrophysics Data System (ADS)

    Manasa, M.; Saraswat, Rajeev; Nigam, Rajiv

    2016-04-01

    Temporal changes in benthic foraminiferal morpho-groups were suggested as an effective proxy to reconstruct past monsoon intensity from the Arabian Sea. Here, in order to test the applicability of temporal variation in morpho-groups to reconstruct past monsoon intensity from the Bay of Bengal, we have documented recent benthic foraminiferal distribution from the continental shelf region of the northwestern Bay of Bengal. Based on the external morphology, benthic foraminifera were categorized into rounded symmetrical (RSBF) and angular asymmetrical benthic foraminifera (AABF). Additionally, a few other dominant groups were also identified based on test composition (agglutinated, calcareous) and abundance (Asterorotalids and Nonions). The relative abundance of each group was compared with the ambient physico-chemical conditions, including dissolved oxygen, organic matter, salinity and temperature. We report that the RSBF are abundant in comparatively warm and well oxygenated waters of low salinity, suggesting a preference for high energy environment, whereas AABF dominate relatively cold, hypersaline deeper waters with low dissolved oxygen, indicating a low energy environment. The agglutinated foraminifera, Asterorotalids and Nonions dominate shallow water, low salinity regions, whereas the calcareous benthic foraminiferal abundance increases away from the riverine influx regions. Food availability, as estimated from organic carbon abundance in sediments, has comparatively less influence on faunal distribution in the northwestern Bay of Bengal, as compared to dissolved oxygen, temperature and salinity. We conclude that the factors associated with freshwater influx affect the distribution of benthic foraminiferal morpho-groups in the northwestern Bay of Bengal and thus it can be used to reconstruct past monsoon intensity from the Bay of Bengal.

  17. "Rose Blanche" in Translation

    ERIC Educational Resources Information Center

    Stan, Susan

    2004-01-01

    This comparative study focuses on three editions of "Rose Blanche," Roberto Innocenti's picturebook portrayal of a young girl who discovers a Nazi concentration camp on the outskirts of her German city. The original text, written in French by Christophe Gallaz to accompany Innocenti's illustrations, was translated into English and published in the…

  18. Modified developer increases line resolution in photosensitive resist

    NASA Technical Reports Server (NTRS)

    1965-01-01

    Standard developer solution is mixed with dipropyl carbonate. This reduces swelling in the photosensitive resist and permits application of relatively thick films with minimal pinhole formation and increased line resolution.

  19. Time-resolved luminescence measurements of the magnetic field effect on paramagnetic photosensitizers in photodynamic reactions

    NASA Astrophysics Data System (ADS)

    Mermut, O.; Bouchard, J.-P.; Cormier, J.-F.; Desroches, P.; Diamond, K. R.; Fortin, M.; Gallant, P.; Leclair, S.; Marois, J.-S.; Noiseux, I.; Morin, J.-F.; Patterson, M. S.; Vernon, M.

    2008-02-01

    The development of multimodal molecular probes and photosensitizing agents for use in photodynamic therapy (PDT) is vital for optimizing and monitoring cytotoxic responses. We propose a combinatorial approach utilizing photosensitizing molecules that are both paramagnetic and luminescent with multimodal functionality to perturb, control, and monitor molecular-scale reaction pathways in PDT. To this end, a time-domain single photon counting lifetime apparatus with a 400 nm excitation source has been developed and integrated with a variable low field magnet (0- 350mT). The luminescence lifetime decay function was measured in the presence of a sweeping magnetic field for a custom designed photosensitizing molecule in which photoinduced electron transfer was studied The photosensitizer studied was a donor-acceptor complex synthesized using a porphyrin linked to a fullerene molecule. The magneto-optic properties were investigated for the free-base photosensitizer complex as well as those containing either diamagnetic (paired electron) or paramagnetic (unpaired electron) metal centers, Zn(II) and Cu(II). The magnetic field was employed to affect and modify the spin states of radical pairs of the photosensitizing agents via magnetically induced hyperfine and Zeeman effects. Since the Type 1 reaction pathway of an excited triplet state photosensitizer involves the production of radical species, lifetime measurements were conducted at low dissolved oxygen concentration (0.01ppm) to elucidate the dependence of the magnetic perturbation on the photosensitization mechanistic pathway. To optimize the magnetic response, a solvent study was performed examining the dependence of the emission properties on the magnetic field in solutions of varying dielectric constants. Lastly, the cytotoxicity in murine tumor cell suspensions was investigated for the novel porphyrin-fullerene complex by inducing photodynamic treatments and determining the associated cell survival.

  20. Spreading tendencies of multiflora rose in the Southeast

    USGS Publications Warehouse

    Rosene, W.

    1950-01-01

    In 1948-49 studies were made on the spreading of multiflora rose at the sites of three old plantings in Alabama and Georgia. The age of these plantings varied from 14-40 years. Roses were invading surrounding land at each site. Observations indicated that seeds are carried by water and birds. Seedlings were numerous in drainageways leading from old shrubs. Birds had deposited seed under trees, in thickets, and along hedgerows. Seedlings growing under a single tree varied in number from a few to 50. Two rose bushes were found under a tree a mile from the probable point of origin. Seedlings were spreading in unimproved pastures by growing in thickets where they were protected from grazing and mowing. Plants were not found in cultivated fields. Spreading was similar near all three locations in like plant communities. Competition from trees affected multiflora more than that of any other type of vegetation. Plants thrive in pine woodlands with an open canopy, but growth is weak in a thick hardwood stand. Control will be necessary if multiflora rose is to be kept from spreading in idle land and unimproved pastures.

  1. Obituary: William K. Rose (1935-2010)

    NASA Astrophysics Data System (ADS)

    Trimble, Virginia

    2011-12-01

    Stellar astrophysicist William Kenneth Rose died near his home in Potomac, Maryland, on September 30, 2010, after an extended illness. Rose was the son of pharmacist Kenneth William Rose and Shirley Near Rose and was born in Ossining, New York, on August 10, 1935. He received an AB from Columbia College in 1957 and a PhD in physics from Columbia University in 1963, with a thesis on "measurements of linear polarization in discrete radio sources using a 9.4 cm maser," under the direction of Charles H. Townes. Rose played a major role in designing and constructing the maser and used it at a radio telescope at Maryland Point that belonged to the Naval Research Lab. He observed Jupiter and Saturn and a number of extra-solar-system sources, and also diffuse centimeter emission (see appendix). The thesis was not published in an archival journal, but can be found under Library of Congress code QB 475.R67. While in graduate School, Bill married Sheila Tuchman, whose primary scientific interests were biological. None of their three children chose to be scientists, but two are CPAs. Bill moved successfully through the academic hurdles) from a research position at Princeton (1963-67), where a collaboration with Nick Woolf and Martin Schwarzchild on the infrared spectra of giant stars became one of his most-cited papers, to assistant and associate professorships at MIT (1967-71), and then associate and full professorships at the University of Maryland (1971 to retirement in 2005). His most innovative work was probably that on nova explosions arising from degenerate ignition of hydrogen accreted on white dwarfs in close binary systems, published in 1968. The same idea occurred to others at about the same time, and Bill did not, perhaps, get quite his fair share of the credit. I first met Sheila and Bill in summer 1969 at the Stony Brook summer school on stellar evolution (not published until 1972). He lectured on the nature of nova explosions and on nuclear burning in thin

  2. Back to Hegel? On Gillian Rose's critique of sociological reason.

    PubMed

    Fuller, Brian W

    2017-08-22

    Thirty-five years ago, Gillian Rose articulated a significant critique of classical sociological reason, emphasizing its relationship to its philosophical forebears. In a series of works, but most significantly in her Hegel contra Sociology, Rose worked to specify the implications of sociology's failure, both in its critical Marxist and its 'scientific' forms, to move beyond Kant and to fully come to terms with the thought of Hegel. In this article, I unpack and explain the substance of her criticisms, developing the necessary Hegelian philosophical background on which she founded them. I argue that Rose's attempted recuperation of 'speculative reason' for social theory remains little understood, despite its continued relevance to contemporary debates concerning the nature and scope of sociological reason. As an illustration, I employ Rose to critique Chernilo's recent call for a more philosophically sophisticated sociology. From the vantage point of Rose, this particular account of a 'philosophical sociology' remains abstract and rooted in the neo-Kantian contradictions that continue to characterize sociology. © London School of Economics and Political Science 2017.

  3. Extended rhodamine photosensitizers for photodynamic therapy of cancer cells.

    PubMed

    Davies, Kellie S; Linder, Michelle K; Kryman, Mark W; Detty, Michael R

    2016-09-01

    Extended thio- and selenorhodamines with a linear or angular fused benzo group were prepared. The absorption maxima for these compounds fell between 640 and 700nm. The extended rhodamines were evaluated for their potential as photosensitizers for photodynamic therapy in Colo-26 cells. These compounds were examined for their photophysical properties (absorption, fluorescence, and ability to generate singlet oxygen), for their dark and phototoxicity toward Colo-26 cells, and for their co-localization with mitochondrial-specific agents in Colo-26 and HUT-78 cells. The angular extended rhodamines were effective photosensitizers toward Colo-26 cells with 1.0Jcm(-2) laser light delivered at λmax±2nm with values of EC50 of (2.8±0.4)×10(-7)M for sulfur-containing analogue 6-S and (6.4±0.4)×10(-8)M for selenium-containing analogue 6-Se. The linear extended rhodamines were effective photosensitizers toward Colo-26 cells with 5 and 10Jcm(-2) of broad-band light (EC50's⩽2.4×10(-7)M). Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. The (6-4) Dimeric Lesion as a DNA Photosensitizer.

    PubMed

    Vendrell-Criado, Victoria; Rodríguez-Muñiz, Gemma M; Lhiaubet-Vallet, Virginie; Cuquerella, M Consuelo; Miranda, Miguel A

    2016-07-04

    Based on our previous investigations into the photophysical properties of the 5-methyl-2-pyrimidone (Pyo) chromophore, we now extend our studies to the photobehavior of the dimeric (6-4) thymine photoproducts (6-4 PP) to evaluate their capability to act as instrinsic DNA photosensitizers. The lesion presents significant absorption in the UVB/UVA region, weak fluorescence emission, a singlet-excited-state energy of approximately 351 kJ mol(-1) , and a triplet-excited-state energy of 297 kJ mol(-1) . Its triplet transient absorption has a maximum at 420-440 nm, a lifetime of around 7 μs, and a high formation quantum yield, ΦISC =0.86. This species is efficiently quenched by thymidine. Its DNA photosensitizing properties are demonstrated by a series of experiments run on a pBR322 plasmid. The lesion photoinduces both single-strand breaks and the formation of cyclobutane thymine dimers. Altogether, these results show that, the substitution of the pyrimidone ring at C4 by a 5-hydroxy-5,6-dihydrothymine does not cancel out the photosensitization properties of the chromophore. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Variability of resistance in Black Bengal goats naturally infected with Haemonchus contortus.

    PubMed

    Kumar, Ratnesh; Ranjan, Sanjeev; Vishnu, P Guru; Negi, Mamta; Senapati, P K; Charita, V Gnani

    2015-03-01

    A total 290 Black Bengal goats (6 buck, 109 doe and 175 kids born from 11 sires) were studied to evaluate the variability of resistance in Black Bengal goats naturally infected with Haemonchus contortus. The variability of resistance in Black Bengal goat was studied for both genetic and non-genetic factors like village, sex, age dam, sire, dam resistance group and offspring resistance group. Male kids have slightly higher resistance than female kids although it was not significant. Resistance of kids was increased as age increases and kid population showed significantly different resistance status among the offspring resistant groups. The doe population showed significantly different LEPG as per the resistance group in all the collections. The present study found that the resistance of kids under sire were varied significantly and observed that the kids under sire 1, 6-8 were significantly more resistant than the kids of the sire 2, 5 and 11 in 3rd collection and it is also noticed that maternal genetic effect has a very little impact on resistance of kids. Males (buck) were most resistant and the kids were least resistant and the resistance of dam was in between the male and kids population.

  6. PLANT VOLATILES. Biosynthesis of monoterpene scent compounds in roses.

    PubMed

    Magnard, Jean-Louis; Roccia, Aymeric; Caissard, Jean-Claude; Vergne, Philippe; Sun, Pulu; Hecquet, Romain; Dubois, Annick; Hibrand-Saint Oyant, Laurence; Jullien, Frédéric; Nicolè, Florence; Raymond, Olivier; Huguet, Stéphanie; Baltenweck, Raymonde; Meyer, Sophie; Claudel, Patricia; Jeauffre, Julien; Rohmer, Michel; Foucher, Fabrice; Hugueney, Philippe; Bendahmane, Mohammed; Baudino, Sylvie

    2015-07-03

    The scent of roses (Rosa x hybrida) is composed of hundreds of volatile molecules. Monoterpenes represent up to 70% percent of the scent content in some cultivars, such as the Papa Meilland rose. Monoterpene biosynthesis in plants relies on plastid-localized terpene synthases. Combining transcriptomic and genetic approaches, we show that the Nudix hydrolase RhNUDX1, localized in the cytoplasm, is part of a pathway for the biosynthesis of free monoterpene alcohols that contribute to fragrance in roses. The RhNUDX1 protein shows geranyl diphosphate diphosphohydrolase activity in vitro and supports geraniol biosynthesis in planta. Copyright © 2015, American Association for the Advancement of Science.

  7. A palladium label to monitor nanoparticle-assisted drug delivery of a photosensitizer into tumor spheroids by elemental bioimaging.

    PubMed

    Niehoff, Ann-Christin; Moosmann, Aline; Söbbing, Judith; Wiehe, Arno; Mulac, Dennis; Wehe, Christoph A; Reifschneider, Olga; Blaske, Franziska; Wagner, Sylvia; Sperling, Michael; von Briesen, Hagen; Langer, Klaus; Karst, Uwe

    2014-01-01

    In this study, the cellular uptake of the second generation photosensitizer 5,10,15,20-tetrakis(3-hydroxyphenyl)porphyrin (mTHPP) was investigated using laser ablation coupled to inductively coupled plasma mass spectrometry (LA-ICP-MS) at a spatial resolution of 10 μm. To achieve high sensitivity, the photosensitizer was tagged with palladium. As a tumor model system, a 3D cell culture of the TKF-1 cell line was used. These tumor spheroids were incubated with the Pd-tagged photosensitizer embedded in poly(lactic-co-glycolic acid) (PLGA) nanoparticles to investigate the efficiency of nanoparticle based drug delivery. An accumulation of the drug in the first cell layers of the tumor spheroid was observed. In the case of nanoparticle based drug delivery, a significantly more homogeneous distribution of the photosensitizer was achieved, compared to tumor spheroids incubated with the dissolved photosensitizer without the nanoparticular drug delivery system. The infiltration depth of the Pd-tagged photosensitizer could not be increased with rising incubation time, which can be attributed to the adsorption of the photosensitizer onto cellular components.

  8. Uptake of photosensitizers by bacteria is influenced by the presence of cations

    NASA Astrophysics Data System (ADS)

    Kishen, A.; George, S.

    2007-05-01

    This investigation studies the influence of cations on photosensitizer uptake by Enterococcus faecalis (gram positive) and Actinobacillus actinomycetemcomitans (gram negative). Methods- The uptake of Methylene blue (MB) and Indocyanine Green (ICG), by bacteria were studied under the influence of divalent cations (CaCl II & MgCl II) and EDTA. Further, E. faecalis cells subjected to trypsinisation and calcium channel blocker (verapamil) were also analysed for MB and ICG uptake inorder to understand the mechanism of photosensitizer uptake. Results- Uptake of ICG was enhanced in the presence of divalent cations in E. faecalis and A. actinomycetemcomitans. Treating cells with EDTA had no significant effect on the photosensitizer uptake, although the highest concentration tested showed an enhancement of uptake. In contrast to ICG, MB showed a decreased uptake by bacterial cells on subjecting them to divalent cations and EDTA. Calcium channel blocker had no significant inhibitory effect on photosensitizers uptake. However, trypsin treatment resulted in significant reduction of ICG uptake. The result suggested that ICG uptake by bacteria is mediated through specific transporter protein while MB is associated with the outer surface structures of bacterial cells.

  9. How predictive are photosensitive epilepsy models as proof of principle trials for epilepsy?

    PubMed

    Yuen, Eunice S M; Sims, John R

    2014-06-01

    Human photosensitive epilepsy models have been used as proof of principle (POP) trials for epilepsy. Photosensitive patients are exposed to intermittent photic stimulation and the reduction in sensitivity to the number of standard visual stimulation frequencies is used as an endpoint. The aim of this research was to quantify the predictive capabilities of photosensitive POP trials, through a survey of current literature. A literature search was undertaken to identify articles describing photosensitive POP trials. Minimally efficacious doses (MEDs) in epilepsy were compared to doses in the POP trials that produced 50-100% response (ED50-100). Ratios of these doses were calculated and summarised statistically. The search identified ten articles describing a total of 17 anti-epileptic drugs. Of these, data for both MED and ED50-100 were available for 13 anti-epileptic drugs. The average ratio of MED to ED50-100 was 0.95 (95% CI 0.60-1.30). The difference in MED to ED50-100 ratios between partial epilepsy (0.82) was not significantly different from that of generalised epilepsy (1.08) (p=0.51). Photosensitive POP trials are a useful tool to quantitatively predict efficacy in epilepsy, and can be useful as early and informative indicators in anti-epileptic drug discovery and development. Copyright © 2014 British Epilepsy Association. Published by Elsevier Ltd. All rights reserved.

  10. Prostaglandin E2 is critical for the development of niacin-deficiency-induced photosensitivity via ROS production

    NASA Astrophysics Data System (ADS)

    Sugita, Kazunari; Ikenouchi-Sugita, Atsuko; Nakayama, Yasuko; Yoshioka, Haruna; Nomura, Takashi; Sakabe, Jun-Ichi; Nakahigashi, Kyoko; Kuroda, Etsushi; Uematsu, Satoshi; Nakamura, Jun; Akira, Shizuo; Nakamura, Motonobu; Narumiya, Shuh; Miyachi, Yoshiki; Tokura, Yoshiki; Kabashima, Kenji

    2013-10-01

    Pellagra is a photosensitivity syndrome characterized by three ``D's'': diarrhea, dermatitis, and dementia as a result of niacin deficiency. However, the molecular mechanisms of photosensitivity dermatitis, the hallmark abnormality of this syndrome, remain unclear. We prepared niacin deficient mice in order to develop a murine model of pellagra. Niacin deficiency induced photosensitivity and severe diarrhea with weight loss. In addition, niacin deficient mice exhibited elevated expressions of COX-2 and PGE syntheses (Ptges) mRNA. Consistently, photosensitivity was alleviated by a COX inhibitor, deficiency of Ptges, or blockade of EP4 receptor signaling. Moreover, enhanced PGE2 production in niacin deficiency was mediated via ROS production in keratinocytes. In line with the above murine findings, human skin lesions of pellagra patients confirmed the enhanced expression of Ptges. Niacin deficiency-induced photosensitivity was mediated through EP4 signaling in response to increased PGE2 production via induction of ROS formation.

  11. Serological diagnosis of neurobrucellosis.

    PubMed Central

    Sanchez-Sousa, A; Torres, C; Campello, M G; Garcia, C; Parras, F; Cercenado, E; Baquero, F

    1990-01-01

    The presence of antibodies was determined in the serum and cerebrospinal fluid in six patients with neurobrucellosis using the Rose Bengal test, the microdilution agglutination test, and the Coombs' test. Four of the patients were followed up for more than three months. The Rose Bengal test and the microagglutination test were positive in cerebrospinal fluid in five of the six cases at some stage. The Coombs' test was positive in cerebrospinal fluid in every patient and in one was the only positive serological test. Cerebrospinal fluid positivity is not excluded by low titres or negative results of antibodies in the serum for any of the three methods. A Coombs' test or some equivalent must always be made on the cerebrospinal fluid to diagnose neurobrucellosis. PMID:2312754

  12. Volatile Ester Formation in Roses. Identification of an Acetyl-Coenzyme A. Geraniol/Citronellol Acetyltransferase in Developing Rose Petals1

    PubMed Central

    Shalit, Moshe; Guterman, Inna; Volpin, Hanne; Bar, Einat; Tamari, Tal; Menda, Naama; Adam, Zach; Zamir, Dani; Vainstein, Alexander; Weiss, David; Pichersky, Eran; Lewinsohn, Efraim

    2003-01-01

    The aroma of roses (Rosa hybrida) is due to more than 400 volatile compounds including terpenes, esters, and phenolic derivatives. 2-Phenylethyl acetate, cis-3-hexenyl acetate, geranyl acetate, and citronellyl acetate were identified as the main volatile esters emitted by the flowers of the scented rose var. “Fragrant Cloud.” Cell-free extracts of petals acetylated several alcohols, utilizing acetyl-coenzyme A, to produce the corresponding acetate esters. Screening for genes similar to known plant alcohol acetyltransferases in a rose expressed sequence tag database yielded a cDNA (RhAAT1) encoding a protein with high similarity to several members of the BAHD family of acyltransferases. This cDNA was functionally expressed in Escherichia coli, and its gene product displayed acetyl-coenzyme A:geraniol acetyltransferase enzymatic activity in vitro. The RhAAT1 protein accepted other alcohols such as citronellol and 1-octanol as substrates, but 2-phenylethyl alcohol and cis-3-hexen-1-ol were poor substrates, suggesting that additional acetyltransferases are present in rose petals. The RhAAT1 protein is a polypeptide of 458 amino acids, with a calculated molecular mass of 51.8 kD, pI of 5.45, and is active as a monomer. The RhAAT1 gene was expressed exclusively in floral tissue with maximum transcript levels occurring at stage 4 of flower development, where scent emission is at its peak. PMID:12692346

  13. Topical delivery of a preformed photosensitizer for photodynamic therapy of cutaneous lesions

    NASA Astrophysics Data System (ADS)

    Oleinick, Nancy L.; Kenney, Malcolm E.; Lam, Minh; McCormick, Thomas; Cooper, Kevin D.; Baron, Elma D.

    2012-02-01

    Photosensitizers for photodynamic therapy (PDT) are most commonly delivered to patients or experimental animals via intravenous injection. After initial distribution throughout the body, there can be some preferential accumulation within tumors or other abnormal tissue in comparison to the surrounding normal tissue. In contrast, the photosensitizer precursor, 5-aminolevulinic acid (ALA) or one of its esters, is routinely administered topically, and more specifically, to target skin lesions. Following metabolic conversion to protoporphyrin IX, the target area is photoilluminated, limiting peripheral damage and targeting the effective agent to the desired region. However, not all skin lesions are responsive to ALA-PDT. Topical administration of fully formed photosensitizers is less common but is receiving increased attention, and some notable advances with selected approved and experimental photosensitizers have been published. Our team has examined topical administration of the phthalocyanine photosensitizer Pc 4 to mammalian (human, mouse, pig) skin. Pc 4 in a desired formulation and concentration was applied to the skin surface at a rate of 5-10 μL/cm2 and kept under occlusion. After various times, skin biopsies were examined by confocal microscopy, and fluorescence within regions of interest was quantified. Early after application, images show the majority of the Pc 4 fluorescence within the stratum corneum and upper epidermis. As a function of time and concentration, penetration of Pc 4 across the stratum corneum and into the epidermis and dermis was observed. The data indicate that Pc 4 can be delivered to skin for photodynamic activation and treatment of skin pathologies.

  14. The Rosa genome provides new insights into the domestication of modern roses.

    PubMed

    Raymond, Olivier; Gouzy, Jérôme; Just, Jérémy; Badouin, Hélène; Verdenaud, Marion; Lemainque, Arnaud; Vergne, Philippe; Moja, Sandrine; Choisne, Nathalie; Pont, Caroline; Carrère, Sébastien; Caissard, Jean-Claude; Couloux, Arnaud; Cottret, Ludovic; Aury, Jean-Marc; Szécsi, Judit; Latrasse, David; Madoui, Mohammed-Amin; François, Léa; Fu, Xiaopeng; Yang, Shu-Hua; Dubois, Annick; Piola, Florence; Larrieu, Antoine; Perez, Magali; Labadie, Karine; Perrier, Lauriane; Govetto, Benjamin; Labrousse, Yoan; Villand, Priscilla; Bardoux, Claudia; Boltz, Véronique; Lopez-Roques, Céline; Heitzler, Pascal; Vernoux, Teva; Vandenbussche, Michiel; Quesneville, Hadi; Boualem, Adnane; Bendahmane, Abdelhafid; Liu, Chang; Le Bris, Manuel; Salse, Jérôme; Baudino, Sylvie; Benhamed, Moussa; Wincker, Patrick; Bendahmane, Mohammed

    2018-06-01

    Roses have high cultural and economic importance as ornamental plants and in the perfume industry. We report the rose whole-genome sequencing and assembly and resequencing of major genotypes that contributed to rose domestication. We generated a homozygous genotype from a heterozygous diploid modern rose progenitor, Rosa chinensis 'Old Blush'. Using single-molecule real-time sequencing and a meta-assembly approach, we obtained one of the most comprehensive plant genomes to date. Diversity analyses highlighted the mosaic origin of 'La France', one of the first hybrids combining the growth vigor of European species and the recurrent blooming of Chinese species. Genomic segments of Chinese ancestry identified new candidate genes for recurrent blooming. Reconstructing regulatory and secondary metabolism pathways allowed us to propose a model of interconnected regulation of scent and flower color. This genome provides a foundation for understanding the mechanisms governing rose traits and should accelerate improvement in roses, Rosaceae and ornamentals.

  15. Erythrocyte antioxidant protection of rose hips (Rosa spp.).

    PubMed

    Widén, C; Ekholm, A; Coleman, M D; Renvert, S; Rumpunen, K

    2012-01-01

    Rose hips are popular in health promoting products as the fruits contain high content of bioactive compounds. The aim of this study was to investigate whether health benefits are attributable to ascorbic acid, phenols, or other rose-hip-derived compounds. Freeze-dried powder of rose hips was preextracted with metaphosphoric acid and the sample was then sequentially eluted on a C(18) column. The degree of amelioration of oxidative damage was determined in an erythrocyte in vitro bioassay by comparing the effects of a reducing agent on erythrocytes alone or on erythrocytes pretreated with berry extracts. The maximum protection against oxidative stress, 59.4 ± 4.0% (mean ± standard deviation), was achieved when incubating the cells with the first eluted meta-phosphoric extract. Removal of ascorbic acid from this extract increased the protection against oxidative stress to 67.9 ± 1.9%. The protection from the 20% and 100% methanol extracts was 20.8 ± 8.2% and 5.0 ± 3.2%, respectively. Antioxidant uptake was confirmed by measurement of catechin by HPLC-ESI-MS in the 20% methanol extract. The fact that all sequentially eluted extracts studied contributed to protective effects on the erythrocytes indicates that rose hips contain a promising level of clinically relevant antioxidant protection.

  16. Inactivation of Bacillus cereus by Na-chlorophyllin-based photosensitization on the surface of packaging.

    PubMed

    Luksiene, Z; Buchovec, I; Paskeviciute, E

    2010-11-01

    This study was focused on the possibility to inactivate food-borne pathogen Bacillus cereus by Na-chlorophyllin (Na-Chl)-based photosensitization in vitro and after attachment to the surface of packaging material. Bacillus cereus in vitro or attached to the packaging was incubated with Na-Chl (7·5×10(-8) to 7·5×10(-5) mol l(-1) ) for 2-60min in phosphate buffer saline. Photosensitization was performed by illuminating cells under a light with a λ of 400nm and an energy density of 20mW cm(-2) . The illumination time varied 0-5min and subsequently the total energy dose was 0-6J cm(-2) . The results show that B. cereus vegetative cells in vitro or attached to the surface of packaging after incubation with 7·5×10(-7) mol l(-1) Na-Chl and following illumination were inactivated by 7log. The photoinactivation of B. cereus spores in vitro by 4log required higher (7·5×10(-6) mol l(-1) ) Na-Chl concentration. Decontamination of packaging material from attached spores by photosensitization reached 5log at 7·5×10(-5) mol l(-1) Na-Chl concentration. Comparative analysis of different packaging decontamination treatments indicates that washing with water can diminish pathogen population on the surface by <1log, 100ppm Na-hypochlorite reduces the pathogens about 1·7log and 200ppm Na-hypochlorite by 2·2log. Meanwhile, Na-Chl-based photosensitization reduces bacteria on the surface by 4·2 orders of magnitude. Food-borne pathogen B. cereus could be effectively inactivated (7log) by Na-Chl-based photosensitization in vitro and on the surface of packaging material. Spores are more resistant than vegetative cells to photosensitization-based inactivation. Comparison of different surface decontamination treatments indicates that Na-Chl-based photosensitization is much more effective antibacterial tool than washing with water or 200ppm Na-hypochlorite. Our data support the idea that Na-Chl-based photosensitization has great potential for future application as an environment

  17. Tocopherols in rose hips (Rosa spp.) during ripening.

    PubMed

    Andersson, Staffan C; Olsson, Marie E; Gustavsson, Karl-Erik; Johansson, Eva; Rumpunen, Kimmo

    2012-08-15

    Rose hips are used as a food ingredient and in health products. They are rich in various bioactive compounds such as carotenoids and vitamin C, but data on their vitamin E content (tocopherols and tocotrienols) are limited. In this study, four different species of Rosa were analysed for tocopherol and tocotrienol content during ripening in three different years. Only α- and γ-tocopherol were found in the fleshy parts of the rose hips, and the tocopherol content and vitamin E activity varied depending on date of harvesting, species and year. The amount of vitamin E activity differed between species of Rosa and years, whereas the changes during ripening were relatively small. The choice of species must be considered if tocopherol content is to be optimised when rose hips are used as a food ingredient. Copyright © 2012 Society of Chemical Industry.

  18. Intermolecular Structural Change for Thermoswitchable Polymeric Photosensitizer

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Park, Wooram; Park, Sin-Jung; Cho, Soojeong

    2016-08-17

    A switchable photosensitizer (PS), which can be activated at a spe-cific condition beside light, has tremendous advantages for photo-dynamic therapy (PDT). Herein, we developed a thermo-switchable polymeric photosensitizer (T-PPS) by conjugating PS (Pheophor-bide-a, PPb-a) to a temperature-responsive polymer backbone of biocompatible hydroxypropyl cellulose (HPC). Self-quenched PS molecules linked in close proximity by pi-pi stacking in T-PPS were easily transited to an active monomeric state by the tempera-ture induced phase transition of polymer backbones. The tempera-ture responsive inter-molecular interaction changes of PS molecules in T-PPS were demonstrated in synchrotron small-angle X-ray scattering (SAXS) and UV-Vis spectrophotometer analysis. The T-PPS allowed switchablemore » activation and synergistically enhanced cancer cell killing effect at the hyperthermia temperature (45 °C). Our developed T-PPS has the considerable potential not only as a new class of photomedicine in clinics but also as a biosensor based on temperature responsiveness.« less

  19. Optimization of Photosensitized Tryptophan Oxidation in the Presence of Dimegin-Polyvinylpyrrolidone-Chitosan Systems.

    PubMed

    Solovieva, Anna B; Kardumian, Valeria V; Aksenova, Nadezhda A; Belovolova, Lyudmila V; Glushkov, Mikhail V; Bezrukov, Evgeny A; Sukhanov, Roman B; Kotova, Svetlana L; Timashev, Peter S

    2018-05-23

    By the example of a model process of tryptophan photooxidation in the aqueous medium in the presence of a three-component photosensitizing complex (porphyrin photosensitizer-polyvinylpyrrolidone- chitosan, PPS-PVP-CT) in the temperature range of 20-40 °С, we have demonstrated a possibility of modification of such a process by selecting different molar ratios of the components in the reaction mixture. The actual objective of this selection is the formation of a certain PPS-PVP-CT composition in which PVP macromolecules would coordinate with PPS molecules and at the same time practically block the complex binding of PPS molecules with chitosan macromolecules. Such blocking allows utilization of the bactericidal properties of chitosan to a greater extent, since chitosan is known to depress the PPS photosensitizing activity in PPS-PVP-CT complexes when using those in photodynamic therapy (PDT). The optimal composition of photosensitizing complexes appears to be dependent on the temperature at which the PDT sessions are performed. We have analyzed the correlations of the effective rate constants of tryptophan photooxidation with the photophysical characteristics of the formed complexes.

  20. Stable powders made from photosensitive polycrystalline complexes of heterocyclic monomers and their polymers

    NASA Technical Reports Server (NTRS)

    Murphy, Oliver J. (Inventor); Hitchens, G. Duncan (Inventor); Hodko, Dalibor (Inventor)

    1999-01-01

    The present invention relates to a low electronic conductivity polymer composition having well dispersed metal granules, a stable powder made from photosensitive polycrystalline complexes of pyrrole, or its substituted derivatives and silver cations for making the polymer composition, and methods of forming the stable powder and polymer composition, respectively. A polycrystalline complex of silver and a monomer, such as pyrrole, its substituted derivatives or combinations thereof, is precipitated in the form of a stable photosensitive powder upon addition of the monomer to a solvent solution, such as toluene containing an electron acceptor. The photosensitive powder can be stored in the dark until needed. The powder may be dissolved in a solvent, cast onto a substrate and photopolymerized.

  1. Genetic (idiopathic) epilepsy with photosensitive seizures includes features of both focal and generalized seizures.

    PubMed

    Xue, Jiao; Gong, Pan; Yang, Haipo; Liu, Xiaoyan; Jiang, Yuwu; Zhang, Yuehua; Yang, Zhixian

    2018-04-19

    Clinically, some patients having genetic (idiopathic) epilepsy with photosensitive seizures were difficult to be diagnosed. We aimed to discuss whether the genetic (idiopathic) epilepsy with photosensitive seizures is a focal entity, a generalized entity or a continuum. Twenty-two patients with idiopathic epilepsies and photoconvulsive response (PCR) were retrospectively recruited. In the medical records, the seizure types included "generalized tonic-clonic seizures (GTCS)" in 15, "partial secondarily GTCS (PGTCS)" in 3, partial seizures (PS) in 3, myoclonic seizures in 2, eyelid myoclonus in one, and only febrile seizures in one. Seizure types of PCR included GTCS (1/22), PGTCS (6/22), PS (9/22), electrical seizures (ES) (3/22) and GTCS/PGTCS (3/22). Combined the medical history with PCR results, they were diagnosed as: idiopathic (photosensitive) occipital lobe epilepsy (I(P)OE) in 12, genetic (idiopathic) generalized epilepsy (GGE) in one, GGE/I(P)OE in 5, pure photosensitive seizure in one, and epilepsy with undetermined generalized or focal seizure in 3. So, the dichotomy between generalized and focal seizures might have been out of date regarding to pathophysiological advances in epileptology. To some extent, it would be better to recognize the idiopathic epilepsy with photosensitive seizures as a continuum between focal and generalized seizures.

  2. Photosensitized regeneration of carbonyl compounds from oximes.

    PubMed

    de Lijser, H J Peter; Fardoun, Fadia H; Sawyer, Jody R; Quant, Michelle

    2002-07-11

    [reaction: see text] Deprotection of oximes to their corresponding carbonyl compounds through the use of photosensitized electron-transfer reactions proceeds in reasonable to good yields. Better yields are obtained in nonpolar solvents and when triplet sensitizers are used. Preliminary mechanistic studies suggest the involvement of an iminoxyl radical.

  3. Photosensitivity enhancement of PLZT ceramics by positive ion implantation

    DOEpatents

    Land, Cecil E.; Peercy, Paul S.

    1983-01-01

    The photosensitivity of lead lanthanum zirconate titanate (PLZT) ceramic material used in high resolution, high contrast, and non-volatile photoferroelectric image storage and display devices is enhanced significantly by positive ion implantation of the PLZT near its surface. Implanted ions include H.sup.+, He.sup.+, Ne.sup.+, Ar.sup.+, as well as chemically reactive ions from Fe, Cr, and Al. The positive ion implantation advantageously serves to shift the absorption characteristics of the PLZT material from near-UV light to visible light. As a result, photosensitivity enhancement is such that the positive ion implanted PLZT plate is sensitive even to sunlight and conventional room lighting, such as fluorescent and incandescent light sources. The method disclosed includes exposing the PLZT plate to the positive ions at sufficient density, from 1.times.10.sup.12 to 1.times.10.sup.17, and with sufficient energy, from 100 to 500 KeV, to provide photosensitivity enhancement. The PLZT material may have a lanthanum content ranging from 5 to 10%, a lead zirconate content of 62 to 70 mole %, and a lead titanate content of 38 to 30%. The ions are implanted at a depth of 0.1 to 2 microns below the surface of the PLZT plate.

  4. Disease resistance breeding in rose: current status and potential of biotechnological tools.

    PubMed

    Debener, Thomas; Byrne, David H

    2014-11-01

    The cultivated rose is a multispecies complex for which a high level of disease protection is needed due to the low tolerance of blemishes in ornamental plants. The most important fungal diseases are black spot, powdery mildew, botrytis and downy mildew. Rose rosette, a lethal viral pathogen, is emerging as a devastating disease in North America. Currently rose breeders use a recurrent phenotypic selection approach and perform selection for disease resistance for most pathogen issues in a 2-3 year field trial. Marker assisted selection could accelerate this breeding process. Thus far markers have been identified for resistance to black spot (Rdrs) and powdery mildew and with the ability of genotyping by sequencing to generate 1000s of markers our ability to identify markers useful in plant improvement should increase exponentially. Transgenic rose lines with various fungal resistance genes inserted have shown limited success and RNAi technology has potential to provide virus resistance. Roses, as do other plants, have sequences homologous to characterized R-genes in their genomes, some which have been related to specific disease resistance. With improving next generation sequencing technology, our ability to do genomic and transcriptomic studies of the resistance related genes in both the rose and the pathogens to reveal novel gene targets to develop resistant roses will accelerate. Finally, the development of designer nucleases opens up a potentially non-GMO approach to directly modify a rose's DNA to create a disease resistant rose. Although there is much potential, at present rose breeders are not using marker assisted breeding primarily because a good suite of marker/trait associations (MTA) that would ensure a path to stable disease resistance is not available. As our genomic analytical tools improve, so will our ability to identify useful genes and linked markers. Once these MTAs are available, it will be the cost savings, both in time and money, that will

  5. Population Vulnerability to Biannual Cholera Outbreaks and Associated Macro-Scale Drivers in the Bengal Delta

    PubMed Central

    Akanda, Ali Shafqat; Jutla, Antarpreet S.; Gute, David M.; Sack, R. Bradley; Alam, Munirul; Huq, Anwar; Colwell, Rita R.; Islam, Shafiqul

    2013-01-01

    The highly populated floodplains of the Bengal Delta have a long history of endemic and epidemic cholera outbreaks, both coastal and inland. Previous studies have not addressed the spatio-temporal dynamics of population vulnerability related to the influence of underlying large-scale processes. We analyzed spatial and temporal variability of cholera incidence across six surveillance sites in the Bengal Delta and their association with regional hydroclimatic and environmental drivers. More specifically, we use salinity and flood inundation modeling across the vulnerable districts of Bangladesh to test earlier proposed hypotheses on the role of these environmental variables. Our results show strong influence of seasonal and interannual variability in estuarine salinity on spring outbreaks and inland flooding on fall outbreaks. A large segment of the population in the Bengal Delta floodplains remain vulnerable to these biannual cholera transmission mechanisms that provide ecologic and environmental conditions for outbreaks over large geographic regions. PMID:24019441

  6. An Efficient Composition for Bengal Lights

    NASA Astrophysics Data System (ADS)

    Comet, M.; Schreyeck, L.; Fuzellier, H.

    2002-01-01

    Fuel-oxidizer mixtures based on potassium chlorate or sodium chlorate are well known. These mixtures have interesting properties of deflagration and are often used in propellants. Drastic reactivity of alkaline chlorates with ammonium salts due to the formation of ammonium chlorate NH4ClO3, a very unstable salt, is famous. By analogy, we tested the reactivity of different molecules containing nitrogen atoms, and we found an efficient fuel-oxidizer composed of potassium chlorate and thiocarbamide. Impressive bengal lights of various colors can easily be achieved using this basic composition.

  7. Frequency domain, time-resolved and spectroscopic investigations of photosensitizers encapsulated in liposomal phantoms

    NASA Astrophysics Data System (ADS)

    Mermut, Ozzy; Bouchard, Jean-Pierre; Cormier, Jean-Francois; Diamond, Kevin R.; Noiseux, Isabelle; Vernon, Marcia L.; Patterson, Michael S.

    2007-07-01

    A broadband frequency domain fluorescence lifetime system (from ns to ms time scale) has been developed to study the photochemical and photodynamic behavior of model, well-controlled photosensitizer-encapsulating liposomes. Liposomes are known to be efficient and selective photosensitizer (PS) drug delivery vesicles, however, their chemical and physical effects on the photochemical properties of the photosensitizer have not been well characterized. The liposomes employed in this study (both blank and photosensitizer-complexed) were characterized to determine their: a) size distribution (dynamic light scattering), b) image (scanning electron microscope, confocal fluorescence microscopy), c) concentration of particles (flow cytometry), d) temperature-dependant phase transition behavior (differential scanning calorimetry, and e) spectrofluorescent spectrophotometric properties, e.g. aggregation, in the confined environment. The fluorescence decay behavior of two families of encapsulated photosensitizers, di-and tetrasulfonated metallophthalocyanines, and 2-(1-hexyloxyethyl)-2-devinyl pyropheophorbide (HPPH), has been examined as a function of the liposome's physical properties (size-scale, distribution and concentration of scatterer) and the impact of the photosensitizer spatial confinement determined. It is found that the achievable size range and distribution of the PS-liposomes is controlled by the chemical nature of the PS for large liposomes (1000 nm), and is PS independent for small PS-liposomes (~140nm). The lifetime decay behavior was studied for all three photosensitizer-liposome systems and compared before and after confinement. We found the nature of the decay to be similar before and after encapsulation for the sulfonated phthalocyanines containing ionic moieties (primarily monoexponential) but not for HPPH. In the latter, the decay transitioned from multi- to monoexponential decay upon localizing lypophilic HPPH to the liposomal membrane. This behavior

  8. Photosensitized enzyme deactivation and protein oxidation by axial-substituted phosphorus(V) tetraphenylporphyrins.

    PubMed

    Ouyang, Dongyan; Hirakawa, Kazutaka

    2017-10-01

    The activity for photodynamic therapy of water-soluble cationic porphyrins, tetraphenylporphyrin P(V) complexes, was investigated. Bis(cyclohexylmethoxy)P(V)tetraphenylporphyrin (DCHMP(V)TPP), dichloroP(V)tetraphenylporphyrin (Cl 2 P(V)TPP), and dimethoxyP(V)tetraphenylporphyrin (DMP(V)TPP) could cause the photosensitized deactivation of tyrosinase. The tryptophan residue of human serum albumin (HSA) and several kinds of amino acids could be damaged by these P(V)porphyrins under visible light irradiation. The photosensitized damage of these biomolecules was inhibited by sodium azide, a singlet oxygen ( 1 O 2 ) quencher, and enhanced in deuterium oxide, suggesting the contribution of 1 O 2 . However, an excess amount of sodium azide did not completely inhibit the photosensitized damage. In addition, the redox potential measurements demonstrated the possibility of electron transfer from tryptophan and tyrosine to photoexcited P(V)porphyrins. These results suggest that electron transfer-mediated oxidation of amino acids contributes to the photosensitized protein and amino acid damage by these P(V)porphyrins. Specifically, Cl 2 P(V)TPP showed the highest photodamaging activity in the P(V)porphyrins used in this study. Oxidized products of amino acids by photoexcited P(V)porphyrins were analyzed with a liquid chromatography-mass spectrometer. Because of the hypoxic condition of a tumor, photodynamic therapy through a 1 O 2 -mediated mechanism should be restricted, and the electron transfer-mediated mechanism may improve the photodynamic effect. In the cases of these P(V)porphyrins, redox potential is the most important factor for photosensitized protein and amino acid oxidation through photoinduced electron transfer. Copyright © 2017 Elsevier B.V. All rights reserved.

  9. Rosa L.: rose, briar

    Treesearch

    Susan E. Meyer

    2008-01-01

    The genus Rosa is found primarily in the North Temperate Zone and includes about 200 species, with perhaps 20 that are native to the United States (table 1). Another 12 to 15 rose species have been introduced for horticultural purposes and are naturalized to varying degrees. The nomenclature of the genus is in a state of flux, making it difficult to number the species...

  10. Role of polymer matrix on photo-sensitivity of CdSe polymer nanocomposites

    NASA Astrophysics Data System (ADS)

    Kaur, Ramneek; Tripathi, S. K.

    2018-04-01

    This paper reports the effect of three different polymer matrices (PVP, PMMA and PVK) and Ag doping on the photo-sensitivity of CdSe polymer nanocomposites. The results reveal that the photoconductivity is high for linear chain polymer nanocomposites as compared to aromatic ones with decreasing trend as: CdSe-PMMA > CdSe-PVP > CdSe-PVK. The large substituents or branches along the polymer backbone hinder the stacking sequences in CdSe-PVK nanocomposites resulting in lowest photoconductivity. On contrary, CdSe-PVK nanocomposite exhibit highest photosensitivity. The reason behind it is the low value of dark conductivity in CdSe-PVK nanocomposite and photoconductive PVK matrix. With Ag doping, no considerable effect on the value of photosensitivity has been observed. The obtained results indicate that the photo-conducting properties of these polymer nanocomposites can be tuned by using different polymer matrices.

  11. Photosensitive dopants for liquid noble gases

    DOEpatents

    Anderson, David F.

    1988-01-01

    In an ionization type detector for high energy radiation wherein the energy of incident radiation is absorbed through the ionization of a liquid noble gas and resulting free charge is collected to form a signal indicative of the energy of the incident radiation, an improvement comprising doping the liquid noble gas with photosensitive molecules to convert scintillation light due to recombination of ions, to additional free charge.

  12. Design of a Model Execution Framework: Repetitive Object-Oriented Simulation Environment (ROSE)

    NASA Technical Reports Server (NTRS)

    Gray, Justin S.; Briggs, Jeffery L.

    2008-01-01

    The ROSE framework was designed to facilitate complex system analyses. It completely divorces the model execution process from the model itself. By doing so ROSE frees the modeler to develop a library of standard modeling processes such as Design of Experiments, optimizers, parameter studies, and sensitivity studies which can then be applied to any of their available models. The ROSE framework accomplishes this by means of a well defined API and object structure. Both the API and object structure are presented here with enough detail to implement ROSE in any object-oriented language or modeling tool.

  13. Photosensitive filler minimizes internal stresses in epoxy resins

    NASA Technical Reports Server (NTRS)

    Dillon, J. N.

    1967-01-01

    Photosensitive filler is added to curable epoxy resins to minimize stress from internal shrinkage during curing or polymerization. Cinnamic acid resins and cinnamal ketones may be added in the amount of 1 to 3 percent by weight of the resin mixture.

  14. Characterizing and identifying black spot resistance genes in polyploid roses

    USDA-ARS?s Scientific Manuscript database

    The ornamental quality of outdoor grown roses (Rosa hybrida) is under constant threat from foliar diseases, such as black spot caused by Diplocarpon rosae. Fungicides are primarily used to manage black spot; however, there is a high consumer demand for disease resistant roses which eliminate the nee...

  15. Photosensitized cleavage of some olefins as potential linkers to be used in drug delivery

    NASA Astrophysics Data System (ADS)

    Dinache, Andra; Smarandache, Adriana; Simon, Agota; Nastasa, Viorel; Tozar, Tatiana; Pascu, Alexandru; Enescu, Mironel; Khatyr, Abderrahim; Sima, Felix; Pascu, Mihail-Lucian; Staicu, Angela

    2017-09-01

    A study of photosensitized cleavage of different olefins as potential linkers for drug carrier complexes is reported. The role of singlet oxygen and the kinetic rates for light induced reactions were estimated by time-resolved measurements of singlet oxygen phosphorescence (at 1270 nm) obtained via 532 nm pulse laser excitation of a photosensitizer. The mixture of each studied olefin with verteporfin (used as photosensitizer) were exposed to low energy visible radiation. The rate constants for singlet oxygen quenching by studied olefins were determined. The irradiated solutions were investigated by FTIR spectroscopy and potential photoproducts were suggested. The experimental results were compared with simulations made by DFT method.

  16. Distribution of Heavy Metals in Surface Sediments of the Bay of Bengal Coast

    PubMed Central

    Hasan, M. R.; Khan, M.; Aktar, S.; Fatema, K.

    2017-01-01

    The concentrations of major (Si, Al, Ca, Fe, and K) and minor (Cd, Mn, Ni, Pb, U, Zn, Co, Cr, As, Cu, Rb, Sr, and Zr,) elements in the surficial sediments were studied in an attempt to establish their concentration in the Bengal coast. It was revealed that the majority of the trace elements have been introduced into the Bengal marine from the riverine inflows that are also affected by the impact of industrial, ship breaking yard, gas production plant, and urban wastes. The concentration of heavy metals was measured using Atomic Absorption Spectroscopy and Energy Dispersive X-ray fluorescence instruments. The highest concentrations for several trace elements were thus recorded which generally decrease with distance from the coast. It was observed that the heavy metal concentrations in the sediments generally met the criteria of international marine sediment quality. However, both the contamination factor and pollution load index values suggested the elevation of some metals' concentrations in the region. Constant monitoring of the Bengal coast water quality needs to be recorded with a view to minimizing the risk of health of the population and the detrimental impacts on the aquatic ecosystem. PMID:28255298

  17. Long-term Rebamipide and Diquafosol in Two Cases of Immune-Mediated Dry Eye

    PubMed Central

    Yamane, Mio; Ogawa, Yoko; Fukui, Masaki; Kamoi, Mizuka; Saijo-Ban, Yumiko; Yaguchi, Saori; Mukai, Shin; Kawakita, Tetsuya; Simmura, Shigeto; Tsubota, Kazuo

    2015-01-01

    ABSTRACT Purpose Two new drugs with mucin-inducing and secretion-promotive effects, rebamipide and diquafosol, were recently approved as topical dry-eye treatments. We report two cases in which the long-term use of mucin-inducing eye drops improved chronic ocular graft-versus-host disease (cGVHD)–related dry eye and ocular cicatricial pemphigoid (OCP)-like disease. Case Reports Case 1. A 61-year-old woman had cGVHD-related dry eye that resisted traditional medications. Next, we use topical diquafosol in addition to conventional treatments. The patient used diquafosol for 6 months without experiencing any side effects. The symptoms, including dry-eye sensation, ocular pain, foreign body sensation, and photophobia, as well as ocular surface findings including fluorescein and rose bengal scores and tear break-up time (TBUT), partly improved. To further improve the clinical signs and symptoms and decrease chronic inflammation, rebamipide was added to diquafosol. The symptoms, TBUT, and fluorescein and rose bengal scores markedly improved after long-term dual treatment without any side effects for 6 months. Case 2. A 77-year-old woman had OCP-like disease with dry eye. The patient did not improve using the currently available conventional treatments. Next, we use topical rebamipide in addition to conventional treatments. Symptoms including asthenopia, dry-eye sensation, ocular pain, and dull sensation, as well as fluorescein and rose bengal scores and TBUT, partly improved. Specifically, functional visual acuity was markedly improved after commencement of rebamipide. To further improve the clinical signs and symptoms and increase tear film stability and tear film volume, diquafosol was added to rebamipide. The combination of diquafosol and rebamipide worked for the patient. Improvements were seen in several symptoms, fluorescein and rose bengal scores, Schirmer test value, and TBUT without any side effects for 12 months. Conclusions Long-term treatment with topical

  18. Long-term rebamipide and diquafosol in two cases of immune-mediated dry eye.

    PubMed

    Yamane, Mio; Ogawa, Yoko; Fukui, Masaki; Kamoi, Mizuka; Saijo-Ban, Yumiko; Yaguchi, Saori; Mukai, Shin; Kawakita, Tetsuya; Simmura, Shigeto; Tsubota, Kazuo

    2015-04-01

    Two new drugs with mucin-inducing and secretion-promotive effects, rebamipide and diquafosol, were recently approved as topical dry-eye treatments. We report two cases in which the long-term use of mucin-inducing eye drops improved chronic ocular graft-versus-host disease (cGVHD)-related dry eye and ocular cicatricial pemphigoid (OCP)-like disease. Case 1. A 61-year-old woman had cGVHD-related dry eye that resisted traditional medications. Next, we use topical diquafosol in addition to conventional treatments. The patient used diquafosol for 6 months without experiencing any side effects. The symptoms, including dry-eye sensation, ocular pain, foreign body sensation, and photophobia, as well as ocular surface findings including fluorescein and rose bengal scores and tear break-up time (TBUT), partly improved. To further improve the clinical signs and symptoms and decrease chronic inflammation, rebamipide was added to diquafosol. The symptoms, TBUT, and fluorescein and rose bengal scores markedly improved after long-term dual treatment without any side effects for 6 months. Case 2. A 77-year-old woman had OCP-like disease with dry eye. The patient did not improve using the currently available conventional treatments. Next, we use topical rebamipide in addition to conventional treatments. Symptoms including asthenopia, dry-eye sensation, ocular pain, and dull sensation, as well as fluorescein and rose bengal scores and TBUT, partly improved. Specifically, functional visual acuity was markedly improved after commencement of rebamipide. To further improve the clinical signs and symptoms and increase tear film stability and tear film volume, diquafosol was added to rebamipide. The combination of diquafosol and rebamipide worked for the patient. Improvements were seen in several symptoms, fluorescein and rose bengal scores, Schirmer test value, and TBUT without any side effects for 12 months. Long-term treatment with topical rebamipide and diquafosol can improve dry eye

  19. Variability of intertidal foraminferal assemblages in a salt marsh, Oregon, USA

    USGS Publications Warehouse

    Milker, Yvonne; Horton, Benjamin P.; Nelson, Alan R.; Engelhart, Simon E.; Witter, Robert C.

    2015-01-01

    We studied 18 sampling stations along a transect to investigate the similarity between live (rose Bengal stained) foraminiferal populations and dead assemblages, their small-scale spatial variations and the distribution of infaunal foraminifera in a salt marsh (Toms Creek marsh) at the upper end of the South Slough arm of the Coos Bay estuary, Oregon, USA. We aimed to test to what extent taphonomic processes, small-scale variability and infaunal distribution influence the accuracy of sea-level reconstructions based on intertidal foraminifera. Cluster analyses have shown that dead assemblages occur in distinct zones with respect to elevation, a prerequisite for using foraminifera as sea-level indicators. Our nonparametric multivariate analysis of variance showed that small-scale spatial variability has only a small influence on live (rose Bengal stained) populations and dead assemblages. The dissimilarity was higher, however, between live (rose Bengal stained) populations in the middle marsh. We observed early diagenetic dissolution of calcareous tests in the dead assemblages. If comparable post-depositional processes and similar minor spatial variability also characterize fossil assemblages, then dead assemblage are the best modern analogs for paleoenvironmental reconstructions. The Toms Creek tidal flat and low marsh vascular plant zones are dominated by Miliammina fusca, the middle marsh is dominated by Balticammina pseudomacrescens and Trochammina inflata, and the high marsh and upland–marsh transition zone are dominated by Trochamminita irregularis. Analysis of infaunal foraminifera showed that most living specimens are found in the surface sediments and the majority of live (rose Bengal stained) infaunal specimens are restricted to the upper 10 cm, but living individuals are found to depths of 50 cm. The dominant infaunal specimens are similar to those in the corresponding surface samples and no species have been found living solely infaunally. The

  20. [Diagnosis of human brucellosis. Role of pH in the seroagglutination test and influence of pH on the agglutinating activity of IgM, IgG and IgA antibodies].

    PubMed

    Rubio Vallejo, Manuel; del Pozo, José L; Del Pozo León, José Luis; Hernández-Molina, Juan Manuel; Dorronsoro Ibero, Inés; Marrodán Ciordia, Teresa; Díaz García, Ramón

    2002-04-01

    To evaluate the role of pH in the seroagglutination test (SAT)and Rose Bengal (RB) test, and to determine the influence of pH on the agglutinating activity of IgM, IgG and IgA antibodies. The SAT was performed at pH 7.2 or pH 5.0 in standard microtiter-type polystyrene plates using Ring Test antigen or the Brucella suspension (BRUCAPT) provided in the Brucellacapt kits. Specific antibodies against native hapten were determined by radial immunodiffusion. Additionally, IgG, IgA and IgM fractions were separated from 8 sera by absorption chromatography and their agglutinating capacity was studied at pH 7.2 and 5.0. We studied 72 sera from patients with clinical brucellosis taken at the time of hospitalization, 16 from persons in contact with infected animals, and 16 from healthy donors. SAT results at pH 5.0 correlated with those obtained with the Rose Bengal test. Four Rose Bengal-positive sera were found to be SAT-negative at pH 7.2 and SAT-positive at pH 5.0. SAT performed at pH 5.0 with BRUCAPT antigen yielded higher titers than tests performed at pH 7.2 or 5.0 with Ring Test antigen (p < 0.001), with highest titers in IDR-positive sera. Among the 8 IgG fractions, all but one agglutinated at pH 7.2, and in 4, IgG titers showed significant increases at pH 5.0. Three IgA fractions were SAT-negative at pH 7.2 and SAT-positive at pH 5.0; the other 5 agglutinated at both pH conditions and were DTT-sensitive. All IgA fractions but one were positive by Rose Bengal. Agglutinating activity of the IgM fraction was not affected by pH. The SAT performed with the buffer and antigen suspension included in the Brucellacapt kit (pH 5.0) is highly useful for detecting agglutinating and non-agglutinating antibodies at pH 7.2.

  1. STS-54 Earth observation of a ship wake in the Bay of Bengal

    NASA Technical Reports Server (NTRS)

    1993-01-01

    STS-54 Earth observation taken aboard Endeavour, Orbiter Vehicle (OV) 105, is of a ship wake in the Bay of Bengal. The sun glint pattern on the ocean reveals many patterns of sea surface roughness related to currents, waves, wind roughening, and biology that and are not apparent when the ocean is viewed away from the sun's reflection. In this view of the Bay of Bengal, southeast of Madras, India, sun glint highlights convergence zones between ocean currents (bright, linear features), a eddy, and the wake of a ship. In several locations where the ship has passed areas of current shear, the ship wake is distorted, indicating the relative current direction.

  2. Hydroclimatic mechanisms of cholera transmission in the Bengal Delta

    NASA Astrophysics Data System (ADS)

    Tretkoff, Ernie

    2011-07-01

    Cholera, a deadly waterborne disease, remains a major threat in many areas of the world, including the Bengal Delta region. In this region, cholera outbreaks have two annual peaks; the first occurs during the dry season in the spring, and the second occurs in the fall following the wet season. However, the large-scale hydroclimatic processes underlying the propagation of the disease have not been well understood. Akanda et al. show that cholera outbreaks in the Bengal Delta region propagate from the coast to inland and from spring to fall following two distinct transmission cycles. The first outbreak begins in the spring near the coast when northward movement of plankton-rich seawater and increasing salinity promote the growth of cholera-causing bacteria in rivers, which are used for irrigation, sanitation, and consumption. The second outbreak begins in the fall, after summer floods and monsoons affect sanitation conditions that aid in bacterial transmission by contaminating waters over much of Bangladesh. (Water Resources Research, doi:10.1029/ 2010WR009914, 2011)

  3. 77 FR 15263 - Security Zone; Portland Rose Festival on Willamette River; Portland, OR

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-15

    ... Zone; Portland Rose Festival on Willamette River; Portland, OR AGENCY: Coast Guard, DHS. ACTION: Notice of enforcement of regulation. SUMMARY: The Coast Guard will enforce the Portland Rose Festival... Willamette River during the Portland Rose festival. During the enforcement period, no person or vessel may...

  4. New Generation of Photosensitizers: Conjugates of Chlorin e 6 With Diamond Nanoparticles

    NASA Astrophysics Data System (ADS)

    Lapina, V. A.; Bushuk, S. B.; Pavich, T. A.; Vorobey, A. V.

    2016-07-01

    Conjugates of chlorin e 6 with diamond nanoparticles were synthesized by two methods. The spectral and luminescent properties of the obtained conjugates were studied. It was shown that chlorin e 6 retained its photosensitizing activity in the conjugate. It was established that chlorin e 6 immobilized directly on diamond nanoparticles had higher photosensitizing activity than that conjugated using a spacer. It was observed that chlorin e 6 in the conjugate had higher photolytic stability than the free form.

  5. Epileptic spasms and early-onset photosensitive epilepsy in Patau syndrome: An EEG study.

    PubMed

    Spagnoli, Carlotta; Kugathasan, Umaiyal; Brittain, Helen; Boyd, Stewart G

    2015-08-01

    Patau syndrome, trisomy 13, is the third commonest autosomal trisomy. It is associated with a 25-50% prevalence of epilepsy, but detailed electroclinical descriptions are rare. The occurrence of early-onset photosensitivity has recently been reported in single patients. We collected electroclinical data on 8 infants (age range from 2 months to 3 years and 9 months, median: 17 months) with Patau syndrome referred for an EEG in our Clinical Neurophysiology Department between 1991 and 2011. All EEGs, case-notes, cytogenetic diagnosis and neuroimaging when available were reviewed; data on the occurrence of seizures, epileptiform discharges, photoparoxysmal response and their characteristics in terms of positive frequencies, latencies, grade and duration were noted and analysed. Two patients had been previously diagnosed with epilepsy (one with tonic spasms and one with multiple seizure types). We found 3 patients with photosensitive myoclonic epilepsy (37.5%), and one with non-photosensitive myoclonic epilepsy. We also recorded non-epileptic myoclonic jerks in one patient known to suffer from epileptic spasms. Among photosensitive patients we found self-limited, Waltz's grade 2-4, spike-wave/polyspike-wave discharges in low, medium and high frequency ranges in two patients and in the high frequency range in the third patient, with latencies and duration from less than 1s to a maximum of 9s. In our cohort of Patau syndrome patients, we found a high prevalence of spasms and photic-induced myoclonic jerks. Photosensitivity shows an unusual early age of onset. Copyright © 2014 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.

  6. Gene differentiation among ten endogamous groups of West Bengal, India.

    PubMed

    Chakraborty, R; Walter, H; Mukherjee, B N; Malhotra, K C; Sauber, P; Banerjee, S; Roy, M

    1986-11-01

    Ten endogamous populations of West Bengal, India have been surveyed for genetic variation in 12 systems. These populations encompass all social ranks in the caste hierarchy and cover almost the entire geographic area of the state. Gene diversity analysis suggests that these groups exhibit significant allele frequency variation at all but three loci. The overall genetic difference is not, however, in accord with the classification based on caste. Two low-ranking scheduled caste groups are, in fact, in close proximity with the high-caste ones, suggesting evidence of past generations of gene flow among them. Three different clusters of groups emerge from the present data, providing support for the anthropologic assertion that in Bengal Proto-Australoid, Caucasoid, and Mongoloid racial elements generally coexist. However, these three components are not uniformly present in all groups. Geographic separation of the groups is a strong determinant of the gene differentiation that exists among these populations.

  7. Singlet Oxygen Detection Using Red Wine Extracts as Photosensitizers.

    PubMed

    Lagunes, Irene; Vázquez-Ortega, Fernanda; Trigos, Ángel

    2017-09-01

    Moderate consumption of red wine provides beneficial effects to health. This is attributed to polyphenol compounds present in wine such as resveratrol, quercetin, gallic acid, rutin, and vanillic acid. The amount of these antioxidants is variable; nevertheless, the main beneficial effects of red wine are attributed to resveratrol. However, it has been found that resveratrol and quercetin are able to photosensitize singlet oxygen generation and conversely, gallic acid acts as quencher. Therefore, and since resveratrol and quercetin are some of the most important antioxidants reported in red wines, the aim of this research was to evaluate the photosensitizing ability of 12 red wine extracts through photo-oxidation of ergosterol. The presence of 1 O 2 was detected by ergosterol conversion into peroxide of ergosterol through 1 H NMR analysis. Our results showed that 10 wine extracts were able to act as photosensitizers in the generation of singlet oxygen. The presence of 1 O 2 can damage other compounds of red wine and cause possible organoleptic alterations. Finally, although the reaction conditions employed in this research do not resemble the inherent conditions in wine making processing or storing, or even during its consumption, this knowledge could be useful to prevent possible pro-oxidant effects and avoid detrimental effects in red wines. © 2017 Institute of Food Technologists®.

  8. Photosensitive TRPs.

    PubMed

    Hardie, Roger C

    2014-01-01

    The Drosophila "transient receptor potential" channel is the prototypical TRP channel, belonging to and defining the TRPC subfamily. Together with a second TRPC channel, trp-like (TRPL), TRP mediates the transducer current in the fly's photoreceptors. TRP and TRPL are also implicated in olfaction and Malpighian tubule function. In photoreceptors, TRP and TRPL are localised in the ~30,000 packed microvilli that form the photosensitive "rhabdomere"-a light-guiding rod, housing rhodopsin and the rest of the phototransduction machinery. TRP (but not TRPL) is assembled into multimolecular signalling complexes by a PDZ-domain scaffolding protein (INAD). TRPL (but not TRP) undergoes light-regulated translocation between cell body and rhabdomere. TRP and TRPL are also found in photoreceptor synapses where they may play a role in synaptic transmission. Like other TRPC channels, TRP and TRPL are activated by a G protein-coupled phospholipase C (PLCβ4) cascade. Although still debated, recent evidence indicates the channels can be activated by a combination of PIP2 depletion and protons released by the PLC reaction. PIP2 depletion may act mechanically as membrane area is reduced by cleavage of PIP2's bulky inositol headgroup. TRP, which dominates the light-sensitive current, is Ca(2+) selective (P Ca:P Cs >50:1), whilst TRPL has a modest Ca(2+) permeability (P Ca:P Cs ~5:1). Ca(2+) influx via the channels has profound positive and negative feedback roles, required for the rapid response kinetics, with Ca(2+) rapidly facilitating TRP (but not TRPL) and also inhibiting both channels. In trp mutants, stimulation by light results in rapid depletion of microvillar PIP2 due to lack of Ca(2+) influx required to inhibit PLC. This accounts for the "transient receptor potential" phenotype that gives the family its name and, over a period of days, leads to light-dependent retinal degeneration. Gain-of-function trp mutants with uncontrolled Ca(2+) influx also undergo retinal degeneration

  9. Fluorescence Imaging Assisted Photodynamic Therapy Using Photosensitizer-Linked Gold Quantum Clusters.

    PubMed

    Nair, Lakshmi V; Nazeer, Shaiju S; Jayasree, Ramapurath S; Ajayaghosh, Ayyappanpillai

    2015-06-23

    Fluorescence imaging assisted photodynamic therapy (PDT) is a viable two-in-one clinical tool for cancer treatment and follow-up. While the surface plasmon effect of gold nanorods and nanoparticles has been effective for cancer therapy, their emission properties when compared to gold nanoclusters are weak for fluorescence imaging guided PDT. In order to address the above issues, we have synthesized a near-infrared-emitting gold quantum cluster capped with lipoic acid (L-AuC with (Au)18(L)14) based nanoplatform with excellent tumor reduction property by incorporating a tumor-targeting agent (folic acid) and a photosensitizer (protoporphyrin IX), for selective PDT. The synthesized quantum cluster based photosensitizer PFL-AuC showed 80% triplet quantum yield when compared to that of the photosensitizer alone (63%). PFL-AuC having 60 μg (0.136 mM) of protoporphyrin IX was sufficient to kill 50% of the tumor cell population. Effective destruction of tumor cells was evident from the histopathology and fluorescence imaging, which confirm the in vivo PDT efficacy of PFL-AuC.

  10. Cell specific aptamer-photosensitizer conjugates as a molecular tool in photodynamic therapy

    PubMed Central

    Mallikaratchy, Prabodhika; Tang, Zhiwen

    2010-01-01

    This paper describes the application of a molecular construct of a photosensitizer and an aptamer for photo-therapeutically targeting tumor cells. The key step in increasing selectivity in chemotherapeutic drugs is to create effective molecular platforms that could target cancer cells but not normal cells. Recently, we have developed a strategy via cell-SELEX (Systematic Evolution of Ligands by Exponential Enrichment) to obtain cell specific aptamers using intact viable cells as targets to select aptamers that can recognize cell membrane proteins with high selectivity and excellent affinity. We have identified an aptamer TD05 that only recognizes Ramos cells, a Burkitt’s lymphoma cell line. Here, the high specificity of aptamers in target cell binding and an efficient phototherapy reagent, Ce6, are molecularly engineered to construct a highly selective Aptamer-photosensitizer conjugates (APS) to effectively destroy target cancer cells. Introduction of the APS conjugates followed by irradiation of light selectively destroyed target Ramos cells but not acute lymphoblastic leukemia and myeloid leukemia cell lines. This study demonstrates that the use of cancer specific aptamers conjugated to a photosensitizer will enhance the selectivity of photodynamic therapy. Coupled with the advantages of the cell-SELEX in generating multiple effective aptamers for diseased cell recognition, we will be able to develop highly efficient photosensitizer based therapeutical reagents for clinical applications. PMID:18058891

  11. Femi, Brake Mechanic: Kinesthetic Learning and Mike Rose's "Remedial" Education

    ERIC Educational Resources Information Center

    Martin, Tom

    2012-01-01

    Mike Rose, author of "The Mind at Work," extols both the wholesome, pragmatic qualities of handcraft and the implicit intellectual skills required of its practitioners. His recent article, "Rethinking Remedial Education and the Academic-Vocational Divide," is titled with a call to action; in these few words alone, Rose problematizes the polar…

  12. The influence of excitation radiation parameters on photosensitized generation of singlet oxygen in water

    NASA Astrophysics Data System (ADS)

    Il'ina, A. D.; Glazov, A. L.; Semenova, I. V.; Vasyutinskii, O. S.

    2016-06-01

    Photosensitized generation of singlet oxygen with the aid of Radahlorin® photosensitizer has been investigated. The dependences of the intensity of singlet oxygen phosphorescence and photosensitizer fluorescence on the excitation radiation wavelength in the range of 350-440 nm and on the irradiation dose have been obtained. The dependence of the ratio of the sensitizer fluorescence intensity at about 670 nm to the singlet oxygen phosphorescence intensity at a wavelength of 1270 nm on the excitation radiation wavelength is found to be nonmonotonic and have a minimum near the center of the absorption band on its red wing. The results obtained can be used to monitor the singlet oxygen concentration in solutions.

  13. Singlet Oxygen-Induced Membrane Disruption and Serpin-Protease Balance in Vacuolar-Driven Cell Death.

    PubMed

    Koh, Eugene; Carmieli, Raanan; Mor, Avishai; Fluhr, Robert

    2016-07-01

    Singlet oxygen plays a role in cellular stress either by providing direct toxicity or through signaling to initiate death programs. It was therefore of interest to examine cell death, as occurs in Arabidopsis, due to differentially localized singlet oxygen photosensitizers. The photosensitizers rose bengal (RB) and acridine orange (AO) were localized to the plasmalemma and vacuole, respectively. Their photoactivation led to cell death as measured by ion leakage. Cell death could be inhibited by the singlet oxygen scavenger histidine in treatments with AO but not with RB In the case of AO treatment, the vacuolar membrane was observed to disintegrate. Concomitantly, a complex was formed between a vacuolar cell-death protease, RESPONSIVE TO DESSICATION-21 and its cognate cytoplasmic protease inhibitor ATSERPIN1. In the case of RB treatment, the tonoplast remained intact and no complex was formed. Over-expression of AtSerpin1 repressed cell death, only under AO photodynamic treatment. Interestingly, acute water stress showed accumulation of singlet oxygen as determined by fluorescence of Singlet Oxygen Sensor Green, by electron paramagnetic resonance spectroscopy and the induction of singlet oxygen marker genes. Cell death by acute water stress was inhibited by the singlet oxygen scavenger histidine and was accompanied by vacuolar collapse and the appearance of serpin-protease complex. Over-expression of AtSerpin1 also attenuated cell death under this mode of cell stress. Thus, acute water stress damage shows parallels to vacuole-mediated cell death where the generation of singlet oxygen may play a role. © 2016 American Society of Plant Biologists. All Rights Reserved.

  14. Singlet Oxygen-Induced Membrane Disruption and Serpin-Protease Balance in Vacuolar-Driven Cell Death1[OPEN

    PubMed Central

    Carmieli, Raanan; Mor, Avishai; Fluhr, Robert

    2016-01-01

    Singlet oxygen plays a role in cellular stress either by providing direct toxicity or through signaling to initiate death programs. It was therefore of interest to examine cell death, as occurs in Arabidopsis, due to differentially localized singlet oxygen photosensitizers. The photosensitizers rose bengal (RB) and acridine orange (AO) were localized to the plasmalemma and vacuole, respectively. Their photoactivation led to cell death as measured by ion leakage. Cell death could be inhibited by the singlet oxygen scavenger histidine in treatments with AO but not with RB. In the case of AO treatment, the vacuolar membrane was observed to disintegrate. Concomitantly, a complex was formed between a vacuolar cell-death protease, RESPONSIVE TO DESSICATION-21 and its cognate cytoplasmic protease inhibitor ATSERPIN1. In the case of RB treatment, the tonoplast remained intact and no complex was formed. Over-expression of AtSerpin1 repressed cell death, only under AO photodynamic treatment. Interestingly, acute water stress showed accumulation of singlet oxygen as determined by fluorescence of Singlet Oxygen Sensor Green, by electron paramagnetic resonance spectroscopy and the induction of singlet oxygen marker genes. Cell death by acute water stress was inhibited by the singlet oxygen scavenger histidine and was accompanied by vacuolar collapse and the appearance of serpin-protease complex. Over-expression of AtSerpin1 also attenuated cell death under this mode of cell stress. Thus, acute water stress damage shows parallels to vacuole-mediated cell death where the generation of singlet oxygen may play a role. PMID:26884487

  15. Photodynamic therapy for inactivating endodontic bacterial biofilms and effect of tissue inhibitors on antibacterial efficacy

    NASA Astrophysics Data System (ADS)

    Shrestha, Annie; Kishen, Anil

    Complex nature of bacterial cell membrane and structure of biofilm has challenged the efficacy of antimicrobial photodynamic therapy (APDT) to achieve effective disinfection of infected root canals. In addition, tissue-inhibitors present inside the root canals are known to affect APDT activity. This study was aimed to assess the effect of APDT on bacterial biofilms and evaluate the effect of tissue-inhibitors on the APDT. Rose-bengal (RB) and methylene-blue (MB) were tested on Enterococcus faecalis (gram-positive) and Pseudomonas aeruginosa (gram-negative) biofilms. In vitro 7- day old biofilms were sensitized with RB and MB, and photodynamically activated with 20-60 J/cm2. Photosensitizers were pre-treated with different tissue-inhibitors (dentin, dentin-matrix, pulp tissue, bacterial lipopolysaccharides (LPS), and bovine serum albumin (BSA)) and tested for antibacterial effect of APDT. Microbiological culture based analysis was used to analyze the cell viability, while Laser Scanning Confocal Microscopy (LSCM) was used to examine the structure of biofilm. Photoactivation resulted in significant reduction of bacterial biofilms with RB and MB. The structure of biofilm under LSCM was found to be disrupted with reduced biofilm thickness. Complete biofilm elimination could not be achieved with both tested photosensitizers. APDT effect using MB and RB was inhibited in a decreasing order by dentin-matrix, BSA, pulp, dentin and LPS (P< 0.05). Both strains of bacterial biofilms resisted complete elimination after APDT and the tissue inhibitors existing within the root canal reduced the antibacterial activity at varying degrees. Further research is required to enhance the antibacterial efficacy of APDT in an endodontic environment.

  16. Cryptococcus neoformans capsule protects cell from oxygen reactive species generated by antimicrobial photodynamic inactivation

    NASA Astrophysics Data System (ADS)

    Prates, Renato Araujo; Hamblin, Michael R.; Kato, Ilka T.; Fuchs, Beth; Mylonakis, Eleytherios; Simões Ribeiro, Martha; Tegos, George

    2011-03-01

    Antimicrobial photodynamic inactivation (APDI) is based on the utilization of substances that can photosensitize biological tissues and are capable of being activated in the presence of light. Cryptococcus neoformans is an yeast surrounded by a capsule composed primarily of glucoronoxylomannan that plays an important role in its virulence. This yeast causes infection on skin, lungs and brain that can be associated with neurological sequelae and neurosurgical interventions, and its conventional treatment requires prolonged antifungal therapy, which presents important adverse effects. The aim of this study was to evaluate the protective effect of Cryptococcus neoformans capsule against reactive oxygen species generated by APDI. Cryptococcus neoformans KN99α, which is a strain able to produce capsule, and CAP59 that does not present capsule production were submitted to APDI using methylene blue (MB), rose bengal (RB), and pL-ce6 as photosensitizers (PS). Then microbial inactivation was evaluated by counting colony form units following APDI and confocal laser scanning microscopy (CLSM) illustrated localization as well as the preferential accumulation of PS into the fungal cells. C. neoformans KN99α was more resistant to APDI than CAP59 for all PSs tested. CLSM showed incorporation of MB and RB into the cytoplasm and a preferential uptake in mitochondria. A nuclear accumulation of MB was also observed. Contrarily, pL-ce6 appears accumulated in cell wall and cell membrane and minimal florescence was observed inside the fungal cells. In conclusion, the ability of C. neoformans to form capsule enhances survival following APDI.

  17. Using RNA-Seq to assemble a rose transcriptome with more than 13,000 full-length expressed genes and to develop the WagRhSNP 68k Axiom SNP array for rose (Rosa L.).

    PubMed

    Koning-Boucoiran, Carole F S; Esselink, G Danny; Vukosavljev, Mirjana; van 't Westende, Wendy P C; Gitonga, Virginia W; Krens, Frans A; Voorrips, Roeland E; van de Weg, W Eric; Schulz, Dietmar; Debener, Thomas; Maliepaard, Chris; Arens, Paul; Smulders, Marinus J M

    2015-01-01

    In order to develop a versatile and large SNP array for rose, we set out to mine ESTs from diverse sets of rose germplasm. For this RNA-Seq libraries containing about 700 million reads were generated from tetraploid cut and garden roses using Illumina paired-end sequencing, and from diploid Rosa multiflora using 454 sequencing. Separate de novo assemblies were performed in order to identify single nucleotide polymorphisms (SNPs) within and between rose varieties. SNPs among tetraploid roses were selected for constructing a genotyping array that can be employed for genetic mapping and marker-trait association discovery in breeding programs based on tetraploid germplasm, both from cut roses and from garden roses. In total 68,893 SNPs were included on the WagRhSNP Axiom array. Next, an orthology-guided assembly was performed for the construction of a non-redundant rose transcriptome database. A total of 21,740 transcripts had significant hits with orthologous genes in the strawberry (Fragaria vesca L.) genome. Of these 13,390 appeared to contain the full-length coding regions. This newly established transcriptome resource adds considerably to the currently available sequence resources for the Rosaceae family in general and the genus Rosa in particular.

  18. Impact of Photosensitizers Activation on Intracellular Trafficking and Viscosity

    PubMed Central

    Aubertin, Kelly; Bonneau, Stéphanie; Silva, Amanda K. A.; Bacri, Jean-Claude; Gallet, François; Wilhelm, Claire

    2013-01-01

    The intracellular microenvironment is essential for the efficiency of photo-induced therapies, as short-lived reactive oxygen species generated must diffuse through their intracellular surrounding medium to reach their cellular target. Here, by combining measurements of local cytoplasmic dissipation and active trafficking, we found that photosensitizers activation induced small changes in surrounding viscosity but a massive decrease in diffusion. These effects are the signature of a return to thermodynamic equilibrium of the system after photo-activation and correlated with depolymerization of the microtubule network, as shown in a reconstituted system. These mechanical measurements were performed with two intracellular photosensitizing chlorins having similar quantum yield of singlet oxygen production but different intracellular localizations (cytoplasmic for mTHPC, endosomal for TPCS2a). These two agents demonstrated different intracellular impact. PMID:24386423

  19. The Rose Art Museum Crisis

    ERIC Educational Resources Information Center

    Dillon, Paul

    2010-01-01

    On January 26, 2009, the Brandeis University Board of Trustees voted unanimously to close the Rose Art Museum (Waltham, Massachusetts). The proceeds from the subsequent auction were to be reinvested in the university to ensure its long-term financial health. The reaction to the decision by campus constituencies provides a case study to show the…

  20. STS-54 Earth observation of a ship wake in the Bay of Bengal

    NASA Image and Video Library

    1993-01-19

    STS054-72-056 (13-19 Jan 1993) --- A ship wake in the Bay of Bengal is noticeable in this 70mm frame. The sun glint pattern on the ocean reveals many patterns of sea surface roughness related to currents, waves, wind roughening, and biology that and are not apparent when the ocean is viewed away from the Sun's reflection. In this view of the Bay of Bengal, southeast of Madras, India, sun glint highlights convergence zones between ocean currents (bright, linear features), a eddy, and the wake of a ship. In several locations where the ship has passed areas of current shear, the ship wake is distorted, indicating the relative current direction.

  1. Synthesis of mesoscale, crumpled, reduced graphene oxide roses by water-in-oil emulsion approach

    NASA Astrophysics Data System (ADS)

    Sharma, Shruti; Pham, Viet H.; Boscoboinik, Jorge A.; Camino, Fernando; Dickerson, James H.; Tannenbaum, Rina

    2018-05-01

    Mesoscale crumpled graphene oxide roses (GO roses) were synthesized by using colloidal graphene oxide (GO) variants as precursors for a hybrid emulsification-rapid evaporation approach. This process produced rose-like, spherical, reduced mesostructures of colloidal GO sheets, with corrugated surfaces and particle sizes tunable in the range of ∼800 nm to 15 μm. Excellent reproducibility for particle size distribution is shown for each selected speed of homogenizer rotor among different sample batches. The morphology and chemical structure of these produced GO roses was investigated using electron microscopy and spectroscopy techniques. The proposed synthesis route provides control over particle size, morphology and chemical properties of the synthesized GO roses.

  2. Primary photosensitization in cattle caused by Froelichia humboldtiana.

    PubMed

    Souza, Paulo E C; Oliveira, Samuel S; Aguiar-Filho, Cristiano R; Cunha, Ana L B; Albuquerque, Raquel F; Evêncio-Neto, Joaquim; Riet-Correa, Franklin; Mendonça, Fábio S

    2012-12-01

    Three outbreaks of primary photosensitization caused by Froelichia humboldtiana are reported in the semiarid region of the states of Pernambuco and Paraíba, in northeastern Brazil. The disease occurred from March to June 2011, affecting 27 bovines out of a total of 70. The main lesions consisted of dermatitis of the white skin, with edema and necrosis. All the bovines recovered after removal from the areas invaded by F. humboldtiana. To produce the disease experimentally, one bovine with white skin was placed for 14 days into an area with F. humboldtiana as the sole forage. This bovine presented photodermatitis on the third day of consumption. The serum concentrations of total, indirect, and conjugated bilirubin and the serum activities of gamma-glutamyl transferase (GGT) and aspartate-aminotransferase (AST) in the spontaneously affected cattle and in the experimental cattle remained within normal ranges. It is concluded that F. humboldtiana causes primary photosensitization in cattle in northeastern Brazil. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. The Overnight Scentsation Rose Plant

    NASA Technical Reports Server (NTRS)

    1998-01-01

    International Flavors and Fragrances Inc., is a company that creates and manufactures flavors, fragrances and aroma chemicals. The Overnight Scentsation rose plant will be housed aboard NASA's shuttle flight STS-95 in a specially-designed structure under ultraviolet lights. The flowering plant was brought to Cape Canaveral from its home at IFF's greenhouse in Union Beach, New Jersey.

  4. Preclinical studies of vascular acting photosensitizer bacteriopheophorbide for the treatment of prostate cancer

    NASA Astrophysics Data System (ADS)

    Hetzel, Fred W.; Chen, Qun; Luck, David; Beckers, Jill; Huang, Zheng

    2004-06-01

    Photodynamic therapy (PDT) mediated with vascular acting photosensitizer pd-bacteriopheophorbide (Tookad), is investigated as an alternative modality for the total ablation of prostate cancer. In vivo normal canine prostate is used as the animal model. Interstitial PDT was performed by irradiating the surgically exposed prostates with a diode laser (763 nm, 150 mW/cm) to activate the IV infused photosensitizer drug. The prostate and its adjacent tissues were harvested and subjected to histopathological examination. At one-week post PDT, the animals recovered well with little or no urethral complications. Prostatic urethra and prostate adjacent tissues (bladder and underlying colon) were well preserved. PDT induced prostate lesions were characterized by marked hemorrhagic necrosis. Prostate lesions could be detected by MRI scan as early as 48 h post PDT. Maximum lesion size of 1.5 cm3 and 2.9 cm3 could be achieved at 50 J/cm and 100 J/cm, respectively, with interstitial treatment using a single 1-cm diffuser fiber, suggesting the Tookad-PDT is very effective in ablating prostatic tissue. Pharmacokinetic studies show that the photosensitizer is cleared rapidly from the circulation. In conclusion, the novel photosensitizer Tookad mediated PDT may provide an effective alternative to treat localized prostate cancer.

  5. The background state leading to arsenic contamination of Bengal basin groundwater.

    PubMed

    Adel, Miah M

    2005-12-01

    The Bengal basin has the world's densest water diversion constructions on the natural courses of rivers. The most damaging water diversion construction is the Farakka Barrage upon the international River Ganges. The diversion of water through this barrage and other constructions upstream of it has reduced the Ganges flow rate by 2.5 times. The resulting downstream effects are the depletion of surface water resources, more withdrawal than recharge of groundwater, sinking groundwater table, spread in depth and extension of the vadose zone, changes in surface features, climatic changes, etc. An investigation was carried out to find the contributions of water diversion to the arsenic contamination of groundwater in the Bengal basin. The reasonable scenario for arsenic contamination is the oxygen deficiency in groundwater and aeration of arsenopyrites buried in the sediment that would remain under water prior to 1975. The mineral forms water-soluble compounds of arsenic when react with atmospheric oxygen. These soluble arsenic compounds infiltrates to the groundwater. This article summarizes the short-time and incomplete study-based quick conclusions reached by investigators that have totally avoided the vital issue of water diversion. It then shows the depleting condition of the water resources under continuing diversions, the generation of favorable condition for arsenic release, the reasons for low sulfur concentration, the reason for first contamination in the Hugly basin, and the hindrance to water's self-purification. The articles advocates that the restoration of the virgin wetland ecosystems in the Bengal basin following the stoppage of the inordinate amount of unilateral upstream water withdrawals can remove the catastrophe.

  6. Carbon Dots as Versatile Photosensitizers for Solar-Driven Catalysis with Redox Enzymes.

    PubMed

    Hutton, Georgina A M; Reuillard, Bertrand; Martindale, Benjamin C M; Caputo, Christine A; Lockwood, Colin W J; Butt, Julea N; Reisner, Erwin

    2016-12-28

    Light-driven enzymatic catalysis is enabled by the productive coupling of a protein to a photosensitizer. Photosensitizers used in such hybrid systems are typically costly, toxic, and/or fragile, with limited chemical versatility. Carbon dots (CDs) are low-cost, nanosized light-harvesters that are attractive photosensitizers for biological systems as they are water-soluble, photostable, nontoxic, and their surface chemistry can be easily modified. We demonstrate here that CDs act as excellent light-absorbers in two semibiological photosynthetic systems utilizing either a fumarate reductase (FccA) for the solar-driven hydrogenation of fumarate to succinate or a hydrogenase (H 2 ase) for reduction of protons to H 2 . The tunable surface chemistry of the CDs was exploited to synthesize positively charged ammonium-terminated CDs (CD-NHMe 2 + ), which were capable of transferring photoexcited electrons directly to the negatively charged enzymes with high efficiency and stability. Enzyme-based turnover numbers of 6000 mol succinate (mol FccA) -1 and 43,000 mol H 2 (mol H 2 ase) -1 were reached after 24 h. Negatively charged carboxylate-terminated CDs (CD-CO 2 - ) displayed little or no activity, and the electrostatic interactions at the CD-enzyme interface were determined to be essential to the high photocatalytic activity observed with CD-NHMe 2 + . The modular surface chemistry of CDs together with their photostability and aqueous solubility make CDs versatile photosensitizers for redox enzymes with great scope for their utilization in photobiocatalysis.

  7. Raman tomography of Himalayan-derived muds (Bengal Shelf)

    NASA Astrophysics Data System (ADS)

    Borromeo, Laura; Andò, Sergio; Aliatis, Irene; France-Lanord, Christian; Garzanti, Eduardo

    2013-04-01

    Raman mineral analysis (RaMAn) is an innovative, efficient and user-friendly technique representing the ideal tool to perform provenance analysis of silt-sized sediments, which represent most of the sediment flux in river systems and the predominant grain size in large deltas and submarine fans (Andò et al., 2011). RaMAn allows in fact the reliable recognition of detrital grains down to 5 μm in size. The Ganga-Brahmaputra estuary in Bangladesh represents the largest single entry point of detritus in the world oceans. Between 1 and 2 billion tons of sediment each year has been reaching the Bengal Sea during most of the Neogene, feeding the world largest submarine fan (Goodbred and Kuehl, 2000; Galy and France-Lanord 2001). In order to detect the compositional differences between the fluvial environment (Garzanti et al., 2010; 2011) and the deep sea (Thompson, 1974; Yokohama et al., 1990) as well as the mineralogical variability associated with hydrodynamic sorting in the delta plain and proximal shelf, we have determined the mineralogical composition of largely Himalayan-derived muds deposited on the Bengal Shelf. Mineralogical analyses were carried out separately for four grain-size classes of 4 samples: (5-10 μm, 10-15 μm, 15-32 μm, >32 μm). Each class was separated into low-density (<2.90 g/cm3) and high-density fraction (>2.90 g/cm3) by centrifuging in sodium polytungstate and recovered by partial freezing with liquid nitrogen. Accurate quantitative mineralogical data were obtained by identifying at least 100 grains on each slide. RaMAn resulted to be essential for confident mineral identification, and helped us to reveal the nature of altered and opaque grains that cannot be identified under the optical microscope. Andò S.,Vignola P., Garzanti E., (2011). Raman counting: a new method to determine provenance of silt. Rendiconti Lincei, 22, Issue 4, pp 327-347; Galy A., France-Lanord C., (2001), Higher erosion rates in the Himalaya geochemical constraints

  8. The effect of UV exposure and heat treatment on crystallization behavior of photosensitive glasses

    NASA Astrophysics Data System (ADS)

    Kıbrıslı, Orhan; Ersundu, Ali Erçin

    2018-05-01

    In this study, photosensitive glasses in the Na2O-ZnO-Al2O3-SiO2 system with photosensitizing agents (cerium, silver, tin, antimony) and halogenides (NaF and KBr) were synthesized through a conventional melt-quenching technique. The crystallization mechanism was investigated for solely heat-treated and UV-exposed + heat-treated samples using differential thermal analysis (DTA), X-ray diffraction (XRD), energy-dispersive X-ray spectroscopy (EDS) and scanning electron microscopy (SEM) techniques to understand the effect of UV exposure on crystallization behavior of photosensitive glasses. Accordingly, non-isothermal DTA measurements were performed at different heating rates to determine crystallization peak, T p, and onset, T c, temperatures. For solely heat-treated samples, the kinetic parameters such as the Avrami constant, n, and morphology index, m, were calculated as 1 from the Ozawa method indicating surface crystallization and the value of crystallization activation energy was calculated as 944 kJ/mol using modified Kissinger method. On the contrary, bulk crystallization was found to be predominant for UV exposed + heat-treated samples revealing that UV exposure is the primary cause of bulk crystallization in photosensitive glasses.

  9. Isolation and characterization of the grain mold fungi, Cochliobolus and Alternaria spp., from sorghum using semi-selective media and DNA sequence analyses

    USDA-ARS?s Scientific Manuscript database

    Mold diseases, caused by fungal complexes including Alternaria, Cochliobolus and Fusarium species, limit sorghum grain production. Media were tested by plating Fusarium thapsinum, Alternaria sp. and Curvularia lunata, individually and competitively. Dichloran chloramphenicol rose bengal (DRBC) and m...

  10. Quenching-induced deactivation of photosensitizer by nanoencapsulation to improve phototherapy of cancer.

    PubMed

    Zeisser-Labouèbe, Magali; Mattiuzzo, Marc; Lange, Norbert; Gurny, Robert; Delie, Florence

    2009-09-01

    Photodynamic therapy has emerged as a promising alternative to current cancer treatment. However, conventional photosensitizers have several limitations due to their unsuitable pharmaceutical formulations and lack of selectivity. Our strategy was to exploit the advantages of nanoparticles and the quenching-induced deactivation of the model photosensitizer hypericin to produce "activatable" drug delivery systems. Efficient fluorescence and activity quenching were achieved by increasing the drug-loading rate of nanoparticles. In vitro assays confirmed the reversibility of hypericin deactivation, as the hypericin fluorescence and photodynamic activity were recovered upon cell internalization.

  11. Structural and functional alterations in rhodamine-123- and doxycycline-photosensitized cells

    NASA Astrophysics Data System (ADS)

    Shea, Christopher R.; Whitaker, Diana; Murphy, George F.; Chen, Norah; Wimberly, Joanne; Scholz, M.; Sherwood, M. E.; Flotte, Thomas J.; Hasan, Tayyaba

    1990-06-01

    In order to elucidate the mechanisms of photosensitized injury to mitochondria, two photosensitizers have been compared. Both doxycycline (DOTC) and rhodamine-l23 (R123) localize preferentially within the mitochondria of MGH-IJ1 bladder carcinoma cells j1 vitro, and both sensitize phototoxic injury that is selective for mitochondria. Mitochondria of cells pretreated with DOTC and irradiated with UVA (1 J/cm2, 320-400 rim) undergo massive swelling that begins by 10 mm after irradiation, is maximal by 1 h, and is partially repaired by 4 h; damage caused by exposure to a higher UVA dose (6 J/cm2), however, is not repaired. In contrast, cells pretreated with R123 and irradiated with an argon-ion laser (10 J/cm2, 514.5 rim) undergo a different type of mitochondrial injury, characterized by the delayed (4 h) onset of moderate mitochondrial swelling and striking mitochondrial distortion and fragmentation, which is not repaired by 48 h after irradiation. These differences indicate that the reactions underlying cellular phototoxicity can be distinguished even on an ultrastructural level. Probably both the primary photochemistry and the submitochondrial targets of these reactions differ with the two photosensitizers.

  12. Rose-K versus Soper contact lens in keratoconus: a randomized comparative trial.

    PubMed

    Gupta, Raghav; Sinha, Rajesh; Singh, Pooja; Sharma, Namrata; Tandon, Radhika; Titiyal, Jeewan S

    2014-01-01

    To perform a comparative evaluation of the efficacy and acceptability of Rose-K and Soper contact lenses in Keratoconus. Dr. Rajendra Prasad Center for Ophthalmic Sciences, All India Institute of Medical Sciences, New Delhi. A randomized comparative clinical trial was performed in keratoconic eyes fitted with Rose-K (Rose-K group) and Soper (Soper group) contact lenses. Patients data were evaluated for best spectacle corrected visual acuity, best contact lens corrected visual acuity (BCLCVA), corneal topography, glare acuity, contrast sensitivity, tear function tests and specular microscopy. Patients were also asked to complete a self-reported comfort questionnaire at each visit. Sixty eyes were randomized to the Rose-K and Soper groups. The two groups were comparable in all the baseline parameters. There was a statistically significant improvement in BCLCVA in both groups at 3 months (P < 0.01, both groups). The difference between in BCLCVA in both groups was not statistically significant. In both groups, there was a significant improvement in the comfort score at 3 months compared to baseline (P < 0.05, both group). The Rose-K group had statistically significantly better scores at 1 and 3 months compared with the Soper group (P = 0.006 and P < 0.001 respectively). Both groups were associated with a significant (P < 0.01), but comparable improvement in glare acuity at 3 months. There was a significant improvement in contrast sensitivity at 3 months in both groups (P < 0.01); the Rose-K group was significantly better than the Soper group at 1 and 3 months (P = 0.001 and 0.002 respectively). The mean number of trial lenses required for fitting Rose-K lens (2.00 ± 0.59) was significantly lower than the Soper lens (3.43 ± 0.82; P < 0.001). Both the contact lens designs provide an equal improvement in visual acuity in patients with Keratoconus. However, Rose-K contact lens provides greater comfort, better quality of vision and requires less chair time compared with

  13. Photoacoustic imaging of intravenously injected photosensitizer in rat burn models for efficient antibacterial photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Tsunoi, Yasuyuki; Sato, Shunichi; Ashida, Hiroshi; Terakawa, Mitsuhiro

    2012-02-01

    For efficient photodynamic treatment of wound infection, a photosensitizer must be distributed in the whole infected tissue region. To ensure this, depth profiling of a photosensitizer is necessary in vivo. In this study, we applied photoacoustic (PA) imaging to visualize the depth profile of an intravenously injected photosensitizer in rat burn models. In burned tissue, pharmacokinetics is complicated; vascular occlusion takes place in the injured tissue, while vascular permeability increases due to thermal invasion. In this study, we first used Evans Blue (EB) as a test drug to examine the feasibility of photosensitizer dosimetry based on PA imaging. On the basis of the results, an actual photosensitizer, talaporfin sodium was used. An EB solution was intravenously injected into a rat deep dermal burn model. PA imaging was performed on the wound with 532 nm and 610 nm nanosecond light pulses for visualizing vasculatures (blood) and EB, respectively. Two hours after injection, the distribution of EB-originated signal spatially coincided well with that of blood-originated signal measured after injury, indicating that EB molecules leaked out from the blood vessels due to increased permeability. Afterwards, the distribution of EB signal was broadened in the depth direction due to diffusion. At 12 hours after injection, clear EB signals were observed even in the zone of stasis, demonstrating that the leaked EB molecules were delivered to the injured tissue layer. The level and time course of talaporfin sodium-originated signals were different compared with those of EB-originated signals, showing animal-dependent and/or drug-dependent permeabilization and diffusion in the tissue. Thus, photosensitizer dosimetry should be needed before every treatment to achieve desirable outcome of photodynamic treatment, for which PA imaging can be concluded to be valid and useful.

  14. Who's behind that mask and cape? The Asian leopard cat's Agouti (ASIP) allele likely affects coat colour phenotype in the Bengal cat breed.

    PubMed

    Gershony, L C; Penedo, M C T; Davis, B W; Murphy, W J; Helps, C R; Lyons, L A

    2014-12-01

    Coat colours and patterns are highly variable in cats and are determined mainly by several genes with Mendelian inheritance. A 2-bp deletion in agouti signalling protein (ASIP) is associated with melanism in domestic cats. Bengal cats are hybrids between domestic cats and Asian leopard cats (Prionailurus bengalensis), and the charcoal coat colouration/pattern in Bengals presents as a possible incomplete melanism. The complete coding region of ASIP was directly sequenced in Asian leopard, domestic and Bengal cats. Twenty-seven variants were identified between domestic and leopard cats and were investigated in Bengals and Savannahs, a hybrid with servals (Leptailurus serval). The leopard cat ASIP haplotype was distinguished from domestic cat by four synonymous and four non-synonymous exonic SNPs, as well as 19 intronic variants, including a 42-bp deletion in intron 4. Fifty-six of 64 reported charcoal cats were compound heterozygotes at ASIP, with leopard cat agouti (A(P) (be) ) and domestic cat non-agouti (a) haplotypes. Twenty-four Bengals had an additional unique haplotype (A2) for exon 2 that was not identified in leopard cats, servals or jungle cats (Felis chaus). The compound heterozygote state suggests the leopard cat allele, in combination with the recessive non-agouti allele, influences Bengal markings, producing a darker, yet not completely melanistic coat. This is the first validation of a leopard cat allele segregating in the Bengal breed and likely affecting their overall pelage phenotype. Genetic testing services need to be aware of the possible segregation of wild felid alleles in all assays performed on hybrid cats. © 2014 The Authors. Animal Genetics published by John Wiley & Sons Ltd on behalf of Stichting International Foundation for Animal Genetics.

  15. High Probability of Cyclone Development in the Bay of Bengal

    NASA Image and Video Library

    2014-05-22

    The Joint Typhoon Warning Center states that formation of a significant tropical cyclone is possible in the Bay of Bengal within the next 12 - 24 hours as of 0730Z on May 21, 2014. Along with deep convective banding associated with a consolidating low-level circulation center, warm sea surface temperatures are conducive for further development. This image was taken by the Suomi NPP satellite's VIIRS instrument in two passes, the east pass around 0615Z and the west pass around 0755Z on May 21, 2014. Credit: NASA/NOAA/NPP/VIIRS The Joint Typhoon Warning Center states that formation of a significant tropical cyclone is possible in the Bay of Bengal within the next 12 - 24 hours as of 0730Z on May 21, 2014. Along with deep convective banding associated with a consolidating low-level circulation center, warm sea surface temperatures are conducive for further development. This image was taken by the Suomi NPP satellite's VIIRS instrument in two passes, the east pass around 0615Z and the west pass around 0755Z on May 21, 2014.

  16. Probing Photosensitization by Functionalized Carbon Nanotubes.

    PubMed

    Chen, Chia-Ying; Zepp, Richard G

    2015-12-01

    Carbon nanotubes (CNTs) photosensitize the production of reactive oxygen species that may damage organisms by biomembrane oxidation or mediate environmental transformations of CNTs. Photosensitization by derivatized carbon nanotubes from various synthetic methods, and thus with different intrinsic characteristics (e.g., diameter and electronic properties), has been investigated under environmentally relevant aquatic conditions. We used the CNT-sensitized photoisomerization of sorbic acid ((2E,4E)-hexa-2,4-dienoic acid) and singlet oxygen formation to quantify the triplet states ((3)CNT*) formed upon irradiation of selected single-walled carbon nanotubes (SWCNTs) and multiwalled carbon nanotubes (MWCNTs). The CNTs used in our studies were derivatized by carboxyl groups to facilitate their dispersion in water. Results indicate that high-defect-density (thus well-stabilized), small-diameter, and semiconducting-rich CNTs have higher-measured excited triplet state formation and therefore singlet oxygen ((1)O2) yield. Derivatized SWCNTs were significantly more photoreactive than derivatized MWCNTs. Moreover, addition of sodium chloride resulted in increased aggregation and small increases in (1)O2 production of CNTs. The most photoreactive CNTs exhibited comparable photoreactivity (in terms of (3)CNT* formation and (1)O2 yield) to reference natural organic matter (NOM) under sunlight irradiation with the same mass-based concentration. Selected reference NOM could therefore be useful in evaluating environmental photoreactivity or intended antibacterial applications of CNTs.

  17. Reuseable Objects Software Environment (ROSE): Introduction to Air Force Software Reuse Workshop

    NASA Technical Reports Server (NTRS)

    Cottrell, William L.

    1994-01-01

    The Reusable Objects Software Environment (ROSE) is a common, consistent, consolidated implementation of software functionality using modern object oriented software engineering including designed-in reuse and adaptable requirements. ROSE is designed to minimize abstraction and reduce complexity. A planning model for the reverse engineering of selected objects through object oriented analysis is depicted. Dynamic and functional modeling are used to develop a system design, the object design, the language, and a database management system. The return on investment for a ROSE pilot program and timelines are charted.

  18. In vivo quantification of photosensitizer concentration using fluorescence differential path-length spectroscopy: influence of photosensitizer formulation and tissue location

    NASA Astrophysics Data System (ADS)

    de Visscher, Sebastiaan A. H. J.; Witjes, Max J. H.; Kaščáková, Slávka; Sterenborg, Henricus J. C. M.; Robinson, Dominic J.; Roodenburg, Jan L. N.; Amelink, Arjen

    2012-06-01

    In vivo measurement of photosensitizer concentrations may optimize clinical photodynamic therapy (PDT). Fluorescence differential path-length spectroscopy (FDPS) is a non-invasive optical technique that has been shown to accurately quantify the concentration of Foscan® in rat liver. As a next step towards clinical translation, the effect of two liposomal formulations of mTHPC, Fospeg® and Foslip®, on FDPS response was investigated. Furthermore, FDPS was evaluated in target organs for head-and-neck PDT. Fifty-four healthy rats were intravenously injected with one of the three formulations of mTHPC at 0.15 mg kg-1. FDPS was performed on liver, tongue, and lip. The mTHPC concentrations estimated using FDPS were correlated with the results of the subsequent harvested and chemically extracted organs. An excellent goodness of fit (R2) between FDPS and extraction was found for all formulations in the liver (R2=0.79). A much lower R2 between FDPS and extraction was found in lip (R2=0.46) and tongue (R2=0.10). The lower performance in lip and in particular tongue was mainly attributed to the more layered anatomical structure, which influences scattering properties and photosensitizer distribution.

  19. The Rose (Rosa hybrida) NAC Transcription Factor 3 Gene, RhNAC3, Involved in ABA Signaling Pathway Both in Rose and Arabidopsis

    PubMed Central

    Lü, Peitao; Liu, Jitao; Gao, Junping; Zhang, Changqing

    2014-01-01

    Plant transcription factors involved in stress responses are generally classified by their involvement in either the abscisic acid (ABA)-dependent or the ABA-independent regulatory pathways. A stress-associated NAC gene from rose (Rosa hybrida), RhNAC3, was previously found to increase dehydration tolerance in both rose and Arabidopsis. However, the regulatory mechanism involved in RhNAC3 action is still not fully understood. In this study, we isolated and analyzed the upstream regulatory sequence of RhNAC3 and found many stress-related cis-elements to be present in the promoter, with five ABA-responsive element (ABRE) motifs being of particular interest. Characterization of Arabidopsis thaliana plants transformed with the putative RhNAC3 promoter sequence fused to the β-glucuronidase (GUS) reporter gene revealed that RhNAC3 is expressed at high basal levels in leaf guard cells and in vascular tissues. Moreover, the ABRE motifs in the RhNAC3 promoter were observed to have a cumulative effect on the transcriptional activity of this gene both in the presence and absence of exogenous ABA. Overexpression of RhNAC3 in A. thaliana resulted in ABA hypersensitivity during seed germination and promoted leaf closure after ABA or drought treatments. Additionally, the expression of 11 ABA-responsive genes was induced to a greater degree by dehydration in the transgenic plants overexpressing RhNAC3 than control lines transformed with the vector alone. Further analysis revealed that all these genes contain NAC binding cis-elements in their promoter regions, and RhNAC3 was found to partially bind to these putative NAC recognition sites. We further found that of 219 A. thaliana genes previously shown by microarray analysis to be regulated by heterologous overexpression RhNAC3, 85 are responsive to ABA. In rose, the expression of genes downstream of the ABA-signaling pathways was also repressed in RhNAC3-silenced petals. Taken together, we propose that the rose RhNAC3 protein

  20. The rose (Rosa hybrida) NAC transcription factor 3 gene, RhNAC3, involved in ABA signaling pathway both in rose and Arabidopsis.

    PubMed

    Jiang, Guimei; Jiang, Xinqiang; Lü, Peitao; Liu, Jitao; Gao, Junping; Zhang, Changqing

    2014-01-01

    Plant transcription factors involved in stress responses are generally classified by their involvement in either the abscisic acid (ABA)-dependent or the ABA-independent regulatory pathways. A stress-associated NAC gene from rose (Rosa hybrida), RhNAC3, was previously found to increase dehydration tolerance in both rose and Arabidopsis. However, the regulatory mechanism involved in RhNAC3 action is still not fully understood. In this study, we isolated and analyzed the upstream regulatory sequence of RhNAC3 and found many stress-related cis-elements to be present in the promoter, with five ABA-responsive element (ABRE) motifs being of particular interest. Characterization of Arabidopsis thaliana plants transformed with the putative RhNAC3 promoter sequence fused to the β-glucuronidase (GUS) reporter gene revealed that RhNAC3 is expressed at high basal levels in leaf guard cells and in vascular tissues. Moreover, the ABRE motifs in the RhNAC3 promoter were observed to have a cumulative effect on the transcriptional activity of this gene both in the presence and absence of exogenous ABA. Overexpression of RhNAC3 in A. thaliana resulted in ABA hypersensitivity during seed germination and promoted leaf closure after ABA or drought treatments. Additionally, the expression of 11 ABA-responsive genes was induced to a greater degree by dehydration in the transgenic plants overexpressing RhNAC3 than control lines transformed with the vector alone. Further analysis revealed that all these genes contain NAC binding cis-elements in their promoter regions, and RhNAC3 was found to partially bind to these putative NAC recognition sites. We further found that of 219 A. thaliana genes previously shown by microarray analysis to be regulated by heterologous overexpression RhNAC3, 85 are responsive to ABA. In rose, the expression of genes downstream of the ABA-signaling pathways was also repressed in RhNAC3-silenced petals. Taken together, we propose that the rose RhNAC3 protein

  1. Identification of singlet oxygen photosensitizes in lambs drinking water in an alveld risk area in West Norway.

    PubMed

    Tønnesen, Hanne Hjorth; Mysterud, Ivar; Karlsen, Jan; Skulberg, Olav M; Laane, Carl M M; Schumacher, Trond

    2013-02-05

    Alveld is a hepatogenous photosensitivity disorder in lambs. Although alveld has been known in Norway for more than 100years, there are still questions related to the cause of the disease. Phytoporphyrin has long been incriminated as the photosensitizer in hepatogenous photosensitivity diseases but previous findings suggest that the photosensitizing mechanism in alveld is more complex, possibly involving other co-factors. The current work investigates the presence of non-hepatogenous photosensitizers originating in lamb's drinking water from various sources. In addition samples of two of the predominent cyanobacteria found in a representative biofilm (i.e. aggregates of microbes) were identified and isolated in axenic (i.e. pure) cultures. Information from the absorption-, fluorescence emission-, and -excitation spectra and the action spectrum for the formation of singlet oxygen was combined in order to identify the chromophores responsible for the formation of singlet oxygen, e.g. phycocyanins from the cyanobacteria. The highest level of singlet oxygen formation was detected in lotic (i.e. flowing) water in the period consistent with the outbreak of the alveld disease in the area. Meteorological data indicate a warm and wet May with a high radiation exposure leading up to a colder and wet June with an even higher solar irradiance. The seasonal variation in the amount of photosensitizers in lamb's drinking water combined meteorological data can be important to predict the outbreak of alveld. Copyright © 2012 Elsevier B.V. All rights reserved.

  2. Gold nanocage-photosensitizer conjugates for dual-modal image-guided enhanced photodynamic therapy.

    PubMed

    Srivatsan, Avinash; Jenkins, Samir V; Jeon, Mansik; Wu, Zhijin; Kim, Chulhong; Chen, Jingyi; Pandey, Ravindra K

    2014-01-01

    We have demonstrated that gold nanocage-photosensitizer conjugates can enable dual image-guided delivery of photosensitizer and significantly improve the efficacy of photodynamic therapy in a murine model. The photosensitizer, 3-devinyl-3-(1'-hexyloxyethyl)pyropheophorbide (HPPH), was noncovalently entrapped in the poly(ethylene glycol) monolayer coated on the surface of gold nanocages. The conjugate is stable in saline solutions, while incubation in protein rich solutions leads to gradual unloading of the HPPH, which can be monitored optically by fluorescence and photoacoustic imaging. The slow nature of the release in turn results in an increase in accumulation of the drug within implanted tumors due to the passive delivery of gold nanocages. Furthermore, the conjugate is found to generate more therapeutic singlet oxygen and have a lower IC50 value than the free drug alone. Thus the conjugate shows significant suppression of tumor growth as compared to the free drug in vivo. Short-term study showed neither toxicity nor phenotypical changes in mice at therapeutic dose of the conjugates or even at 100-fold higher than therapeutic dose of gold nanocages.

  3. Mesozooplankton production, grazing and respiration in the Bay of Bengal: Implications for net heterotrophy

    NASA Astrophysics Data System (ADS)

    Fernandes, Veronica; Ramaiah, N.

    2016-03-01

    Mesozooplankton samples were collected from the mixed layer along a central (along 88°E) and a western transect in the Bay of Bengal during four seasons covered between 2001 and 2006 in order to investigate spatio-temporal variability in their biomass. At these stations, grazing and respiration rates were measured from live zooplankton hauled in from the surface during December 2005. Akin to the mesozooplankton "paradox" in the central and eastern Arabian Sea, biomass in the mixed layer was more or less invariant in the central and western Bay of Bengal, even as the chl a showed marginal temporal variation. By empirical equation, the mesozooplankton production rate calculated to be 70-246 mg C m- 2 d- 1 is on par with the Arabian Sea. Contrary to the conventional belief, mesozooplankton grazing impact was up to 83% on primary production (PP). Low PP coupled with very high zooplankton production (70% of PP) along with abundant bacterial production (50% of the PP; Ramaiah et al., 2009) is likely to render the Bay of Bengal net heterotrophic, especially during the spring intermonsoon. Greater estimates of fecal pellet-carbon egestion by mesozooplankton compared to the average particulate organic carbon flux in sediment traps, implies that much of the matter is recycled by heterotrophic communities in the mixed layer facilitating nutrient regeneration for phytoplankton growth. We also calculated that over a third of the primary production is channelized for basin-wide zooplankton respiration that accounts for 52 Mt C annually. In the current scenario of global warming, if low (primary) productive warm pools like the Bay of Bengal continue to be net heterotrophic, negative implications like enhanced emission of CO2 to the atmosphere, increased particulate flux to the deeper waters and greater utilization of dissolved oxygen resulting in expansion of the existing oxygen minimum zone are imminent.

  4. In Vitro Antimicrobial Photodynamic Therapy Against Trichophyton mentagrophytes Using New Methylene Blue as the Photosensitizer.

    PubMed

    López-Chicón, P; Gulías, Ò; Nonell, S; Agut, M

    2016-11-01

    Antimicrobial photodynamic therapy combines the use of a photosensitizing drug with light and oxygen to eradicate pathogens. Trichophyton mentagrophytes is a dermatophytic fungus able to invade the skin and keratinized tissues. We have investigated the use of new methylene blue as the photosensitizing agent for antimicrobial photodynamic therapy to produce the in vitro inactivation of T mentagrophytes. A full factorial design was employed to optimize the parameters for photoinactivation of the dermatophyte. The parameters studied were new methylene blue concentration, contact time between the photosensitizing agent and the fungus prior to light treatment, and the fluence of red light (wavelength, 620-645nm) applied. The minimum concentration of new methylene blue necessary to induce the death of all T. mentagrophytes cells in the initial suspension (approximate concentration, 10 6 colony forming units per milliliter) was 50μM for a fluence of 81J/cm 2 after a contact time of 10minutes with the photosensitizing-agent. Increasing the concentration to 100μM allowed the fluence to be decreased to 9J/cm 2 . Comparison of our data with other published data shows that the susceptibility of T. mentagrophytes to antimicrobial photodynamic therapy with new methylene blue is strain-dependent. New methylene blue is a photosensitizing agent that should be considered for the treatment of fungal skin infections caused by this dermatophyte. Copyright © 2016 AEDV. Publicado por Elsevier España, S.L.U. All rights reserved.

  5. 75 FR 20778 - Security Zone; Portland Rose Festival Fleet Week, Willamette River, Portland, OR

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-04-21

    ...-AA87 Security Zone; Portland Rose Festival Fleet Week, Willamette River, Portland, OR AGENCY: Coast... during the Portland Rose Festival Fleet Week from June 2, 2010, through June 7, 2010. The security zone... is a need to provide a security zone for the 2010 Portland Rose Festival Fleet Week, and there is...

  6. The survey and criterion of the compass rose in Chinese A-share market

    NASA Astrophysics Data System (ADS)

    Tian, Wenzhao; Wang, Yanxiang; Huo, Zhao; Li, Yilin

    2018-02-01

    The compass rose is one of the few "recurring patterns" found in financial markets. In this paper, the compass rose in Chinese A-share market is comprehensively investigated. It is newly discovered that among the 1331 A-shares, which had been listed for more than 15 years by the end of 2015, only about 20 show the compass rose. The outcome of the analysis shows that there exists a threshold of the ratio of the data points on main rays to all data points. Only when this ratio is above the threshold, the compass rose appears. The reasons why such a threshold exists, and its interrelationship with the data frequency and the tick/volatility ratio are analyzed.

  7. The Political Economy of English Education in Muslim Bengal: 1871-1912.

    ERIC Educational Resources Information Center

    Rahim, Aminur

    1992-01-01

    Examines explanations for lack of progress by Muslims in English education in East Bengal, colonial British India (now Bangladesh). Argues that urban-based, elitist English education failed to provide opportunities to rural Muslim farmers, and that, after the British formulated educational policies meeting Muslim needs, that community responded…

  8. New Photosensitized Processes at Aerosol and Ocean Surfaces

    NASA Astrophysics Data System (ADS)

    Rossignol, S.; Aregahegn, K. Z.; Ciuraru, R.; Bernard, F.; Tinel, L.; Fine, L.; George, C.

    2014-12-01

    From a few years now, there is a growing body of evidence that photoinduced processes could be of great importance for the tropospheric chemistry. Here, we would like to present two additional outcomes of this new area of research, firstly the photosensitized direct VOC uptake by aerosols and, secondly, the photoinduced chemical formation of unsaturated VOC from marine microlayer proxy. It was recently shown that the chemistry of glyoxal toward ammonium ions into droplets and wet aerosols leads to the formation of light-absorbing compounds. Among them, we found that imidazole-2-carboxaldehyde (IC) acts as a photosensitizer and is able to initiate the growth of organic aerosols via the uptake of VOC, such as limonene. Given its potential importance, the mechanism of this photoinduced uptake was investigated thanks to aerosol flow tube experiments and UPLC-ESI-HRMS analysis. Results reveal hydrogen abstraction on the VOC molecule by the triplet state of IC leading to the VOC oxidation without any traditional oxidant. As well as aerosol, the sea-surface microlayer, known to be enriched in light-absorbing organics, is largely impacted by photochemical processes. Recent studies have pointed out for example the role of photosentitized processes in the loss of NO2 and ozone at water surfaces containing photoactive compounds such as chlorophyll. In order to go further, we worked from sea-surface microlayer proxy containing humic acids as photoactive material and organic acids as surfactants. Beside oxidation processes, we monitored by high resolution PTR-MS the release in the gas phase of unsaturated compounds, including C5 dienes (isoprene ?). A strong correlation between the measured surface tension and the C5 diene concentration in the gas phase was evidenced, clearly pointing toward an interfacial process. This contribution will highlight the similarities between both systems and will attempt to present a general chemical scheme for photosensitized chemistry at

  9. Inhibiting the photosensitized oxidation of anthracene and tryptophan by means of natural antioxidants

    NASA Astrophysics Data System (ADS)

    Aksenova, N. A.; Vyzhlova, E. N.; Malinovskaya, V. V.; Parfenov, V. V.; Solov'eva, A. B.; Timashev, P. S.

    2013-08-01

    It is shown that model reactions of photosensitized oxidation of anthracene and tryptophan can be used for evaluation and comparison of antioxidant activity of various classes of compounds. Inhibition of the oxidation of substrates in the presence of the familiar antioxidants tocopherol (vitamin E), ascorbic acid (vitamin C), and mixtures of these vitamins with methionine, and in the presence of reputed antioxidants dihydroquercetin and taurine, are considered. It is concluded that all of the above compounds except for taurine have antioxidant properties; i.e., they reduce the rate constants of the photosensitized oxidation of anthracene and tryptophan. It is found that the inhibition of oxidation is associated with the interaction between antioxidants and singlet oxygen. Analysis of the kinetic dependences of the photosensitized oxidation of substrates in the presence of antioxidants reveals that a mixture of vitamins inhibits the process most efficiently, and inhibition occurs at the initial stages due to more active interaction between singlet oxygen and vitamin C

  10. Ozone in the marine boundary layer of Bay of Bengal and Arabian Sea during post winter period - continental influence

    NASA Astrophysics Data System (ADS)

    Nair, Prabha R.; George, Susan K.; David, Liji Mary; Parameswaran, Krishnaswamy

    Ozone plays a key role in controlling the oxidation capacity of the troposphere and hence the lifetime of a variety of trace gases in the atmosphere. In pristine marine boundary layer (MBL), entire chemistry is initiated by the photolysis of ozone and the subsequent formation of OH radical from water vapour. Also in such environment, photochemical destruction is considered as a major sink in global ozone budget. Even though large number of studies on near surface ozone has been carried out over land such studies are very few over oceanic environments. This paper presents the observational results on the spatial variations of near-surface ozone over Bay of Bengal and Arabian Sea as revealed by the cruise-based measurements (cruise No. SK223) conducted as part of Integrated Campaign for Aerosol gases and Radiation Budget (ICARB) under the Geosphere Biosphere Programme of Indian Space Research Organisation (IGBP). Online measurements of ozone have been carried out by using a UV Photometric Analyser (model 49C of Thermo Electron Corporation, USA). Ozone mixing ratio was observed to be significantly high over northern Bay of Bengal (20-28 ppb) compared to southern Bay of Bengal and Arabian Sea. Minimum levels of ozone ( 5 ppb) have been measured in the central Bay of Bengal region. Over Arabian Sea latitudinal variation was not prominently observed. The over all latitudinal gradient is estimated to be 1.2 ppb/o latitude over Bay of Bengal with longitudinal gradient showing variation depending on the latitude sector. It was maximum (of 1.2ppb/o longitude) over the mid Bay of Bengal region ( 15o N). Longitudinal variation was not significant over northern and southern regions. A close examination of surface airflow patterns and the air mass back trajectories revealed increase in ozone level associated with continental outflow from the northern and central parts of the subcontinent. The diurnal pattern also showed variations depending on the proximity to inhabited land

  11. Trace metal dynamics in zooplankton from the Bay of Bengal during summer monsoon.

    PubMed

    Rejomon, G; Kumar, P K Dinesh; Nair, M; Muraleedharan, K R

    2010-12-01

    Trace metal (Fe, Co, Ni, Cu, Zn, Cd, and Pb) concentrations in zooplankton from the mixed layer were investigated at 8 coastal and 20 offshore stations in the western Bay of Bengal during the summer monsoon of 2003. The ecotoxicological importance of trace metal uptake was apparent within the Bay of Bengal zooplankton. There was a distinct spatial heterogeneity of metals, with highest concentrations in the upwelling zones of the southeast coast, moderate concentrations in the cyclonic eddy of the northeast coast, and lowest concentrations in the open ocean warm gyre regions. The average trace metal concentrations (μg g⁻¹) in coastal zooplankton (Fe, 44894.1 ± 12198.2; Co, 46.2 ± 4.6; Ni, 62.8 ± 6.5; Cu, 84.9 ± 6.7; Zn, 7546.8 ± 1051.7; Cd, 46.2 ± 5.6; Pb, 19.2 ± 2.6) were higher than in offshore zooplankton (Fe, 3423.4 ± 681.6; Co, 19.5 ± 3.81; Ni, 25.3 ± 7.3; Cu, 29.4 ± 4.2; Zn, 502.3 ± 124.3; Cd, 14.3 ± 2.9; Pb, 3.2 ± 2.0). A comparison of average trace metal concentrations in zooplankton from the Bay of Bengal showed enrichment of Fe, Co, Ni, Cu, Zn, Cd, and Pb in coastal zooplankton may be related to metal absorption from primary producers, and differences in metal concentrations in phytoplankton from coastal waters (upwelling zone and cyclonic eddy) compared with offshore waters (warm gyre). Zooplankton showed a great capacity for accumulations of trace metals, with average concentration factors of 4 867 929 ± 569 971, 246 757 ± 51 321, 337 180 ± 125 725, 43 480 ± 11 212, 1 046 371 ± 110 286, 601 679 ± 213 949, and 15 420 ± 9201 for Fe, Co, Ni, Cu, Zn, Cd, and Pb with respect to dissolved concentrations in coastal and offshore waters of the Bay of Bengal. © 2009 Wiley Periodicals, Inc. Environ Toxicol, 2009. Copyright © 2009 Wiley Periodicals, Inc.

  12. Self-bending of optical waveguides in a dry photosensitive medium

    NASA Astrophysics Data System (ADS)

    Malallah, Ra'ed; Wan, Min; Muniraj, Inbarasan; Cassidy, Derek; Sheridan, John T.

    2018-03-01

    Optical waveguide trajectories formed in an AA/PVA a photopolymer material photosensitive at 532 nm are examined. The transmission of light by this materials is discussed. The bending and arching of the waveguides which occur are investigated. The prediction of our model are shown to agree with the observed of trajectories. The largest index changes taking place at any time during the exposure, i.e. during SWW formation are found at the positions where the largest light intensity is present. Typically, such as maxima exist close to the input face at the location of the Primary Eye or at the location of the Secondary Eyes deeper with in the material. All photosensitive materials have a maximum saturation value of refractive index change that it is possible to induce, which is also discussed.

  13. Photosensitized generation of singlet oxygen by rhenium(I) complex

    NASA Astrophysics Data System (ADS)

    Burchinov, A. N.; Kiselev, V. M.; Penni, A. A.; Khistyaeva, V. V.

    2015-12-01

    The photosensitized generation of singlet oxygen in solutions of rhenium(I) complex fac-[Re(bipy)(CO)3NCCH3]+OTf-, where bipy=2,2'-bipyridine, in chloride methylene and carbon tetrachloride under continuous LED irradiation in the UV and visible ranges has been investigated.

  14. Contributions to the study of the mechanisms of photodynamic cross-linking of proteins

    NASA Astrophysics Data System (ADS)

    Shen, Hui-Rong

    The illumination of proteins in solution and in cells in the presence of photosensitizers may lead to the inter- and/or intramolecular crosslinking of the proteins (photosensitized or photodynamic crosslinking). This phenomenon appears to be involved in the photohemolysis of red cells, cataract development, skin photoaging, photodynamic therapy for cancers, laser welding of tissues, biomaterial modification, and other biological situations. Although the processes involved in the photocrosslinking of proteins have been extensively studied, the mechanisms involved are still largely unknown. The main objectives of the studies reported in this dissertation were to investigate the detailed mechanisms involved in the photocrosslinking of proteins and to determine the chemical nature of the crosslinks formed. The first part of this study was devoted to the verification of the roles of His, Lys and Tyr in the photodynamic crosslinking of proteins. The crosslinking reaction was modeled using tailor-made water-soluble synthetic N-(2-hydroxypropyl)methacrylamide (HPMA) copolymers containing epsilon-aminocaproic acid side chains terminating in His, Lys or tyrosinamide residues photosensitized by rose bengal (RB) and flavin mononucleotide (FMN). RB typically produces singlet oxygen, whereas FMN produces both singlet oxygen and radicals. His-His and His-Lys crosslinks were formed with RB as the sensitizer. RB-sensitization did not crosslink Tyr residues, whereas FMN coupled two Tyr residues via a radical pathway. Protection of the His and/or Lys residues in ribonuclease A (RNase A) significantly inhibited the extent of intermolecular crosslinking, and confirmed the key roles played by His and Lys in crosslinking reactions. The second part of this study involved the elucidation of the detailed reaction mechanisms and the chemical structures of His-His and Tyr-Tyr crosslinks. N-benzoyl-histidine (Bz-His) and N-acetyl-tyrosine (Ac-Tyr) were used to model the photosensitized

  15. Reconstructing Sea Surface Conditions in the Bay of Bengal during the Mid-Pleistocene Transition

    NASA Astrophysics Data System (ADS)

    Lagos, A. D.; Dekens, P.; Reilly, B. T.; Selkin, P. A.; Meynadier, L.; Savian, J. F.

    2017-12-01

    During the Mid-Pleistocene Transition (MPT, 0.8-1.2Ma) Earth's glacial cycles transitioned from responding primarily to 41kyr obliquity cycles to responding to 100kyr eccentricity cycles. In the tropics, sea surface temperature (SST) in the eastern tropical Pacific cooled through the MPT, suggesting a strengthening of the equatorial Pacific zonal temperature gradient (Medina-Elizalde & Lea, 2005). The strong SST gradient would have intensified Walker Cell convection during the MPT and built up latent heat in the western Pacific, which could cause cold SST anomalies in the northern Indian Ocean (Liu et al., 2015). Due to a scarcity of records, it is unclear how climate and oceanic conditions evolved in the Indian Ocean during the MPT. A set of recent IODP expeditions, including 353 and 354, cored sediment from the Bay of Bengal. Several sites recovered by expedition 353 will be ideal for reconstructing monsoon intensity through time, while the expedition 354 cores from a longitudinal transect at 8°N are in a region not directly impacted by changes in freshwater input due to direct precipitation or run off. The sites are influenced by the northeastern migration of equatorial Indian Ocean water via the Southwest Monsoon Current, which supplies significant moisture to the monsoon. Expedition 354's southern Bay of Bengal sites are well situated for better understanding the link between the tropical Indian Ocean and the northern Bay of Bengal. We reconstructed sea surface conditions at IODP site 1452 (8°N, 87°E, 3670m water depth) in the distal Bengal Fan. A 3 meter long section of the core has been identified as the MPT using the Bruhnes/Matuyama, Jaramillo, and Cobb Mountain paleomagnetic reversals (France-Lanord et al., 2016). This section of site 1452 was sampled every 2cm ( 2kyr resolution). Approximately 30 G. sacculifer, a surface dwelling planktonic foraminifera, were picked from the 355-425μm size fraction. We measured Mg/Ca and δ18O on splits of the same

  16. A Plume Head and Tail in the Bengal Basin and Bay of Bengal: Rajmahal and Sylhet Traps with Surrounding Alkalic Volcanism and the Ninetyeast Ridge

    NASA Astrophysics Data System (ADS)

    Basu, A. R.; Weaver, K. L.; Sengupta, S.

    2001-12-01

    Although the 116-113 Ma-old Rajmahal-Sylhet Traps of the Bengal basin, potentially covering an area > 2x105 km2, can be directly linked via Ninetyeast Ridge to the Kerguelen Plume, more than 5,000 kms away, it is generally believed that this flood basalt volcanism originated from a normal MORB-type mantle at the boundary of a mantle plume. This model, primarily based on geochemical analysis of a limited number of Rajmahal basalts, requires initiation of rifting of the eastern Indian margin by a smaller thermal flux than necessary for creating a large igneous province. Here we show that the extent of volcanism associated with the Rajmahal-Sylhet Traps is far greater than usually assumed, thus requiring a direct involvement of the Kerguelen Plume. In addition to the surface exposures of the flood basalts in Rajmahal-Sylhet, the basaltic rocks have been encountered in many parts of the Bengal Basin in bore holes reaching a maximum thickness of 600 m in the western margin of the Basin (Sengupta, Bull. AAPG, 1966) Most importantly, several suites of ultrapotassic and alkalic intrusive complexes, similar to those associated with the Deccan and Siberia Traps, occur over wide areas within and outside the Basin: i) southwest of the surface exposures of Rajmahal basalts, distance 200km, intrusive in Lower Gondwana coalbeds, Ar-Ar age 114 Ma (P.R. Renne, personal communication), ii) 400 km north of Rajmahal, exposed in Sikkim, intrusive into metamorphic crystalline nappes of the Himalayas; distance here is not real and must be a minimum as the nappes have been transported from the north, iii) northeast of Rajmahal in Meghalaya State, distance 550 km, intrusive into metamorphic Precambrian basement rocks. Nd-Sr isotopic ratios and trace element characteristics of these above ultrapotassic and alkaline rocks are consistent with their origin associated with the Kerguelen Plume. The wide range in Nd-Sr array for these rocks, including the Sylhet and Rajmahal basalts, shows

  17. Studies of vascular acting photosensitizer Tookad for the photodynamic therapy of prostate cancer

    NASA Astrophysics Data System (ADS)

    Huang, Zheng; Chen, Qun; Blanc, Dominique; Hetzel, Fred W.

    2005-01-01

    In this pre-clinical study, photodynamic therapy (PDT) mediated with a vascular acting photosensitizer Tookad (palladium-bacteriopheophorbide) is investigated as an alternative treatment modality for the ablation of prostate cancer. Canine prostate was used as the animal model. PDT was performed by interstitially irradiating the surgically exposed prostates with a diode laser (763 nm) to activate the IV infused photosensitizer. The effects of drug dose, drug-light interval, and light fluence rate on PDT efficacy were evaluated. The prostates and adjacent tissues were harvested at one-week post PDT and subjected to histopathological examination. The dogs recovered well with little or no urethral complications. Urinalysis showed trace blood. Histological examination showed minimal damage to the prostatic urethra. These indicated that the urethra was well preserved. PDT induced prostate lesions were characterized by marked hemorrhagic necrosis with a clear demarcation. Maximum lesion volume of ~3 cm3 could be achieved with a single 1-cm diffuser fiber at a dose level of 1 mg/kg and 200 J/cm, suggesting the therapy is very effective in ablating prostatic tissue. PDT induced lesion could reach the capsule layers but adjacent tissues were well preserved. The novel photosensitizer is a vascular drug and cleared rapidly from the circulation. Light irradiation can be performed during drug infusion thereby eliminating waiting time. The novel vascular acting photosensitizer Tookad-mediated PDT could provide an effective alternative to treat prostate cancer.

  18. Phthalocyanines as photosensitizing agents for tumors--mechanism of action

    NASA Astrophysics Data System (ADS)

    Ben-Hur, Ehud

    1994-03-01

    Aluminum phthalocyanine (AlPc) is a second-generation photosensitizer under study for photodynamic therapy (PDT) of cancer. Its mechanism of action is not known. Fluoride appears to be a powerful probe for the mechanistic study of AlPc derivatives. F- forms a complex with the Al ligand, resulting in drastically reduced AlPc-induced phototoxicity. This is due to a modified binding of AlPc with certain target proteins, resulting in inhibition of electron transfer reactions (type I) but not singlet oxygen reactions (type II). In Chinese hamster ovary (CHO) cell membranes, Na+/K+-ATPase activity is selectively protected by F- from photosensitized inhibition by AlPc, suggesting that this enzyme may be a critical target for AlPc-PDT. Another cellular response, not interfered with by F-, is a transient increase of cytoplasmic free Ca2+ after AlPc-PDT. This increase was shown to trigger the induction of a recovery process.

  19. Beta-lactamase targeted enzyme activatable photosensitizers for antimicrobial PDT

    NASA Astrophysics Data System (ADS)

    Zheng, Xiang; Verma, Sarika; Sallum, Ulysses W.; Hasan, Tayyaba

    2009-06-01

    Photodynamic therapy (PDT) as a treatment modality for infectious disease has shown promise. However, most of the antimicrobial photosensitizers (PS) non-preferentially accumulate in both bacteria and host tissues, causing host tissue phototoxicity during treatment. We have developed a new antimicrobial PDT strategy which exploits beta-lactam resistance mechanism, one of the major drug-resistance bacteria evolved, to achieve enhanced target specificity with limited host damage. Our strategy comprises a prodrug construct with a PS and a quencher linked by beta-lactam ring, resulting in a diminished phototoxicity. This construct, beta-lactamase enzyme-activated-photosensitizer (beta-LEAP), can only be activated in the presence of both light and bacteria, and remains inactive elsewhere such as mammalian tissue. Beta-LEAP construct had shown specific cleavage by purified beta-lactamase and by beta-lactamase over-expressing methicillin resistant Staphylococcus aureus (MRSA). Specific photodynamic toxicity was observed towards MRSA, while dark and light toxicity were equivalent to reference strains. The prodrug design, synthesis and photophysical properties will be discussed.

  20. Emergence of West Nile virus in West Bengal, India: a new report.

    PubMed

    Khatun, Tanuja; Chatterjee, Shyamalendu

    2017-04-01

    The ICMR virus unit in Kolkata functions as an Appex Referral Laboratory for the detection of dengue (DENV) and chikungunya (CHIKV) infections in the eastern part of India. In spite of efforts for confirmatory diagnosis, some samples remain undiagnosed every year. West Nile virus (WNV) infection may mimic either dengue (flavivirus) or chikungunya (alphavirus) like illness. WNV is endemic in the tropical region where its principal/potential vectors are Aedes and Culex. We explored the existence of WNV within undiagnosed samples to identify the emergence of a new public health problem. Of 1278 sera samples, 574 were negative for DENV and CHIKV either by ELISA or by reverse transcriptase (RT)-PCR. Of these 574 negative samples, 83 (14.5%) and 141 (24.56%) were positive for WNV by ELISA and RT-PCR, respectively; no samples were positive for WNV by both methods. After assembling raw sequencing data, partial envelope genome sequence of West Bengal isolates, WNV was compared through BLAST with other WNV Indian strains and 98% homology detected. Phylogenetic analysis of one West Bengal isolates (Accession No. KY421790) and 28 Indian isolates available in GenBank, indicated close clustering. The serological and molecular approaches have clearly established the emergence of WNV in West Bengal. Hence, for proper case management, detection of WNV in common febrile illness is strongly recommended. © The Author 2017. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  1. In vivo magnetic resonance measures of dark cytotoxicity of photosensitizers in a Murine tumor model

    NASA Astrophysics Data System (ADS)

    Ramaprasad, Subbaraya; Ripp, Elzbieta; Pi, Jiaxiong; Joshi, Shantaram S.; Pandey, Suresh K.; Missert, Joseph; Pandey, Ravindra K.

    2005-04-01

    Photodynamic therapy (PDT) is a novel cancer treatment modality where the therapeutic action is controlled by light and the potency of the photosensitizer used. Development of new potent photosensitizers (PS) for clinical applications requires that the PDT effects are maximized while minimizing dark cytotoxicity. The dark toxicity of photosensitizers is generally confirmed using cell lines. Photososensitizers that appear promising from in vitro assays need further investigations under in vivo conditions. As in vivo MR methods have the potential to provide information on the tumor status, they can be very effective tools to study dark toxicity of tumors. The tumor produced on the mouse foot dorsum was tested on two newly synthesized photosensitizers along with Photofrin as a control. The MR studies consisted of serial 31P spectral measurements both before and after PS injection. The results show significant changes in the tumor metabolism with increased inorganic phosphate while using new photosensitizers. However these changes slowly approached control levels several hours later. The studies performed while using Photofrin did not show any significant changes indicating minimal or no dark cytotoxicity. Similar studies performed on normal tissue such as the muscle indicated that the energy metabolism was minimally compromised. Our studies demonstrate that the effects of dark cytotoxicity can be observed by 31P MR. The growth profiles of tumors treated with PS alone indicate that the metabolic changes are temporary and do not interfere with the tumor growth. The studies suggest that MR is a new method of monitoring the effect of PS administered toxicity in an in vivo model.

  2. Identification of two new races of Diplocarpon rosae Wolf, the causal agent of rose black spot disease

    USDA-ARS?s Scientific Manuscript database

    The fungal pathogen, Diplocarpon rosae Wolf, infects only roses (Rosa spp.) and leads to rose black spot disease. Rose black spot is the most problematic disease of outdoor grown roses worldwide, due to the potential for rapid leaf yellowing and defoliation. Plants repeatedly defoliated from black ...

  3. Drug-induced acne and rose pearl: similarities*

    PubMed Central

    Pontello Junior, Rubens; Kondo, Rogerio Nabor

    2013-01-01

    Drug-induced acne is a common skin condition whose classic symptoms can be similar to a rose pearl, as in the case of a male patient presenting with this condition after excessive use of a cream containing corticosteroids. PMID:24474128

  4. Drilling history and stratigraphic correlation of Rose Run sandstone of northeastern Ohio

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moyer, C.C.

    1988-08-01

    To date, 40 known tests have penetrated the Knox unconformity in Ashtabula, Lake, Trumbull, Geauga, and Portage Counties, Ohio. Prior to 1980, there were only 22 tests. Of these, only 10 penetrated and logged rocks older than the Rose Run sandstone. In the period 1980-1986, two Rose Run discoveries were drilled, one in New Lyme Township of Ashtabula County and one in Burton Township of Geauga County. Both discovery wells have been offset. Attempts have been made to correlate these two areas with older tests in northeastern Ohio and with the Rose Run sandstones of Coshocton County. In northeastern Ohio,more » preliminary studies indicate a Rose Run sandstone and/or dolomite interval approximately 100 ft thick. The upper 50 ft is predominantly sandstone and the lower 50 ft changes locally from sandstone to dolomite. The upper sandy member can be correlated to the A, B, and C sandstone units of Coshocton County.« less

  5. Single Cell Responses to Spatially-Controlled Photosensitized Production of Extracellular Singlet Oxygen

    PubMed Central

    Pedersen, Brian Wett; Sinks, Louise E.; Breitenbach, Thomas; Schack, Nickolass B.; Vinogradov, Sergei A.; Ogilby, Peter R.

    2011-01-01

    The response of individual HeLa cells to extracellularly produced singlet oxygen was examined. The spatial domain of singlet oxygen production was controlled using the combination of a membrane-impermeable Pd porphyrin-dendrimer, which served as a photosensitizer, and a focused laser, which served to localize the sensitized production of singlet oxygen. Cells in close proximity to the domain of singlet oxygen production showed morphological changes commonly associated with necrotic cell death. The elapsed post-irradiation “waiting period” before necrosis became apparent depended on (a) the distance between the cell membrane and the domain irradiated, (b) the incident laser fluence and, as such, the initial concentration of singlet oxygen produced, and (c) the lifetime of singlet oxygen. The data imply that singlet oxygen plays a key role in this process of light-induced cell death. The approach of using extracellularly-generated singlet oxygen to induce cell death can provide a solution to a problem that often limits mechanistic studies of intracellularly photosensitized cell death: it can be difficult to quantify the effective light dose, and hence singlet oxygen concentration, when using an intracellular photosensitizer. PMID:21668871

  6. X ray photoelectron spectroscopy (XPS) analysis of Photosensitive ZrO2 array

    NASA Astrophysics Data System (ADS)

    Li, Y.; Zhao, G.; Zhu, R.; Kou, Z.

    2018-03-01

    Based on organic zirconium source as the starting material, by adding chemical modifiers which are made up with photosensitive ZrO2 sol. A uniformed ZrO2 array dot was fabricated with a mean diameter of around 800 nm. By using UV-vis spectra and X-ray photoelectron spectroscopy analysis method, studies the photosensitive ZrO2 gel film of photochemical reaction process and the photosensitive mechanism, to determine the zirconium atom centered chelate structure, reaction formed by metal chelate Zr atom for the center, and to establish the molecular model of the chelate. And studied the ultraviolet light in the process of the variation of the XPS spectra, Zr3d5/2 to 184.9 eV corresponding to the binding energy of the as the combination of state peak gradually reduce; By combining with the status of Zr-O peak gradually increase; The strength of the peak is gradually decline. This suggests that in the process of ultraviolet light photo chemical reaction happened. This study is of great significance to the micro fabrication of ZrO2 array not only to the memory devices but also to the optical devices.

  7. Influence of El Niño and Indian Ocean Dipole on sea level variability in the Bay of Bengal

    NASA Astrophysics Data System (ADS)

    Sreenivas, P.; Gnanaseelan, C.; Prasad, K. V. S. R.

    2012-01-01

    Zonally oscillating seasonal equatorial winds generate pairs of upwelling and downwelling Kelvin waves in the Equatorial Indian Ocean, which then advance in to the coastal Bay of Bengal. The first (second) equatorial upwelling Kelvin wave has its origin in the western (eastern) basin, whereas the downwelling Kelvin waves originate in the central basin. The observed interannual variability of these Kelvin waves is highly governed by the associated zonal wind changes in the central and eastern equatorial Indian Ocean during the anomalous years. The second downwelling (upwelling) Kelvin wave is absent (weak) during El Niño (La Niña) years, whereas the second upwelling Kelvin wave strengthened during El Niño years both in the equatorial Indian Ocean and Bay of Bengal. The large scale off equatorial Rossby waves occasionally feedback the equatorial Kelvin waves, which then strengthen the Bay of Bengal coastal Kelvin waves. The coastal Kelvin waves and the associated radiated Rossby waves from east play a dominant role in the mesoscale eddy generation in Bay of Bengal. The analysis of cyclogenesis characteristics in the bay over the past 65 years revealed that the active (suppressed) phases of cyclogenesis are coinciding with the downwelling (upwelling) planetary waves which influence the cyclone heat potential by altering the thermocline depth.

  8. Organic photosensitive devices using subphthalocyanine compounds

    DOEpatents

    Rand, Barry [Princeton, NJ; Forrest, Stephen R [Ann Arbor, MI; Mutolo, Kristin L [Hollywood, CA; Mayo, Elizabeth [Alhambra, CA; Thompson, Mark E [Anaheim Hills, CA

    2011-07-05

    An organic photosensitive optoelectronic device, having a donor-acceptor heterojunction of a donor-like material and an acceptor-like material and methods of making such devices is provided. At least one of the donor-like material and the acceptor-like material includes a subphthalocyanine, a subporphyrin, and/or a subporphyrazine compound; and/or the device optionally has at least one of a blocking layer or a charge transport layer, where the blocking layer and/or the charge transport layer includes a subphthalocyanine, a subporphyrin, and/or a subporphyrazine compound.

  9. A Photosensitizer-Loaded DNA Origami Nanosystem for Photodynamic Therapy.

    PubMed

    Zhuang, Xiaoxi; Ma, Xiaowei; Xue, Xiangdong; Jiang, Qiao; Song, Linlin; Dai, Luru; Zhang, Chunqiu; Jin, Shubin; Yang, Keni; Ding, Baoquan; Wang, Paul C; Liang, Xing-Jie

    2016-03-22

    Photodynamic therapy (PDT) offers an alternative for cancer treatment by using ultraviolet or visible light in the presence of a photosensitizer and molecular oxygen, which can produce highly reactive oxygen species that ultimately leading to the ablation of tumor cells by multifactorial mechanisms. However, this technique is limited by the penetration depth of incident light, the hypoxic environment of solid tumors, and the vulnerability of photobleaching reduces the efficiency of many imaging agents. In this work, we reported a cellular level dual-functional imaging and PDT nanosystem BMEPC-loaded DNA origami for photodynamic therapy with high efficiency and stable photoreactive property. The carbazole derivative BMEPC is a one- and two-photon imaging agent and photosensitizer with large two-photon absorption cross section, which can be fully excited by near-infrared light, and is also capable of destroying targets under anaerobic condition by generating reactive intermediates of Type I photodynamic reactions. However, the application of BMEPC was restricted by its poor solubility in aqueous environment and its aggregation caused quenching. We observed BMEPC-loaded DNA origami effectively reduced the photobleaching of BMEPC within cells. Upon binding to DNA origami, the intramolecular rotation of BMEPC became proper restricted, which intensify fluorescence emission and radicals production when being excited. After the BMEPC-loaded DNA origami are taken up by tumor cells, upon irradiation, BMEPC could generate free radicals and be released due to DNA photocleavage as well as the following partially degradation. Apoptosis was then induced by the generation of free radicals. This functional nanosystem provides an insight into the design of photosensitizer-loaded DNA origami for effective intracellular imaging and photodynamic therapy.

  10. Strong memory in time series of human magnetoencephalograms can identify photosensitive epilepsy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yulmetyev, R. M., E-mail: rmy@theory.kazan-spu.ru; Yulmetyeva, D. G.; Haenggi, P.

    2007-04-15

    To discuss the salient role of statistical memory effects in human brain functioning, we have analyzed a set of stochastic memory quantifiers that reflects the dynamical characteristics of neuromagnetic responses of magnetoencephalographic signals to a flickering stimulus of different color combinations from a group of control subjects, and compared them with those for a patient with photosensitive epilepsy. We have discovered that the emergence of strong memory and the accompanying transition to a regular and robust regime of chaotic behavior of signals in separate areas for a patient most likely identifies the regions where the protective mechanism against the occurrencemore » of photosensitive epilepsy is located.« less

  11. 33 CFR 165.1312 - Security Zone; Portland Rose Festival on Willamette River.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 33 Navigation and Navigable Waters 2 2011-07-01 2011-07-01 false Security Zone; Portland Rose Festival on Willamette River. 165.1312 Section 165.1312 Navigation and Navigable Waters COAST GUARD... § 165.1312 Security Zone; Portland Rose Festival on Willamette River. (a) Location. The following area...

  12. 33 CFR 165.1312 - Security Zone; Portland Rose Festival on Willamette River.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Security Zone; Portland Rose Festival on Willamette River. 165.1312 Section 165.1312 Navigation and Navigable Waters COAST GUARD... § 165.1312 Security Zone; Portland Rose Festival on Willamette River. (a) Location. The following area...

  13. Desert rose: building material of cupolas in the Souf in Algeria

    NASA Astrophysics Data System (ADS)

    Azil, C.; Djebri, B.; Rovero, L.

    2018-05-01

    In the Souf of Algeria, the roofs of all constructions are arranged like corbelled domes, built with local particular material to this region, which is the desert rose. These cupolas describe a unique landscape of historic centres. Such constructions include a widespread and precious heritage that deserves protection to save this urban landscape which constitutes an element of identity of heritage built upon the material as well as the immaterial of the local know-how. Unfortunately, these architectural elements have undergone alterations that devalue the urban landscape and destabilize the buildings. However, the structural system that provides stability and endurance to this day remains an open question. In this, paper, we describe the role of desert rose cupolas in the construction of a single urban landscape and we contribute to this knowledge. Then, we explain the role of the availability of the materials locals (desert rose and tafza) to appearance ad emergence of construction with cupolas typology. In addition, we describe these materials locals, and the method to them usage. In the end, we have traced the process of construction of these cupolas by corbelling which is mounted by successive courses of the desert rose and the plaster mortar.

  14. Rebamipide protects against glaucoma eyedrop-induced ocular surface disorders in rabbits

    PubMed Central

    Kawaguchi, Ichiro; Higashide, Tomomi; Takeji, Yasuhiro; Sakurai, Kazushi; Kawaguchi, Chiaki; Sugiyama, Kazuhisa

    2017-01-01

    Purpose This study aimed to determine if rebamipide eyedrops can improve ocular surface damage caused by the use of glaucoma eyedrops. Methods Female Kbl:Dutch rabbits were used to evaluate glaucoma eyedrop-induced ocular surface damage; one eye of each rabbit was untreated and the other was administered glaucoma eyedrops for 30 days. To evaluate the effects of rebamipide on ocular surface damage, one eye of each rabbit was administered vehicle-treated glaucoma eyedrops and the other was administered rebamipide-treated glaucoma eyedrops for 30 days. Corneal and conjunctival epithelial damage was evaluated using fluorescein and rose bengal staining, respectively. Conjunctival inflammation was observed by light microscopy with hematoxylin-eosin staining. Dark cells (in which the corneal microvilli were damaged) were analyzed by scanning electron microscopy. Results There were no significant differences in fluorescein staining between the untreated and glaucoma eyedrop-treated groups; however, rose bengal staining and the number of inflammatory cells in the conjunctiva significantly increased after glaucoma eyedrop treatment. There was a four-fold increase in the number of dark cells in the glaucoma eyedrop-treated group compared to untreated. In contrast, in the conjunctiva of the rebamipide-treated glaucoma eyedrop group, rose bengal staining scores, the number of inflammatory cells, and the number of dark cells were decreased compared to the vehicle-treated glaucoma eyedrop group. Conclusions Results from our in vivo rabbit study demonstrated that short-term use of glaucoma eyedrops induces corneal epithelium disorders at the cellular level, but that simultaneous use of rebamipide has the potential to protect and repair the ocular surface. PMID:29049370

  15. Rebamipide protects against glaucoma eyedrop-induced ocular surface disorders in rabbits.

    PubMed

    Kawaguchi, Ichiro; Kobayashi, Akira; Higashide, Tomomi; Takeji, Yasuhiro; Sakurai, Kazushi; Kawaguchi, Chiaki; Sugiyama, Kazuhisa

    2017-01-01

    This study aimed to determine if rebamipide eyedrops can improve ocular surface damage caused by the use of glaucoma eyedrops. Female Kbl:Dutch rabbits were used to evaluate glaucoma eyedrop-induced ocular surface damage; one eye of each rabbit was untreated and the other was administered glaucoma eyedrops for 30 days. To evaluate the effects of rebamipide on ocular surface damage, one eye of each rabbit was administered vehicle-treated glaucoma eyedrops and the other was administered rebamipide-treated glaucoma eyedrops for 30 days. Corneal and conjunctival epithelial damage was evaluated using fluorescein and rose bengal staining, respectively. Conjunctival inflammation was observed by light microscopy with hematoxylin-eosin staining. Dark cells (in which the corneal microvilli were damaged) were analyzed by scanning electron microscopy. There were no significant differences in fluorescein staining between the untreated and glaucoma eyedrop-treated groups; however, rose bengal staining and the number of inflammatory cells in the conjunctiva significantly increased after glaucoma eyedrop treatment. There was a four-fold increase in the number of dark cells in the glaucoma eyedrop-treated group compared to untreated. In contrast, in the conjunctiva of the rebamipide-treated glaucoma eyedrop group, rose bengal staining scores, the number of inflammatory cells, and the number of dark cells were decreased compared to the vehicle-treated glaucoma eyedrop group. Results from our in vivo rabbit study demonstrated that short-term use of glaucoma eyedrops induces corneal epithelium disorders at the cellular level, but that simultaneous use of rebamipide has the potential to protect and repair the ocular surface.

  16. Treatment of Sjögren's syndrome dry eye using 0.03% tacrolimus eye drop: Prospective double-blind randomized study.

    PubMed

    Moscovici, Bernardo Kaplan; Holzchuh, Ricardo; Sakassegawa-Naves, Fernando Eiji; Hoshino-Ruiz, Diego Ricardo; Albers, Marcos Bottene Villa; Santo, Ruth Miyuki; Hida, Richard Yudi

    2015-10-01

    To describe the clinical efficacy of the treatment of Sjögren's syndrome dry eye using 0.03% tacrolimus eye drop. Prospective double-blind randomized study. Institutional outpatient clinic. Forty-eight eyes of twenty-four patients with dry eye related to Sjögren syndrome were enrolled in this study. The patients were randomized in 2 groups: tacrolimus (n=14) and vehicle (n=10) group. The tacrolimus group received a vial containing tacrolimus 0.03% (almond oil as vehicle) and the other group received the almond oil vehicle. All patients were instructed to use the eye drops every 12h in the lower conjunctival sac. Schirmer I test, break-up-time (BUT), corneal fluorescein and Rose Bengal staining scores were evaluated in all patients one day before the treatment (baseline), 7, 14, 28 and 90 days after treatment with the eye drops. The average fluorescein and Rose Bengal scores improved statistically after 7 days of treatment and even more after 90 days. The average Schirmer I and BUT values were unchanged after 7, 14 and 21 days but did show an improvement relative to baseline after 28 days of treatment. Schirmer I, BUT, fluorescein and Rose Bengal did not show any statistical significance in the vehicle group. Topical 0.03% tacrolimus eye drop improved tear stability and ocular surface status in cases of inflammatory or SS-related dry eye. ClinicalTrials.gov Identifier: NCT01850979. Copyright © 2015 British Contact Lens Association. Published by Elsevier Ltd. All rights reserved.

  17. Origin of the color of Cv. rhapsody in blue rose and some other so-called "blue" roses.

    PubMed

    Gonnet, Jean-François

    2003-08-13

    Flowers of the rose cultivar Rhapsody in Blue display unusual colors, changing as they age, from a vivid red-purple to a lighter and duller purple, which are based on tonalities corresponding to hue angles between 340 and 320 degrees in the CIELAB scale. Unexpectedly, the chemical basis of these colors is among the simplest, featuring cyanin (cyanidin 3,5-di-O-glucoside), the most frequent anthocyanin in flowers, as the sole pigment and quercetin kaempferol glycosides as copigments at a relatively low copigment/pigment ratio (about 3/1), which usually produces magenta or red shades in roses. This color shift to bluer shades is coupled with the progressive accumulation of cyanin into vacuolar anthocyanic inclusions (AVIs), the occurrence of which increases as the petals grow older. In addition to the normal lambda(max) of cyanin at approximately 545 nm, the transmission spectra of live petals and of epidermal cells exhibit a second lambda(max) in the 620-625 nm range, the relative importance increasing with the presence of AVIs. In petals of fully opened flowers, the only pigmented structures in the vacuoles of epidermal cells are AVIs; their intense and massive absorption in the 520-640 nm area produces a much darker and bluer color than measured for the vacuolar solution present at the very first opening stage. Cyanin is probably "trapped" into AVIs at higher concentrations than would be possible in a vacuolar solution and in quinonoidal form, appearing purple-blue because of additional absorption in the 580-630 nm area. Quite similar pigmentation features were found in very ancient rose cultivars (cv. L'Evêque or Bleu Magenta), also displaying this type of so-called "blue" color.

  18. Triple-channel microreactor for biphasic gas-liquid reactions: Photosensitized oxygenations.

    PubMed

    Maurya, Ram Awatar; Park, Chan Pil; Kim, Dong-Pyo

    2011-01-01

    A triple-channel microreactor fabricated by means of a soft-lithography technique was devised for efficient biphasic gas-liquid reactions. The excellent performance of the microreactor was demonstrated by carrying out photosensitized oxygenations of α-terpinene, citronellol, and allyl alcohols.

  19. Ultrasonic activation and chemical modification of photosensitizers enhances the effects of photodynamic therapy against Enterococcus faecalis root-canal isolates.

    PubMed

    Tennert, C; Drews, A M; Walther, V; Altenburger, M J; Karygianni, L; Wrbas, K T; Hellwig, E; Al-Ahmad, A

    2015-06-01

    The aim of this study was to evaluate the effect of photodynamic therapy (PDT) on Enterococcus faecalis biofilms in artificially infected root canals using modified photosensitizers and passive ultrasonic activation. Two hundred and seventy extracted human teeth with one root canal were instrumented utilizing ProTaper files, autoclaved, infected with E. faecalis T9 for 72 h and divided into different groups: irrigation with 3% sodium hypochlorite (NaOCl), 20% ethylenediaminetetraacetic acid (EDTA), or 20% citric acid, PDT without irrigation, PDT accompanied by irrigation with NaOCl, EDTA, or citric acid, PDT using an EDTA-based photosensitizer or a citric-acid-based photosensitizer and PDT with ultrasonic activation of the photosensitizer. A 15 mg/ml toluidine blue served as the photosensitizer, activated by a 100 mW LED light source. Sterile paper points were used for sampling the root canals and dentin chips were collected to assess the remaining contamination after treatment. Samples were cultured on blood agar plates and colony forming units were quantified. PDT alone achieved a reduction in E. faecalis counts by 92.7%, NaOCl irrigation alone and combined with PDT by 99.9%. The antibacterial effects increased by the combination of irrigation using EDTA or citric acid and PDT compared to irrigation alone. More than 99% of E. faecalis were killed using PDT with the modified photosensitizers and ultrasonic activation. NaOCl based disinfection achieved the highest antimicrobial effect. Using PDT with an EDTA-based or citric-acid-based phozosensitizer or activating the photosensitizer with ultrasound resulted in a significantly higher reduction in E. faecalis counts compared to conventional PDT. Copyright © 2015 Elsevier B.V. All rights reserved.

  20. Tinkering with the C-Function: A Molecular Frame for the Selection of Double Flowers in Cultivated Roses

    PubMed Central

    Dubois, Annick; Raymond, Olivier; Maene, Marion; Baudino, Sylvie; Langlade, Nicolas B.; Boltz, Véronique; Vergne, Philippe; Bendahmane, Mohammed

    2010-01-01

    Background Roses have been cultivated for centuries and a number of varieties have been selected based on flower traits such as petal form, color, and number. Wild-type roses have five petals (simple flowers), whereas high numbers of petals (double flowers) are typical attributes of most of the cultivated roses. Here, we investigated the molecular mechanisms that could have been selected to control petal number in roses. Methodology/Principal Findings We have analyzed the expression of several candidate genes known to be involved in floral organ identity determination in roses from similar genetic backgrounds but exhibiting contrasting petal numbers per flower. We show that the rose ortholog of AGAMOUS (RhAG) is differentially expressed in double flowers as compared to simple flowers. In situ hybridization experiments confirm the differential expression of RhAG and demonstrate that in the double-flower roses, the expression domain of RhAG is restricted toward the center of the flower. Conversely, in simple-flower roses, RhAG expression domain is wider. We further show that the border of RhAG expression domain is labile, which allows the selection of rose flowers with increased petal number. Double-flower roses were selected independently in the two major regions for domestication, China and the peri-Mediterranean areas. Comparison of RhAG expression in the wild-type ancestors of cultivated roses and their descendants both in the European and Chinese lineages corroborates the correlation between the degree of restriction of RhAG expression domain and the number of petals. Our data suggests that a restriction of RhAG expression domain is the basis for selection of double flowers in both the Chinese and peri-Mediterranean centers of domestication. Conclusions/Significance We demonstrate that a shift in RhAG expression domain boundary occurred in rose hybrids, causing double-flower phenotype. This molecular event was selected independently during rose domestication in

  1. Seasonal induction of alternative principal pathway for rose flower scent

    PubMed Central

    Hirata, Hiroshi; Ohnishi, Toshiyuki; Tomida, Kensuke; Ishida, Haruka; Kanda, Momoyo; Sakai, Miwa; Yoshimura, Jin; Suzuki, Hideyuki; Ishikawa, Takamasa; Dohra, Hideo; Watanabe, Naoharu

    2016-01-01

    Ecological adaptations to seasonal changes are often observed in the phenotypic traits of plants and animals, and these adaptations are usually expressed through the production of different biochemical end products. In this study, ecological adaptations are observed in a biochemical pathway without alteration of the end products. We present an alternative principal pathway to the characteristic floral scent compound 2-phenylethanol (2PE) in roses. The new pathway is seasonally induced in summer as a heat adaptation that uses rose phenylpyruvate decarboxylase (RyPPDC) as a novel enzyme. RyPPDC transcript levels and the resulting production of 2PE are increased time-dependently under high temperatures. The novel summer pathway produces levels of 2PE that are several orders of magnitude higher than those produced by the previously known pathway. Our results indicate that the alternative principal pathway identified here is a seasonal adaptation for managing the weakened volatility of summer roses. PMID:26831950

  2. Precise Two-Photon Photodynamic Therapy using an Efficient Photosensitizer with Aggregation-Induced Emission Characteristics.

    PubMed

    Gu, Bobo; Wu, Wenbo; Xu, Gaixia; Feng, Guangxue; Yin, Feng; Chong, Peter Han Joo; Qu, Junle; Yong, Ken-Tye; Liu, Bin

    2017-07-01

    Two-photon photodynamic therapy (PDT) is able to offer precise 3D manipulation of treatment volumes, providing a target level that is unattainable with current therapeutic techniques. The advancement of this technique is greatly hampered by the availability of photosensitizers with large two-photon absorption (TPA) cross section, high reactive-oxygen-species (ROS) generation efficiency, and bright two-photon fluorescence. Here, an effective photosensitizer with aggregation-induced emission (AIE) characteristics is synthesized, characterized, and encapsulated into an amphiphilic block copolymer to form organic dots for two-photon PDT applications. The AIE dots possess large TPA cross section, high ROS generation efficiency, and excellent photostability and biocompatibility, which overcomes the limitations of many conventional two-photon photosensitizers. Outstanding therapeutic performance of the AIE dots in two-photon PDT is demonstrated using in vitro cancer cell ablation and in vivo brain-blood-vessel closure as examples. This shows therapy precision up to 5 µm under two-photon excitation. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Photo-oxidation of ergosterol: indirect detection of antioxidants photosensitizers or quenchers of singlet oxygen.

    PubMed

    Lagunes, Irene; Trigos, Ángel

    2015-04-01

    Consumption of antioxidant supplements is associated to prevention of several diseases. However, recent studies suggest that antioxidants, besides scavenge free radicals could lead development of tumors. Due to conflicting reports on the antioxidant benefits, the capacity to photosensitize the generation of singlet oxygen of seven natural antioxidants was evaluated through photo-oxidation of ergosterol which proved to be an efficient method of indirect detection of singlet oxygen. Our results showed that curcumin, resveratrol and quercetin have pro-oxidant activity due they act as photosensitizers in generation of singlet oxygen. In addition, we observed that genistein, naringenin, β-carotene and gallic acid besides their antioxidant activity against ROS radicals, are capable of quenching ROS non-radicals as singlet oxygen. Finally, our results allow us to propose a new approach in classification of natural antioxidants scavengers of free radicals, based on their activity as quenchers of singlet oxygen or as photosensitizers in singlet oxygen generation. Copyright © 2015. Published by Elsevier B.V.

  4. The Sex Education Debates: Teaching "Life Style" in West Bengal, India

    ERIC Educational Resources Information Center

    Chakravarti, Paromita

    2011-01-01

    This paper examines the recent controversies surrounding the decision to introduce sex education in secondary schools in India to combat the rapid spread of HIV and AIDS in the country. While 11 Indian states have banned it, the Left-ruled state of West Bengal has designed a teachers' manual to impart sex education. However, a close analysis of…

  5. Synthesis of rose-like boron nitride particles with a high specific surface area

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yu, Hongming; Huang, Xiaoxiao; Wen, Guangwu, E-mail: wgw@hitwh.edu.cn

    2010-08-15

    Novel rose-like BN nanostructures were synthesized on a large scale via a two-step procedure. The products were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Fourier transform infrared spectroscopy, X-ray photoelectron spectrometer and nitrogen porosimetry. The results show that the obtained rose-like nanostructures are composed of a large amount of h-BN crystalline flakes and have a surface area of 90.31 m{sup 2}/g. A mechanism was proposed to explain the formation process of the rose-like BN nanostructures.

  6. 78 FR 33047 - Humboldt-Toiyabe National Forest, Carson Ranger District Mt. Rose Ski Tahoe-Atoma Area...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-03

    ... the effects of a proposal from Mt. Rose Ski Tahoe (Mt. Rose) to expand its lift and terrain network... to create the Atoma lift and trail ``Pod'' to the north of the Mt. Rose Highway. The proposed Atoma... facilitate construction and [[Page 33048

  7. Betacyanins pigments as photosensitizing agents for holographic recording medium

    NASA Astrophysics Data System (ADS)

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

    2014-02-01

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

  8. Triple-channel microreactor for biphasic gas–liquid reactions: Photosensitized oxygenations

    PubMed Central

    Maurya, Ram Awatar; Park, Chan Pil

    2011-01-01

    Summary A triple-channel microreactor fabricated by means of a soft-lithography technique was devised for efficient biphasic gas–liquid reactions. The excellent performance of the microreactor was demonstrated by carrying out photosensitized oxygenations of α-terpinene, citronellol, and allyl alcohols. PMID:21915221

  9. Isolation of an arsenate-respiring bacterium from a redox front in an arsenic-polluted aquifer in West Bengal, Bengal Basin.

    PubMed

    Osborne, Thomas H; McArthur, John M; Sikdar, Pradip K; Santini, Joanne M

    2015-04-07

    Natural pollution of groundwater by arsenic adversely affects the health of tens of millions of people worldwide, with the deltaic aquifers of SE Asia being particularly polluted. The pollution is caused primarily by, or as a side reaction of, the microbial reduction of sedimentary Fe(III)-oxyhydroxides, but the organism(s) responsible for As release have not been isolated. Here we report the first isolation of a dissimilatory arsenate reducer from sediments of the Bengal Basin in West Bengal. The bacterium, here designated WB3, respires soluble arsenate and couples its reduction to the oxidation of acetate; WB3 is therefore implicated in the process of arsenic pollution of groundwater, which is largely by arsenite. The bacterium WB3 is also capable of reducing dissolved Fe(III) citrate, solid Fe(III)-oxyhydroxide, and elemental sulfur, using acetate as the electron donor. It is a member of the Desulfuromonas genus and possesses a dissimilatory arsenate reductase that was identified using degenerate polymerase chain reaction primers. The sediment from which WB3 was isolated was brown, Pleistocene sand at a depth of 35.2 m below ground level (mbgl). This level was some 3 cm below the boundary between the brown sands and overlying reduced, gray, Holocene aquifer sands. The color boundary is interpreted to be a reduction front that releases As for resorption downflow, yielding a high load of labile As sorbed to the sediment at a depth of 35.8 mbgl and concentrations of As in groundwater that reach >1000 μg/L.

  10. Ultraviolet photosensitivity of sulfur-doped micro- and nano-crystalline diamond

    DOE PAGES

    Mendoza, Frank; Makarov, Vladimir; Hidalgo, Arturo; ...

    2011-06-06

    The room-temperature photosensitivity of sulfur-doped micro- (MCD), submicro- (SMCD) and nano- (NCD) crystalline diamond films synthesized by hot-filament chemical vapor deposition was studied. The structure and composition of these diamond materials were characterized by Raman spectroscopy, scanning electron microscopy and X-ray diffraction. The UV sensitivity and response time were studied for the three types of diamond materials using a steady state broad UV excitation source and two pulsed UV laser radiations. It was found that they have high sensitivity in the UV region, as high as 10 9 sec -1mV -1 range, linear response in a broad spectral range belowmore » 320 nm, photocurrents around ~10 -5 A, and short response time better than 100 ns, which is independent of fluency intensity. A phenomenological model was applied to help understand the role of defects and dopant concentration on the materials’ photosensitivity.« less

  11. Studies of a novel photosensitizer Pd-bacteriopheophorbide (Tookad) for the prostate cancer PDT in canine model

    NASA Astrophysics Data System (ADS)

    Huang, Zheng; Chen, Qun; Brun, Pierre-Herve; Wilson, Brian C.; Scherz, Avigdor; Salomon, Yoram; Luck, David L.; Beckers, Jill; Hetzel, Fred W.

    2003-12-01

    Photodynamic therapy (PDT) mediated with vascular acting photosensitizer pd-bacteriopheophorbide (Tookad), is investigated as an alternative modality for the total ablation of prostate cancer. In vivo normal canine prostate is used as the animal model. Interstitial PDT was performed by irradiating the surgically exposed prostates with a diode laser (763 nm, 150 mW/cm) to activate the i.v. infused photosensitizer drug. The effects of two-session PDT were evaluated. The prostate and its adjacent tissues were harvested and subjected to histopathological examination. At one-week, post second-session PDT, the animals recovered well with little or no urethral complications. Prostatic urethra and prostate adjacent tissues (bladder and underlying colon) were well preserved. Two-session PDT or one single session PDT induced a similar extent of damage. PDT induced prostate lesions were characterized by marked hemorrhagic necrosis. Maximum lesion size of over 3 cm in dimension could be achieved with a single 1-cm interstitial treatment, suggesting the therapy is very effective in ablating prostatic tissue. Pharmacokinetic studies show that the photosensitizer is cleared rapidly from the circulation. In conclusion, the novel photosensitizer Tookad mediated PDT may provide an effective alternative to treat prostate cancer.

  12. Photoluminescence of cerium fluoride and cerium-doped lanthanum fluoride nanoparticles and investigation of energy transfer to photosensitizer molecules.

    PubMed

    Cooper, Daniel R; Kudinov, Konstantin; Tyagi, Pooja; Hill, Colin K; Bradforth, Stephen E; Nadeau, Jay L

    2014-06-28

    CexLa1-xF3 nanoparticles have been proposed for use in nanoscintillator-photosensitizer systems, where excitation of nanoparticles by ionizing radiation would result in energy transfer to photosensitizer molecules, effectively combining the effects of radiotherapy and photodynamic therapy. Thus far, there have been few experimental investigations of such systems. This study reports novel synthesis methods for water-dispersible Ce0.1La0.9F3/LaF3 and CeF3/LaF3 core/shell nanoparticles and an investigation of energy transfer to photosensitizers. Unbound deuteroporphyrin IX 2,4-disulfonic acid was found to substantially quench the luminescence of large (>10 nm diameter) aminocaproic acid-stabilized nanoparticles at reasonable concentrations and loading amounts: up to 80% quenching at 6% w/w photosensitizer loading. Energy transfer was found to occur primarily through a cascade, with excitation of "regular" site Ce(3+) at 252 nm relayed to photosensitizer molecules at the nanoparticle surface through intermediate "perturbed" Ce(3+) sites. Smaller (<5 nm) citrate-stabilized nanoparticles were coated with the bisphosphonate alendronate, allowing covalent conjugation to chlorin e6 and resulting in static quenching of the nanoparticle luminescence: ∼50% at ∼0.44% w/w. These results provide insight into energy transfer mechanisms that may prove valuable for optimizing similar systems.

  13. Characterization of clinical photosensitivity in cutaneous lupus erythematosus.

    PubMed

    Foering, Kristen; Chang, Aileen Y; Piette, Evan W; Cucchiara, Andrew; Okawa, Joyce; Werth, Victoria P

    2013-08-01

    Photosensitivity (PS) in lupus erythematosus (LE) is frequently determined by patient report. We sought to characterize self-reported PS in cutaneous LE (CLE). The PS survey was used to classify subject responses into 5 phenotypes: direct sun-induced CLE flare (directCLE); general exacerbation of CLE (genCLE); polymorphic light eruption-like reactions (genSkin); general pruritus/paresthesias (genRxn); and sun-induced systemic symptoms (genSys). In all, 91 subjects with CLE alone or with CLE and systemic LE were interviewed. In all, 81% ascribed to 1 or more PS phenotypes. CLE-specific reactions (direct sun-induced CLE flare or general exacerbation of CLE) were reported by 86% of photosensitive subjects. Higher CLE disease activity (measured by CLE Disease Area and Severity Index activity scores) was suggestive of direct sun-induced CLE flare reactions (P = .09). In all, 60% of photosensitive subjects described CLE-nonspecific reactions: polymorphic light eruption-like rash and general pruritus/paresthesias. These phenotypes often co-occurred with CLE-specific reactions and were predicted by more systemic disease activity as measured by Physicians Global Assessment (PGA) scores in regression analyses (genSkin, P = .02) and (genRxn, P = .05). In all, 36% of subjects reported systemic reactions and higher PGA scores were predictive of the sun-induced systemic symptoms phenotype (P = .02); a diagnosis of systemic LE was not (P = .14). PS was inferred from patient report and not directly observed. Characterization of self-reported PS in LE reveals that patients experience combinations of CLE-specific, CLE-nonspecific, and systemic reactions to sunlight. Sun-induced CLE flares are associated with more active CLE disease. Polymorphic light eruption-like, generalized pruritus/paresthesias, and systemic reactions are associated with more active systemic disease. Recognition of PS phenotypes will permit improved definitions of clinical PS and allow for more precise

  14. Professional photosensitive eczema of fishermen by contact with bryozoans: disabling occupational dermatosis.

    PubMed

    Clin, Benedicte; Stosse-Guevel, Catherine; Marquignon, Marie-France; Verneuil, Laurence; Letourneux, Marc

    2008-01-01

    Eczema associated with bryozoans is a form of occupational dermatosis caused by a living animal, involving contact eczema, occasionally associated with photosensitivity and concerning fishermen on a quasi-elective basis. This affection can prove to be extremely disabling, frequently generating disastrous social consequences, since the eviction of the responsible allergen is very often synonymous to occupational reclassification, a measure which fishermen, highly attached to their profession, have great difficulty in accepting. Based on the description of three cases of photosensitive eczema associated with contact with the bryozoan, Alcyonidium gelatinosum, identified in fishermen from the English Channel coastline, we describe the characteristics and the specificities of this occupational dermatosis, then approach the issue of its prevention, which, unfortunately, remains limited.

  15. Incidental retinal phototoxicity associated with ingestion of photosensitizing drugs.

    PubMed

    Mauget-Faÿsse, M; Quaranta, M; Francoz, N; BenEzra, D; Mauget-Fa, M

    2001-07-01

    to report on the possible correlation between incident retinal phototoxicity and the use of photosensitizing drugs. four patients were examined because of scotomas and visual loss after an incidental exposure to a strong light source. One patient (two eyes) was exposed to standard camera flash; one patient (one eye) had a brief exposure to welding light; one patient (two eyes) underwent uncomplicated phacoemulsifications with intraocular lens implantation. The fourth patient had a severe retinal phototoxicity following a secondary intraocular lens implantation. All four patients underwent a thorough assessment including history of systemic drug use. These patients had ophthalmologic evaluation including: best corrected visual acuity (ETDRS charts), fundus examination, fluorescein and indocyanine green angiographies and were followed for 1 year. on presentation, the mean visual acuity was 7.5/20 (range: 20/400-20/20). Fundus examination disclosed yellow-gray sub-retinal lesions in all affected eyes. Early phase fluorescein angiography showed one or multiple hypofluorescent spots surrounded by a halo of hyperfluorescent window defect. In the late phase, some of these spots leaked the fluorescein dye. Indocyanine green angiography demonstrated hypofluorescent spots throughout with ill-defined borders of hyperfluorescence observed during the late stages. The common finding in these four patients was the fact that they were all taking one or more photosensitizing drugs (hydrochlorothiazide, furosemide, allopurinol, and benzodiazepines). Three of the patients had a full visual recovery a few months after the phototoxicity. The fourth patient remained with a visual acuity of 20/60 12 months after the light exposure. Despite the visual recovery, non-homogeneous retinal pigment epithelial disturbances persisted in all affected eyes. phototoxicity following incidental light exposure may occur in patients taking drugs of photosensitizing potential. Therefore, the thorough

  16. Organic photosensitive optoelectronic device having a phenanthroline exciton blocking layer

    DOEpatents

    Thompson, Mark E [Anaheim Hills, CA; Li, Jian [Los Angeles, CA; Forrest, Stephen [Princeton, NJ; Rand, Barry [Princeton, NJ

    2011-02-22

    An organic photosensitive optoelectronic device, having an anode, a cathode, and an organic blocking layer between the anode and the cathode is described, wherein the blocking layer comprises a phenanthroline derivative, and at least partially blocks at least one of excitons, electrons, and holes.

  17. Photodynamic chlorophyll a metabolites, including phytoporphyrin (phylloerythrin), in the blood of photosensitive livestock: overview and measurement.

    PubMed

    Campbell, W M; Dombroski, G S; Sharma, I; Partridge, A C; Collett, M G

    2010-06-01

    To validate a spectrofluorometric method for measuring chlorophyll a metabolites, specifically phytoporphyrin (= phylloerythrin), as well as the chlorins, pheophorbide a and pyropheophorbide a, in the blood of photosensitive cattle and sheep. Standard methanolic solutions of pheophorbide a (25 microM), pyropheophorbide a (25 microM), and phytoporphyrin (<3.7 microM) were prepared. Serum and plasma samples were obtained from cattle (n=5), sheep (n=3), and one alpaca, with clinical facial eczema (i.e. photosensitive), as well as from clinically normal (n=2 of each) adult cows, recently weaned calves, and sheep (controls). Standard solutions of the three metabolites were characterised using high-performance liquid chromatography (HPLC), with mass spectrometry, in conjunction with absorption and emission spectral data, and were compared with sera from photosensitive animals. In the latter, phytoporphyrin was the only metabolite detected. Calibration curves were prepared by adding different ratios of methanol and standard solutions of phytoporphyrin in methanol to diluted serum from control animals. Peak areas of fluorescence spectra were determined in samples from photosensitive animals. Pheophorbide a and pyropheophorbide a produced typical chlorin spectra, and had excitation/emission maxima of 408/669 nm and 409/669 nm, respectively. Phytoporphyrin showed a typical porphyrin fluorescence spectrum, with excitation/ emission maxima of 425/644 nm. Pyropheophorbide a and phytoporphyrin had very similar chromatographic retention times, the same chemical formula and same mass, but were distinguishable by differences in their absorption spectra. In sera from photosensitive animals, the fluorescence emission at 644 nm was shown to arise solely from phytoporphyrin and not from any other chlorophyll a metabolites. Calibration curves using sera and plasma from control animals gave reliable measurements of phytoporphyrin in the range 0.4-6 microM. The sera of facial eczema

  18. Rose Canyon Sustainable Aquaculture Project, San Diego, CA

    EPA Pesticide Factsheets

    Documents related to EPA's preparation of an Environmental Assessment (EA) to analyze the potential impacts related to the issuance of a National Pollutant Discharge Elimination System (NPDES) permit for the Rose Canyon Sustainable Aquaculture Project.

  19. On the dynamics of the Sri Lanka Dome in the Bay of Bengal

    NASA Astrophysics Data System (ADS)

    Burns, Jessica M.; Subrahmanyam, Bulusu; Murty, V. S. N.

    2017-09-01

    East of Sri Lanka, in the northern Indian Ocean, a cold dome, known as the Sri Lanka Dome (SLD), develops during southwest monsoon season (June-September). The SLD first forms around May, matures in July, and decays around September, in association with the strong cyclonic wind stress curl. In this study, the structure and dynamics of SLD in response to the climatic events such as the Indian Ocean Dipole (IOD) are examined. Our results reveal that these climatic events modulated the subsurface temperature variability in the thermocline at ˜100 m depth, whose signature was also evident in the satellite-derived sea surface height (SSH) anomaly in the SLD region. We find that the mechanisms for the formation of SLD are consistent with previous research, and there is year-to-year variability in the SLD dynamics. This study also reveals that the atmospheric parameters including vertical wind shear and midtropospheric relative humidity are high over the SLD region and adjacent southern Bay of Bengal and show an upward (increasing) trend over the decades. This has impacted the atmospheric parameters over the northern Bay of Bengal over the decades and as a consequence the total number of monsoon depressions (June-September) decreased over the decades from 1980 to 2015, as reported by the India Meteorological Department, New Delhi. Thus, the new insight emerged from this study is the variability in the cyclogenesis and the occurrence of total number of monsoon depressions over northern Bay of Bengal over the decades is much related to the SLD dynamics.

  20. Raman microspectroscopy of Hematoporphyrins. Imaging of the noncancerous and the cancerous human breast tissues with photosensitizers

    NASA Astrophysics Data System (ADS)

    Brozek-Pluska, B.; Kopec, M.

    2016-12-01

    Raman microspectroscopy combined with fluorescence were used to study the distribution of Hematoporphyrin (Hp) in noncancerous and cancerous breast tissues. The results demonstrate the ability of Raman spectroscopy to distinguish between noncancerous and cancerous human breast tissue and to identify differences in the distribution and photodegradation of Hematoporphyrin, which is a photosensitizer in photodynamic therapy (PDT), photodynamic diagnosis (PDD) and photoimmunotherapy (PIT) of cancer. Presented results show that Hematoporphyrin level in the noncancerous breast tissue is lower compared to the cancerous one. We have proved also that the Raman intensity of lipids and proteins doesn't change dramatically after laser light irradiation, which indicates that the PDT treatment destroys preferably cancer cells, in which the photosensitizer is accumulated. The specific subcellular localization of photosensitizer for breast tissues samples soaked with Hematoporphyrin was not observed.

  1. Mycobiota of Lupinus albus seed from a public germplasm collection

    USDA-ARS?s Scientific Manuscript database

    Seedborne mycobiota of Lupinus albus was assessed using blotter paper and agar media with Rose Bengal or semi-selective for Pythium or Fusarium. Samples of 200 seeds were taken from each of 16 inventories, comprising 14 accessions originating from Germany, France, Ukraine, Syria, Hungary or Spain, a...

  2. Workflow to study genetic biodiversity of aflatoxigenic Aspergillus spp. in Georgia, USA

    USDA-ARS?s Scientific Manuscript database

    Peanut seeds were sampled from the entire state of Georgia in 2014. More than 600 isolates of Aspergillus spp. were collected using modified-dichloran rose Bengal (MDRB) medium, 240 of those isolates were fingerprinted with 25 InDel markers within the aflatoxin-biosynthesis gene cluster (ABC). Clust...

  3. Mixing to Monsoons: Air-Sea Interactions in the Bay of Bengal

    NASA Astrophysics Data System (ADS)

    Lucas, A. J.; Shroyer, E. L.; Wijesekera, H. W.; Fernando, H. J. S.; D'Asaro, E.; Ravichandran, M.; Jinadasa, S. U. P.; MacKinnon, J. A.; Nash, J. D.; Sharma, R.; Centurioni, L.; Farrar, J. T.; Weller, R.; Pinkel, R.; Mahadevan, A.; Sengupta, D.; Tandon, A.

    2014-07-01

    More than 1 billion people depend on rainfall from the South Asian monsoon for their livelihoods. Summertime monsoonal precipitation is highly variable on intraseasonal time scales, with alternating "active" and "break" periods. These intraseasonal oscillations in large-scale atmospheric convection and winds are closely tied to 1°C-2°C variations of sea surface temperature in the Bay of Bengal.

  4. Recovery of polyphenols from rose oil distillation wastewater using adsorption resins--a pilot study.

    PubMed

    Rusanov, Krasimir; Garo, Eliane; Rusanova, Mila; Fertig, Orlando; Hamburger, Matthias; Atanassov, Ivan; Butterweck, Veronika

    2014-11-01

    The production of rose oil from rose flowers by water steam distillation leaves a water fraction of the distillate as main part of the waste. Therefore, the rose oil distillation wastewater represents a serious environmental problem due to the high content of polyphenols which are difficult to decompose and have to be considered as biopollutants when discarded into the drainage system and rivers. On the other hand, natural polyphenols are valuable compounds with useful properties as bioactive substances. Until now there is no established practice for processing of rose oil distillation wastewater and utilization of contained substances. Thus, it was the aim of this study to develop a strategy to separate this wastewater into a polyphenol depleted water fraction and a polyphenol enriched fraction which could be developed into innovative value-added products. In a first step, the phytochemical profile of rose oil distillation wastewater was determined. Its HPLC-PDA-MS analysis revealed the presence of flavan-3-ols, flavanones, flavonols and flavones. In a second step, the development of a stepwise concentration of rose oil distillation wastewater was performed. The concentration process includes a filtration process to eliminate suspended solids in the wastewater, followed by adsorption of the contained phenolic compounds onto adsorption resins (XAD and SP). Finally, desorption of the polyphenol fraction from the resin matrix was achieved using ethanol and/or aqueous ethanol. The result of the process was a wastewater low in soluble organic compounds and an enriched polyphenol fraction (RF20 SP-207). The profile of this fraction was similar to that of rose oil distillation wastewater and showed the presence of flavonols such as quercetin and kaempferol glycosides as major metabolites. These compounds were isolated from the enriched polyphenol fraction and their structures confirmed by NMR. In summary, a pilot medium scale system was developed using adsorption resins

  5. The nature and molecular basis of cutaneous photosensitivity reactions to psoralens and coal tar

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Pathak, M.A.; Joshi, P.C.

    1983-06-01

    The basic aspects of cutaneous photosensitization reactions and the mode of therapeutic effectiveness of psoralens and coal tar, the two groups of photosensitizing agents used extensively in the photochemotherapy of psoriasis, have been reviewed. Psoralen-induced skin photosensitization and the therapeutic action of psoralens involve two distinct types of reactions, and these two reactions occur independently of each other and concurrently when the psoralen-treated skin (oral or topical) is exposed to 320 to 400 nm of radiation. The first, type I, is an oxygen-independent reaction and primarily involves photoreaction with DNA; the second, type II, is a sensitized reaction dependent onmore » oxygen and involves the formation of singlet oxygen (1O2). The photoreactive form of psoralen is its triplet state, and the sites of reaction are (1) the cell membrane of the epidermal, dermal, and endothelial cells; (2) the cytoplasmic constituents, such as enzymes, RNA, lysosomes, etc.; (3) the cell nuclei (DNA and chromatin); and (4) the sensitized production of 1O2, which is responsible for cell-membrane damage and vasodilation. The major damage would be initiated by a type I reaction and would be seen in the form of nuclear damage to DNA resulting from the interaction of psoralen with DNA and to a lesser extent with RNA. The skin photosensitization response (erythema, edema, membrane damage, etc.) would result from a type II reaction involving the generation of 1O2. Crude coal tar (CCT), widely used in the Goeckerman therapy for psoriasis, also produces type I and type II reactions. The therapeutic and photosensitizing actions of CCT are due to (1) the photoconjugation of the photoreactive ingredients of CCT with DNA, causing interstrand cross-links; and (2) the production of 1O2. CCT is an efficient producer of 1O2, more so than 8-methoxypsoralen, and is responsible for cell-membrane damage and cellular edema.« less

  6. Preliminary clinical data on a new photodynamic therapy photosensitizer: 2-[1-hexyloxyethyl]-2-devinylpyropheophorbide-a (HPPH) for treatment of obstructive esophageal cancer

    NASA Astrophysics Data System (ADS)

    Dougherty, Thomas J.; Pandey, R. K.; Nava, Hector R.; Smith, Judy L.; Douglass, Harold O.; Edge, Stephen B.; Bellnier, David A.; O'Malley, Linda; Cooper, Michele

    2000-03-01

    The hexyl ether derivative or HPPH, has been identified as an optimal active in vivo photosensitizer in pre-clinical studies and has been evaluated clinically in obstructive esophageal cancer in five patients to date. The photosensitizer appears to have no systemic toxicity and be effective at low drug and light doses. Further, cutaneous photosensitivity appears to persist only 5-7 days.

  7. [An evaluation of the effectiveness of laboratory diagnostic methods for brucellosis].

    PubMed

    Gandara, B; Zheludkov, M M; Chernysheva, M I

    1994-01-01

    The diagnostic value of bacteriological and serological methods for the laboratory diagnosis of brucellosis was studied. In the analysis of milk and cheese specimens Brucella cultures were isolated and differentiated as B.melitensis, biovar I, and B.abortus, biovar 4. In 25.6% of cases B.melitensis culture, biovar 1, was isolated from the blood of persons suspected for brucellosis. The isolation of B.melitensis culture from milk showed that this infective agent migrated from small animals to cattle, which was indicative of a high risk of human infection in the state of Zacatecas, Mexico. The comparative evaluation of serological diagnostic methods (the agglutination test in test tubes, Huddleson's slide test, the acidic rose bengal test and the 2-mercaptoethanol test) showed high sensitivity of rapid tests (Huddleson's test and the rose bengal test in 93.7% and 87.9% of cases respectively). The 2-mercaptoethanol test which gave positive results in 63.8% of cases provided additional information characterizing the course of infections process.

  8. Evaluation of retinoic acid ophthalmic emulsion in dry eye.

    PubMed

    Selek, H; Unlü, N; Orhan, M; Irkeç, M

    2000-01-01

    An oil in water emulsion of 0.01% all-trans-retinoic acid (tretinoin) was prepared and clinically evaluated in dry eye patients. The ophthalmic emulsion consisted of 10% of arachis oil and 90% of the hydrogel of Carbopol 940. To evaluate retinoic acid emulsion clinically, a placebo-controlled, open-labeled, randomized study was performed with 22 dry-eye patients. Symptoms were recorded before and after the treatments. The Schirmer I test, measurement of tear film break-up time (BUT), rose Bengal and fluorescein staining of cornea and conjunctiva, and mucus fern test were done. Retinoic acid did not improve the dryness, photophobia and foreign body sensation more than placebo. Schirmer test and BUT were significantly improved by retinoic acid treatment. Corneal and conjunctival epithelium maintained their characteristics during the use of retinoic acid, as indicated by rose Bengal and fluorescein staining. Ophthalmic emulsion of retinoic acid can be suggested as a promising approach for the treatment of dry eye.

  9. Bovine Serum Albulmin Protein-Templated Silver Nanocluster (BSA-Ag13 ): An Effective Singlet Oxygen Generator for Photodynamic Cancer Therapy.

    PubMed

    Yu, Yong; Geng, Junlong; Ong, Edward Yong Xi; Chellappan, Vijila; Tan, Yen Nee

    2016-10-01

    This paper reports a novel synthesis approach of bovine serum albumin (BSA) protein-templated ultrasmall (<2 nm) Ag nanocluster (NC) with strong singlet oxygen generation capacity for photodynamic therapy (PDT). An atomically precise BSA-Ag 13 NC (i.e., 13 Ag atoms per cluster) is successfully synthesized for the first time by using NaOH-dissolved NaBH 4 solution as the controlling reducing agent. The ubiquitous size of BSA-Ag 13 NC results in unique behaviors of its photoexcited states as characterized by the ultrafast laser spectroscopy using time-correlated single photon counting and transient absorption techniques. In particular, triply excited states can be largely present in the excited BSA-Ag 13 NC and readily sensitized molecular oxygen to produce singlet oxygen ( 1 O 2 ) with a high quantum efficiency (≈1.26 using Rose Bengal as a standard). This value is much higher than its Au analogue (i.e., ≈0.07 for BSA-Au 25 NC) and the commonly available photosensitizers. Due to the good cellular uptake and inherent biocompatibility imparted by the surface protein, BSA-Ag 13 NC can be applied as an effective PDT agent in generating 1 O 2 to kill cancer cell as demonstrated in this study. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Kinetic and mechanistic aspects of sensitized photodegradation of β-lactam antibiotics: microbiological implications.

    PubMed

    Reynoso, E; Nesci, A; Allegretti, P; Criado, S; Biasutti, M A

    2012-01-01

    Amoxicillin (Amx) and cephalexin (Cfx) are β-lactam antibiotics widely used in human and veterinary medicine. Two points of interest surrounding these molecules are the photodegradation of the molecules and their microbiological implications, as well as the persistence and bioaccumulation in the environment which may cause resistance to bacterial strains. The kinetic and mechanistic aspects of the photosensitized degradation of Amx and Cfx have been studied in water at pH 7.4 and 10 by stationary and time-resolved methods. Kinetic evidence indicates that the Rose Bengal-sensitized photooxidation of Amx at pH 7.4 proceeds via O(2)((1)Δ(g)) and O(2•-) mechanisms while at pH 10 the degradation path occurs, principally, via O(2)((1)Δ(g)). For Cfx, this process is attributed to O(2)((1)Δ(g)) and O(2•-). Photoproducts, which arise from the addition of oxygen atoms and subsequent oxidation of the groups -CH(3) to -COOH, were detected. For both antibiotics the bacteriostatic activity decreases in parallel to their photodegradation. The results of this study could potentially help scientists to better understand and predict the photodegradability of these antibiotics on living organisms and in different environmental compartments.

  11. Self-assembled titanium phosphonate nanomaterial having a mesoscopic void space and its optoelectronic application.

    PubMed

    Pramanik, Malay; Patra, Astam K; Bhaumik, Asim

    2013-04-14

    Here we report the synthesis of a new crystalline titanium phosphonate material (HTiP-7) having a self-assembled nanostructure and a mesoscopic void space without the aid of any surfactant or templating agent. The material has been synthesized hydrothermally through the reaction between benzene-1,3,5-triphosphonic acid (BTPA) and titanium(iv) isopropoxide at neutral pH at 453 K for 24 h. This hybrid phosphonate material has been thoroughly characterized by powder X-ray diffraction, N2 sorption, HR TEM, FE SEM, TG-DTA, FT IR and UV-Vis diffuse reflectance spectroscopic studies. Two very well-known software packages, REFLEX and CELSIZ unit cell refinement programs, are employed to establish the triclinic crystal phase of this hybrid material (HTiP-7). Very tiny nanocrystals of HTiP-7 self-aggregated to form spherical nanoparticles of dimension ca. 25 nm together with a mesoscopic void space and good BET surface area (255 m(2) g(-1)). The framework is thermally stable up to 650 K. The material showed excellent carrier mobility for photocurrent generation in the presence of a photosensitizer molecule (Rose Bengal). To the best of our knowledge this is the first report of a photon-to-electron energy transfer process over a dye doped titanium phosphonate nanomaterial.

  12. Concentration-Dependence of Vitamin C in Combinations with Vitamin E and Zeaxanthin on Light-Induced Toxicity to Retinal Pigment Epithelial Cells†

    PubMed Central

    Różanowska, Małgorzata; Bakker, Linda; Boulton, Michael E.; Różanowski, Bartosz

    2012-01-01

    The purpose of this study was to determine the effects of increasing concentration of ascorbate alone and in combinations with α-tocopherol and zeaxanthin on phototoxicity to the retinal pigment epithelium. ARPE-19 cells were exposed to rose bengal and visible light in the presence and absence of antioxidants. Toxicity was quantified by an assay of cell reductive activity. 20 min exposure to visible light and photosensitizer decreased cell viability to ~42%. Lipophilic antioxidants increased viabilities to ~70%, ~61% and ~75% for α-tocopherol, zeaxanthin and their combination, respectively. Cell viabilities were ~70%, 56% and 5% after exposures in the presence of 0.35, 0.7 and 1.4 mM ascorbate, respectively. 45 min exposure increased cell death to ~74% and to >95% in the absence and presence of ascorbate, respectively. In the presence of ascorbate, zeaxanthin did not significantly affect phototoxicity. α-Tocopherol and its combination with zeaxanthin enhanced protective effects of ascorbate but did not prevent from ascorbate-mediated deleterious effects. In conclusion, there is a narrow range of concentrations and exposure times where ascorbate exerts photoprotective effects, exceeding which leads to ascorbate-mediated increase in photocytotoxicity. Vitamin E and its combination with zeaxanthin can enhance protective effects of ascorbate but do not ameliorate its deleterious effects. PMID:22924673

  13. Distance-Dependent Plasmon-Enhanced Singlet Oxygen Production and Emission for Bacterial Inactivation.

    PubMed

    Planas, Oriol; Macia, Nicolas; Agut, Montserrat; Nonell, Santi; Heyne, Belinda

    2016-03-02

    Herein, we synthesized a series of 10 core-shell silver-silica nanoparticles with a photosensitizer, Rose Bengal, tethered to their surface. Each nanoparticle possesses an identical silver core of about 67 nm, but presents a different silica shell thickness ranging from 5 to 100 nm. These hybrid plasmonic nanoparticles thus afford a plasmonic nanostructure platform with a source of singlet oxygen ((1)O2) at a well-defined distance from the metallic core. Via time-resolved and steady state spectroscopic techniques, we demonstrate the silver core exerts a dual role of enhancing both the production of (1)O2, through enhanced absorption of light, and its radiative decay, which in turn boosts (1)O2 phosphorescence emission to a greater extent. Furthermore, we show both the production and emission of (1)O2 in vitro to be dependent on proximity to the plasmonic nanostructure. Our results clearly exhibit three distinct regimes as the plasmonic nanostructure moves apart from the (1)O2 source, with a greater enhancement for silica shell thicknesses ranging between 10 and 20 nm. Moreover, these hybrid plasmonic nanoparticles can be delivered to both Gram-positive and Gram-negative bacteria boosting both photoantibacterial activity and detection limit of (1)O2 in cells.

  14. Tooth color change caused by photosensitizers after photodynamic therapy: An in vitro study.

    PubMed

    Costa, Larissa Menezes; Matos, Felipe de Souza; Correia, Ayla Macyelle de Oliveira; Carvalho, Nayane Chagas; Faria-E-Silva, André Luís; Paranhos, Luiz Renato; Ribeiro, Maria Amália Gonzaga

    2016-07-01

    This study aimed to perform an in vitro evaluation of the effect of photosensitizers used in photodynamic therapy (PDT) on tooth color change when used in combination with conventional endodontic treatment. Forty extracted human mandibular premolars were accessed and underwent root canal therapy and PDT. Photosensitizers were used in accordance with the experimental groups: MB (n=10) - PDT with Methylene Blue at 0.01%; TB (n=10) - PDT with Toluidine Blue at 0.01%; MG (n=10) - PDT with Malachite Green at 0.01%, at the concentration of 0.1mg/mL; and PC (n=10) - positive control, PDT with Endo-PTC cream stained with Methylene Blue at 25%. The samples were irradiated with 660-nm diode laser by means of a 330-μm-diameter optical fiber cable at a power density of 40mW for 120s. After light curing, the photosensitizers were removed from the specimens with 10mL sodium hypochlorite at 1%. A reflectance spectrometer was used for evaluation of color prior to and 60days after the experimental procedure based on the CIE L*a*b* system. According to ANOVA test, there were statistically significant differences between the experimental groups (p=0.003). Tukey's test showed a significant difference between PC and TB (p=0.008), as well as between MG and TB (p=0.009). However, there was no statistically significant difference between PC, MG (p=0.957) and MB (p=0.103). It was concluded that the use of PDT as an adjuvant to root canal therapy, using different photosensitizers, led to color change in tooth structure. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. Methyl pyropheophorbide-a analogues: potential fluorescent probes for the peripheral-type benzodiazepine receptor. Effect of central metal in photosensitizing efficacy.

    PubMed

    Chen, Yihui; Zheng, Xiang; Dobhal, Mahabeer P; Gryshuk, Amy; Morgan, Janet; Dougherty, Thomas J; Oseroff, Allan; Pandey, Ravindra K

    2005-06-02

    Pyropheophorbides and their metal complexes were synthesized to investigate their applications as nonradioactive peripheral benzodiazepine receptor (PBR) binding probes and photosensitizers for use in photodynamic therapy. They were found to be localized in mitochondria and showed significant binding to PBR. In some cases, the PBR binding values were similar to that for 17 (PK11195, 1-(2-chlorophenyl)-N-methyl-N-(1-methylpropyl)isoquinoline-3-carboxamide). However, no direct correlation between 17 displacement ability and photosensitizing efficacy of photosensitizers was observed.

  16. Assessment and Application of the ROSE Code for Reactor Outage Thermal-Hydraulic and Safety Analysis

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liang, Thomas K.S.; Ko, F.-K.; Dai, L.-C

    The currently available tools, such as RELAP5, RETRAN, and others, cannot easily and correctly perform the task of analyzing the system behavior during plant outages. Therefore, a medium-sized program aiming at reactor outage simulation and evaluation, such as midloop operation (MLO) with loss of residual heat removal (RHR), has been developed. Important thermal-hydraulic processes involved during MLO with loss of RHR can be properly simulated by the newly developed reactor outage simulation and evaluation (ROSE) code. The two-region approach with a modified two-fluid model has been adopted to be the theoretical basis of the ROSE code.To verify the analytical modelmore » in the first step, posttest calculations against the integral midloop experiments with loss of RHR have been performed. The excellent simulation capacity of the ROSE code against the Institute of Nuclear Energy Research Integral System Test Facility test data is demonstrated. To further mature the ROSE code in simulating a full-sized pressurized water reactor, assessment against the WGOTHIC code and the Maanshan momentary-loss-of-RHR event has been undertaken. The successfully assessed ROSE code is then applied to evaluate the abnormal operation procedure (AOP) with loss of RHR during MLO (AOP 537.4) for the Maanshan plant. The ROSE code also has been successfully transplanted into the Maanshan training simulator to support operator training. How the simulator was upgraded by the ROSE code for MLO will be presented in the future.« less

  17. Photosensitized singlet oxygen generation and detection: Recent advances and future perspectives in cancer photodynamic therapy.

    PubMed

    Li, Buhong; Lin, Lisheng; Lin, Huiyun; Wilson, Brian C

    2016-12-01

    Photodynamic therapy (PDT) uses photosensitizers and visible light in combination with molecular oxygen to produce reactive oxygen species (ROS) that kill malignant cells by apoptosis and/or necrosis, shut down the tumor microvasculature and stimulate the host immune system. The excited singlet state of oxygen ( 1 O 2 ) is recognized to be the main cytotoxic ROS generated during PDT for the majority of photosensitizers used clinically and for many investigational new agents, so that maximizing its production within tumor cells and tissues can improve the therapeutic response, and several emerging and novel approaches for this are summarized. Quantitative techniques for 1 O 2 production measurement during photosensitization are also of immense importance of value for both preclinical research and future clinical practice. In this review, emerging strategies for enhanced photosensitized 1 O 2 generation are introduced, while recent advances in direct detection and imaging of 1 O 2 luminescence are summarized. In addition, the correlation between cumulative 1 O 2 luminescence and PDT efficiency will be highlighted. Meanwhile, the validation of 1 O 2 luminescence dosimetry for PDT application is also considered. This review concludes with a discussion on future demands of 1 O 2 luminescence detection for PDT dosimetry, with particular emphasis on clinical translation. Eye-catching color image for graphical abstract. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Tetralogy of Fallot and atrial septal defect in a white Bengal Tiger cub (Panthera tigris tigris)

    PubMed Central

    2014-01-01

    A 3-week-old female white Bengal Tiger cub (Panthera tigris tigris) presented with acute onset tachypnoea, cyanosis and hypothermia. The cub was severely hypoxaemic with a mixed acid–base disturbance. Echocardiography revealed severe pulmonic stenosis, right ventricular hypertrophy, high membranous ventricular septal defect and an overriding aorta. Additionally, an atrial septal defect was found on necropsy, resulting in the final diagnosis of Tetralogy of Fallot with an atrial septal defect (a subclass of Pentalogy of Fallot). This report is the first to encompass arterial blood gas analysis, thoracic radiographs, echocardiography and necropsy findings in a white Bengal Tiger cub diagnosed with Tetralogy of Fallot with an atrial septal defect. PMID:24594084

  19. 200,000 years of monsoonal history recorded on the lower Bengal Fan - strong response to insolation forcing

    NASA Astrophysics Data System (ADS)

    Weber, Michael E.; Lantzsch, Hendrik; Dekens, Petra; Das, Supriyo K.; Reilly, Brendan T.; Martos, Yasmina M.; Meyer-Jacob, Carsten; Agrahari, Sandip; Ekblad, Alf; Titschack, Jürgen; Holmes, Beth; Wolfgramm, Philipp

    2018-07-01

    We conducted a multidisciplinary study to provide the stratigraphic and palaeoclimatic context of monsoonal rainfall dynamics and their responses to orbital forcing for the Bay of Bengal. Using sediment lightness we established an age model at orbital resolution for International Ocean Discovery Programme (IODP) Core U1452C-1H that covers the last 200 ka in the lower Bengal Fan. The low-resolution δ18O of G. sacculifer is consistent with global δ18O records, at least for major glacial-to-interglacial transitions. The variability of total organic carbon, total nitrogen, and the δ13C composition of organic matter indicate the marine origin of organic matter. Marine primary productivity likely increased during insolation minima, indicative for an enhanced NE monsoon during glacials and stadials. Pristine insolation forcing is also documented for wet-bulk density, red-green color variability, and grain-size variations, indicating that darker and coarser-grained material deposited at higher sedimentation rates during insolation minima. Stronger NE monsoon likely amplified ocean-atmosphere interactions over the Indian Ocean, leading to stronger upwelling through shoaling the thermocline, and higher delivery of sediment to the Bay of Bengal due to higher soil erosion on land. In addition, lower glacial and stadial sea levels as well as stronger westward surface circulation favored delivery of coarser-grained fluvial material to the lower Bengal Fan. At the same time the stronger NE monsoon might have increased the aeolian supply. Total inorganic carbon, the Ca/Ti ratio, and biogenic silica vary dominantly on obliquity frequencies, suggesting mobilization and transport of lithogenic material primarily during lowered sea levels and/or higher influence of the Northern Hemisphere westerlies on the dust transport from the Tibetan Plateau. The close resemblance of sediment lightness and the climate record of Antarctic ice cores over multiple glacial cycles indicate close

  20. Electrothermal atomic absorption spectrometric determination of arsenic in essential lavender and rose oils.

    PubMed

    Karadjova, Irina B; Lampugnani, Leonardo; Tsalev, Dimiter L

    2005-02-28

    Analytical procedures for electrothermal atomic absorption spectrometric (ETAAS) determination of arsenic in essential oils from lavender (Lavendula angustifolia) and rose (Rosa damascena) are described. For direct ETAAS analysis, oil samples are diluted with ethanol or i-propanol for lavender and rose oil, respectively. Leveling off responses of four different arsenic species (arsenite, arsenate, monomethylarsonate and dimethylarsinate) is achieved by using a composite chemical modifier: l-cysteine (0.05gl(-1)) in combination with palladium (2.5mug) and citric acid (100mug). Transverse-heated graphite atomizer (THGA) with longitudinal Zeeman-effect background correction and 'end-capped' graphite tubes with integrated pyrolytic graphite platforms, pre-treated with Zr-Ir for permanent modification are employed as most appropriate atomizer. Calibration with solvent-matched standard solutions of As(III) is used for four- and five-fold diluted samples of lavender and rose oil, respectively. Lower dilution factors required standard addition calibration by using aqueous (for lavender oil) or i-propanol (for rose oil) solutions of As(III). The limits of detection (LOD) for the whole analytical procedure are 4.4 and 4.7ngg(-1) As in levender and rose oil, respectively. The relative standard deviation (R.S.D.) for As at 6-30ngg(-1) levels is between 8 and 17% for both oils. As an alternative, procedure based on low temperature plasma ashing in oxygen with ETAAS, providing LODs of 2.5 and 2.7ngg(-1) As in levender and rose oil, respectively, and R.S.D. within 8-12% for both oils has been elaborated. Results obtained by both procedures are in good agreement.

  1. Deep sequencing reveals a novel closterovirus associated with wild rose leaf rosette disease.

    PubMed

    He, Yan; Yang, Zuokun; Hong, Ni; Wang, Guoping; Ning, Guogui; Xu, Wenxing

    2015-06-01

    A bizarre virus-like symptom of a leaf rosette formed by dense small leaves on branches of wild roses (Rosa multiflora Thunb.), designated as 'wild rose leaf rosette disease' (WRLRD), was observed in China. To investigate the presumed causal virus, a wild rose sample affected by WRLRD was subjected to deep sequencing of small interfering RNAs (siRNAs) for a complete survey of the infecting viruses and viroids. The assembly of siRNAs led to the reconstruction of the complete genomes of three known viruses, namely Apple stem grooving virus (ASGV), Blackberry chlorotic ringspot virus (BCRV) and Prunus necrotic ringspot virus (PNRSV), and of a novel virus provisionally named 'rose leaf rosette-associated virus' (RLRaV). Phylogenetic analysis clearly placed RLRaV alongside members of the genus Closterovirus, family Closteroviridae. Genome organization of RLRaV RNA (17,653 nucleotides) showed 13 open reading frames (ORFs), except ORF1 and the quintuple gene block, most of which showed no significant similarities with known viral proteins, but, instead, had detectable identities to fungal or bacterial proteins. Additional novel molecular features indicated that RLRaV seems to be the most complex virus among the known genus members. To our knowledge, this is the first report of WRLRD and its associated closterovirus, as well as two ilarviruses and one capilovirus, infecting wild roses. Our findings present novel information about the closterovirus and the aetiology of this rose disease which should facilitate its control. More importantly, the novel features of RLRaV help to clarify the molecular and evolutionary features of the closterovirus. © 2014 BSPP AND JOHN WILEY & SONS LTD.

  2. Photodynamic Cell Killing Effects and Acute Skin Photosensitivity of Aluminum‐chloro‐tetrasulfonated Phthalocyanine and Hematoporphyrin Derivative

    PubMed Central

    Komatsu, Kazuto

    1991-01-01

    Aluminum‐chloro‐tetrasulfonated phthalocyanine (PC) showing an absorption peak at 678 nm was compared to hematoporphyrin derivative (MpD), a photosensitizer commonly used in the photodynamic therapy (PDT) of cancers. In vitro studies: KK‐47 cells were exposed to long‐wavelength ultraviolet (UVA) or red light (>600 nm, >640 nm and >660 nm) after drug sensitization. With UVA irradiation, a higher photodynamic cell killing effect was observed in the cells treated with HpD than with PC. However, with red light irradiation (both > 640 nm and >660 nm) PC resulted in greater cell damage. PC was less toxic to KK‐47 cells in the dark. In vivo studies: Using a gold vapor laser (GVL: 627.8 nm, 200 mW/cm2, 200 J/cm2), the photodynamic tumor response was determined in C3H/He mice bearing transplantable squamous cell carcinoma. No significant difference was observed in the tumor volume between the PC and HpD groups, except that the PC group (10.0 mg/kg body weight) showed a significantly higher remission rate (3/6) than the control group (0/10, P<0.05). Skin Photosensitivity test: Skin photosensitivity was estimated by measuring changes in back skin thickness due to photosensitization. With UVA irradiation, a stronger skin reaction was observed in the HpD group, while with visible light irradiation there was no significant difference between the HpD and PC groups. Based on the superior cell killing effect with red light, reduced toxicity to the cells in the dark and mild skin reaction with UVA, PC may be a more promising photosensitizer for PDT. PMID:1905706

  3. Partial preferential chromosome pairing is genotype dependent in tetraploid rose.

    PubMed

    Bourke, Peter M; Arens, Paul; Voorrips, Roeland E; Esselink, G Danny; Koning-Boucoiran, Carole F S; Van't Westende, Wendy P C; Santos Leonardo, Tiago; Wissink, Patrick; Zheng, Chaozhi; van Geest, Geert; Visser, Richard G F; Krens, Frans A; Smulders, Marinus J M; Maliepaard, Chris

    2017-04-01

    It has long been recognised that polyploid species do not always neatly fall into the categories of auto- or allopolyploid, leading to the term 'segmental allopolyploid' to describe everything in between. The meiotic behaviour of such intermediate species is not fully understood, nor is there consensus as to how to model their inheritance patterns. In this study we used a tetraploid cut rose (Rosa hybrida) population, genotyped using the 68K WagRhSNP array, to construct an ultra-high-density linkage map of all homologous chromosomes using methods previously developed for autotetraploids. Using the predicted bivalent configurations in this population we quantified differences in pairing behaviour among and along homologous chromosomes, leading us to correct our estimates of recombination frequency to account for this behaviour. This resulted in the re-mapping of 25 695 SNP markers across all homologues of the seven rose chromosomes, tailored to the pairing behaviour of each chromosome in each parent. We confirmed the inferred differences in pairing behaviour among chromosomes by examining repulsion-phase linkage estimates, which also carry information about preferential pairing and recombination. Currently, the closest sequenced relative to rose is Fragaria vesca. Aligning the integrated ultra-dense rose map with the strawberry genome sequence provided a detailed picture of the synteny, confirming overall co-linearity but also revealing new genomic rearrangements. Our results suggest that pairing affinities may vary along chromosome arms, which broadens our current understanding of segmental allopolyploidy. © 2017 The Authors The Plant Journal published by John Wiley & Sons Ltd and Society for Experimental Biology.

  4. Political ecology of groundwater: the contrasting case of water-abundant West Bengal and water-scarce Gujarat, India

    NASA Astrophysics Data System (ADS)

    Mukherji, Aditi

    2006-03-01

    Three apparently disparate themes (groundwater, farmers and politics) interweave in this account of how groundwater-related policies in India have very little to do with the scarcity, depletion or quality of groundwater, and more to do with rural politics manifested, among other things, in terms of the presence or absence of farmer lobbies. Examples from two states of India, the water-abundant state of West Bengal and water-scarce state of Gujarat, were investigated using readily available data, analysis of the literature, interviews and fieldwork. In the case of West Bengal, although there is no pressing groundwater crisis, the government of West Bengal (GOWB) was able to successfully implement strict groundwater regulations along with a drastic increase in electricity tariff. More importantly, GOWB was able to implement these without any form of visible farmer protest, though these measures negatively affected farmer incomes. On the other hand, in Gujarat, where there is a real and grave groundwater crisis, the government of Gujarat has neither been able to implement strict groundwater regulations, nor has it been able to increase electricity tariff substantially. Thus, through the lens of ‘political ecology’ the contrasting case of these two Indian states is explained.

  5. Raman microspectroscopy of Hematoporphyrins. Imaging of the noncancerous and the cancerous human breast tissues with photosensitizers.

    PubMed

    Brozek-Pluska, B; Kopec, M

    2016-12-05

    Raman microspectroscopy combined with fluorescence were used to study the distribution of Hematoporphyrin (Hp) in noncancerous and cancerous breast tissues. The results demonstrate the ability of Raman spectroscopy to distinguish between noncancerous and cancerous human breast tissue and to identify differences in the distribution and photodegradation of Hematoporphyrin, which is a photosensitizer in photodynamic therapy (PDT), photodynamic diagnosis (PDD) and photoimmunotherapy (PIT) of cancer. Presented results show that Hematoporphyrin level in the noncancerous breast tissue is lower compared to the cancerous one. We have proved also that the Raman intensity of lipids and proteins doesn't change dramatically after laser light irradiation, which indicates that the PDT treatment destroys preferably cancer cells, in which the photosensitizer is accumulated. The specific subcellular localization of photosensitizer for breast tissues samples soaked with Hematoporphyrin was not observed. Copyright © 2016 Elsevier B.V. All rights reserved.

  6. Use of chloro-aluminum sulfonated phthalocyanine as a photosensitizer in the treatment of malignant tumors in dogs and cats

    NASA Astrophysics Data System (ADS)

    Peavy, George M.; Klein, Mary K.; Newman, H. C.; Roberts, Walter G.; Berns, Michael W.

    1991-05-01

    Chloro-aluminum sulfonated phthalocyanine (CASPc) has been proposed as a photosensitizing agent for photodynamic therapy (PDT) of neoplasia. This paper reviews the results of PDT treatment using CASPc as a photosensitizing agent in the treatment of 15 cats representing 23 sites of facial, solar induced squamous cell carcinoma, 4 dogs with hemangiopericytomas, 3 dogs with fibrosarcomas, and 1 dog with multiple cutaneous mast cell tumors. The results of this study to date suggest that CASPc is a good photosensitizing agent for the treatment of some forms of spontaneously occurring malignant neoplasia and should be more thoroughly evaluated for this purpose.

  7. Investigation on the Bay of Bengal branch of summer monsoon during normal and delayed onset over Gangetic West Bengal

    NASA Astrophysics Data System (ADS)

    Das, Debanjana; Mondal, Paramita; Saha, Poulomi; Chaudhuri, Sutapa

    2018-06-01

    The regional features of Bay of Bengal (BOB) branch of summer monsoon (SM) are examined to identify the causes of delayed onset over Gangetic West Bengal (GWB) in the years having normal onset over Kerala coast. The normal onset over both GWB and Kerala is designated as Normal-Normal (NN) years, while delayed onset over GWB and normal onset over Kerala is termed Normal-Delayed (ND) years. The temperature gradient (TTg), winds at 850 and 150 hPa pressure levels, sea-surface temperature (SST), outgoing long wave radiation (OLR), low-level moisture convergence, instability, and rainfall rate (RR) are analyzed in this study using National Centers for Environmental Prediction and National Oceanic and Atmospheric Administration reanalysis dataset during the period from 1981 to 2015. The result shows that TTg over BOB plays a significant role in controlling the movement of BOB branch of SM. Warm SST is observed to prevail over north BOB during NN years. The divergence at 150 hPa and convergence at 850 hPa pressure levels are found to influence the propagation of BOB branch of SM during both NN and ND years. The winds at 850 hPa level converge over BOB and GWB during NN years, whereas winds converge more over eastern BOB and Indo-Chinese peninsula during ND years. Result depicts abundance of low-level (850-1000 hPa) moisture over eastern BOB and Indo-Chinese peninsula during ND years, whereas moisture is observed to converge over north and north-eastern BOB during NN years. The RR is observed to be slightly higher during NN than ND years. However, it may not be concluded from the analysis that delayed onset over GWB will be responsible for less RR over the study region.

  8. Proteomic Analysis of Aphid-Resistant and -Sensitive Rose (Rosa Hybrida) Cultivars at Two Developmental Stages.

    PubMed

    Muneer, Sowbiya; Jeong, Hai Kyoung; Park, Yoo Gyeong; Jeong, Byoung Ryong

    2018-05-25

    The rose is one the most commercially grown and costly ornamental plants because of its aesthetic beauty and aroma. A large number of pests attack its buds, flowers, leaves, and stem at every growing stage due to its high sugar content. The most common pest on roses are aphids which are considered to be the major cause for product loss. Aphid infestations lead to major changes in rose plants, such as large and irregular holes in petals, intact leaves and devouring tissues. It is hypothesized that different cut rose cultivars would have different levels of sensitivity or resistance to aphids, since different levels of infestation are observed in commercially cut rose production greenhouses. The present work compared four cut rose cultivars which were bred in Korea and were either resistant or sensitive to aphid infestation at different flower developmental stages. An integrative study was conducted using comprehensive proteome analyses. Proteins related to ubiquitin metabolism and the stress response were differentially expressed due to aphid infestation. The regulations and possible functions of identified proteins are presented in detail. The differential expressions of the identified proteins were validated by immunoblotting and blue native page. In addition, total sugar and carbohydrate content were also observed.

  9. Role of Petal-Specific Orcinol O-Methyltransferases in the Evolution of Rose Scent1

    PubMed Central

    Scalliet, Gabriel; Lionnet, Claire; Le Bechec, Mickaël; Dutron, Laurence; Magnard, Jean-Louis; Baudino, Sylvie; Bergougnoux, Véronique; Jullien, Frédéric; Chambrier, Pierre; Vergne, Philippe; Dumas, Christian; Cock, J. Mark; Hugueney, Philippe

    2006-01-01

    Orcinol O-methyltransferase (OOMT) 1 and 2 catalyze the last two steps of the biosynthetic pathway leading to the phenolic methyl ether 3,5-dimethoxytoluene (DMT), the major scent compound of many rose (Rosa x hybrida) varieties. Modern roses are descended from both European and Chinese species, the latter being producers of phenolic methyl ethers but not the former. Here we investigated why phenolic methyl ether production occurs in some but not all rose varieties. In DMT-producing varieties, OOMTs were shown to be localized specifically in the petal, predominanty in the adaxial epidermal cells. In these cells, OOMTs become increasingly associated with membranes during petal development, suggesting that the scent biosynthesis pathway catalyzed by these enzymes may be directly linked to the cells' secretory machinery. OOMT gene sequences were detected in two non-DMT-producing rose species of European origin, but no mRNA transcripts were detected, and these varieties lacked both OOMT protein and enzyme activity. These data indicate that up-regulation of OOMT gene expression may have been a critical step in the evolution of scent production in roses. PMID:16361520

  10. Floral characteristics affect susceptibility of hybrid tea roses, Rosa x hybrida, to Japanese beetles (Coleoptera: Scarabaeidae).

    PubMed

    Held, David W; Potter, Daniel A

    2004-04-01

    The Japanese beetle, Popillia japonica Newman, feeds on the flowers and foliage of roses. Rosa x hybrida. Beetles attracted to roses land almost exclusively on the flowers. This study evaluated characteristics of rose flowers including color, size, petal count and fragrance, as well as height of plants and blooms within plant as factors in attractiveness to Japanese beetles. Artificial flowers that had been painted to match the spectral reflectance of real blooms were attached to potted nonflowering rose plants in the field and the number of beetles that landed on each model was recorded. More beetles landed on the yellow- and white-colored flower models than on the five other bloom colors that were tested. Large (15 cm diameter) yellow flower models attracted more beetles than did smaller (8 cm diameter) yellow models. There was no difference in beetle response to yellow flower models of the same size that differed in bloom complexity (i.e., number of petals). Experiments in which blooming rose plants were elevated above controls, or in which flower models were placed at different heights within plant canopies, failed to support the hypothesis that height per se accounts for beetles' attraction to flowers over leaves. Attractiveness of selected rose cultivars that varied in fragrance and flower color also was evaluated in the field. Yellow-flowered cultivars were more susceptible than those with red flowers, regardless of fragrance intensity as rated by breeders. Growing cultivars of roses that have relatively dark and small-sized blooms may have some benefit in reducing Japanese beetles' attraction to roses.

  11. Quantum Yield of Cyclobutane Pyrimidine Dimer Formation Via the Triplet Channel Determined by Photosensitization.

    PubMed

    Liu, Lizhe; Pilles, Bert M; Gontcharov, Julia; Bucher, Dominik B; Zinth, Wolfgang

    2016-01-21

    UV-induced formation of the cyclobutane pyrimidine dimer (CPD) lesion is investigated by stationary and time-resolved photosensitization experiments. The photosensitizer 2'-methoxyacetophenone with high intersystem crossing efficiency and large absorption cross-section in the UV-A range was used. A diffusion controlled reaction model is presented. Time-resolved experiments confirmed the validity of the reaction model and provided information on the dynamics of the triplet sensitization process. With a series of concentration dependent stationary illumination experiments, we determined the quantum efficiency for CPD formation from the triplet state of the thymine dinucleotide TpT to be 4 ± 0.2%.

  12. Novel type 1 photosensitizers: viability of leukemia cells exposed to reactive intermediates generated in situ by in vitro photofragmentation

    NASA Astrophysics Data System (ADS)

    Rajagopalan, Raghavan; Karwa, Amol; Lusiak, Przemyslaw M.; Srivastava, Kripa; Poreddy, Amruta R.; Pandurangi, Raghootama S.; Galen, Karen P.; Neumann, William L.; Cantrell, Gary E.; Dorshow, Richard B.

    2009-06-01

    Photodynamic therapy of tumors involving Type 2 photosenstizers has been conspicuously successful, but the Type 1 process, in contrast, has not received much attention despite its considerable potential. Accordingly, several classes of molecules containing fragile bonds such as azido (-N=N=N), azo (-N=N-), sulfenato (-S-O-) and oxaza (-N-O-) functional groups that produce reactive intermediates such as radicals and nitrenes upon photoexcitation were prepared and tested for cell viability using U397 leukemia cell line. The azido photosensitizer was conjugated to leukemia cell binding peptide, SFFWRLS, for targeted cell viability study. The cells were incubated with the photosensitizer at various concentrations, and were illuminated for 5, 10, and 20 minutes. The results show that all the photosensitizers caused cell death compared to the controls when exposed to both the photosensitizers and light. Most importantly, selective cell death was observed with the azido peptide conjugate 6, which clearly demonstrates that these Type 1 sensitizers are useful for phototherapeutic applications.

  13. Rebamipide increases the amount of mucin-like substances on the conjunctiva and cornea in the N-acetylcysteine-treated in vivo model.

    PubMed

    Urashima, Hiroki; Okamoto, Takashi; Takeji, Yasuhiro; Shinohara, Hisashi; Fujisawa, Shigeki

    2004-08-01

    Rebamipide increases the amount of mucin-like substances in the stomach. We aimed to determine the effects of rebamipide on the amount of mucin-like substances in the conjunctiva and cornea of N-acetylcysteine-treated eyes. Furthermore, we attempted to evaluate the effects of rebamipide on the wound healing of N-acetylcysteine-treated eyes. The model was created by instilling 10% N-acetylcysteine solutions into rabbit eyes. Rebamipide was then applied on the day following the completion of N-acetylcysteine treatment. The amount of mucin-like substances on the conjunctiva and cornea was measured using the Alcian-blue binding method. The degree of damage was evaluated using scores based on the areas and densities of the cornea and conjunctival after staining using a rose Bengal solution under blind conditions. Rebamipide increased the level of mucin-like substances on the conjunctiva of N-acetylcysteine-treated eyes when instilled at concentrations of 0.3% or higher, and 1% rebamipide increased the amount of mucin-like substances covering the cornea. Moreover, 1% rebamipide improved the rose Bengal scores of the cornea and conjunctiva in N-acetylcysteine-treated eyes. Rebamipide increased mucin-like substances on the cornea and conjunctiva of N-acetylcysteine-treated eyes. In accordance with the mucin-increasing effects, rebamipide improved the rose Bengal scores for the cornea and conjunctiva of N-acetylcysteine-treated eyes. However, the relevance of these findings to dry eyes is unclear because it is not known whether the change in mucus expression in the N-acetylcysteine model is similar to what occurs in aqueous tear deficiency. Consequently, it may be worth trying on an animal model of keratoconjunctivitis sicca.

  14. Minority Enrollments Rose in 1995, Study Finds.

    ERIC Educational Resources Information Center

    Gose, Ben

    1997-01-01

    College student enrollment from the four largest minority groups (American Indians, Asians, Blacks, Hispanics) rose by 2.9% in 1995, accounting for one-quarter of all students. White student enrollments accounted for an overall enrollment decline of 1%, although the proportion of whites aged 18-24 in college reached an all-time high, 43%. Blacks…

  15. Geology and log responses of the Rose Run sandstone in Randolph Township, Portage County, Ohio

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Moyer, C.C.

    1996-09-01

    Approximately 75 wells have penetrated the Cambrian Rose Run sandstone in Randolph Township, Portage County, Ohio, about half of which should produce well beyond economic payout. Only one deep test (to the Rose Run or deeper) was drilled in this Township prior to 1990. Two separate and distinct Rose Run producing fields exist in the Township; the western field is predominately gas-productive and the east is predominantly oil-productive. Both fields are on the north side of the Akron-Suffield Fault Zone, which is part of a regional cross-strike structural discontinuity extending from the Pittsburgh, Pennsylvania area northwestward to Lake Erie. Thismore » feature exhibits control over Berea, Oriskany, Newburg, Clinton, and Rose Run production.« less

  16. Visible-Light-Induced Nickel-Catalyzed Negishi Cross-Couplings by Exogenous-Photosensitizer-Free Photocatalysis.

    PubMed

    Abdiaj, Irini; Fontana, Alberto; Gomez, M Victoria; de la Hoz, Antonio; Alcázar, Jesús

    2018-03-22

    The merging of photoredox and transition-metal catalysis has become one of the most attractive approaches for carbon-carbon bond formation. Such reactions require the use of two organo-transition-metal species, one of which acts as a photosensitizer and the other one as a cross-coupling catalyst. We report herein an exogenous-photosensitizer-free photocatalytic process for the formation of carbon-carbon bonds by direct acceleration of the well-known nickel-catalyzed Negishi cross-coupling that is based on the use of two naturally abundant metals. This finding will open new avenues in cross-coupling chemistry that involve the direct visible-light absorption of organometallic catalytic complexes. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. The Rose Report [Continued]: "The Invisible Worm"

    ERIC Educational Resources Information Center

    Drummond, Mary Jane

    2009-01-01

    While Colin Richards' article is a trenchant analysis of the big themes and missed opportunities of the Rose Report, this response examines some of the small print. It concludes that the document is disfigured by many minor blemishes, and is also fatally flawed by a crude misapprehension of the nature of progress and the purpose of education.

  18. Anticancer activity of the new photosensitizers: dose and cell type dependence

    NASA Astrophysics Data System (ADS)

    Gyulkhandanyan, Grigor V.; Ghambaryan, Sona S.; Amelyan, Gayane V.; Ghazaryan, Robert K.; Haroutiunian, Samvel G.; Gyulkhandanyan, Aram G.; Gasparyan, Gennadi H.

    2005-04-01

    The necessity of researches of antitumor efficiency of new photosensitizers (PS) is explained by the opportunity of their application in photodynamic therapy of tumors. PS, selectively accumulated in cancer cells and activated by the light, generate the active oxygen species that cause apoptosis. Earlier, it was shown that PS chlorin e6 (0.3-0.5 μg/ml) induces rat embryo fibroblast-like cell apoptosis. In present work antitumor activity of the new photosensitizers, water-soluble cationic porphyrins and their metal complexes, is investigated. The dose-dependent destruction of cancer cells was shown on PC-12 (pheochromocytoma, rat adrenal gland) and Jurkat (human lymphoma) cell lines. Meso-tetra-[4-N-(2 `- oxyethyl) pyridyl] porphyrin (TOEPyP) and chlorin e6 possessed the same toxicity at LD50 dose on PC-12 cell line, whereas phototoxicity of TOEPyP was 3 times less compared to chlorin e6(LD50=0.2 and 0.075 μg/ml accordingly). The results have shown weak photosensitizing effect of Zn-and Ag-derivatives of TOEPyP on PC-12 cell line. TOEPyP and Zn-TOEPyP (0.1 - 50 μg/ml) were non-toxic for Jurkat cell line, whereas Ag-TOEPyP was toxic at 10 μg/ml (LD90). TOEPyP and chlorin e6 have shown phototoxic effect in the same dose range (LD50=0.5 and 0.3 μg/ml accordingly). The investigation of toxic and phototoxic effects of the new porphyrins revealed significantly different sensitivity of various cell lines to PSs.

  19. Relationship between summer monsoon rainfall and cyclogenesis over Bay of Bengal during post-monsoon (October-December) season

    NASA Astrophysics Data System (ADS)

    Sadhuram, Y.; Maneesha, K.

    2016-10-01

    In this study, an attempt has been made to examine the relationship between summer monsoon rainfall (June-September) and the total number of depressions, cyclones and severe cyclones (TNDC) over Bay of Bengal during the post-monsoon (October-December) season. The seasonal rainfall of the subdivisions (located in south India) (referred as rainfall index - RI), is positively and significantly correlated ( r=0.59; significant at >99% level) with the TNDC during the period, 1984-2013. By using the first differences (current season minus previous season), the correlations are enhanced and a remarkably high correlation of 0.87 is observed between TNDC and RI for the recent period, 1993-2013. The average seasonal genesis potential parameter (GPP) showed a very high correlation of 0.84 with the TNDC. A very high correlation of 0.83 is observed between GPP and RI for the period, 1993-2013. The relative vorticity and mid-tropospheric relative humidity are found to be the dominant terms in GPP. The GPP was 3.5 times higher in above (below) normal RI in which TNDC was 4 (2). It is inferred that RI is playing a key role in TNDC by modulating the environmental conditions (low level vorticity and relative humidity) over Bay of Bengal during post-monsoon season which could be seen from the very high correlation of 0.87 (which explains 76% variability in TNDC). For the first time, we show that RI is a precursor for the TNDC over Bay of Bengal during post-monsoon season. Strong westerlies after the SW monsoon season transport moisture over the subdivisions towards Bay of Bengal due to cyclonic circulation. This circulation favours upward motion and hence transport moisture vertically to mid-troposphere which causes convective instability and this in turn favour more number of TNDC, under above-normal RI year.

  20. Effectiveness of partially soluble photosensitizer in photodynamic microbiological inactivation: a curcumin example

    NASA Astrophysics Data System (ADS)

    Pratavieira, Sebastião.; Matroodi, Fatima; Pinto-Júnior, Fabio Francisco; Rastelli, Alessandra Nara Souza; Bagnato, Vanderlei S.; Guimarães, Francisco E. G.

    2017-07-01

    We show that partial solubility of a photosensitizer is not necessarily a bad property when dealing with microbiological control. The presence of curcumin aggregates in solution may present advantages with respect the photoand chemical stability.

  1. Fitness benefits of the fruit fly Rhagoletis alternata on a non-native rose host.

    PubMed

    Meijer, Kim; Smit, Christian; Schilthuizen, Menno; Beukeboom, Leo W

    2016-05-01

    Many species have been introduced worldwide into areas outside their natural range. Often these non-native species are introduced without their natural enemies, which sometimes leads to uncontrolled population growth. It is rarely reported that an introduced species provides a new resource for a native species. The rose hips of the Japanese rose, Rosa rugosa, which has been introduced in large parts of Europe, are infested by the native monophagous tephritid fruit fly Rhagoletis alternata. We studied differences in fitness benefits between R. alternata larvae using R. rugosa as well as native Rosa species in the Netherlands. R. alternata pupae were larger and heavier when the larvae fed on rose hips of R. rugosa. Larvae feeding on R. rugosa were parasitized less frequently by parasitic wasps than were larvae feeding on native roses. The differences in parasitization are probably due to morphological differences between the native and non-native rose hips: the hypanthium of a R. rugosa hip is thicker and provides the larvae with the possibility to feed deeper into the hip, meaning that the parasitoids cannot reach them with their ovipositor and the larvae escape parasitization. Our study shows that native species switching to a novel non-native host can experience fitness benefits compared to the original native host.

  2. Brain activation during intermittent photic stimulation: a [15O]-water PET study on photosensitive epilepsy.

    PubMed

    da Silva, E A; Müller, R A; Chugani, D C; Shah, J; Shah, A; Watson, C; Chugani, H T

    1999-01-01

    Intermittent photic stimulation (IPS) is an activation procedure used during electroencephalogram (EEG) recording to elicit paroxysmal discharges in individuals with photosensitivity. Specific responses on EEG recording may be provoked by IPS at different frequencies of flickering in normal individuals and in patients with photosensitive epilepsy. Changes in regional cerebral blood flow (rCBF) were studied during IPS in two groups of subjects by using [15O]-water positron emission tomography (PET): a control group consisting of eight healthy adults with photic driving response during IPS on EEG recording (mean age, 25 +/- 10.5 years) without history of neurologic or psychiatric abnormalities and a patient group consisting of four adults (mean age, 33 +/- 7.5 years) with history of photosensitive epilepsy. [15O]-water PET scanning with concomitant EEG monitoring was performed during baseline and IPS at 4-, 14-, and 30-Hz frequencies. The control group showed photic driving response at 14-Hz IPS frequency. The patient group showed photoparoxysmal response at 14 and 30 Hz, but not at 4 Hz. Changes in rCBF were determined by means of statistical parametric mapping. Increases in rCBF in occipital cortex (Brodmann's areas 17, 18, and 19) were observed in both groups. In addition, during photic driving responses, the control group showed rCBF increases in the insula and in the thalamus, on the right side. The patient group showed a significant rCBF increase in the hypothalamic region inferior to the left caudate nucleus during photoparoxysmal response. This activation was not found in the control group. Increased rCBF also was observed in the patient group in the head of the left caudate nucleus, in the left hippocampus, and in left insula during IPS without photoparoxysmal response. No activations in these regions were observed during photoparoxysmal response. These data may indicate involvement of the hypothalamus in photosensitive epilepsy and may suggest a modulatory

  3. Electrospun photosensitive nanofibers: potential for photocurrent therapy in skin regeneration.

    PubMed

    Jin, Guorui; Prabhakaran, Molamma P; Kai, Dan; Kotaki, Masaya; Ramakrishna, Seeram

    2013-01-01

    Poly(3-hexylthiophene) (P3HT) is one of the most promising photovoltaic (PV) polymers in photocurrent therapy. A novel photosensitive scaffold for skin tissue engineering was fabricated by blending P3HT with polycaprolactone (PCL) and electrospun to obtain composite PCL/P3HT nanofibers with three different weight ratios of PCL : P3HT (w/w) of 150 : 2 [PCL/P3HT(2)], 150 : 10 [PCL/P3HT(10)] and 150 : 20 [PCL/P3HT(20)]. The photosensitive properties of the blend solutions and the composite nanofibers of PCL/P3HT were investigated. The incident photon-to-electron conversion efficiencies of the PCL/P3HT(2), PCL/P3HT(10), PCL/P3HT(20) were identified as 2.0 × 10(-6), 1.6 × 10(-5) and 2.9 × 10(-5), respectively, which confirm the photosensitive ability of the P3HT-containing scaffolds. The biocompatibility of the scaffold was evaluated by culturing human dermal fibroblasts and the results showed that the proliferation of HDFs under light stimulation on PCL/P3HT(10) was 12.8%, 11.9%, and 11.6% (p ≤ 0.05) higher than the cell growth on PCL, PCL/P3HT(2) and PCL/P3HT(20), respectively. Human dermal fibroblasts cultured under light stimulation on PCL/P3HT(10) not only showed better cell proliferation but also retained cell morphology similar to the phenotype observed on tissue culture plates (control). Our experimental results suggest novel and potential application of an optimized amount of P3HT-containing scaffold, especially PCL/P3HT(10) nanofibrous scaffold in photocurrent therapy for skin regeneration.

  4. Novel method for in vitro depletion of T cells by monoclonal antibody-targeted photosensitization.

    PubMed

    Berki, T; Németh, P

    1998-02-01

    An immunotargeting method (called photo-immunotargeting) has been developed for selective in vitro cell destruction. The procedure combines the photosensitizing (toxic) effect of light-induced dye-molecules, e.g., hematoporphyrin (HP) and the selective binding ability of monoclonal antibodies (mAb) to cell surface molecules. The photosensitizer HP molecules were covalently attached to monoclonal antibodies (a-Thy-1) recognizing an antigen on the surface of T lymphocytes, and used for T cell destruction. To increase the selectivity of the conventional targeting methods, a physical activation step (local light irradiation) as a second degree of specificity was employed. The HP in conjugated form was sufficient to induce T cell (thymocytes, EL-4 cell line) death after irradiation at 400 nm, at tenfold lower concentration compared to the photosensitizing effect of unbound HP. The selective killing of T lymphocytes (bearing the Thy-1 antigen) in a mixed cell population was demonstrated after a treatment with the phototoxic conjugate and light irradiation. This method can be useful for selective destruction of one population (target cell) in an in vitro heterogeneous cell mixture, e.g., in bone marrow transplants for T cell depletion to avoid graft vs. host reaction.

  5. Pyropheophorbide-a methyl ester-mediated photosensitization activates transcription factor NF-kappaB through the interleukin-1 receptor-dependent signaling pathway.

    PubMed

    Matroule, J Y; Bonizzi, G; Morlière, P; Paillous, N; Santus, R; Bours, V; Piette, J

    1999-01-29

    Pyropheophorbide-a methyl ester (PPME) is a second generation of photosensitizers used in photodynamic therapy. We demonstrated that PPME photosensitization activated NF-kappaB transcription factor in colon cancer cells. Unexpectedly, this activation occurred in two separate waves, i.e. a rapid and transient one and a second slower but sustained phase. The former was due to photosensitization by PPME localized in the cytoplasmic membrane which triggered interleukin-1 receptor internalization and the transduction pathways controlled by the interleukin-1 type I receptor. Indeed, TRAF6 dominant negative mutant abolished NF-kappaB activation by PPME photosensitization, and TRAF2 dominant negative mutant was without any effect, and overexpression of IkappaB kinases increased gene transcription controlled by NF-kappaB. Oxidative stress was not likely involved in the activation. On the other hand, the slower and sustained wave could be the product of the release of ceramide through activation of the acidic sphingomyelinase. PPME localization within the lysosomal membrane could explain why ceramide acted as second messenger in NF-kappaB activation by PPME photosensitization. These data will allow a better understanding of the molecular basis of tumor eradication by photodynamic therapy, in particular the importance of the host cell response in the treatment.

  6. Determination of free and esterified carotenoid composition in rose hip fruit by HPLC-DAD-APCI(+)-MS.

    PubMed

    Zhong, Lijie; Gustavsson, Karl-Erik; Oredsson, Stina; Głąb, Bartosz; Yilmaz, Jenny Lindberg; Olsson, Marie E

    2016-11-01

    Rose hip fruit, which contains high concentration of carotenoids is commonly used for different food products in Europe and it is considered to have medical properties. In this study, a simple, rapid and efficient HPLC-DAD-APCI(+)-MS method was developed and applied to identify and quantify the carotenoids in rose hip fruit of four rose species, including both unsaponified and saponified extract. In the unsaponified extract 23 carotenoid esters were detected, in which either rubixanthin ester or violaxanthin ester was the dominant component of the ester composition. In the saponified extract 21 carotenoids, including 11 xanthophylls and 10 carotenes were detected. This is the first time the total carotenoid composition, including the carotenoid esters in rose hip fruit were identified and quantified. This work reveals the potential of rose hip fruit to be utilized as a healthy dietary material and give chemical information for the possible future development in the pharmacology field. Copyright © 2016 Elsevier Ltd. All rights reserved.

  7. Bay of Bengal Surface and Thermocline and the Arabian Sea

    DTIC Science & Technology

    2014-09-30

    to the atmosphere. How low the SSS gets in the Bay of Bengal or how high in the Arabian Sea, depends on the oceanic exchanges between them via a...potential impact on the SST. 3 Figure 1a: Sea surface temperature (SST) and salinity ( SSS ) relationship during ASIRI 2013 cruises. The left panel...shows the hull ADCP vector, color-coded for SSS . The SST/ SSS scatter falls along a line from the warm/salty southern regions to the cool/fresher

  8. Evaluation of chronic arsenic poisoning due to consumption of contaminated ground water in West Bengal, India.

    PubMed

    Ghosh, Asutosh

    2013-08-01

    Chronic arsenic poisoning is an important public health problem and most notable in West Bengal and Bangladesh. In this study different systemic manifestations in chronic arsenic poisoning were evaluated. A nonrandomized, controlled, cross-sectional, observational study was carried out in Arsenic Clinic, Institute of Postgraduate Medical Education and Research, Kolkata, West Bengal, over a period of 1 year 4 months. Seventy-three cases diagnosed clinically, consuming water containing arsenic ≥50 μg/L and having hair and nail arsenic level >0.6 μg/L, were included. Special investigations included routine parameters and organ-specific tests. Arsenic levels in the drinking water, hair, and nail were measured in all. Twenty-five nonsmoker healthy controls were evaluated. Murshidabad and districts adjacent to Kolkata, West Bengal, were mostly affected. Middle-aged males were the common sufferers. Skin involvement was the commonest manifestation (100%), followed by hepatomegaly [23 (31.5%)] with or without transaminitis [7 (9.58%)]/portal hypertension [9 (12.33%)]. Restrictive abnormality in spirometry [11 (15.06%)], bronchiectasis [4 (5.47%)], interstitial fibrosis [2 (2.73%)], bronchogenic carcinoma [2 (2.73%)], oromucosal plaque [7 (9.58%)], nail hypertrophy [10 (13.69%)], alopecia [8 (10.95%)], neuropathy [5 (6.84%)], and Electrocardiography abnormalities [5 (6.84%)] were also observed. Mucocutaneous and nail lesions, hepatomegaly, and restrictive change in spirometry were the common and significant findings. Other manifestations were characteristic but insignificant.

  9. First report of Seuratascaris numidica Seurat, 1917 (Nematoda: Ascarididae) and other helminths from amphibians of West Bengal, India.

    PubMed

    Sou, Sujan K; Bursey, Charles R

    2017-03-01

    Studies on nematode parasites from anuran hosts from Eastern India, particularly West Bengal, are rare. To our knowledge, there is a report of larvae of Monhysterides sp. (a fish parasite) from cysts within the body cavity and musculature of Duttaphrynus melanostictus, Hoplobatrachus tigerinus and Euphlyctis hexadactylus as well as descriptions of Aplectana duttaphryni from D. melanostictus , Aplectana dubrajpuri from H. tigerinus , Cosmocerca microhylae from Microhyla rubra and Rhabdias bulbicauda from D. melanostictus . Here, we report mature individuals of typical anuran parasites, Diplodiscus amphichrus and Seuratascaris numidica , from H. tigerinus and larvae of Acuariidae (a bird parasite) from Fejervarya limnocharis collected in Kulti, West Bengal.

  10. A theoretical study of a series of water-soluble triphenylamine photosensitizers for two-photon photodynamic therapy.

    PubMed

    Wang, Xin; Yin, Xue; Lai, Xiao-Yong; Liu, Ying-Tao

    2018-10-05

    In this study, the therapeutic activity of a series of water-soluble triphenylamine (TP) photosensitizers (Ps) was explored by using theoretical simulations. The key photophysical parameters which determined the efficiency of Ps, such as absorption electronic spectra, singlet-triplet energy gaps and spin-orbit matrix elements were calculated at density functional theory and its time-dependent extension (DFT, TD-DFT). The calculated results showed that these TP photosensitizers possessed large two-photon absorption cross-section in the near-infrared region (NIR), efficient intersystem crossing (ISC) transition from the first singlet excited state to the low lying triplet excited states and sufficient energy for generating reactive oxygen species (ROS). These suitable features made these TP series holding great promise for applications in two-photon photodynamic therapy (PDT). These TP photosensitizers studied here in principle extended the application range of two-photon PDT in water solution. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Functional PET Evaluation of the Photosensitive Baboon

    PubMed Central

    Szabó, C. Ákos; Salinas, Felipe S; Narayana, Shalini

    2011-01-01

    The baboon provides a unique, natural model of epilepsy in nonhuman primates. Additionally, photosensitivity of the epileptic baboon provides an important window into the mechanism of human idiopathic generalized epilepsies. In order to better understand the networks underlying this model, our group utilized functional positron emission tomography (PET) to compare cerebral blood flow (CBF) changes occurring during intermittent light stimulation (ILS) and rest between baboons photosensitive, epileptic (PS) and asymptomatic, control (CTL) animals. Our studies utilized subtraction and covariance analyses to evaluate CBF changes occurring during ILS across activation and resting states, but also evaluated CBF correlations with ketamine doses and interictal epileptic discharge (IED) rate during the resting state. Furthermore, our group also assessed the CBF responses related to variation of ILS in PS and CTL animals. CBF changes in the subtraction and covariance analyses reveal the physiological response and visual connectivity in CTL animals and pathophysiological networks underlying responses associated with the activation of ictal and interictal epileptic discharges in PS animals. The correlation with ketamine dose is essential to understanding differences in CBF responses between both groups, and correlations with IED rate provides an insight into an epileptic network independent of visual activation. Finally, the ILS frequency dependent changes can help develop a framework to study not only spatial connectivity but also the temporal sequence of regional activations and deactivations related to ILS. The maps generated by the CBF analyses will be used to target specific nodes in the epileptic network for electrophysiological evaluation using intracranial electrodes. PMID:22276085

  12. Primary photosensitization caused by ingestion of Froelichia humboldtiana by dairy goats.

    PubMed

    Santos, Danielle S; Silva, Caio C B; Araújo, Valber O; de Fátima Souza, Maria; Lacerda-Lucena, Patrícia B; Simões, Sara V D; Riet-Correa, Franklin; Lucena, Ricardo B

    2017-01-01

    This study aimed to describe the first report of an outbreak of primary photosensitization in dairy goats caused by Froelichia humboldtiana. The disease occurred from March to May 2014, in a mixed flock of 15 Saanen, Alpine, and crossbred lactating goats. The entire flock was affected; however, the Saanen and cross-bred goats developed more severe lesions, and their milk production decreased by as much as 75%. Lesions were progressive and consisted of skin hyperemia, edema, and necrosis, especially in depigmented areas. An experimental study with two goats resulted in photodermatitis, similar to that observed in the natural cases, 10-14 days after the beginning of plant ingestion. Serum activities of aspartate aminotransferase (AST) and -glutamyltransferase (GGT) and, direct, indirect, and total bilirubin serum concentrations were within the normal ranges. In conclusion, F. humboldtiana causes primary photosensitization in goats with a negative impact on milk production. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Air-sea CO2 flux pattern along the southern Bay of Bengal waters

    NASA Astrophysics Data System (ADS)

    Shanthi, R.; Poornima, D.; Naveen, M.; Thangaradjou, T.; Choudhury, S. B.; Rao, K. H.; Dadhwal, V. K.

    2016-12-01

    Physico-chemical observations made from January 2013 to March 2015 in coastal waters of the southwest Bay of Bengal show pronounced seasonal variation in physico-chemical parameters including total alkalinity (TA: 1927.390-4088.642 μmol kg-1), chlorophyll (0.13-19.41 μg l-1) and also calculated dissolved inorganic carbon (DIC: 1574.219-3790.954 μmol kg-1), partial pressure of carbon dioxide (pCO2: 155.520-1488.607 μatm) and air-sea CO2 flux (FCO2: -4.808 to 11.255 mmol Cm-2 d-1). Most of the physical parameters are at their maximum during summer due to the increased solar radiation at cloud free conditions, less or no riverine inputs, and lack of vertical mixing of water column which leads to the lowest nutrients concentration, dissolved oxygen (DO), biological production, pCO2 and negative flux of CO2 to the atmosphere. Chlorophyll and DO concentrations enhanced due to increased nutrients during premonsoon and monsoon season due to the vertical mixing of water column driven by the strong winds and external inputs at respective seasons. The constant positive loading of nutrients, TA, DIC, chlorophyll, pCO2 and FCO2 against atmospheric temperature (AT), lux, sea surface temperature (SST), pH and salinity observed in principal component analysis (PCA) suggested that physical and biological parameters play vital role in the seasonal distribution of pCO2 along the southwest Bay of Bengal. The annual variability of CO2 flux clearly depicted that the southwest Bay of Bengal switch from sink (2013) to source status in the recent years (2014 and 2015) and it act as significant source of CO2 to the atmosphere with a mean flux of 0.204 ± 1.449 mmol Cm-2 d-1.

  14. Downy mildew of Double Knock Out® rose caused by Peronospora sparsa in Maryland

    USDA-ARS?s Scientific Manuscript database

    Roses are one of the most popular and economically important ornamental plants worldwide. In the last 17 years, Knock Out® roses (Rosa x 'Radtko') have been widely used in public and private gardens across the U.S. due to their disease resistance, self-cleaning, drought tolerance and multiple-bloomi...

  15. Estimation of Geotropic Currents in the Bay of Bengal using In-situ Observations.

    NASA Astrophysics Data System (ADS)

    T, V. R.

    2014-12-01

    Geostraphic Currents (GCs) can be estimated from temperature and salinity observations. In this study an attempt has been made to compute GC using temperature and salinity observations from Expendable Bathy Thermograph (XBT) and CTD over Bay of Bengal (BoB). Although in recent time we have Argo observations but it is for a limited period and coarse temporal resolutions. In BoB Bengal, where not enough simultaneous hydrographic temperature and salinity data are available with reasonable spatial resolution (~one degree spatial resolution) and for a longer period. To overcome the limitations of GC computed from XBT profiles, temperature-salinity relationships were used from simultaneous temperature and salinity observations. We have demonstrated that GCs can be computed with an accuracy of less than 8.5 cm/s (root mean square error) at the surface with respect to temperature from XBT and salinity from climatological record. This error reduces with increasing depth. Finally, we demonstrated the application of this approach to study the temporal variation of the GCs during 1992 to 2012 along an XBT transect.

  16. Suppression of cucurbit scab on cucumber leaves by photodynamic dyes

    USDA-ARS?s Scientific Manuscript database

    The goal of this study was to test the ability of the photodynamic dyes bengal rose, toluidine blue, and methylene blue, to protect systemically cucumber plants from cucurbit scab. At the stage of one true leaf, water or aqueous solutions of the dyes were applied to the leaf as droplets. When the se...

  17. Assembly of catalase-based bioconjugates for enhanced anticancer efficiency of photodynamic therapy in vitro.

    PubMed

    Zhao, Jie; Fei, Jinbo; Du, Cuiling; Cui, Wei; Ma, Hongchao; Li, Junbai

    2013-11-25

    An oxygen generation core-shell structure uploading rose bengal has been fabricated by covalent assembly of catalase and alginate dialdehyde via Schiff's base. The composite can catalyze the decomposition of intracellular H2O2 to increase the concentration of O2, which effectively enhances the anticancer efficiency of photodynamic therapy in vitro.

  18. Anti-prediabetic effect of rose hip (Rosa canina) extract in spontaneously diabetic Torii rats.

    PubMed

    Chen, Si Jing; Aikawa, Chiwa; Yoshida, Risa; Kawaguchi, Tomoaki; Matsui, Toshiro

    2017-09-01

    Prediabetes, a high-risk state for developing diabetes showing impaired glucose tolerance but a normal fasting blood glucose level, has an increasing prevalence worldwide. However, no study investigating the prevention of impaired glucose tolerance at the prediabetic stage by anti-diabetic functional foods has been reported. Thus, the present study aimed to evaluate the anti-prediabetic effect of rose hip in a prediabetic rat model. Spontaneously diabetic Torii (SDT) rats were supplemented with hot-water extract of rose hip at a dose of 100 mg kg -1 body weight day -1 for 12 weeks. The results obtained showed that the supplementation of rose hip extract improved impaired glucose tolerance, promoted insulin secretion, preserved pancreatic beta-cell function and suppressed plasma advanced glycation end-products formation of methylglyoxal-derived hydroimidazolone (MG-H1) residue and N ϵ -carboxymethyl-lysine residues (e.g. MG-H1, control: 465.5 ± 43.8 versus rose hip: 59.1 ± 13.0 pmol mg protein -1 , P < 0.05) in SDT rats at the prediabetic stage (12-20 weeks old). The present study provides the first evidence showing that a hot-water extract of rose hip could exert an anti-prediabetic effect in a rat model. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  19. Abdominal pythiosis in a Bengal tiger (Panthera tigris tigris).

    PubMed

    Buergelt, Claus; Powe, Joshua; White, Tamara

    2006-06-01

    An adult Bengal tiger (Panthera tigris tigris) housed in an outdoor sanctuary in Florida exhibited vomiting, diarrhea, and weight loss. A clinical workup did not reveal the source of the clinical signs and antibiotic therapy was unrewarding. Radiographs revealed the presence of an abdominal mass. The tiger died during an immobilization for a follow-up clinical examination. A necropsy was performed and tissue samples of intestine and mesenteric lymph nodes were submitted for histopathologic diagnosis. A pyogranulomatous panenteritis and lymphadenitis with intralesional hyphae led to a presumptive etiologic diagnosis of intestinal/abdominal pythiosis. The diagnosis of pythiosis was confirmed by serology and immunoblotting.

  20. Panel of polymorphic heterologous microsatellite loci to genotype critically endangered Bengal tiger: a pilot study.

    PubMed

    Mishra, Sudhanshu; Singh, Sujeet Kumar; Munjal, Ashok Kumar; Aspi, Jouni; Goyal, Surendra Prakash

    2014-01-03

    In India, six landscapes and source populations that are important for long-term conservation of Bengal tigers (Panthera tigris tigris) have been identified. Except for a few studies, nothing is known regarding the genetic structure and extent of gene flow among most of the tiger populations across India as the majority of them are small, fragmented and isolated. Thus, individual-based relationships are required to understand the species ecology and biology for planning effective conservation and genetics-based individual identification has been widely used. But this needs screening and describing characteristics of microsatellite loci from DNA from good-quality sources so that the required number of loci can be selected and the genotyping error rate minimized. In the studies so far conducted on the Bengal tiger, a very small number of loci (n = 35) have been tested with high-quality source of DNA, and information on locus-specific characteristics is lacking. The use of such characteristics has been strongly recommended in the literature to minimize the error rate and by the International Society for Forensic Genetics (ISFG) for forensic purposes. Therefore, we describe for the first time locus-specific genetic and genotyping profile characteristics, crucial for population genetic studies, using high-quality source of DNA of the Bengal tiger. We screened 39 heterologous microsatellite loci (Sumatran tiger, domestic cat, Asiatic lion and snow leopard) in captive individuals (n = 8), of which 21 loci are being reported for the first time in the Bengal tiger, providing an additional choice for selection. The mean relatedness coefficient (R = -0.143) indicates that the selected tigers were unrelated. Thirty-four loci were polymorphic, with the number of alleles ranging from 2 to 7 per locus, and the remaining five loci were monomorphic. Based on the PIC values (> 0.500), and other characteristics, we suggest that 16 loci (3 to 7 alleles) be used for genetic

  1. Sanctified madness: the God-intoxicated saints of Bengal.

    PubMed

    Morinis, A

    1985-01-01

    The saintly madman is a familiar character in South Asia. To outer appearances he is no different from a lunatic, but the mad saint comes to be revered because his idiocy is popularly believed to arise from a different cause than ordinary madness. The common psychopath neglects social conventions because his consciousness is dimmed by incapacity; the saintly madman also breaches convention, but does so because his heightened consciousness has liberated him from the bonds of convention that entrap ordinary people. In the terms of Hinduism, he has tasted the divine nectar of God-realization and has returned to the human realm intoxicated by the experience. In this paper two popular God intoxicated saints of Bengal are discussed. The question is posed whether 'God intoxication' can be considered a culture-bound syndrome of Bengal. The concept of 'culture bound syndrome' is found to be too narrow to encompass the most significant issues to arise from reflection on the characteristics of the God intoxicated. These larger issues have to do with the relationship between cultural practices and models and mental states (whether deviant, as implied by the term 'syndrome' although deviance does not always carry the negative connotation implicit in 'syndrome', or normal). It is suggested that all cultures culture a limited range of mental states and thus the questions posed by the notion of culture bound syndromes are subsumed by larger questions about the relationship of all mind-states to the socio-cultural environment which conditions them. The conclusion is that God intoxication is indeed a uniquely Bengali mental condition, with variants throughout South Asia and kinship to other mystical states, but that the concept of 'syndrome' is not useful.

  2. Study of Photosensitive Dry Films Absorption for Printed Circuit Boards by Photoacoustic Technique

    NASA Astrophysics Data System (ADS)

    Hernández, R.; Zaragoza, J. A. Barrientos; Jiménez-Pérez, J. L.; Orea, A. Cruz; Correa-Pacheco, Z. N.

    2017-08-01

    In this work, the study of photosensitive dry-type films by photoacoustic technique is proposed. The dry film photoresist is resistant to chemical etching for printed circuit boards such as ferric chloride, sodium persulfate or ammonium, hydrochloric acid. It is capable of faithfully reproducing circuit pattern exposed to ultraviolet light (UV) through a negative. Once recorded, the uncured portion is removed with alkaline solution. It is possible to obtain good results in surface mount circuits with tracks of 5 mm. Furthermore, the solid resin films are formed by three layers, two protective layers and a UV-sensitive optical absorption layer in the range of 325 nm to 405 nm. By means of optical absorption of UV-visible rays emitted by a low-power Xe lamp, the films transform this energy into thermal waves generated by the absorption of optical radiation and subsequently no-radiative de-excitation occurs. The photoacoustic spectroscopy is a useful technique to measure the transmittance and absorption directly. In this study, the optical absorption spectra of the three layers of photosensitive dry-type films were obtained as a function of the wavelength, in order to have a knowledge of the absorber layer and the protective layers. These analyses will give us the physical properties of the photosensitive film, which are very important in curing the dry film for applications in printed circuit boards.

  3. Light-driven photosensitizer uptake increases Candida albicans photodynamic inactivation.

    PubMed

    Romano, Renan A; Pratavieira, Sebastião; Silva, Ana P da; Kurachi, Cristina; Guimarães, Francisco E G

    2017-11-01

    Photodynamic Inactivation (PDI) is based on the use of a photosensitizer (PS) and light that results mainly in the production of reactive oxygen species, aiming to produce microorganism cell death. PS incubation time and light dose are key protocol parameters that influence PDI response; the correct choice of them can increase the efficiency of inactivation. The results of this study show that a minor change in the PDI protocol, namely light-driven incubation leads to a higher photosensitizer and more uniform cell uptake inside the irradiated zone. Furthermore, as the uptake increases, the damage caused by PDI also increases. The proposed light-driven incubation prior to the inactivation illumination dose has advantages when compared to the traditional PDI treatments since it can be more selective and effective. Using a violet light as pre-illumination (light-driven incubation) source and a red-light system as PDI source, it was possible to demonstrate that when compared to the traditional protocol of dark incubation, the pre-illuminated cell culture showed an inactivation increase of 7 log units. These in vitro results performed in Candida albicans cells may result in the introduction of a new protocol for PDI. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Therapeutic Applications of Rose Hips from Different Rosa Species.

    PubMed

    Mármol, Inés; Sánchez-de-Diego, Cristina; Jiménez-Moreno, Nerea; Ancín-Azpilicueta, Carmen; Rodríguez-Yoldi, María Jesús

    2017-05-25

    Rosa species, rose hips, are widespread wild plants that have been traditionally used as medicinal compounds for the treatment of a wide variety of diseases. The therapeutic potential of these plants is based on its antioxidant effects caused by or associated with its phytochemical composition, which includes ascorbic acid, phenolic compounds and healthy fatty acids among others. Over the last few years, medicinal interest in rose hips has increased as a consequence of recent research that has studied its potential application as a treatment for several diseases including skin disorders, hepatotoxicity, renal disturbances, diarrhoea, inflammatory disorders, arthritis, diabetes, hyperlipidaemia, obesity and cancer. In this review, the role of different species of Rosa in the prevention of treatment of various disorders related to oxidative stress, is examined, focusing on new therapeutic approaches from a molecular point of view.

  5. Therapeutic Applications of Rose Hips from Different Rosa Species

    PubMed Central

    Mármol, Inés; Sánchez-de-Diego, Cristina; Jiménez-Moreno, Nerea; Ancín-Azpilicueta, Carmen; Rodríguez-Yoldi, María Jesús

    2017-01-01

    Rosa species, rose hips, are widespread wild plants that have been traditionally used as medicinal compounds for the treatment of a wide variety of diseases. The therapeutic potential of these plants is based on its antioxidant effects caused by or associated with its phytochemical composition, which includes ascorbic acid, phenolic compounds and healthy fatty acids among others. Over the last few years, medicinal interest in rose hips has increased as a consequence of recent research that has studied its potential application as a treatment for several diseases including skin disorders, hepatotoxicity, renal disturbances, diarrhoea, inflammatory disorders, arthritis, diabetes, hyperlipidaemia, obesity and cancer. In this review, the role of different species of Rosa in the prevention of treatment of various disorders related to oxidative stress, is examined, focusing on new therapeutic approaches from a molecular point of view. PMID:28587101

  6. Discontinuous/continuous metal films grown on photosensitive glass

    NASA Astrophysics Data System (ADS)

    Trotter, D. M., Jr.; Smith, D. W.

    1984-07-01

    A new effect which allows direct formation of thin metal films of controlled morphology is described. Patterns of glass-ceramic opal are developed in photosensitive glass samples by UV irradiation and heat treatment. The samples are then ion exchanged in molten salt baths containing Ag+ or Cu+ ions. On subsequent firing in a hydrogen atmosphere, continuous films with typical thin metal films properties grow on the opal regions of the samples. Discontinuous films, characterized by activated resistivities and switching, grow on the glassy regions.

  7. Exogenous indirect photoinactivation of bacterial pathogens and indicators in water with natural and synthetic photosensitizers in simulated sunlight with reduced UVB.

    PubMed

    Maraccini, P A; Wenk, J; Boehm, A B

    2016-08-01

    To investigate the UVB-independent and exogenous indirect photoinactivation of eight human health-relevant bacterial species in the presence of photosensitizers. Eight bacterial species were exposed to simulated sunlight with greatly reduced UVB light intensity in the presence of three synthetic photosensitizers and two natural photosensitizers. Inactivation curves were fit with shoulder log-linear or first-order kinetic models, from which the presence of a shoulder and magnitude of inactivation rate constants were compared. Eighty-four percent reduction in the UVB light intensity roughly matched a 72-95% reduction in the overall bacterial photoinactivation rate constants in sensitizer-free water. With the UVB light mostly reduced, the exogenous indirect mechanism contribution was evident for most bacteria and photosensitizers tested, although most prominently with the Gram-positive bacteria. Results confirm the importance of UVB light in bacterial photoinactivation and, with the reduction of the UVB light intensity, that the Gram-positive bacteria are more vulnerable to the exogenous indirect mechanism than Gram-negative bacteria. UVB is the most important range of the sunlight spectrum for bacterial photoinactivation. In aquatic environments where photosensitizers are present and there is high UVB light attenuation, UVA and visible wavelengths can contribute to exogenous indirect photoinactivation. © 2016 The Society for Applied Microbiology.

  8. Photosensitive graphene transistors.

    PubMed

    Li, Jinhua; Niu, Liyong; Zheng, Zijian; Yan, Feng

    2014-08-20

    High performance photodetectors play important roles in the development of innovative technologies in many fields, including medicine, display and imaging, military, optical communication, environment monitoring, security check, scientific research and industrial processing control. Graphene, the most fascinating two-dimensional material, has demonstrated promising applications in various types of photodetectors from terahertz to ultraviolet, due to its ultrahigh carrier mobility and light absorption in broad wavelength range. Graphene field effect transistors are recognized as a type of excellent transducers for photodetection thanks to the inherent amplification function of the transistors, the feasibility of miniaturization and the unique properties of graphene. In this review, we will introduce the applications of graphene transistors as photodetectors in different wavelength ranges including terahertz, infrared, visible, and ultraviolet, focusing on the device design, physics and photosensitive performance. Since the device properties are closely related to the quality of graphene, the devices based on graphene prepared with different methods will be addressed separately with a view to demonstrating more clearly their advantages and shortcomings in practical applications. It is expected that highly sensitive photodetectors based on graphene transistors will find important applications in many emerging areas especially flexible, wearable, printable or transparent electronics and high frequency communications. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Intercomparison of Air-Sea Fluxes in the Bay of Bengal

    NASA Astrophysics Data System (ADS)

    Buckley, J.; Weller, R. A.; Farrar, J. T.; Tandon, A.

    2016-02-01

    Heat and momentum exchange between the air and sea in the Bay of Bengal is an important driver of atmospheric convection during the Asian Monsoon. Warm sea surface temperatures resulting from salinity stratified shallow mixed layers trigger widespread showers and thunderstorms. In this study, we compare atmospheric reanalysis flux products to air-sea flux values calculated from shipboard observations from four cruises and an air-sea flux mooring in the Bay of Bengal as part of the Air-Sea Interactions in the Northern Indian Ocean (ASIRI) experiment. Comparisons with months of mooring data show that most long timescale reanalysis error arises from the overestimation of longwave and shortwave radiation. Ship observations and select data from the air-sea flux mooring reveals significant errors on shorter timescales (2-4 weeks) which are greatly influenced by errors in shortwave radiation and latent and sensible heat. During these shorter periods, the reanalyses fail to properly show sharp decreases in air temperature, humidity, and shortwave radiation associated with mesoscale convective systems. Simulations with the Price-Weller-Pinkel (PWP) model show upper ocean mixing and deepening mixed layers during these events that effect the long term upper ocean stratification. Mesoscale convective systems associated with cloudy skies and cold and dry air can reduce net heat into the ocean for minutes to a few days, significantly effecting air-sea heat transfer, upper ocean stratification, and ocean surface temperature and salinity.

  10. [A case of anaphylaxis due to rose-flavored soft-serve ice cream with pollen food allergy syndrome].

    PubMed

    Kitabayashi, Taeru; Sato, Sayuri; Adachi, Mitsuru

    2013-05-01

    We experienced a 10-year-old boy who had anaphylaxis after eating rose-flavored soft-serve ice cream. The patient felt a sense of discomfort in his throat when eating apple, peach, loquat, Japanese pear, and kiwi fruit. Therefore, we measured specific IgE antibodies to allergen components by ImmunoCAP ISAC. Consequently, the patient gave positive results for all PR-10 proteins from birch, alder, hazel, apple, peach, peanut, hazelnut, and soybean, so we diagnosed him with Pollen Food Allergy Syndrome (PFAS) induced by cross reactivity with pollens of birch family and fruits of rose family. When we conducted the skin prick test as is for red rose syrup because of the belief that anaphylaxis was caused by the rose ingredient contained in rose-flavored soft-serve ice cream, the patient gave a strong positive result. However, the results were negative for rose essence and Food Red No. 2 contained. Subsequently, it was found that red rose syrup contained apple juice. Therefore, we conducted the prick-prick test for apple, and the patient was confirmed to be strongly positive to apple. We thus identified apple as the cause of anaphylaxis. Since there is no legal obligation of labeling specific raw materials when directly selling manufactured and processed food products to general consumers, it is possible for general consumers to mistakenly take them in without knowing the containment of allergic substances. It is believed that the labeling method should be improved in the future.

  11. Student Interests--The German and Austrian ROSE Survey

    ERIC Educational Resources Information Center

    Elster, Doris

    2007-01-01

    ROSE (the Relevance of Science Education) is an international comparative study on the factors which influence learning in science. For this study, the interests, opinions and attitudes of young people were polled by using a standardised questionnaire. Initial data, empirically gathered from 1247 students at the end of lower secondary level in…

  12. Case control study of dry eye and related ocular surface abnormalities in Ibadan, Nigeria.

    PubMed

    Bekibele, C O; Baiyeroju, A M; Ajaiyeoba, A; Akang, E E U; Ajayi, B G K

    2010-02-01

    Tear instability is associated with symptoms of ocular discomfort and irritation. Many patients with dry eyes remain untreated due to improper diagnoses. To identify symptoms and surface abnormalities associated with dry eyes. One hundred and fifty-six eyes of 78 subjects attending the Eye Clinic of the University College Hospital Ibadan were screened for dry eyes/tear instability using rose Bengal stain (graded 0-9), tear break-up time (TBUT), Schirmer's 1 tests, tear meniscus height and a standardised symptoms questionnaire. Grades 4-9 rose Bengal staining were considered as positive dry eye and were compared with grades 0-3 staining eyes as negative controls. Mean tear meniscus height, Schirmer's test and TBUT were lower among cases than their corresponding control eyes. The difference between the mean Schirmer's test values of cases and their controls were statistically significant (P = 0.00 for right eyes and P = 0.002 for left eyes). Rose Bengal grades were inversely correlated with the mean Schirmer's values (Pearson correlation -0.429, P = 0.05 for right eyes and -0.335, P = 0.03 for left eyes) and TBUT (Pearson correlation -0.316, P = 0.05 for right eyes and -0.212, P = 0.06 for left eyes). About 95.8% of the cases were symptomatic, as opposed to 70.4% of the controls (P = 0.01, Fisher's exact test) and 95.8% of dry right eyes compared to 61.1% of their controls had ocular surface abnormalities (P = 0.001), while 89.5% of dry left eyes compared to 62.7% of controls had surface abnormalities (P = 0.07). A close relationship exists between ocular irritation symptoms, surface abnormalities and functional evidence of tear instability. Such patients should be treated empirically or screened for dry eyes.

  13. Release of Membrane-associated Mucins from Ocular Surface Epithelia

    PubMed Central

    Blalock, Timothy D.; Spurr-Michaud, Sandra J.; Tisdale, Ann S.; Gipson, Ilene K.

    2008-01-01

    Purpose Three membrane-associated mucins (MAMs)—MUC1, MUC4 and MUC16—are expressed at the ocular surface epithelium. Soluble forms of MAMs are detected in human tears, but the mechanisms of their release from the apical cells are unknown. The purpose of this study was to identify physiologic agents that induce ocular surface MAM release. Methods An immortalized human corneal-limbal epithelial cell line (HCLE) expressing the same MAMs as native tissue was used. An antibody specific to MUC16’s cytoplasmic tail was developed to confirm that only the extracellular domain is released into the tear fluid or culture media. Effects of agents that have been shown to be present in tears or are implicated in release/shedding of MAMs in other epithelia (neutrophil elastase, tumor necrosis factor (TNF), TNF-α-converting enzyme, and matrix metalloproteinases-7 and –9) were assessed on HCLE cells. HCLE cell surface proteins were biotinylated to measure efficiency of induced MAM release and surface restoration. Effects of induced release on surface barrier function were measured by rose bengal dye penetrance. Results MUC16 in tears and in HCLE-conditioned medium lacked the cytoplasmic tail. TNF induced release of MUC1, MUC4, and MUC16 from the HCLE surface. Matrix metalloproteinase-7 and neutrophil elastase induced release of MUC16 but not MUC1 or MUC4. Neutrophil elastase removed 68% of MUC16—78% of which was restored to the HCLE cell surface 24 hours after release. Neutrophil elastase-treated HCLE cells showed significantly reduced rose bengal dye exclusion. Conclusions Results suggest that extracellular domains of MUC1, 4, and 16 can be released from the ocular surface by agents present in tears. Neutrophil elastase and TNF present in higher amounts in dry eye patients’ tears may cause MAM release—allowing rose bengal staining. PMID:18436821

  14. Antimicrobial photodynamic therapy with two photosensitizers on two oral streptococci: an in vitro study

    NASA Astrophysics Data System (ADS)

    Vahabi, S.; Fekrazad, R.; Ayremlou, S.; Taheri, S.; Lizarelli, R. F. Z.; Kalhori, K. A. M.

    2011-12-01

    Periodontal diseases are caused by infection of tissues supporting the teeth due to complex aggregate of bacteria known as biofilm and firstly colonized by streptococci. The aim of this in vitro study was to evaluate the effect of Radachlorin® and Toluidine Blue O (TBO)-mediated photodynamic therapy (PDT) on the viability of two oral streptococci. Bacterial suspensions of Streptococcus mutans and Streptococcus sanguis were subjected to either TBO or Radachlorin®, Then exposed to two different diode laser light at energy densities of 3, 6 J/cm2 at 633 nm and 6, 12 J/cm2 at 662 nm, respectively. The control groups were subjected to laser light alone, photosensitizer alone or received neither photosensitizer nor light exposure. The suspensions were then spread over specific agar mediums and viable microorganisms were counted after overnight incubation aerobically at 37°C, 5% CO2 and then reported as colony forming unit. The results indicated that photosensitization by the energy density of 6 J/cm2 with Radachlorin® and both 3 and 6 J/cm2 with TBO caused significant reduction in bacterial colony formation ( p < 0.05). Radachlorin® and TBO-mediated photodynamic therapy seem to show excellent potential in significantly killing of two oral streptococci in vitro.

  15. Spectrometric characteristics and tumor-affinity of a novel photosensitizer: mono-l-aspartyl aurochlorin e6 (Au-NPe6).

    PubMed

    Ishizumi, Taichiro; Aizawa, Katsuo; Tsuchida, Takaaki; Okunaka, Tetsuya; Kato, Harubumi

    2004-12-01

    Photodiagnosis and photodynamic therapy with photosensitizers can be indicated only for tumors of the superficial type, because these approaches utilizing visible light are limited by said light penetrability. To overcome this disadvantage, we innovated a novel photosensitizer, mono-l-aspartyl aurochlorin e6 (Au-NPe6), by incorporating a gold atom in the center of tetrapyrrole ring of NPe6 with a coordination bond. The gold atom in Au-NPe6 plays a role as an X-ray interceptor to detect deeply sited tumors. In this study, the absorption spectrum of novel Au-NPe6 in the diagnosis of deeply sited tumors was investigated, and the results were compared with the parent photosensitizer NPe6. Furthermore, the tumor-affinity of Au-NPe6 was evaluated using atomic absorption spectrometry. Despite the fact that both photosensitizers display a difference in the absorption spectrum, waveform changes of either photosensitizer with human serum albumin established a saturation point at a molar ratio of 1:1. The results indicate that it is highly possible that Au-NPe6 bound with albumin at a molar ratio (1:1) similar to NPe6. The accumulation rate of gold in tumor tissues was always significantly (p<0.05) higher than that in normal muscle tissues during the observation terms. Moreover, absorption spectra of tumor-tissue homogenates obtained from tumor-bearing mice after Au-NPe6 administration revealed a common peak with a wavelength equivalent to that of albumin-bond Au-NPe. This result suggests that the gold atom and NPe6 probably remained bonded even when Au-NPe6 was incorporated in tumor tissues.

  16. Nanoencapsulation of Rose-Hip Oil Prevents Oil Oxidation and Allows Obtainment of Gel and Film Topical Formulations.

    PubMed

    Contri, Renata V; Kulkamp-Guerreiro, Irene C; da Silva, Sheila Janine; Frank, Luiza A; Pohlmann, Adriana R; Guterres, Silvia S

    2016-08-01

    The rose-hip oil holds skin regenerating properties with applications in the dermatological and cosmetic area. Its nanoencapsulation might favor the oil stability and its incorporation into hydrophilic formulations, besides increasing the contact with the skin and prolonging its effect. The aim of the present investigation was to develop suitable rose-hip-oil-loaded nanocapsules, to verify the nanocapsule effect on the UV-induced oxidation of the oil and to obtain topical formulations by the incorporation of the nanocapsules into chitosan gel and film. The rose-hip oil (500 or 600 μL), polymer (Eudragit RS100®, 100 or 200 mg), and acetone (50 or 100 mL) contents were separately varied aiming to obtain an adequate size distribution. The results led to a combination of the factors acetone and oil. The developed formulation showed average diameter of 158 ± 6 nm with low polydispersity, pH of 5.8 ± 0.9, zeta potential of +9.8 ± 1.5 mV, rose-hip oil content of 54 ± 1 μL/mL and tendency to reversible creaming. No differences were observed in the nanocapsules properties after storage. The nanoencapsulation of rose-hip oil decreased the UVA and UVC oxidation of the oil. The chitosan gel and film containing rose-hip-oil-loaded nanocapsules showed suitable properties for cutaneous use. In conclusion, it was possible to successfully obtain rose-hip-oil-loaded nanocapsules and to confirm the nanocapsules effect in protecting the oil from the UV rays. The chitosan gel and film were considered interesting alternatives for incorporating the nanoencapsulated rose-hip oil, combining the advantages of the nanoparticles to the advantages of chitosan.

  17. Lipid composition affects the rate of photosensitized dissipation of cross-membrane diffusion potential on liposomes

    PubMed Central

    Ytzhak, Shany; Wuskell, Joseph P.; Loew, Leslie M.; Ehrenberg, Benjamin

    2010-01-01

    Hydrophobic or amphiphilic tetrapyrrole sensitizers are taken up by cells and are usually located in cellular lipid membranes. Singlet oxygen is photogenerated by the sensitizer and it diffuses in the membrane and causes oxidative damage to membrane components. This damage can occur to membrane lipids and to membrane-localized proteins. Depolarization of the Nernst electric potential on cells’ membranes has been observed in cellular photosensitization, but it was not established whether lipid oxidation is a relevant factor leading to abolishing the resting potential of cells’ membranes and to their death. In this work we studied the effect of liposomes’ lipid composition on the kinetics of hematoporphyrin-photosensitized dissipation of K+-diffusion electric potential that was generated across the membranes. We employed an electrochromic voltage-sensitive spectroscopic probe that possesses a high fluorescence signal response to the potential. We found a correlation between the structure and unsaturation of lipids and the leakage of the membrane, following photosensitization. As the extent of non-conjugated unsaturation of the lipids is increased from 1 to 6 double bonds, the kinetics of depolarization become faster. We also found that the kinetics of depolarization is affected by the percentage of the unsaturated lipids in the liposome: as the fraction of the unsaturated lipids increases the leakage trough the membrane is enhanced. When liposomes are composed of a lipid mixture similar to that of natural membranes and photosensitization is being carried out under usual photodynamic therapy (PDT) conditions, photodamage to the lipids is not likely to cause enhanced permeability of ions through the membrane, which would have been a mechanism that leads to cell death. PMID:20536150

  18. Risk of arsenic exposure from drinking water and dietary components: implications for risk management in rural Bengal.

    PubMed

    Halder, Dipti; Bhowmick, Subhamoy; Biswas, Ashis; Chatterjee, Debashis; Nriagu, Jerome; Guha Mazumder, Debendra Nath; Šlejkovec, Zdenka; Jacks, Gunnar; Bhattacharya, Prosun

    2013-01-15

    This study investigates the risk of arsenic (As) exposure to the communities in rural Bengal, even when they have been supplied with As safe drinking water. The estimates of exposure via dietary and drinking water routes show that, when people are consuming water with an As concentration of less than 10 μg L(-1), the total daily intake of inorganic As (TDI-iAs) exceeds the previous provisional tolerable daily intake (PTDI) value of 2.1 μg day(-1) kg(-1) BW, recommended by the World Health Organization (WHO) in 35% of the cases due to consumption of rice. When the level of As concentration in drinking water is above 10 μg L(-1), the TDI-iAs exceeds the previous PTDI for all the participants. These results imply that, when rice consumption is a significant contributor to the TDI-iAs, supplying water with an As concentration at the current national drinking water standard for India and Bangladesh would place many people above the safety threshold of PTDI. We also found that the consumption of vegetables in rural Bengal does not pose a significant health threat to the population independently. This study suggests that any effort to mitigate the As exposure of the villagers in Bengal must consider the risk of As exposure from rice consumption together with drinking water.

  19. A novel, visible light-induced, rapidly cross-linkable gelatin scaffold for osteochondral tissue engineering

    PubMed Central

    Mazaki, Tetsuro; Shiozaki, Yasuyuki; Yamane, Kentaro; Yoshida, Aki; Nakamura, Mariko; Yoshida, Yasuhiro; Zhou, Di; Kitajima, Takashi; Tanaka, Masato; Ito, Yoshihiro; Ozaki, Toshifumi; Matsukawa, Akihiro

    2014-01-01

    Osteochondral injuries remain difficult to repair. We developed a novel photo-cross-linkable furfurylamine-conjugated gelatin (gelatin-FA). Gelatin-FA was rapidly cross-linked by visible light with Rose Bengal, a light sensitizer, and was kept gelled for 3 weeks submerged in saline at 37°C. When bone marrow-derived stromal cells (BMSCs) were suspended in gelatin-FA with 0.05% Rose Bengal, approximately 87% of the cells were viable in the hydrogel at 24 h after photo-cross-linking, and the chondrogenic differentiation of BMSCs was maintained for up to 3 weeks. BMP4 fusion protein with a collagen binding domain (CBD) was retained in the hydrogels at higher levels than unmodified BMP4. Gelatin-FA was subsequently employed as a scaffold for BMSCs and CBD-BMP4 in a rabbit osteochondral defect model. In both cases, the defect was repaired with articular cartilage-like tissue and regenerated subchondral bone. This novel, photo-cross-linkable gelatin appears to be a promising scaffold for the treatment of osteochondral injury. PMID:24662725

  20. Photosensitizer quantitation in vivo by flourescence microsampling

    NASA Astrophysics Data System (ADS)

    Pogue, Brian W.; Burke, Gregory C.; Lee, Claudia C.; Hoopes, P. Jack

    2000-06-01

    Photodynamic therapy can provide a reliable method of tumor destruction when the appropriate dosimetry is applied. Current dosimetry practice involves quantification of the drug and light doses applied to the tumor, but it would be desirable to monitor in vivo light and drug levels to provide the most accurate determination of dosimetry. In vivo measurements can be used to minimize variations in treatment response due to inter-animal variability, by providing animal-specific or patient-specific treatment planning. This study reports on the development of a micro-sampling method to measure fluorescence from tissue, which is not significantly affected by the tissue optical properties. The system measures fluorescence from the surface of a tissue, using a fiber bundle composed of individual 100 micron fibers which ar all spaced apart by 700 microns from one another at the tissue contact end. This design provides sampling of the fluorescence at multiple sites to increase the signal intensity, while maintaining a micro- sampling of the tissue volume just below the surface. The calibration studies here indicate that the 1/e sampling depth is near 60 microns when measured in optical phantoms, which are similar to typical tissue properties. The probe fluorescence signal is independent of blood concentration up to a maximum of 10% blood by volume, which is similar to most tumor tissue. Animal tests indicate that the sensitivity to drug concentration is essentially the same in when measured in murine liver and muscle tissues, both in vivo and ex vivo. These preliminary calibration results suggest that the probe can be used to measure photosensitizer uptake in vivo non- invasively and rapidly via conversion of fluorescence intensity to photosensitizer concentration.

  1. Effect of soybean lecithin on iron-catalyzed or chlorophyll-photosensitized oxidation of canola oil emulsion.

    PubMed

    Choe, Jeesu; Oh, Boyoung; Choe, Eunok

    2014-11-01

    The effect of soybean lecithin addition on the iron-catalyzed or chlorophyll-photosensitized oxidation of emulsions consisting of purified canola oil and water (1:1, w/w) was studied based on headspace oxygen consumption using gas chromatography and hydroperoxide production using the ferric thiocyanate method. Addition levels of iron sulfate, chlorophyll, and soybean lecithin were 5, 4, and 350 mg/kg, respectively. Phospholipids (PLs) during oxidation of the emulsions were monitored by high performance liquid chromatography. Addition of soybean lecithin to the emulsions significantly reduced and decelerated iron-catalyzed oil oxidation by lowering headspace oxygen consumption and hydroperoxide production. However, soybean lecithin had no significant antioxidant effect on chlorophyll-photosensitized oxidation of the emulsions. PLs in soybean lecithin added to the emulsions were degraded during both oxidation processes, although there was little change in PL composition. Among PLs in soybean lecithin, phosphatidylethanolamine and phosphatidylinositol were degraded the fastest in the iron-catalyzed and the chlorophyll-photosensitized oxidation, respectively. The results suggest that addition of soybean lecithin as an emulsifier can also improve the oxidative stability of oil in an emulsion. © 2014 Institute of Food Technologists®

  2. Strengthening Software Authentication with the ROSE Software Suite

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    White, G

    2006-06-15

    Many recent nonproliferation and arms control software projects include a software authentication regime. These include U.S. Government-sponsored projects both in the United States and in the Russian Federation (RF). This trend toward requiring software authentication is only accelerating. Demonstrating assurance that software performs as expected without hidden ''backdoors'' is crucial to a project's success. In this context, ''authentication'' is defined as determining that a software package performs only its intended purpose and performs said purpose correctly and reliably over the planned duration of an agreement. In addition to visual inspections by knowledgeable computer scientists, automated tools are needed to highlightmore » suspicious code constructs, both to aid visual inspection and to guide program development. While many commercial tools are available for portions of the authentication task, they are proprietary and not extensible. An open-source, extensible tool can be customized to the unique needs of each project (projects can have both common and custom rules to detect flaws and security holes). Any such extensible tool has to be based on a complete language compiler. ROSE is precisely such a compiler infrastructure developed within the Department of Energy (DOE) and targeted at the optimization of scientific applications and user-defined libraries within large-scale applications (typically applications of a million lines of code). ROSE is a robust, source-to-source analysis and optimization infrastructure currently addressing large, million-line DOE applications in C and C++ (handling the full C, C99, C++ languages and with current collaborations to support Fortran90). We propose to extend ROSE to address a number of security-specific requirements, and apply it to software authentication for nonproliferation and arms control projects.« less

  3. [Participation of oxygen in the reduction of methylviologen, photosensitized by chlorophyll, in an aqueous solution of detergent].

    PubMed

    Luganskaia, A N; Krasnovskiĭ, A A

    1975-01-01

    Dependence of chlorophyll "a" photosensitized reduction of methylviologene with tiourea on the temperature of reaction mixture was studied in aerobic conditions in triton X-100 aqueous solution. It was found that the reaction consisted of two stages: the light and dark ones. Photosensitized oxidation of tiourea with air oxygen proceeds at the temperatures up to -70 degrees C. Reduction of methylviologen is a dark stage for which diffusion processes are necessary. The role of hydrogen peroxide in the reaction studied has been investigated. It has been shown that hydrogen peroxide is not the "initiator" of the reaction which results in the reduction of methylviologen. Reduced glutation and the mixture of reduced and oxidized glutations were used as electron donors in photosensitized reaction in the presence of air oxygen. An increase of the depth and rate of the reduction of methylviologen under aerobic conditions as compared to anaerobic ones points to the formation of more active reducers than the initial electron donor.

  4. Genome structure of Rosa multiflora, a wild ancestor of cultivated roses

    PubMed Central

    Nakamura, Noriko; Hirakawa, Hideki; Sato, Shusei; Otagaki, Shungo; Matsumoto, Shogo; Tabata, Satoshi; Tanaka, Yoshikazu

    2018-01-01

    Abstract The draft genome sequence of a wild rose (Rosa multiflora Thunb.) was determined using Illumina MiSeq and HiSeq platforms. The total length of the scaffolds was 739,637,845 bp, consisting of 83,189 scaffolds, which was close to the 711 Mbp length estimated by k-mer analysis. N50 length of the scaffolds was 90,830 bp, and extent of the longest was 1,133,259 bp. The average GC content of the scaffolds was 38.9%. After gene prediction, 67,380 candidates exhibiting sequence homology to known genes and domains were extracted, which included complete and partial gene structures. This large number of genes for a diploid plant may reflect heterogeneity of the genome originating from self-incompatibility in R. multiflora. According to CEGMA analysis, 91.9% and 98.0% of the core eukaryotic genes were completely and partially conserved in the scaffolds, respectively. Genes presumably involved in flower color, scent and flowering are assigned. The results of this study will serve as a valuable resource for fundamental and applied research in the rose, including breeding and phylogenetic study of cultivated roses. PMID:29045613

  5. Highly enhanced ultraviolet photosensitivity and recovery speed in electrospun Ni-doped SnO2 nanobelts

    NASA Astrophysics Data System (ADS)

    Huang, Siya; Matsubara, Kohei; Cheng, Jing; Li, Heping; Pan, Wei

    2013-09-01

    Precisely controlled Ni-doped SnO2 (NSO) nanobelt arrays are synthesized and assembled via electrospinning. In comparison to pristine SnO2 nanobelts, enhanced photosensitivity (˜103) as well as recovery speed (˜1 s) is obtained in NSO nanobelts. The mechanism is clarified by the compensation effect of acceptor impurity Ni, which not only promotes the oxygen-surface interaction but also introduces trapping centers in SnO2 matrix. The reduced grain size (˜4 nm) along with increased depletion layer thickness also benefits the photosensitivity of NSO nanobelts. These improved photoresponse properties make the NSO nanobelt a promising candidate for high-performance ultraviolet detectors.

  6. The NPe6 fluorescence measurements by using a fluorescence sensing system for skin photosensitivity risk assessment after photodynamic therapy

    NASA Astrophysics Data System (ADS)

    Ohtani, Keishi; Usuda, Jitsu; Ogawa, Emiyu; Maehara, Sachio; Imai, Kentaro; Inoue, Tatsuya; Hagiwara, Masaru; Kakihana, Masatoshi; Kajiwara, Naohiro; Ohira, Tatsuo; Arai, Tsunenori; Ikeda, Norihiko

    2018-02-01

    Background: Skin photosensitivity is a major side effect of photodynamic therapy (PDT). It is induced by the photosensitizer remaining in the skin. It is usually rapidly metabolized by the liver, but the pharmacokinetic profile varies widely among individuals. This makes it difficult to predict the incidence of skin photosensitivity. Therefore, we conducted a prospective study to investigate whether the NPe6 fluorescence intensity in skin after NPe6-PDT could be measured safely in human patients using a fluorescence sensing system for judging the risk of skin photosensitivity. Methods: The NPe6 fluorescence measurements using a constructed fluorescence sensing system at the inside of the arm were acquired prior to and 5 and 10 minutes after NPe6 administration as well as at the time of PDT (4-5 hours after administration), at discharge (2 or 3 days after PDT), and at 1 or 2 weeks after PDT. Participants were interviewed as to whether they had any complications at 2 weeks after PDT. Results: Nine male patients and one female patient entered this study. All of the measurements of NPe6 fluorescence in the skin could be obtained without any complications. The spectral peak was detected at the time of discharge (2-3 days after administration) in most cases and it decreased at 1 or 2 weeks after PDT. Conclusions: The fluorescence of NPe6 in the skin could be detected feasibly using the fluorescence sensing system in human patients. Measuring fluorescence intensity in the skin might be useful to predict the incidence of skin photosensitivity after PDT.

  7. New photosensitive systems for volume phase holography

    NASA Astrophysics Data System (ADS)

    Bianco, Andrea; Colella, Letizia; Galli, Paola; Zanutta, Alessio; Bertarelli, Chiara

    2017-05-01

    Volume phase holographic elements are becoming attractive thanks to the large efficiency and good optical quality. They are based on photosensitive materials where a modulation of the refractive index is induced. In this paper, we highlight the strategies to obtain a change in the refractive index in a dielectric material, namely a change in the material density and/or in the molecular polarizability. Moreover, we show the results achieved for materials that undergo the photo-Fries reaction as function of the molecular structure and the illumination conditions. We also report the results on a system based on the diazo Meldrum's acid where volatile molecules are produced upon light exposure.

  8. Allogenic and Autogenic Signals in the Detrital Zircon U-Pb Record of the Deep-Sea Bengal Fan

    NASA Astrophysics Data System (ADS)

    Blum, M. D.; Rogers, K. G.; Gleason, J. D.; Najman, Y.

    2017-12-01

    The Himalayan-sourced Ganges-Brahmaputra river system and the deep-sea Bengal Fan represent Earth's largest sediment-dispersal system. This presentation summarizes a new detrital zircon U-Pb (DZ) provenance record from the Bengal Fan from cores collected during IODP Expedition 354, with coring sites located 1350 km downdip from the shelf margin. Each of our 15 samples were collected from medium- to fine-grained turbidite sand and, based on shipboard biostratigraphic analyses, our samples are late Miocene to late Pleistocene in age. Each sample was analyzed by LA-ICPMS at the Arizona Laserchron facility, with an average of n=270 concordant U-Pb ages per sample. Our goals are to use these data to evaluate the influence of allogenic controls vs. autogenic processes on signal propagation from source-to-sink. At the first order, large-scale sediment transfer to the Bengal Fan clearly records the strong tectonic and climatic forcing associated with the Himalayas and Ganges-Brahmaputra system: after up to 2500 km of river transport, and 1350 km of transport in turbidity currents, the DZ record faithfully represents Himalayan source terrains. The sand-rich turbidite part of the record is nevertheless biased towards glacial periods when rivers extended across the shelf in response to climate-forced sea-level fall, and discharged directly to slope canyons. However, only part of the Bengal Fan DZ record represents either the Ganges or the Brahmaputra, with most samples representing varying degrees of mixing of sediments from the two systems: this mixing, or the lack thereof, represents the signal of autogenic avulsions on the delta plain that result in the two river systems delivering sediment separately to the shelf margin, or together as they do today. Within the allogenic framework established by tectonic processes, the climatic system, and global climate-forced sea-level change, the DZ U-Pb record of sediment mixing or the lack thereof provides a fingerprint of autogenic

  9. Cytogenetic, cytotoxic and GC-MS studies on concrete and absolute oils from Taif rose, Saudi Arabia.

    PubMed

    Hagag, Heba A; Bazaid, Salih A; Abdel-Hameed, El-Sayed S; Salman, Mahmood

    2014-12-01

    Taif rose (Rosa damascena trigintipetala Dieck) is a sort of damask rose, which is considered as one of the most important economic products of Taif. In this study, the authors investigated the possible cytotoxic, genotoxic, antimutagenic and anticancer effect of concrete and absolute rose oils. The results showed that both concrete and absolute rose oils were cytotoxically and genotoxically safe at a dose of 10 μg/ml when tested on cultures of normal human blood lymphocytes. Also, the results showed significant antimutagenic activity at p < 0.001 for absolute rose oil at the same dose level when tested on cultures of normal human blood lymphocytes supplemented with 300 ng/ml mitomycin C (MMC). On the other hand, concrete and absolute oils exerted a cytotoxic activity against two kinds of human cancer cell lines: HepG2 and MCF7. Concrete oil showed cytotoxic activity against HepG2 and MCF7 with a half maximal inhibitory concentration (IC50) of 16.28 and 18.09 μg/ml, respectively, whereas absolute rose oil showed its cytotoxic activity against HepG2 and MCF7 with an IC50 of 24.94 and 19.69, respectively. From this study, it is concluded that concrete and absolute rose oils are cytotoxically and genotoxically safe at a dose of 10 μg/ml when tested on cultures of normal human blood lymphocytes. In addition, absolute oil has an antimutagenic activity at the same dose. Further investigations are needed to study the activity of higher doses of both oils in vitro and in vivo in experimental animals in order to evaluate the capability of using these oils as therapeutic for treatment of some kinds of cancers.

  10. Fe N-Heterocyclic Carbene Complexes as Promising Photosensitizers.

    PubMed

    Liu, Yizhu; Persson, Petter; Sundström, Villy; Wärnmark, Kenneth

    2016-08-16

    The photophysics and photochemistry of transition metal complexes (TMCs) has long been a hot field of interdisciplinary research. Rich metal-based redox processes, together with a high variety in electronic configurations and excited-state dynamics, have rendered TMCs excellent candidates for interconversion between light, chemical, and electrical energies in intramolecular, supramolecular, and interfacial arrangements. In specific applications such as photocatalytic organic synthesis, photoelectrochemical cells, and light-driven supramolecular motors, light absorption by a TMC-based photosensitizer and subsequent excited-state energy or electron transfer constitute essential steps. In this context, TMCs based on rare and expensive metals, such as ruthenium and iridium, are frequently employed as photosensitizers, which is obviously not ideal for large-scale implementation. In the search for abundant and environmentally benign solutions, six-coordinate Fe(II) complexes (Fe(II)L6) have been widely considered as highly desirable alternatives. However, not much success has been achieved due to the extremely short-lived triplet metal-to-ligand charge transfer ((3)MLCT) excited state that is deactivated by low-lying metal-centered (MC) states on a 100 fs time scale. A fundamental strategy to design useful Fe-based photosensitizers is thus to destabilize the MC states relative to the (3)MLCT state by increasing the ligand field strength, with special focus on making eg σ* orbitals on the Fe center energetically less accessible. Previous efforts to directly transplant successful strategies from Ru(II)L6 complexes unfortunately met with limited success in this regard, despite their close chemical kinship. In this Account, we summarize recent promising results from our and other groups in utilizing strongly σ-donating N-heterocyclic carbene (NHC) ligands to make strong-field Fe(II)L6 complexes with significantly extended (3)MLCT lifetimes. Already some of the first

  11. No Photon Wasted: An Efficient and Selective Singlet Oxygen Photosensitizing Protein.

    PubMed

    Westberg, Michael; Bregnhøj, Mikkel; Etzerodt, Michael; Ogilby, Peter R

    2017-10-12

    Optogenetics has been, and will continue to be, a boon to mechanistic studies of cellular processes. Genetically encodable proteins that sensitize the production of reactive oxygen species (ROS) are expected to play an increasingly important role, particularly in elucidating mechanisms of temporally and spatially dependent cell signaling. However, a substantial challenge in developing such photosensitizing proteins has been to funnel the optical excitation energy into the initial selective production of only one ROS. Singlet molecular oxygen, O 2 (a 1 Δ g ), is a ROS known to have a wide range of effects on cell function. Nevertheless, mechanistic details of singlet oxygen's behavior in a cell are lacking. On the basis of the rational optimization of a LOV-derived flavoprotein, we now report the development and photophysical characterization of a protein-encased photosensitizer that efficiently and selectively produces singlet oxygen at the expense of other ROS, especially ROS that derive from photoinduced electron transfer reactions. These results set the stage for a plethora of new experiments to elucidate ROS-mediated events in cells.

  12. Selenorhodamine Photosensitizers for Photodynamic Therapy of P-Glycoprotein-Expressing Cancer Cells

    PubMed Central

    2015-01-01

    We examined a series of selenorhodamines with amide and thioamide functionality at the 5-position of a 9-(2-thienyl) substituent on the selenorhodamine core for their potential as photosensitizers for photodynamic therapy (PDT) in P-glycoprotein (P-gp) expressing cells. These compounds were examined for their photophysical properties (absorption, fluorescence, and ability to generate singlet oxygen), for their uptake into Colo-26 cells in the absence or presence of verapamil, for their dark and phototoxicity toward Colo-26 cells, for their rates of transport in monolayers of multidrug-resistant, P-gp-overexpressing MDCKII-MDR1 cells, and for their colocalization with mitochondrial specific agents in Colo-26 cells. Thioamide derivatives 16b and 18b were more effective photosensitizers than amide derivatives 15b and 17b. Selenorhodamine thioamides 16b and 18b were useful in a combination therapy to treat Colo-26 cells in vitro: a synergistic therapeutic effect was observed when Colo-26 cells were exposed to PDT and treatment with the cancer drug doxorubicin. PMID:25250825

  13. Luminescence of Radachlorin Photosensitizer in Aqueous Solution under Excitation at 405 and 660 nm

    NASA Astrophysics Data System (ADS)

    Beltukova, D. M.; Belik, V. P.; Vasyutinskii, O. S.; Gadzhiev, I. M.; Goncharov, S. E.; Semenova, I. V.

    2018-01-01

    Entire luminescence spectrum of a commercial photosensitizer Radachlorin in aqueous solution has been recorded under laser excitation at 660 nm and analyzed. The peak of singlet oxygen phosphorescence at 1274 nm has been observed. The results obtained were compared with those recorded with laser excitation at 405 nm and reported earlier. The comparison showed the similarity of relaxation and luminescence processes occurring in both cases. Effective absorption cross sections were determined at each excitation wavelength, it was also shown that the singlet oxygen quantum yield is independent of photosensitizer concentration. The lifetime of the first excited triplet state in Radachlorin was determined. The results obtained can be used for optimization of the conditions of singlet oxygen generation and detection in solutions and biological samples.

  14. Lifting All Boats? Finance Litigation, Education Resources, and Student Needs in the Post-"Rose" Era

    ERIC Educational Resources Information Center

    Sims, David P.

    2011-01-01

    "Rose v. Council for Better Education" (1989) is often considered a transition point in education finance litigation, heralding an era of increasing concern for measurable adequacy of education across a broad spectrum of student needs. Prior research suggests that post-Rose lawsuits had less effect on the distribution of school spending…

  15. Push-Pull Factors of Undocumented Migration from Bangladesh to West Bengal: A Perception Study

    ERIC Educational Resources Information Center

    Datta, Pranati

    2004-01-01

    Movement is an integral part of human existence. While talking about transborder migration from Bangladesh to India, we are, however, aware that this is a controversial subject. The partition of Bengal in 1947 was the cruelest partition in the history of the world and caused forced illegal migration from erstwhile East Pakistan. It is estimated…

  16. cRGD Peptide-Conjugated Pyropheophorbide-a Photosensitizers for Tumor Targeting in Photodynamic Therapy.

    PubMed

    Li, Wenjing; Tan, Sihai; Xing, Yutong; Liu, Qian; Li, Shuang; Chen, Qingle; Yu, Min; Wang, Fengwei; Hong, Zhangyong

    2018-04-02

    Pyropheophorbide-a (Pyro) is a highly promising photosensitizer for tumor photodynamic therapy (PDT), although its very limited tumor-accumulation ability seriously restricts its clinical applications. A higher accumulation of photosensitizers is very important for the treatment of deeply seated and larger tumors. The conjugation of Pyro with tumor-homing peptide ligands could be a very useful strategy to optimize the physical properties of Pyro. Herein, we reported our studies on the conjugation of Pyro with a cyclic cRGDfK (cRGD) peptide, an integrin binding sequence, to develop highly tumor-specific photosensitizers for PDT application. To further reduce the nonspecific uptake and, thus, reduce the background distribution of the conjugates in normal tissues, we opted to add a highly hydrophilic polyethylene glycol (PEG) chain and an extra strongly hydrophilic carboxylic acid group as the linker to avoid the direct connection of the strongly hydrophobic Pyro macrocycle and cRGD ligand. We reported here the synthesis and characterization of these conjugates, and the influence of the hydrophilic modification on the biological function of the conjugates was carefully studied. The tumor-accumulation ability and photodynamic-induced cell-killing ability of these conjugates were evaluated through both in vitro cell-based experiment and in vivo distribution and tumor therapy experiments with tumor-bearing mice. Thus, the synthesized conjugate significantly improved the tumor enrichment and tumor selectivity of Pyro, as well as abolished the xenograft tumors in the murine model through a one-time PDT treatment.

  17. 78 FR 42153 - Requested Administrative Waiver of the Coastwise Trade Laws: Vessel COMPASS ROSE; Invitation for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-07-15

    ... DEPARTMENT OF TRANSPORTATION Maritime Administration [Docket No. MARAD-2013-0081] Requested Administrative Waiver of the Coastwise Trade Laws: Vessel COMPASS ROSE; Invitation for Public Comments AGENCY... COMPASS ROSE is: Intended Commercial Use Of Vessel: ``Sailboat charters six passengers or less...

  18. Verification of key odorants in rose oil by gas chromatography-olfactometry/aroma extract dilution analysis, odour activity value and aroma recombination.

    PubMed

    Xiao, Zuobing; Li, Jing; Niu, Yunwei; Liu, Qiang; Liu, Junhua

    2017-10-01

    Rose oil is much too expensive but very popular. It's well known that the flower oil's aroma profile hasn't been intensively investigated. In order to verify the aroma profile of rose oil, the synthetic blend of odorants was prepared and then compared with the original rose oil using electronic nose analysis (ENA) combined with quantitative descriptive analysis (QDA). The odorants from rose oils were screened out by Gas Chromatography-Olfactometry/aroma extract dilution analysis (GC-O/AEDA) combined with odour activity value (OAV). Both ENA and QDA indicated the recombination model derived from OAV and GC-O/AEDA closely resembled the original rose oil. The experiment results show that rose oxide, linalool, α-pinene, β-pinene, nonanal, heptanal citronellal, phenyl ethyl alcohol, benzyl alcohol, eugenol, methyl eugenol, β-citronellol, hexyl acetate, β-ionone, nerol, etc. are very important constituent to rose oil aroma profile.

  19. Pentalysine β-Carbonylphthalocyanine Zinc: An Effective Tumor-Targeting Photosensitizer for Photodynamic Therapy

    PubMed Central

    Chen, Zhuo; Zhou, Shanyong; Chen, Jincan; Deng, Yicai; Luo, Zhipu; Chen, Hongwei; Hamblin, Michael R.

    2010-01-01

    Unsymmetrical phthalocyanine derivatives have been widely studied as photosensitizers for photodynamic therapy (PDT), targeting various tumor types. However, the preparation of unsymmetrical phthalocyanines is always a challenge due to the presence of many possible structural isomers. Herein we report a new unsymmetrical zinc phthalocyanine, pentalysine β-carbonylphthalocyanine zinc (ZnPc-(Lys)5), that was prepared in large quantity and high purity. This is a water-soluble cationic photosensitizer and maintains a high quantum yield of singlet oxygen generation similar to that of unsubstituted zinc phthalocyanine (ZnPc). Compared with anionic ZnPc counterparts, ZnPc-(Lys)5 shows a higher level cellular uptake and 20-fold higher phototoxicity toward tumor cells. Pharmacokinetics and PDT studies of ZnPc-(Lys)5 in S180 tumor-bearing mice showed a high ratio of tumor versus skin retention and significant tumor inhibition. This new molecular framework will allow synthetic diversity in the number of lysine residues incorporated and will facilitate future QSAR studies. PMID:20458713

  20. Bay of Bengal Exhibits Warming Trend During the Younger Dryas: Implications of AMOC

    NASA Astrophysics Data System (ADS)

    Panmei, Champoungam; Divakar Naidu, Pothuri; Mohtadi, Mahyar

    2017-12-01

    A sharp decline in temperature during the Younger Dryas (YD) preceding the current warmer Holocene is well documented in climate archives from the Northern Hemisphere high latitudes. Although the magnitude of YD cooling varied spatially, the response of YD cooling was well documented in the Atlantic and Pacific Oceans but not in the Indian Ocean. Here we investigate whether the modern remote forcing of tropical Indian Ocean sea surface temperature (SST) by Northern Hemisphere climate changes holds true for events such as the YD. Our SST reconstruction from the western Bay of Bengal exhibits an overall warming of ˜1.8°C during the YD. We further compared our data with other existing Mg/Ca-based SST records from the Northern Indian Ocean and found no significant negative SST anomalies in both the Arabian Sea and the Bay of Bengal compared to pre- and post-YD, suggesting that no apparent cooling occurred during the YD in the Northern Indian Ocean. In contrast, most part of the YD exhibits positive SST anomalies in the Northern Indian Ocean that coincide with the slowdown of the Atlantic Meridional Overturning Circulation during this period.

  1. Molecular analysis of microbial community in arsenic-rich groundwater of Kolsor, West Bengal.

    PubMed

    Sarkar, Angana; Paul, Dhiraj; Kazy, Sufia K; Sar, Pinaki

    2016-01-01

    Bacterial community composition within the highly arsenic (As) contaminated groundwater from Kolsur, West Bengal was analyzed over a period of 3 years using 16S rRNA gene clone library and Denaturing Gradient Gel Electrophoresis (DGGE). Molecular phylogenetic study revealed abundance of α-Proteobacteria (56%) and Firmicutes (29%) along with members of β-Proteobacteria, Verrucomicrobia and Sphingobacteria as relatively minor groups. Along with consistent physicochemical environment, a stable microbial community structure comprising of bacterial genera Agrobacterium-Rhizobium, Ochrobactrum, Pseudomonas, Anoxybacillus and Penibacillus was recorded over the three years study period. Presence of cytosolic arsenate reductase (arsC) gene was observed within the microbial community. Phylogenetic analyses revealed that all the arsC sequences were closely related to the same gene from γ-proteobacterial members while the community was consisted of mainly α-proteobacterial groups. Such phylogenetic incongruence between 16S rRNA and arsC genes possibly indicated horizontal gene transfer (HGT) of the ars genes within the groundwater community. Overall, the study reported a nearly stable geomicrobial environment and genetic determinant related to As homeostasis gene, and provided a better insight on biogeochemistry of As contaminated aquifer of West Bengal.

  2. Population-based prevention of eating disorders: an application of the Rose prevention model.

    PubMed

    Austin, S B

    2001-03-01

    Several decades of concerted research on eating disorders have generated a broad range of proposed causal influences, but much of this etiologic research does not elucidate practical avenues for preventive interventions. Translating etiologic theory into community health interventions depends on the identification of key leverage points, factors that are amenable to public health intervention and provide an opportunity to maximize impact on the outcome of interest. Population-based preventive strategies, elaborated by epidemiologist Geoffrey Rose, can maximize the impact of public health interventions. In the case of eating disorders, Rose's model is instructive: Dieting stands out as risk behavior that may both fit Rose's model well and be a key leverage point for preventive intervention. Grounded in Rose's work, this article lodges a theoretical argument for the population-based prevention of eating disorders. In the introductory section, existing research on the epidemiology of dieting is reviewed, showing that it is extremely common among adolescent girls and women and that the behavior has been implicated as a causal factor for disordered eating. Next, new evidence is offered to build a case for how a population-wide reduction in dieting may be an effective strategy for prevention of eating pathology. Finally Rose's prevention framework is used to introduce a unique and provocative perspective on the prevention of eating disorders. Dieting is a normative behavior in our culture with psychological and physiological effects in the causal chain leading to eating pathology. This behavior may represent an ideal target for population-based prevention. Theoretical and empirical evidence suggests that a population-wide reduction in dieting may be a justifiable and effective strategy for prevention of eating pathology. Copyright 2001 American Health Foundation and Academic Press.

  3. Rose's population strategy of prevention need not increase social inequalities in health.

    PubMed

    McLaren, Lindsay; McIntyre, Lynn; Kirkpatrick, Sharon

    2010-04-01

    Geoffrey Rose's 1985 paper, Sick individuals and sick populations, continues to spark debate and discussion. Since this original publication, there have been two notable challenges to Rose's population strategy of prevention. First, identification of high-risk individuals has improved considerably in accuracy, which some believe obviates the need for population-wide prevention strategies. Secondly, and more recently, it has been suggested that population strategies of prevention may inadvertently worsen social inequalities in health. We argue that population prevention will not necessarily worsen social inequalities in health, and the likelihood of it doing so will depend on whether the prevention strategy is more structural (targets conditions in which behaviours occur) or agentic (targets behaviour change among individuals) in nature. Also, there are potential drawbacks of approaches that focus on discrete populations (i.e. high risk or vulnerable) that need to be considered when selecting a strategy. Although Rose's ideas need to be continually scrutinized, his population strategy of prevention still holds considerable merit for improving population health and narrowing social inequalities in health.

  4. Photosensitivity enhancement of PLZT ceramics by positive ion implantation

    DOEpatents

    Peercy, P.S.; Land, C.E.

    1980-06-13

    The photosensitivity of lead lanthanum zirconate titanate (PLZT) ceramic material used in high resolution, high contrast, and non-volatile photoferroelectric image storage and display devices is enhanced significantly by positive ion implantation of the PLZT near its surface. Ions that are implanted include H/sup +/, He/sup +/, Ar/sup +/, and a preferred co-implant of Ar/sup +/ and Ne/sup +/. The positive ion implantation advantageously serves to shift the band gap energy threshold of the PLZT material from near-uv light to visible blue light. As a result, photosensitivity enhancement is such that the positive ion implanted PLZT plate is sensitive even to sunlight and conventional room lighting, such as fluorescent and incandescent light sources. The method disclosed includes exposing the PLZT plate to these positive ions of sufficient density and with sufficient energy to provide an image. The PLZT material may have a lanthanum content ranging from 5 to 10%; a lead zirconate content ranging from 62 to 70 mole %; and a lead titanate content ranging from 38 to 30%. The region of ion implantation is in a range from 0.1 to 2 microns below the surface of the PLZT plate. Density of ions is in the range from 1 x 10/sup 12/ to 1 x 10/sup 17/ ions/cm/sup 2/ and having an energy in the range from 100 to 500 keV.

  5. Photosensitive naturally derived resins toward optical 3-D printing

    NASA Astrophysics Data System (ADS)

    Skliutas, Edvinas; Kasetaite, Sigita; Jonušauskas, Linas; Ostrauskaite, Jolita; Malinauskas, Mangirdas

    2018-04-01

    Recent advances in material engineering have shown that renewable raw materials, such as plant oils or glycerol, can be applied for synthesis of polymers due to ready availability, inherent biodegradability, limited toxicity, and existence of modifiable functional groups and eventually resulting to a potentially lower cost. After additional chemical modifications (epoxidation, acrylation, double bonds metathesis, etc.), they can be applied in such high-tech areas as stereolithography, which allows fabrication of three-dimensional (3-D) objects. "Autodesk's" 3-D optical printer "Ember" using 405-nm light was implemented for dynamic projection lithography. It enabled straightforward spatio-selective photopolymerization on demand, which allows development of various photosensitive materials. The bio-based resins' photosensitivity was compared to standard "Autodesk" "PR48" and "Formlabs" "Clear" materials. It turned out that the bioresins need a higher energy dose to be cured (a least 16 J · cm - 2 for a single layer varying from 100 to 130 μm). Despite this, submillimeter range 2.5-D structural features were formed, and their morphology was assessed by optical profilometer and scanning electron microscope. It was revealed that a higher exposition dose (up to 26 J · cm - 2) results in a linear increase in the formed structures height, proving controllability of the undergoing process. Overall, the provided results show that naturally derived resins are suitable candidates for tabletop gray-tone lithography.

  6. RiceCAP: Comparison of sheath blight QTLs in two Bengal/O. nivara advanced backcross mapping populations

    USDA-ARS?s Scientific Manuscript database

    Two advanced backcross populations were developed between a popular southern US tropical japonica rice (Oryza sativa L.) cultivar Bengal and two different of Oryza nivara (IRGC100898; IRGC104705) accessions to identify quantitative trait loci (QTLs) related to sheath blight (SB) disease resistance. ...

  7. 76 FR 25322 - Oklahoma Rose Water LLC; Notice of Preliminary Permit Application Accepted for Filing and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-04

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Project No. 13854-000] Oklahoma Rose Water LLC; Notice of Preliminary Permit Application Accepted for Filing and Soliciting Comments, Motions To Intervene, and Competing Applications On September 30, 2010, Oklahoma Rose Water LLC filed an...

  8. 77 FR 57082 - Prairie Rose Wind, LLC; Supplemental Notice That Initial Market-Based Rate Filing Includes...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-17

    ... DEPARTMENT OF ENERGY Federal Energy Regulatory Commission [Docket No. ER12-2542-000] Prairie Rose Wind, LLC; Supplemental Notice That Initial Market- Based Rate Filing Includes Request for Blanket... Rose Wind, LLC's application for market-based rate authority, with an accompanying rate schedule...

  9. Lethal photosensitization of biofilm-grown bacteria

    NASA Astrophysics Data System (ADS)

    Wilson, Michael

    1997-12-01

    Antibacterial agents are increasingly being used for the prophylaxis and treatment of oral diseases. As these agents can be rendered ineffective by resistance development in the target organisms there is a need to develop alternative antimicrobial approaches. Light-activated antimicrobial agents release singlet oxygen and free radicals which can kill adjacent bacteria and a wide range of cariogenic and periodontopathogenic bacteria has been shown to be susceptible to such agents. In the oral cavity these organisms are present as biofilms (dental plaques) which are less susceptible to traditional antimicrobial agents than bacterial suspensions. The results of these studies have shown that biofilm-grown oral bacteria are also susceptible to lethal photosensitization although the light energy doses required are grater than those needed to kill the organisms when they are grown as aqueous suspensions.

  10. Neuroendocrine Tumor-Targeted Upconversion Nanoparticle-Based Micelles for Simultaneous NIR-Controlled Combination Chemotherapy and Photodynamic Therapy, and Fluorescence Imaging

    PubMed Central

    Chen, Guojun; Jaskula-Sztul, Renata; Esquibel, Corinne R.; Lou, Irene; Zheng, Qifeng; Dammalapati, Ajitha; Harrison, April; Eliceiri, Kevin W.; Tang, Weiping

    2017-01-01

    Although neuroendocrine tumors (NETs) are slow growing, they are frequently metastatic at the time of discovery and no longer amenable to curative surgery, emphasizing the need for the development of other treatments. In this study, multifunctional upconversion nanoparticle (UCNP)-based theranostic micelles are developed for NET-targeted and near-infrared (NIR)-controlled combination chemotherapy and photodynamic therapy (PDT), and bioimaging. The theranostic micelle is formed by individual UCNP functionalized with light-sensitive amphiphilic block copolymers poly(4,5-dimethoxy-2-nitrobenzyl methacrylate)-polyethylene glycol (PNBMA-PEG) and Rose Bengal (RB) photosensitizers. A hydrophobic anticancer drug, AB3, is loaded into the micelles. The NIR-activated UCNPs emit multiple luminescence bands, including UV, 540 nm, and 650 nm. The UV peaks overlap with the absorption peak of photocleavable hydrophobic PNBMA segments, triggering a rapid drug release due to the NIR-induced hydrophobic-to-hydrophilic transition of the micelle core and thus enabling NIR-controlled chemotherapy. RB molecules are activated via luminescence resonance energy transfer to generate 1O2 for NIR-induced PDT. Meanwhile, the 650 nm emission allows for efficient fluorescence imaging. KE108, a true pansomatostatin nonapeptide, as an NET-targeting ligand, drastically increases the tumoral uptake of the micelles. Intravenously injected AB3-loaded UCNP-based micelles conjugated with RB and KE108—enabling NET-targeted combination chemotherapy and PDT—induce the best antitumor efficacy. PMID:28989337

  11. Mechanism of Cyclic Dye Regeneration During Eosin-Sensitized Photoinitiation in the Presence of Polymerization Inhibitors

    PubMed Central

    Avens, Heather J.; Bowman, Christopher N.

    2009-01-01

    A visible light photoinitiator, eosin, in combination with a tertiary amine coinitiator is found to initiate polymerization despite the presence of at least 1000-fold excess dissolved oxygen which functions as an inhibitor of radical polymerizations. Additionally, 0.4 µM eosin is able to overcome 100-fold excess (40 µM) 2,2,6,6-Tetramethyl-1-piperidinyloxy (TEMPO) inhibitor, initiating polymerization after only a 2 minute inhibition period. In contrast, 40 µM Irgacure-2959, a standard cleavage-type initiator, is unable to overcome even an equivalent amount of inhibitor (40 µM TEMPO). Through additional comparisons of these two initiation systems, a reaction mechanism is developed which is consistent with the kinetic data and provides an explanation for eosin’s relative insensitivity to oxygen, TEMPO and other inhibitors. A cyclic mechanism is proposed in which semi-reduced eosin radicals react by disproportionation with radical inhibitors and radical intermediates in the inhibition process to regenerate eosin and effectively consume inhibitor. In behavior similar to that of eosin, rose bengal, fluorescein, and riboflavin are also found to initiate polymerization despite the presence of excess TEMPO, indicating that cyclic regeneration likely enhances the photoinitiation kinetics of many dye photosensitizers. Selection of such dye initiation systems constitutes a valuable strategy for alleviating inhibitory effects in radical polymerizations. PMID:20098667

  12. Neuroendocrine Tumor-Targeted Upconversion Nanoparticle-Based Micelles for Simultaneous NIR-Controlled Combination Chemotherapy and Photodynamic Therapy, and Fluorescence Imaging.

    PubMed

    Chen, Guojun; Jaskula-Sztul, Renata; Esquibel, Corinne R; Lou, Irene; Zheng, Qifeng; Dammalapati, Ajitha; Harrison, April; Eliceiri, Kevin W; Tang, Weiping; Chen, Herbert; Gong, Shaoqin

    2017-02-23

    Although neuroendocrine tumors (NETs) are slow growing, they are frequently metastatic at the time of discovery and no longer amenable to curative surgery, emphasizing the need for the development of other treatments. In this study, multifunctional upconversion nanoparticle (UCNP)-based theranostic micelles are developed for NET-targeted and near-infrared (NIR)-controlled combination chemotherapy and photodynamic therapy (PDT), and bioimaging. The theranostic micelle is formed by individual UCNP functionalized with light-sensitive amphiphilic block copolymers poly(4,5-dimethoxy-2-nitrobenzyl methacrylate)-polyethylene glycol (PNBMA-PEG) and Rose Bengal (RB) photosensitizers. A hydrophobic anticancer drug, AB3, is loaded into the micelles. The NIR-activated UCNPs emit multiple luminescence bands, including UV, 540 nm, and 650 nm. The UV peaks overlap with the absorption peak of photocleavable hydrophobic PNBMA segments, triggering a rapid drug release due to the NIR-induced hydrophobic-to-hydrophilic transition of the micelle core and thus enabling NIR-controlled chemotherapy. RB molecules are activated via luminescence resonance energy transfer to generate 1 O 2 for NIR-induced PDT. Meanwhile, the 650 nm emission allows for efficient fluorescence imaging. KE108, a true pansomatostatin nonapeptide, as an NET-targeting ligand, drastically increases the tumoral uptake of the micelles. Intravenously injected AB3-loaded UCNP-based micelles conjugated with RB and KE108-enabling NET-targeted combination chemotherapy and PDT-induce the best antitumor efficacy.

  13. Geologic framework and hydrogeologic characteristics of the Glen Rose limestone, Camp Stanley Storage Activity, Bexar County, Texas

    USGS Publications Warehouse

    Clark, Allan K.

    2004-01-01

    The Trinity aquifer is a regional water source in the Hill Country of south-central Texas that supplies water for agriculture, commercial, domestic, and stock purposes. Rocks of the Glen Rose Limestone, which compose the upper zone and upper part of the middle zone of the Trinity aquifer, crop out at the Camp Stanley Storage Activity (CSSA), a U.S. Army weapons and munitions supply, maintenance, and storage facility in northern Bexar County (San Antonio area) (fig. 1). On its northeastern, eastern, and southern boundaries, the CSSA abuts the Camp Bullis Training Site, a U.S. Army field training site for military and Federal government agencies. During 2003, the U.S. Geological Survey (USGS), in cooperation with the U.S. Army, studied the outcropping Glen Rose Limestone at the CSSA and immediately adjacent area (Camp Stanley study area, fig. 1) to identify and map the hydrogeologic subdivisions and faults of the Glen Rose Limestone at the facility. The results of the study are intended to help resource managers improve their understanding of the distribution of porosity and permeability of the outcropping rocks, and thus the conditions for recharge and the potential for contaminants to enter the Glen Rose Limestone. This study followed a similar study done by the USGS at Camp Bullis (Clark, 2003). The purpose of this report is to present the geologic framework and hydrogeologic characteristics of the Glen Rose Limestone in the study area. The hydrogeologic nomenclature follows that introduced by Clark (2003) for the outcropping Glen Rose Limestone at Camp Bullis in which the upper member of the Glen Rose Limestone (hereinafter, upper Glen Rose Limestone), which is coincident with the upper zone of the Trinity aquifer, is divided into five intervals on the basis of observed lithologic and hydrogeologic properties. An outcrop map, two generalized sections, related illustrations, and a table summarize the description of the framework and distribution of characteristics.

  14. Localisation and origin of the bacteriochlorophyll-derived photosensitizer in the retina of the deep-sea dragon fish Malacosteus niger

    PubMed Central

    Douglas, Ronald H.; Genner, Martin J.; Hudson, Alan G.; Partridge, Julian C.; Wagner, Hans-Joachim

    2016-01-01

    Most deep-sea fish have a single visual pigment maximally sensitive at short wavelengths, approximately matching the spectrum of both downwelling sunlight and bioluminescence. However, Malcosteus niger produces far-red bioluminescence and its longwave retinal sensitivity is enhanced by red-shifted visual pigments, a longwave reflecting tapetum and, uniquely, a bacteriochlorophyll-derived photosensitizer. The origin of the photosensitizer, however, remains unclear. We investigated whether the bacteriochlorophyll was produced by endosymbiotic bacteria within unusual structures adjacent to the photoreceptors that had previously been described in this species. However, microscopy, elemental analysis and SYTOX green staining provided no evidence for such localised retinal bacteria, instead the photosensitizer was shown to be distributed throughout the retina. Furthermore, comparison of mRNA from the retina of Malacosteus to that of the closely related Pachystomias microdon (which does not contain a bacterichlorophyll-derived photosensitzer) revealed no genes of bacterial origin that were specifically up-regulated in Malacosteus. Instead up-regulated Malacosteus genes were associated with photosensitivity and may relate to its unique visual ecology and the chlorophyll-based visual system. We also suggest that the unusual longwave-reflecting, astaxanthin-based, tapetum of Malacosteus may protect the retina from the potential cytotoxicity of such a system. PMID:27996027

  15. Experimental photodynamic laser therapy for rheumatoid arthritis with a second generation photosensitizer.

    PubMed

    Hendrich, C; Hüttmann, G; Vispo-Seara, J L; Houserek, S; Siebert, W E

    2000-01-01

    Photodynamic laser therapy has been shown to be a new method for the treatment of synovitis in various animal models. Its principle is the accumulation of a photosensitizing drug in the inflamed synovium which is destroyed by photoactivation of the drug. In the present animal study we demonstrate the effect of a second-generation photosensitizer and suggest a concept for light dosimetry within the joint. We used 38 inbred rabbits for the IgG-induced arthritis model; 2 mg/kg of the benzoporphyrin derivative monoacid ring-A (BPD-MA) Verteporfin were administered 3 h before irradiation, which was performed using a 690-nm diode laser coupled to quartz glass fiber with a cylinder diffusor tip at a total light energy of either 180 or 470 J. During irradiation specific fluorescence of BPD-MA was monitored using a spectroscopy unit. The effect of the photodynamic laser therapy was documented grossly and histologically after 1 week. Within the 470 J-group a complete necrosis of the inflamed synovium was observed. The bradytrophic structures of the joint, however, remained unchanged. Throughout the 180 J-group the extent of necrosis was minor. During irradiation the tissue fluorescence of BPD-MA showed a dose-dependent decrease. Using BPD-MA as a photosensitizer a highly selective and minimal invasive synoviorthesis can be performed. At a dose of 2 mg/kg the histological effect depends on the light dose. For optimum efficacy a total energy of 470 J seems favorable. Online fluorescence detection can be used to monitor the effect of light administration. For dosimetry therefore an online tissue fluorescence detection may represent a technical solution.

  16. Application of individual foraminifera Mg/Ca and δ18O analyses for paleoceanographic reconstructions in the Bay of Bengal and other active depositional environments

    NASA Astrophysics Data System (ADS)

    Fritz-Endres, T.; Dekens, P.; Fehrenbacher, J. S.; Spero, H. J.; Stine, A.

    2017-12-01

    Paleoceanographic research traditionally focuses on regions where sediment deposition is minimally affected by transport. However, sediment fans near tectonically active regions provide an opportunity to link oceanographic climate to terrestrial processes. Sediment cores recovered during IODP Expedition 354 in the Bay of Bengal include hemipelagic sections that record the history of tectonic uplift and the development of the Indian Monsoon through the last 10 Ma. Although these cores provide a unique opportunity to link marine and terrestrial climate, the complex depositional environment requires that the source of foraminifera is carefully considered before using these proxies to reconstruct oceanographic conditions. Foraminifera in Bengal Fan sediments may have been transported via turbidity currents from the northern Bay of Bengal, where the seasonal variability of SST and SSS is larger compared to the southern Bay of Bengal. We measured single Globigerinoides sacculifer Mg/Ca and δ18O from mudline samples of IODP Site U1454 (8.4°N, 85.5°E, 3721 m water depth) near the modern active channel and Site U1449 (8.4°N, 88.7°E, 3653 m water depth) far from channel activity. We compare these sites to single G. sacculifer from the core-top sample of Site 342KL (20.6°N, 90.1°E, 1256 m water depth) located on the continental shelf. Each foraminifera lives 2-4 weeks and the distribution of 60 to 80 data points reflects the seasonal range of SST and SSS at the location where the foraminifera calcified. Measurements in foraminifera from Site U1449 (away from active channel) are statistically different from the site in the northern Bay of Bengal and more consistent with local conditions. Conversely, foraminifera from the site near the active channel reflect a combined signal of local conditions recorded from the site far from channel activity and those recorded from the continental shelf. This suggests a portion of foraminifera from the active channel site have been

  17. Organic Aerosol Formation Photoenhanced by the Formation of Secondary Photo-sensitizers in ageing Aerosols

    NASA Astrophysics Data System (ADS)

    Aregahegn, Kifle; Nozière, Barbara; George, Christian

    2013-04-01

    Humankind is facing a changing environment possibly due to anthropogenic stress on the atmosphere. In this context, aerosols play a key role by affecting the radiative climate forcing, hydrological cycle, and by their adverse effect on health. The role of organic compounds in these processes is however still poorly understood because of their massive chemical complexity and numerous transformations. This is particularly true for Secondary Organic Aerosol (SOA), which are produced in the atmosphere by organic gases. Traditionally, the driving forces for SOA growth is believed to be the partitioning onto aerosol seeds of condensable gases, either emitted primarily or resulting from the gas phase oxidation of organic gases. However, even the most up-to-date models based on such mechanisms can not account for the SOA mass observed in the atmosphere, suggesting the existence of other, yet unknown formation processes. The present study shows experimental evidence that particulate phase chemistry produces photo-sensitizers that lead to photo-induced formation and growth of secondary organic aerosol in the near UV and the presence of volatile organic compounds (VOC) such as terpenes. By means of an aerosol flow tube reactor equipped with Scanning Mobility Particle Sizer (SMPS) having Kr-85 source aerosol neutralizer, Differential Mobility Analyser (DMA) and Condensation Particle Sizer (CPC), we identified that traces of the aerosol phase product of glyoxal chemistry as is explained in Gallway et al., and Yu et al., namely imidazole-2-carboxaldehyde (IC) is a strong photo-sensitizer when irradiated by near-UV in the presence of volatile organic compounds such as terpenes. Furthermore, the influence of pH, type and concentration of VOCs, composition of seed particles, relative humidity and irradiation intensity on particle growth were studied. This novel photo-sensitizer contributed to more than 30% of SOA growth in 19min irradiation time in the presence of terpenes in the

  18. Photochemical predictive analysis of photodynamic therapy with non-homogeneous topical photosensitizer distribution in dermatological applications

    NASA Astrophysics Data System (ADS)

    Salas-García, I.; Fanjul-Vélez, F.; Ortega-Quijano, N.; López-Escobar, M.; Arce-Diego, J. L.

    2010-04-01

    Photodynamic Therapy (PDT) is a therapeutic technique widely used in dermatology to treat several skin pathologies. It is based in topical or systemic delivery of photosensitizing drugs followed by irradiation with visible light. The subsequent photochemical reactions generate reactive oxygen species which are considered the principal cytotoxic agents to induce cell necrosis. In this work we present a PDT model that tries to predict the photodynamic effect on the skin with a topically administered photosensitizer. The time dependent inhomogeneous distribution of the photoactive compound protoporphyrin IX (PpIX) is calculated after obtaining its precursor distribution (Methyl aminolevulinate, MAL) which depends on the drug permeability, diffusion properties of the skin, incubation time and conversion efficiency of MAL to PpIX. Once the optical energy is obtained by means of the Beer Lambert law, a photochemical model is employed to estimate the concentration of the different molecular compounds taking into account the electronic transitions between molecular levels and particles concentrations. The results obtained allow us to know the evolution of the cytotoxic agent in order to estimate the necrotic area adjusting parameters such as the optical power, the photosensitizer concentration, the incubation and exposition time or the diffusivity and permeability of the tissue.

  19. A Nanosystem Capable of Releasing a Photosensitizer Bioprecursor under Two‐Photon Irradiation for Photodynamic Therapy

    PubMed Central

    Wu, Hao; Zeng, Fang; Zhang, Hang; Xu, Jiangsheng

    2015-01-01

    The applications of photodynamic therapy (PDT) are usually limited by photosensitizers' side effects and singlet oxygen's short half‐life. Herein, a mitochondria‐targeted nanosystem is demonstrated to enhance the PDT efficacy by releasing a bio‐precursor of photosensitizer under two‐photon irradiation. A phototriggerable coumarin derivative is first synthesized by linking 5‐aminolevulinic acid (5‐ALA, the bio‐precursor) to coumarin; and the nanosystem (CD‐ALA‐TPP) is then fabricated by covalently incorporating this coumarin derivative and a mitochondria‐targeting compound triphenylphosphonium (TPP) onto carbon dots (CDs). Upon cellular internalization, the nanosystem preferentially accumulates in mitochondria; and under one‐ or two‐photon irradiation, it releases 5‐ALA molecules that are then metabolized into protoporphyrin IX in mitochondria through a series of biosynthesis processes. The subsequent red light irradiation induces this endogenously synthesized photosensitizer to generate singlet oxygen, thereby causing oxidant damage to mitochondria and then the apoptosis of the cells. Analysis via 3‐(4,5‐dimethyl‐2‐thiazolyl)‐2,5‐diphenyltetrazolium bromide (MTT) assays indicate that the novel PDT system exhibits enhanced cytotoxicity toward cancer cells. This study may offer a new strategy for designing PDT systems with high efficacy and low side effects. PMID:27774388

  20. Applicability of new degradable hypericin-polymer-conjugates as photosensitizers: principal mode of action demonstrated by in vitro models.

    PubMed

    Feinweber, Daniela; Verwanger, Thomas; Brüggemann, Oliver; Teasdale, Ian; Krammer, Barbara

    2014-11-01

    Two series of water soluble novel conjugates of the photosensitizer hypericin were prepared and evaluated for their use as agents for photodynamic therapy, with covalently and non-covalently loaded hypericin on functionalised, hydrolytically degradable inorganic-organic hybrid polyphosphazenes. The conjugates showed excellent aqueous solubility and similar fluorescence spectra to pristine hypericin. Detailed in vitro investigations revealed that the substances were non-toxic in the dark over a wide concentration range, but displayed phototoxicity upon irradiation. Cell uptake studies showed rapid uptake with localization of hypericin observed in endoplasmic reticulum, Golgi complex and particularly in the lysosomes. Furthermore, a DNA fragmentation assay revealed that the photosensitizer conjugates are efficient inducers of apoptosis with some tumor cell selectivity caused by faster and enhanced accumulation in A431 than in HaCaT cells, and thus a moderately higher phototoxicity of A431 compared to HaCaT cells. These novel photosensitizer conjugates hence represent viable hydrolytically degradable alternatives for the advanced delivery of hypericin.

  1. Imaging a photodynamic therapy photosensitizer in vivo with a time-gated fluorescence tomography system

    NASA Astrophysics Data System (ADS)

    Mo, Weirong; Rohrbach, Daniel; Sunar, Ulas

    2012-07-01

    We report the tomographic imaging of a photodynamic therapy (PDT) photosensitizer, 2-(1-hexyloxyethyl)-2-devinyl pyropheophorbide-a (HPPH) in vivo with time-domain fluorescence diffuse optical tomography (TD-FDOT). Simultaneous reconstruction of fluorescence yield and lifetime of HPPH was performed before and after PDT. The methodology was validated in phantom experiments, and depth-resolved in vivo imaging was achieved through simultaneous three-dimensional (3-D) mappings of fluorescence yield and lifetime contrasts. The tomographic images of a human head-and-neck xenograft in a mouse confirmed the preferential uptake and retention of HPPH by the tumor 24-h post-injection. HPPH-mediated PDT induced significant changes in fluorescence yield and lifetime. This pilot study demonstrates that TD-FDOT may be a good imaging modality for assessing photosensitizer distributions in deep tissue during PDT monitoring.

  2. 77 FR 35745 - Requested Administrative Waiver of the Coastwise Trade Laws: Vessel SMOKE AND ROSES; Invitation...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-14

    ... DEPARTMENT OF TRANSPORTATION Maritime Administration [Docket No. MARAD 2012 0068] Requested Administrative Waiver of the Coastwise Trade Laws: Vessel SMOKE AND ROSES; Invitation for Public Comments AGENCY... SMOKE AND ROSES is: INTENDED COMMERCIAL USE OF VESSEL: ``We intend to carry up to 10 passengers for hire...

  3. Sunlight exposure behaviour and vitamin D status in photosensitive patients: longitudinal comparative study with healthy individuals at U.K. latitude.

    PubMed

    Rhodes, L E; Webb, A R; Berry, J L; Felton, S J; Marjanovic, E J; Wilkinson, J D; Vail, A; Kift, R

    2014-12-01

    Low vitamin D status is prevalent in wintertime in populations at northerly latitudes. Photosensitive patients are advised to practise sun avoidance, but their sunlight exposure levels, photoprotective measures and resulting vitamin D status are unknown. To examine seasonal vitamin D status in photosensitive patients relative to healthy individuals and to assess quantitatively behavioural and demographic contributors. This was a longitudinal prospective cohort study (53·5°N) examining year-round 25-hydroxyvitamin D [25(OH)D] levels, sun-exposure behaviour and oral vitamin D intake in photosensitive patients diagnosed at a photoinvestigation unit (n = 53), compared with concurrently assessed healthy adults (n = 109). Photosensitive patients achieved seasonal 25(OH)D variation, but insufficient (< 20 ng mL(-1); 50 nmol L(-1)) and even deficient (< 10 ng mL(-1); 25 nmol L(-1)) levels occurred at the summer peak in 47% and 9% of patients, respectively, rising to 73% and 32% at the winter trough. Adjusting for demographic factors, the mean values were lower than for healthy volunteers by 18% [95% confidence interval (CI) 4-29] in summer (P = 0·02) and 25% (95% CI 7-39) in winter (P = 0·01). Behavioural factors explained 25(OH)D differences between cohorts. Patients demonstrated lower weekend ultraviolet B doses (P < 0·001), smaller skin surface area exposure (P = 0·004) and greater sunscreen use (P < 0·001), while average oral vitamin D intake was low in both groups (photosensitive: 2·94 μg per day). Supplementation and summer surface area exposure predicted summer peak and winter trough 25(OH)D levels. A 1 μg per day increment in supplementary vitamin D raised summer and winter 25(OH)D by 5% (95% CI 3-7) and 9% (95% CI 5-12), respectively (both P < 0·001). Photosensitive patients are, through their photoprotective measures, at high risk of year-round low vitamin D status. Guidance on oral measures should target this patient group and their physicians.

  4. The Fowler-Nordheim behavior and mechanism of photo-sensitive field from SnS{sub 2} nanosheets

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Suryawanshi, Sachin R.; Chaudhari, Nilima S.; Warule, Sambhaji S.

    2015-06-24

    Here in, we report photo-sensitive field emission measurements of SnS{sub 2} nanosheets at base pressure of ∼1×10{sup −8} mbar are reported. The nonlinear Fowler-Nordheim (F-N) plot is elucidate according to a (F-N) model of calculation based on shift in a saturation of conduction band current density after light illumination and prevalence of valence band current density at high electric field values. The model of calculation suggests that the slope variation before and after visible light illumination of the F-N plot, in the high-field and low-field regions, does not depend on the magnitude of saturation but also depend on charge carriermore » (electron) concentration get increased in conduction band. The F-N model of calculation is important for the fundamental understanding of the photo-sensitive field emission mechanism of semiconducting SnS{sub 2}. The replicate F-N plots exhibit similar features to those observed experimentally. The model calculation suggests that the nonlinearity of the F-N plot is a characteristic of the photo-enhanced energy band structure of the photo-sensitive semiconductor material.« less

  5. Highly reliable photosensitive organic-inorganic hybrid passivation layers for a-InGaZnO thin-film transistors

    NASA Astrophysics Data System (ADS)

    Bermundo, Juan Paolo; Ishikawa, Yasuaki; Yamazaki, Haruka; Nonaka, Toshiaki; Fujii, Mami N.; Uraoka, Yukiharu

    2015-07-01

    We report the fabrication of a photosensitive hybrid passivation material on amorphous InGaZnO (a-IGZO) thin-film transistors (TFTs) that greatly enhance its stability and improve its electrical characteristics. The hybrid passivation based on polysilsesquioxane is transparent and fabricated using a simple solution process. Because the passivation is photosensitive, dry etching was never performed during TFT fabrication. TFTs passivated with this material had a small threshold voltage shift of 0.5 V during positive bias stress, 0.5 V during negative bias stress, and -2.5 V during negative bias illumination stress. Furthermore, TFTs passivated by this layer were stable after being subjected to high relative humidity stress — confirming the superb barrier ability of the passivation. Analysis of secondary ion mass spectrometry showed that a large amount of hydrogen, carbon, and fluorine can be found in the channel region. We show that both hydrogen and fluorine reduced oxygen vacancies and that fluorine stabilized weak oxygen and hydroxide bonds. These results demonstrate the large potential of photosensitive hybrid passivation layers as effective passivation materials.

  6. Platelet-activating factor receptor agonists mediate xeroderma pigmentosum A photosensitivity.

    PubMed

    Yao, Yongxue; Harrison, Kathleen A; Al-Hassani, Mohammed; Murphy, Robert C; Rezania, Samin; Konger, Raymond L; Travers, Jeffrey B

    2012-03-16

    To date, oxidized glycerophosphocholines (Ox-GPCs) with platelet-activating factor (PAF) activity produced non-enzymatically have not been definitively demonstrated to mediate any known disease processes. Here we provide evidence that these Ox-GPCs play a pivotal role in the photosensitivity associated with the deficiency of the DNA repair protein xeroderma pigmentosum type A (XPA). It should be noted that XPA-deficient cells are known to have decreased antioxidant defenses. These studies demonstrate that treatment of human XPA-deficient fibroblasts with the pro-oxidative stressor ultraviolet B (UVB) radiation resulted in increased reactive oxygen species and PAF receptor (PAF-R) agonistic activity in comparison with gene-corrected cells. The UVB irradiation-generated PAF-R agonists were inhibited by antioxidants. UVB irradiation of XPA-deficient (Xpa-/-) mice also resulted in increased PAF-R agonistic activity and skin inflammation in comparison with control mice. The increased UVB irradiation-mediated skin inflammation and TNF-α production in Xpa-/- mice were blocked by systemic antioxidants and by PAF-R antagonists. Structural characterization of PAF-R-stimulating activity in UVB-irradiated XPA-deficient fibroblasts using mass spectrometry revealed increased levels of sn-2 short-chain Ox-GPCs along with native PAF. These studies support a critical role for PAF-R agonistic Ox-GPCs in the pathophysiology of XPA photosensitivity.

  7. The Tsunami Geology of the Bay of Bengal Shores and the Predecessors of the 2004 Indian Ocean Event

    NASA Astrophysics Data System (ADS)

    Rajendran, C.; Rajendran, K.; Seshachalam, S.; Andrade, V.

    2010-12-01

    The 2004 Aceh-Andaman earthquake exceeded the known Indian Ocean precedents by its 1,300-km long fault rupture and the height and reach of its tsunami. Literature of the ancient Chola dynasty (AD 9-11 centuries) of south India and the archeological excavations allude to a sea flood that crippled the historic port at Kaveripattinam, a trading hub for Southeast Asia. Here, we combine a variety of data from the rupture zone as well as the distant shores to build a tsunami history of the Bay of Bengal. A compelling set of geological proxies of possible tsunami inundation include boulder beds of Car Nicobar Island in the south and the East Island in the northernmost Andaman, a subsided fossil mangrove forest near Port Blair and a washover sedimentation identified in the Kaveripattinam coast of Tamil Nadu, south India. We have developed an extensive chronology for these geological proxies, and we analyze them in conjunction with the historical information culled from different sources for major sea surges along the Bay of Bengal shores. The age data and the depositional characteristics of these geological proxies suggest four major tsunamis in the last 2000 years in the Bay of Bengal, including the 1881 Car Nicobar tsunami. Among these, the evidence for the event of 800-1200 cal yr BP is fairly well represented on both sides of the Bay of Bengal shores. Thus, we surmise that the 800-1000-year old tsunami mimics the transoceanic reach of the 2004 Indian Ocean and the age constraints also agree with the sea surge during the Chola period. We also obtained clues for a possible medieval tsunami from the islands occurred probably a few hundred years after the Chola tsunami, but its size cannot constrained, nor its source. The convergence of ages and the multiplicity of sites would suggest at least one full size predecessor of the 2004 event 1000-800 years ago.

  8. Obstetric care practice in Birbhum District, West Bengal, India.

    PubMed

    Bharati, Susmita; Pal, Manoranjan; Bharati, Premananda

    2007-08-01

    The study area is the Birbhum district of the State of West Bengal in India. It is one of the backward districts in India. The paper investigates the existing pattern of obstetric health care practices and the factors associated with the utilization of such care. The present analysis includes 495 adult married women of both rural and urban areas of nine Blocks of Birbhum district. Besides performing chi2 tests to see the association of the relevant individual and household characteristics, logistic regression was also carried out to measure the effect of these characteristics on the use of obstetric health care. In Birbhum district of West Bengal 65 percent mothers go to doctors for antenatal check-up during their pregnancy, but only 26 percent mothers deliver their babies in institutions and 30 percent mothers get the help of professional health assistants during delivery. Educated women have emphasized role in the practice of obstetric health care. Husband's education and the standard of living of the family also have some effect on the practice of antenatal check up, place of delivery and assistance of health professional. While most of the family background variables have significant effect on the practice of antenatal check up, these variables do not have much effect on the choice of delivery or seeking assistance of health professionals. Contrary to the popular belief the working status of women does not have favourable influence on the obstetric health care practices. In developing countries like India, it is the poverty, which compels the women to take jobs-that too in low paid jobs especially in rural backward areas. The status of literacy of mothers and standard of living of the family are of prime importance in improving the obstetric health care practices.

  9. 2,4,5-Trichlorophenoxyacetic acid promotes somatic embryogenesis in the rose cultivar "Livin' Easy" (Rosa sp.).

    PubMed

    Estabrooks, Tammy; Browne, Robin; Dong, Zhongmin

    2007-02-01

    Somatic embryogenesis (SE) offers vast potential for the clonal propagation of high-value roses. However, some recalcitrant cultivars unresponsive to commonly employed SE-inducing agents and low induction rates currently hinder the commercialization of SE technology in rose. Rose SE technology requires improvement before it can be implemented as a production system on a commercial scale. In the present work, we assessed 2,4,5-trichlorophenoxyacetic acid (2,4,5-T), a synthetic auxin not previously tested in rose, for its effectiveness to induce SE in the rose cultivar "Livin' Easy" (Rosa sp.). We ran a parallel comparison to the commonly used 2,4-dichlorophenoxyacetic acid (2,4-D). We tested each auxin with two different basal media: Murashige and Skoog (MS) basal medium and woody plant medium (WPM). MS medium resulted in somatic embryo production, whereas WPM did not. 2,4,5-T induced SE over a greater concentration range than 2,4-D's and resulted in significantly greater embryo yields. 2,4,5-T at a concentration of 10 or 25 microM was better for embrygenic tissue initiation than 2,4,5-T at 5 microM. Further embryo development occurred when the tissue was transferred to plant growth regulator (PGR) free medium or media with 40% the original auxin concentration. However, the PGR-free medium resulted in a high percentage of abnormal embryos (32.31%) compared to the media containing auxins. Upon transfer to germination medium, somatic embryos successfully converted into plantlets at rates ranging from 33.3 to 95.2%, depending on treatment. Survival rates 3 months ex vitro averaged 14.0 and 55.6% for 2,4-D- and 2,4,5-T-derived plantlets, respectively. Recurrent SE was observed in 60.2% of the plantlets growing on germination medium. This study is the first report of SE in the commercially valuable rose cultivar 'Livin' Easy' (Rosa sp.) and a suitable methodology was developed for SE of this rose cultivar.

  10. Coexistence of wave propagation and oscillation in the photosensitive Belousov-Zhabotinsky reaction on a circular route.

    PubMed

    Nakata, Satoshi; Morishima, Sayaka; Ichino, Takatoshi; Kitahata, Hiroyuki

    2006-12-21

    The photosensitive Belousov-Zhabotinsky (BZ) reaction was investigated on a circular ring, which was drawn using computer software and then projected on a film soaked with BZ solution using a liquid-crystal projector. Under the initial conditions, a chemical wave propagated with a constant velocity on the black ring under a bright background. When the background was rapidly changed to dark, coexistence of the oscillation on part of the ring and propagation of the chemical wave on the other part was observed. These experimental results are discussed in relation to the nature of the photosensitive BZ reaction and theoretically reproduced based on a reaction-diffusion system using the modified Oregonator model.

  11. Resurrecting the Feminine in "The Name of the Rose."

    ERIC Educational Resources Information Center

    Frentz, Thomas S.

    1988-01-01

    Examines how the repressed feminine principle affects the four major discourses in Umberto Eco's "The Name of the Rose." Discusses the historical relationship between the masculine and the feminine in language and religion. Uses that historical frame to guide a close textual analysis of dialectical interplay between the masculine and the…

  12. Putting ROSE to Work: A Proposed Application of a Request-Oriented Scheduling Engine for Space Station Operations

    NASA Technical Reports Server (NTRS)

    Jaap, John; Muery, Kim

    2000-01-01

    Scheduling engines are found at the core of software systems that plan and schedule activities and resources. A Request-Oriented Scheduling Engine (ROSE) is one that processes a single request (adding a task to a timeline) and then waits for another request. For the International Space Station, a robust ROSE-based system would support multiple, simultaneous users, each formulating requests (defining scheduling requirements), submitting these requests via the internet to a single scheduling engine operating on a single timeline, and immediately viewing the resulting timeline. ROSE is significantly different from the engine currently used to schedule Space Station operations. The current engine supports essentially one person at a time, with a pre-defined set of requirements from many payloads, working in either a "batch" scheduling mode or an interactive/manual scheduling mode. A planning and scheduling process that takes advantage of the features of ROSE could produce greater customer satisfaction at reduced cost and reduced flow time. This paper describes a possible ROSE-based scheduling process and identifies the additional software component required to support it. Resulting changes to the management and control of the process are also discussed.

  13. Rose oil (from Rosa × damascena Mill.) vapor attenuates depression-induced oxidative toxicity in rat brain.

    PubMed

    Nazıroğlu, Mustafa; Kozlu, Süleyman; Yorgancıgil, Emre; Uğuz, Abdülhadi Cihangir; Karakuş, Kadir

    2013-01-01

    Oxidative stress is a critical route of damage in various physiological stress-induced disorders, including depression. Rose oil may be a useful treatment for depression because it contains flavonoids which include free radical antioxidant compounds such as rutin and quercetin. We investigated the effects of absolute rose oil (from Rosa × damascena Mill.) and experimental depression on lipid peroxidation and antioxidant levels in the cerebral cortex of rats. Thirty-two male rats were randomly divided into four groups. The first group was used as control, while depression was induced in the second group using chronic mild stress (CMS). Oral (1.5 ml/kg) and vapor (0.15 ml/kg) rose oil were given for 28 days to CMS depression-induced rats, constituting the third and fourth groups, respectively. The sucrose preference test was used weekly to identify depression-like phenotypes during the experiment. At the end of the experiment, cerebral cortex samples were taken from all groups. The lipid peroxidation levels in the cerebral cortex in the CMS group were higher than in control whereas their levels were decreased by rose oil vapor exposure. The vitamin A, vitamin E, vitamin C and β-carotene concentrations in the cerebral cortex were lower in the CMS group than in the control group whereas their concentrations were higher in the rose oil vapor plus CMS group. The CMS-induced antioxidant vitamin changes were not modulated by oral treatment. Glutathione peroxidase activity and reduced glutathione did not change statistically in the four groups following CMS or either treatment. In conclusion, experimental depression is associated with elevated oxidative stress while treatment with rose oil vapor induced protective effects on oxidative stress in depression.

  14. Low-density lipoprotein reconstituted by pyropheophorbide cholesteryl oleate as target-specific photosensitizer.

    PubMed

    Zheng, Gang; Li, Hui; Zhang, Min; Lund-Katz, Sissel; Chance, Britton; Glickson, Jerry D

    2002-01-01

    To target tumors overexpressing low-density lipoprotein receptors (LDLr), a pyropheophorbide cholesterol oleate conjugate was synthesized and successfully reconstituted into the low-density lipoprotein (LDL) lipid core. Laser scanning confocal microscopy studies demonstrated that this photosensitizer-reconstituted LDL can be internalized via LDLr by human hepatoblastoma G(2) (HepG(2)) tumor cells.

  15. Comparisons between data assimilated HYCOM output and in situ Argo measurements in the Bay of Bengal

    NASA Astrophysics Data System (ADS)

    Wilson, E. A.; Riser, S.

    2014-12-01

    This study evaluates the performance of data assimilated Hybrid Coordinate Ocean Model (HYCOM) output for the Bay of Bengal from September 2008 through July 2013. We find that while HYCOM assimilates Argo data, the model still suffers from significant temperature and salinity biases in this region. These biases are most severe in the northern Bay of Bengal, where the model tends to be too saline near the surface and too fresh at depth. The maximum magnitude of these biases is approximately 0.6 PSS. We also find that the model's salinity biases have a distinct seasonal cycle. The most problematic periods are the months following the summer monsoon (Oct-Jan). HYCOM's near surface temperature estimates compare more favorably with Argo, but significant errors exist at deeper levels. We argue that optimal interpolation will tend to induce positive salinity biases in the northern regions of the Bay. Further, we speculate that these biases are introduced when the model relaxes to climatology and assimilates real-time data.

  16. 25. PARK AND ROSE GARDEN ALONG SOUTH SIDE OF F ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    25. PARK AND ROSE GARDEN ALONG SOUTH SIDE OF F STREET, FROM HALFWAY BETWEEN 3RD AND 4TH STREETS, LOOKING WEST. COMMANDING OFFICER'S RESIDENCES AT FAR RIGHT. - Oakland Naval Supply Center, Maritime Street at Seventh Street, Oakland, Alameda County, CA

  17. Sedimentology and arsenic pollution in the Bengal Basin: insight into arsenic occurrence and subsurface geology.

    NASA Astrophysics Data System (ADS)

    Hills, Andrew; McArthur, John

    2014-05-01

    The Bengal delta system is a geologically recent feature overlying a deeply incised palaeo-surface formed during the Last Glacial Maximum. This surface is a series of terraces and valleys created by river incision (Goodbred & Kuehl 2003). The terraces were weathered, forming a thin, indurated laterite deposit (Goodbred & Kuehl 2000) at depths greater than 50 m. McArthur et al. (2008) define this as a palaeosol and have identified it at depths greater than 30 m though out Bangladesh and West Bengal. It has been observed that arsenic concentrations at these sites are lower than the rest of the delta. It has been assumed that the surface morphology at sites where there is a palaeosol are similar and can therefore be characterised by remote sensing, in the form of Google Earth images. Sites were selected in Bangladesh and West Bengal, from work by McArthur et al. (2011); Hoque et al. (2012), where groundwater chemistry and sedimentology data are available making it possible to determine if the subsurface is a palaeo-channel or palaeo-interfluve. Arsenic concentration data have been inputted into Google Earth and the palaeo-channels marked where the arsenic concentration is greater than 10 µg/L, and palaeo-interfluves where arsenic concentration is less than 10 µg/L. The surface morphologies in these domains have been examined for similarities, and it was shown that avulsion scars and abandoned river channels are found where arsenic concentrations are greater than 10 µg/L. Conversely the surrounding areas that are devoid of channel scars have arsenic concentrations less than 10 µg/L. Using the correlation between avulsion features being representative of palaeo-channels and high arsenic concentrations, sites were selected that had a similar surface morphology to the type localities. A comparison of these images and arsenic concentrations showed that the postulate is valid for over 80 percent of cases. Where this is not valid, this could indicate that the subsurface

  18. Prevalence of Tinea capitis in school going children in Kolkata, West Bengal.

    PubMed

    Kundu, D; Mandal, L; Sen, G

    2012-07-01

    In recent years the incidence of Tinea capitis, infection of scalp by dermatophytes, has increased in United Kingdom and North America. The trend may be similar in India. The objective of this study is to find the prevalence of Tinea capitis in school going urban children in Kolkata, West Bengal state. The present study is a cross-sectional study conducted in a government higher primary school in Kolkata. Totally 505 students were screened and 52 were diagnosed to have Tinea capitis by clinical examination, giving a prevalence rate of 10% among school children. Prevalence rates among the age groups of 6-8, 9-11 and 12-14 years were almost the same, ranging from 9 to 11%. The prevalence rate was significantly high among the boys (14%). There was no significant difference in prevalence of infection among coconut oil users and castor oil users. Measures of general hygiene were similar among those who were infected with Tinea capitis and those who were not. The commonest clinical type of infection found was dull grey patches. Itching with hair loss was the major symptom and most of the infected children had cervical lymphadenopathy. The potassium hydroxide studies revealed endothrix spores in majority of samples. Tinea capitis in prevalent in school going urban children in Kolkata, West Bengal state and necessary measures must be undertaken to curtail this incidence.

  19. Intense Convective Activity Over Northern Bay of Bengal during Late Southwest Monsoon

    NASA Astrophysics Data System (ADS)

    Mathew, S.; Venkatesan, R.; Natesan, U.; G, L.

    2016-02-01

    Warming of the northern Bay of Bengal during late southwest monsoon was very much influenced by the intensity of freshening by river discharges. The inter-annual variability of freshening and associated warming was analyzed for 2011 to 2015, with the help of in-situ data obtained from the moored buoys deployed at specific locations in northern Bay of Bengal. The shoaling of mixed layer depth associated with the advection of freshwaters has favored intense warming and supported convective activity thereby. The year 2011 recorded highest freshening with salinity touched as low as 21.3 p.s.u.; with the heavy river discharges, resulted from intense rainfall over catchment areas of rivers that discharged into the bay, due to positive Indian Ocean Dipole and La-Nina affect. It has resulted in intense warming of the surface temperature by 2°C, which persisted for nearly three weeks. The year 2014 was least fresh, with no signature of freshening and associated warming. The latent heat flux term computed from the moored buoy using the COARE 3.5 algorithm showed increased loss of latent heat flux during the late monsoon associated with the warming. It directly supported increased convective activity and delayed the withdrawal of monsoon activity from Indian sub-continent. Two depressions with intense convective activity formed over bay during September of 2011 which delayed the withdrawal of monsoon by three weeks.

  20. A simplified strategy for sensitive detection of Rose rosette virus compatible with three RT-PCR chemistries.

    PubMed

    Dobhal, Shefali; Olson, Jennifer D; Arif, Mohammad; Garcia Suarez, Johnny A; Ochoa-Corona, Francisco M

    2016-06-01

    Rose rosette disease is a disorder associated with infection by Rose rosette virus (RRV), a pathogen of roses that causes devastating effects on most garden cultivated varieties, and the wild invasive rose especially Rosa multiflora. Reliable and sensitive detection of this disease in early phases is needed to implement proper control measures. This study assesses a single primer-set based detection method for RRV and demonstrates its application in three different chemistries: Endpoint RT-PCR, TaqMan-quantitative RT-PCR (RT-qPCR) and SYBR Green RT-qPCR with High Resolution Melting analyses. A primer set (RRV2F/2R) was designed from consensus sequences of the nucleocapsid protein gene p3 located in the RNA 3 region of RRV. The specificity of primer set RRV2F/2R was validated in silico against published GenBank sequences and in-vitro against infected plant samples and an exclusivity panel of near-neighbor and other viruses that commonly infect Rosa spp. The developed assay is sensitive with a detection limit of 1fg from infected plant tissue. Thirty rose samples from 8 different states of the United States were tested using the developed methods. The developed methods are sensitive and reliable, and can be used by diagnostic laboratories for routine testing and disease management decisions. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Bio-inspired Ni2+-polyphenol hydrophilic network to achieve unconventional high-flux nanofiltration membranes for environmental remediation.

    PubMed

    You, Fangjie; Xu, Yanchao; Yang, Xiaobin; Zhang, Yanqiu; Shao, Lu

    2017-06-01

    A novel Ni 2+ -polyphenol network was designed as an excellent bio-coating by a one-step strategy to obtain nanofiltration membranes, possessing unconventional high water flux up to 56.1 L m -2 h -1 bar -1 with rose bengal (RB) rejection above 95%. This study provides a facile approach to prepare highly-efficient nanofiltration membranes for wastewater remediation.

  2. Treatment of Breast Tumors using Pulsed HIFU for Delivery and Activation of Sonosensitizers

    DTIC Science & Technology

    2010-02-14

    ABSTRACT High intensity focused ultrasound ( HIFU ) has been combined with a Rose Bengal derivative (RB2) to provide a synergistic cytotoxicity requiring...vivo in combination with cavitation driven by high intensity focused ultrasound ( HIFU ). Applying HIFU in pulsed mode (to avoid overheating) has...treated and control tumors. 15. SUBJECT TERMS high intensity focused ultrasound , sonodynamic, cavitation, free radicals, chemotherapy, targeted

  3. Treatment of Breast Tumors using Pulsed HIFU for Delivery and Activation of Sonosensitizers

    DTIC Science & Technology

    2009-08-01

    ABSTRACT High intensity focused ultrasound ( HIFU ) has been combined with a Rose Bengal derivative (RB2) to provide a synergistic cytotoxicity requiring the...by high intensity focused ultrasound ( HIFU ). Applying HIFU in pulsed mode (to avoid overheating) has shown promise in improving the penetration of...ablation for breast cancer treatment. 15. SUBJECT TERMS high intensity focused ultrasound , sonodynamic, cavitation, free radicals, chemotherapy

  4. Controls on groundwater flow in the Bengal Basin of India and Bangladesh: Regional modeling analysis

    USGS Publications Warehouse

    Michael, H.A.; Voss, C.I.

    2009-01-01

    Groundwater for domestic and irrigation purposes is produced primarily from shallow parts of the Bengal Basin aquifer system (India and Bangladesh), which contains high concentrations of dissolved arsenic (exceeding worldwide drinking water standards), though deeper groundwater is generally low in arsenic. An essential first step for determining sustainable management of the deep groundwater resource is identification of hydrogeologic controls on flow and quantification of basin-scale groundwater flow patterns. Results from groundwater modeling, in which the Bengal Basin aquifer system is represented as a single aquifer with higher horizontal than vertical hydraulic conductivity, indicate that this anisotropy is the primary hydrogeologic control on the natural flowpath lengths. Despite extremely low hydraulic gradients due to minimal topographic relief, anisotropy implies large-scale (tens to hundreds of kilometers) flow at depth. Other hydrogeologic factors, including lateral and vertical changes in hydraulic conductivity, have minor effects on overall flow patterns. However, because natural hydraulic gradients are low, the impact of pumping on groundwater flow is overwhelming; modeling indicates that pumping has substantially changed the shallow groundwater budget and flowpaths from predevelopment conditions. ?? Springer-Verlag 2009.

  5. Controls on groundwater flow in the Bengal Basin of India and Bangladesh: regional modeling analysis

    NASA Astrophysics Data System (ADS)

    Michael, Holly A.; Voss, Clifford I.

    2009-11-01

    Groundwater for domestic and irrigation purposes is produced primarily from shallow parts of the Bengal Basin aquifer system (India and Bangladesh), which contains high concentrations of dissolved arsenic (exceeding worldwide drinking water standards), though deeper groundwater is generally low in arsenic. An essential first step for determining sustainable management of the deep groundwater resource is identification of hydrogeologic controls on flow and quantification of basin-scale groundwater flow patterns. Results from groundwater modeling, in which the Bengal Basin aquifer system is represented as a single aquifer with higher horizontal than vertical hydraulic conductivity, indicate that this anisotropy is the primary hydrogeologic control on the natural flowpath lengths. Despite extremely low hydraulic gradients due to minimal topographic relief, anisotropy implies large-scale (tens to hundreds of kilometers) flow at depth. Other hydrogeologic factors, including lateral and vertical changes in hydraulic conductivity, have minor effects on overall flow patterns. However, because natural hydraulic gradients are low, the impact of pumping on groundwater flow is overwhelming; modeling indicates that pumping has substantially changed the shallow groundwater budget and flowpaths from predevelopment conditions.

  6. Towards dosimetry for photodynamic diagnosis with the low-level dose of photosensitizer.

    PubMed

    Buzalewicz, Igor; Hołowacz, Iwona; Ulatowska-Jarża, Agnieszka; Podbielska, Halina

    2017-08-01

    Contemporary medicine does not concern the issue of dosimetry in photodynamic diagnosis (PDD) but follows the photosensitizer (PS) producers recommendation. Most preclinical and clinical PDD studies indicate a considerable variation in the possibility of visualization and treatment, as e.g. in case of cervix lesions. Although some of these variations can be caused by the different histological subtypes or various tumor geometries, the issue of varying PS concentration in the tumor tissue volume is definitely an important factor. Therefore, there is a need to establish the objective and systematic PDD dosimetry protocol regarding doses of light and photosensitizers. Four different irradiation sources investigated in PDD (literature) were used for PS excitation. The PS luminescence was examined by means of the non-imaging (spectroscopic) and imaging (wide- and narrow-field of view) techniques. The methodology for low-level intensity photoluminescence (PL) characterization and dedicated image processing algorithm for PS luminescence images analysis were proposed. Further, HeLa cells' cultures penetration by PS was studied by a confocal microscopy. Reducing the PS dose with the choice of proper photoexcitation conditions decreases the PDD procedure costs and the side effects, not affecting the diagnostic efficiency. We determined in vitro the minimum incubation time and photosensitizer concentration of Photolon for diagnostic purposes, for which the Photolon PL can still be observed. It was demonstrated that quantification of PS concentration, choice of proper photoexcitation source, appropriate adjustment of light dose and PS penetration of cancer cells may improve the low-level luminescence photodynamic diagnostics performance. Practical effectiveness of the PDD strongly depends on irradiation source parameters (bandwidth, maximum intensity, half-width) and their optimization is the main conditioning factor for low-level intensity and low-cost PDD. Copyright © 2017

  7. Photo-induced oxidative damage to dissolved free amino acids by the photosensitizer polycyclic musk tonalide: Transformation kinetics and mechanisms.

    PubMed

    Fang, Hansun; Gao, Yanpeng; Wang, Honghong; Yin, Hongliang; Li, Guiying; An, Taicheng

    2017-05-15

    Residue from the polycyclic musks (PCMs) in household and personal care products may harm human beings through skin exposure. To understand the health effects of PCMs when exposed to sunlight at molecular level, both experimental and computational methods were employed to investigate the photosensitized oxidation performance of 19 natural amino acids, the most basic unit of life. Results showed that a typical PCM, tonalide, acts as a photosensitizer to significantly increase photo-induced oxidative damage to amino acids. Both common and exceptional transformation pathways occurred during the photosensitization damage of amino acids. Experimental tests further identified the different mechanisms involved. The common transformation pathway occurred through the electron transfer from α amino-group of amino acids, accompanying with the formation of O 2 •- . This pathway was controlled by the electronic density of N atom in α amino-group. The exceptional transformation pathway was identified only for five amino acids, mainly due to the reactions with reactive oxygen species, e.g. 1 O 2 and excited triplet state molecules. Additionally, tonalide photo-induced transformation products could further accelerate the photosensitization of all amino acids with the common pathway. This study may support the protection of human health, and suggests the possible need to further restrict polycyclic musks use. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. The threat from sea and land. Regional report 2: the Bay of Bengal.

    PubMed

    1994-01-01

    This article reports on the environmental threat caused by the Bay of Bengal on the economic situation in Bangladesh and India. More than four-fifths of Bangladesh amount to an extended delta at the confluence of one of the largest river systems in the world, comprising the Ganges, Brahmaputra, and Meghna. In the Brahmaputra watershed, the rate of deforestation caused soil erosion in the Himalayas is five times as much as in the geological past. This sediment loading is often considered to be a prime factor in downstream flooding. Because of this, Bangladesh agriculture products were damaged, which led to economic instability. Furthermore, as a result of the combined impacts of population growth, poverty, no land, and inadequate food supplies, many migrated into the neighboring Indian areas. Moreover, the susceptibility of the Bay of Bengal to cyclones has caused a great number of deaths leaving millions of people homeless. Cyclone episodes are expected to be more frequent as global warming continues. Furthermore, Bangladesh was estimated to be only 5 meters above sea level, which is considered vulnerable to sea level rise. On top of these problems, trouble from the other side of Bangladesh was also predicted with the combined outflow of the Ganges, Brahmaputra, and Meghna leading to more national damage.

  9. The development of mental hospitals in West Bengal: A brief history and changing trends.

    PubMed

    Bhattacharyya, Ranjan

    2018-02-01

    The communication between G. S Bose and Sigmund Freud is a well-documented fact, and philosophical blend of rich cultural experiences is unique to modification of traditional psychoanalysis in the context of development of psychiatry in West Bengal. The Calcutta lunatic asylum was established at Bhowanipore, and first general hospital psychiatric unit was formed at R. G. Kar Medical College, Calcutta. Prof. Ajita Chakraborty was a pioneer to describe her struggling days in the early career and shared her views with experiences in her autobiography. The volume and quality of research work, especially in the field of epidemiology led by Dr. D. N. Nandi is worth mentioning. A jail had been converted to mental hospital which is the largest in terms of bed strength ( n = 350) at Berhampore, Murshidabad district where Kazi Nazrul Islam and Netaji Subhas Chandra Bose had spent some period as prisoner during British rules. Bankura was the first district in West Bengal to start District Mental Health program. The various nongovernmental organizations are working together in public-private partnership model or indigenous ways in tandem over years for the betterment of mental health services both at institutional and community level.

  10. Predictive model for photodynamic therapy with gold nanoparticles as vehicle for the photosensitizer delivery

    NASA Astrophysics Data System (ADS)

    Salas-García, I.; Fanjul-Vélez, F.; Ortega-Quijano, N.; Arce-Diego, J. L.

    2013-06-01

    Photodynamic Therapy offers multiple advantages to treat nonmelanoma skin cancer compared to conventional treatment techniques such as surgery, radiotherapy or chemotherapy. Among these advantages are particularly relevant its noninvasive nature, the use of non ionizing radiation and its high selectivity. However the therapeutic efficiency of the current clinical protocol is not complete in all the patients and depends on the type of pathology. Emerging strategies to overcome its current shortcomings include the use of nanostructures that can act as carriers for conventional photosensitizers and improve the treatment selectivity and provide a controlled release of the photoactive agent. In this work, a model for photodynamic therapy combined with gold nanocarriers for a photosensitizer commonly used in dermatology is presented and applied to a basal cell carcinoma in order to predict the cytotoxic agent spatial and temporal evolution.

  11. Determination of diagnostic standards on saturated soil extracts for cut roses grown in greenhouses.

    PubMed

    Franco-Hermida, John Jairo; Quintero, María Fernanda; Cabrera, Raúl Iskander; Guzman, José Miguel

    2017-01-01

    This work comprises the theoretical determination and validation of diagnostic standards for the analysis of saturated soil extracts for cut rose flower crops (Rosa spp.) growing in the Bogota Plateau, Colombia. The data included 684 plant tissue analyses and 684 corresponding analyses of saturated soil extracts, all collected between January 2009 and June 2013. The tissue and soil samples were selected from 13 rose farms, and from cultivars grafted on the 'Natal Briar' rootstock. These concurrent samples of soil and plant tissues represented 251 production units (locations) of approximately 10,000 m2 distributed across the study area. The standards were conceived as a tool to improve the nutritional balance in the leaf tissue of rose plants and thereby define the norms for expressing optimum productive potential relative to nutritional conditions in the soil. To this end, previously determined diagnostic standard for rose leaf tissues were employed to obtain rates of foliar nutritional balance at each analyzed location and as criteria for determining the diagnostic norms for saturated soil extracts. Implementing this methodology to foliar analysis, showed a higher significant correlation for diagnostic indices. A similar behavior was observed in saturated soil extracts analysis, becoming a powerful tool for integrated nutritional diagnosis. Leaf analyses determine the most limiting nutrients for high yield and analyses of saturated soil extracts facilitate the possibility of correcting the fertigation formulations applied to soils or substrates. Recommendations are proposed to improve the balance in soil-plant system with which the possibility of yield increase becomes more probable. The main recommendations to increase and improve rose crop flower yields would be: continuously check pH values of SSE, reduce the amounts of P, Fe, Zn and Cu in fertigation solutions and carefully analyze the situation of Mn in the soil-plant system.

  12. Determination of diagnostic standards on saturated soil extracts for cut roses grown in greenhouses

    PubMed Central

    Cabrera, Raúl Iskander

    2017-01-01

    This work comprises the theoretical determination and validation of diagnostic standards for the analysis of saturated soil extracts for cut rose flower crops (Rosa spp.) growing in the Bogota Plateau, Colombia. The data included 684 plant tissue analyses and 684 corresponding analyses of saturated soil extracts, all collected between January 2009 and June 2013. The tissue and soil samples were selected from 13 rose farms, and from cultivars grafted on the 'Natal Briar' rootstock. These concurrent samples of soil and plant tissues represented 251 production units (locations) of approximately 10,000 m2 distributed across the study area. The standards were conceived as a tool to improve the nutritional balance in the leaf tissue of rose plants and thereby define the norms for expressing optimum productive potential relative to nutritional conditions in the soil. To this end, previously determined diagnostic standard for rose leaf tissues were employed to obtain rates of foliar nutritional balance at each analyzed location and as criteria for determining the diagnostic norms for saturated soil extracts. Implementing this methodology to foliar analysis, showed a higher significant correlation for diagnostic indices. A similar behavior was observed in saturated soil extracts analysis, becoming a powerful tool for integrated nutritional diagnosis. Leaf analyses determine the most limiting nutrients for high yield and analyses of saturated soil extracts facilitate the possibility of correcting the fertigation formulations applied to soils or substrates. Recommendations are proposed to improve the balance in soil-plant system with which the possibility of yield increase becomes more probable. The main recommendations to increase and improve rose crop flower yields would be: continuously check pH values of SSE, reduce the amounts of P, Fe, Zn and Cu in fertigation solutions and carefully analyze the situation of Mn in the soil-plant system. PMID:28542547

  13. Characterization of biochemical traits of dog rose (Rosa canina L.) ecotypes in the central part of Iran.

    PubMed

    Javanmard, Milad; Asadi-Gharneh, Hossein Ali; Nikneshan, Pejman

    2018-07-01

    Dog rose (Rosa canina L.) is a wild native species in Iran, with a significant genetic diversity. This plant serves as a rich source of vitamin C, anthocyanins, phenolic contents and carotenoids. Rose hips have been used in several food products, as well as perfumery and cosmetics industries. In this research, we investigate biochemical characteristics of five dog rose ecotypes (Kopehjamshid, Zarneh, Miyankish, Aghcheh and Sadeghiyeh), that were collected from the central part of Iran (Isfahan province). Amounts of vitamin C, total carotenoids, total phenolic contents, total anthocyanins, macro and micro minerals were measured. Seed oil are extracted by soxhlet method and analysed by gas chromatography. The macro and micro minerals levels in the fruit vary significantly among these regions. The results of this study demonstrate that dog rose have great diversity and can be used in breeding programmes in order to increase nutrient values as a food resource additive.

  14. DNA Photosensitization by an "Insider": Photophysics and Triplet Energy Transfer of 5-Methyl-2-pyrimidone Deoxyribonucleoside.

    PubMed

    Bignon, Emmanuelle; Gattuso, Hugo; Morell, Christophe; Dumont, Elise; Monari, Antonio

    2015-08-03

    The main chromophore of (6-4) photoproducts, namely, 5-methyl-2-pyrimidone (Pyo), is an artificial noncanonical nucleobase. This chromophore has recently been reported as a potential photosensitizer that induces triplet damage in thymine DNA. In this study, we investigate the spectroscopic properties of the Pyo unit embedded in DNA by means of explicit solvent molecular-dynamics simulations coupled to time-dependent DFT and quantum-mechanics/molecular-mechanics techniques. Triplet-state transfer from the Pyo to the thymine unit was monitored in B-DNA by probing the propensity of this photoactive pyrimidine analogue to induce a Dexter-type triplet photosensitization and subsequent DNA damage. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Source of marine turbidites on the Andaman-Nicobar Islands: Nicobar Fan, Bengal Fan or paleo-Irrawaddy?

    NASA Astrophysics Data System (ADS)

    Carter, A.

    2017-12-01

    Marine turbidites from an axially fed submarine fan are intermittently exposed across the entire chain of the Andaman-Nicobar Islands. Known as the Andaman Flysch (AF) and loosely assigned to the Paleogene, it has been proposed that these rocks are sourced from the Himalaya and thus provide a unique window into early stages of orogenesis. Where the turbidites came from has been subject to debate; they are either Bengal Fan or forearc deposits cut off from the Bengal Fan and possibly sourced from the Irrawaddy delta. Following recent IODP drilling in the eastern Indian Ocean (Expeditions 354 and 362) it is now possible resolve this by comparing the provenance of AF turbidites with the Bengal and Nicobar Fans. The Andaman Flysch can be traced as detached outcrops all along the western side of the main islands of Andaman over a strike length of more than 200 km. Exposures along the east coast are confined to South Andaman Island. Petrographic and geochemical data show a common continental crust signal with minor contributions from arc material. But, there are also differences whereby west coast sandstones show significantly higher quartz content and less feldspars and rock fragments. Staurolite is also present in all samples from the western side, but is absent from east coast samples. Both detrital zircon U-Pb and Bulk rock Nd data record the presence of arc material likely from Myanmar. Detrital zircon data from the Nicobar Fan match the Andaman turbidites and indicate sources from the Greater and Tethyan Himalaya mixed with sediment from the Burmese arc. Transfer of Irrawaddy derived sediment to the Nicobar Fan is ruled out as sediment transfer across the fore-arc to the west was restricted by the then exposed Yadana and M8 highs in the north and the Sewell and Alcock Rises to the south. Sediment isopachs of the Martaban back arc basin, the main north-south-oriented depocentre in the Andaman Sea related to the development of the Thanlwin -Irrawaddy delta system

  16. Quantification of tidally-influenced seasonal groundwater discharge to the Bay of Bengal by seepage meter study

    NASA Astrophysics Data System (ADS)

    Debnath, Palash; Mukherjee, Abhijit

    2016-06-01

    Submarine groundwater discharges (SGD) play a major role in solute transport and nutrient flux to the ocean. We have conducted a spatio-temporal high-resolution lunar-tidal cycle-scale seepage meter experiment during pre-monsoon and post-monsoon seasons, to quantify the spatio-temporal patterns and variability of SGD, its terrestrial (T-SGD) and marine components (M-SGD). The measured daily average SGD rates range from no discharge to 3.6 m3 m-2 d-1 during pre-monsoon season and 0.08-5.9 m3 m-2 d-1 during post-monsoon seasons, depending on the tidal pattern. The uncertainty for SGD measurement is calculated as ±0.8% to ±11% for pre-monsoon and ±1.8% to ±17% for post-monsoon respectively. A linear, inverse relationship was observed between the calculated T-SGD and M-SGD components, which varied along the distance from the coast and position in the tidal-cycle, spatial and temporal (daily) variations of seepage rates within the lunar tidal cycle period distinctly demonstrate the influence of tides on groundwater seepage rate. As an instance, for the identification of the bulk discharge location, the centroid of the integrated SGD rate has been calculated and found to be near 20 m offshore area. The average discharge rate per unit area further extrapolated to total SGD fluxes to the Bay of Bengal from eastern Indian coast by extrapolation of the annual and seasonal fluxes observed in the study area, which are first direct/experimental estimate of SGD to the Bay of Bengal. Approximations suggest that in present-day condition, total average annual SGD to the Bay of Bengal is about 8.98 ± 0.6 × 108 m3/y. This is suggested that the SGD input to the ocean through the Bay of Bengal is approximately 0.9% of the global input from the inter-tidal zone and that has an implication on the mass balance of discharging solutes/nutrients to the global oceans. High T-SGD input is observed for all season, which is largest toward landward direction from the delineated saltwater

  17. Photosensitized H2 Production Using a Zinc Porphyrin-Substituted Protein, Platinum Nanoparticles, and Ascorbate with No Electron Relay: Participation of Good's Buffers.

    PubMed

    Clark, Emily R; Kurtz, Donald M

    2017-04-17

    Development of efficient light-driven splitting of water, 2H 2 O → 2H 2 + O 2 , often attempts to optimize photosensitization of the reductive and oxidative half-reactions individually. Numerous homogeneous and heterogeneous systems have been developed for photochemical stimulation of the reductive half reaction, 2H + + 2e - → H 2 . These systems generally consist of various combinations of a H + reduction catalyst, a photosensitizer (PS), and a "sacrificial" electron donor. Zinc(II)-porphyrins (ZnPs) have frequently been used as PSs for H 2 generation, but they are subject to various self-quenching processes in aqueous solutions. Colloidal platinum in nanoparticle form (Pt NP) is a classical H + reduction catalyst using ZnP photosensitizers, but efficient photosensitized H 2 generation requires an electron relay molecule between ZnP and Pt NP. The present report describes an aqueous system for visible (white) light-sensitized generation of H 2 using a protein-embedded Zn(II)-protoporphyrin IX as PS and Pt NP as H + reduction catalyst without an added electron relay. This system operated efficiently in piperazino- and morpholino-alkylsulfonic acid (Good's buffers), which served as sacrificial electron donors. The system also required ascorbate at relatively modest concentrations, which stabilized the Zn(II)-protoporphyrin IX against photodegradation. In the absence of an electron relay molecule, the photosensitized H 2 generation must involve formation of at least a transient complex between a protein-embedded Zn(II)-protoporphyrin IX species and Pt NP.

  18. Photosensitizing effects of nanometer TiO2 on chlorothalonil photodegradation in aqueous solution and on the surface of pepper.

    PubMed

    Tan, Yong Qiang; Xiong, Hai Xia; Shi, Tao Zhong; Hua, Ri Mao; Wu, Xiang Wei; Cao, Hai Qun; Li, Xue De; Tang, Jun

    2013-05-29

    The present study examined the effects of anatase nanometer TiO2 on photochemical degradation of chlorothalonil in aqueous solution and on the plant surface. Results showed that nanometer TiO2 exhibited a strong photosensitizing effect on the degradation of chlorothalonil both in aqueous solution and on the surface of green pepper. The photosensitization rate was the highest in the sunlight compared to illumination under high-pressure mercury and UV lamps. Use of distinct hydroxyl radical scavengers indicated that nanometer TiO2 acted by producing hydroxyl radicals with strong oxidizing capacity. Notably, nanometer TiO2 facilitated complete photodegradation of chlorothalonil with no detectable accumulation of the intermediate chlorothalonil-4-hydroxy. Nanometer TiO2 was also active on the surface of green pepper under natural sunlight both inside and outside of plastic greenhouse. These results together suggest that nanometer TiO2 can be used as a photosensitizer to accelerate degradation of the pesticides under greenhouse conditions.

  19. Going Back to School: An Interview with Mike Rose

    ERIC Educational Resources Information Center

    Adams, Peter

    2017-01-01

    Mike Rose is a professor in the UCLA Graduate School of Education and Information Studies. He has taught in a wide range of educational settings - from elementary school to adult literacy and job training programs--and has directed an Educational Opportunity (EOP) tutorial center. He is an author and member of the National Academy of Education and…

  20. Carnegiea gigantea (Engelm.) Britton & Rose saguaro or giant cactus

    Treesearch

    Susan E. Meyer

    2008-01-01

    Saguaro - Carnegiea gigantea (Engelm.) Britton & Rose - has the northernmost distribution of any of the large, columnar cacti of the tropical and subtropical Americas. Formerly regarded as a member of the genus Cereus, it is now considered the single species of its own genus, Carnegiea. It is a principal indicator species of the Sonoran Desert and is found at...