Photochemistry and Photobiology

Cover image for Vol. 90 Issue 3

May/June 2014

Volume 90, Issue 3

Pages 479–726

  1. Invited Review

    1. Top of page
    2. Invited Review
    3. Rapid Communication
    4. Research Articles
    5. Research Notes
    1. You have free access to this content
      Shade Provision for UV Minimization: A Review (pages 479–490)

      Alfio V. Parisi and David J. Turnbull

      Version of Record online: 4 FEB 2014 | DOI: 10.1111/php.12237

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      Providing and using natural and built shade is an effective protection measure against harmful UV. This article describes the factors that must be addressed to ensure quality, effective, well-designed shade and recommends best practice approaches to improving the protection factor of shade structures. It identifies examples of interventions to increase shade availability and use, and examples of effective shade based on measured protection factors or measured reductions in UV exposures. Finally, this article considers examples of best practice for undertaking shade audits.

  2. Rapid Communication

    1. Top of page
    2. Invited Review
    3. Rapid Communication
    4. Research Articles
    5. Research Notes
    1. The Effect of Loading Palladium on Zinc Oxide on the Photocatalytic Degradation of Methyl tert-Butyl Ether (MTBE) in Water (pages 491–495)

      Zaki S. Seddigi, Saleh A. Ahmed, Shahid P. Ansari, Naeema H. Yarkandi, Ekram Danish, Abdullah Abu Alkibash, Mohammed D. Y. Oteef and Shakeel Ahmed

      Version of Record online: 23 FEB 2014 | DOI: 10.1111/php.12242

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      Approximately complete removal of MTBE was achieved within 5 h by using ZnO particles doped with 1% Pd. The efficient degradation of MTBE is due to the higher concentration of the hydroxyl radicals and to the presence of Pd that controls the recombination of photogenerated electron hole pair.

  3. Research Articles

    1. Top of page
    2. Invited Review
    3. Rapid Communication
    4. Research Articles
    5. Research Notes
    1. Characterization of the Triplet State of Tanshinone IIA and its Reactivity by Laser Flash Photolysis (pages 496–502)

      Kun Li, Qin Zhang, Mei Wang, Rongrong Zhu, Xiaoyu Sun, Xianzheng Wu and Shi-Long Wang

      Version of Record online: 27 JAN 2014 | DOI: 10.1111/php.12220

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      Photosensitization by energy transfer from triplet state of photosensitizer to Tan IIA or direct photoexcitation of Tan IIA by 355 nm laser pulses lead to generation of triplet state of Tan IIA which can react with DMA and TBHQ and PGA via electron transfer in acetonitrile and experience self-quenching reaction via autooxidation in cyclohexane.

    2. Photophysical Properties of Metal Ion Functionalized NaY Zeolite (pages 503–510)

      Tian-Wei Duan and Bing Yan

      Version of Record online: 28 JAN 2014 | DOI: 10.1111/php.12235

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      A series of luminescent ion exchanged zeolite are synthesized by introducing various ions into NaY zeolite. The produced materials can be divided into three types: metal exchanged zeolite, rare-earth exchanged NaY zeolite modified with Y3+ and rare-earth exchanged NaY zeolite modified with Zn2+.

    3. Triplet–Triplet Energy Transfer from a UV-A Absorber Butylmethoxydibenzoylmethane to UV-B Absorbers (pages 511–516)

      Azusa Kikuchi, Nozomi Oguchi-Fujiyama, Kazuyuki Miyazawa and Mikio Yagi

      Version of Record online: 6 JAN 2014 | DOI: 10.1111/php.12222

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      The intermolecular triplet–triplet energy transfer from 4-tert-butyl-4′-methoxydibenzolymethane (BMDBM) to octocrylene (OCR) has been observed by measuring the phosphorescence decay of BMDBM following a 355 nm laser excitation. The lifetime of the lowest excited triplet state of BMDBM is significantly reduced in the presence of OCR. Our methodology of energy-donor phosphorescence decay measurements can be applied to the study of the triplet–triplet energy transfer between UV absorbers even if the energy acceptor is nonphosphorescent.

    4. Energy Harvesting Capability of Lipid-Merocyanine Macromolecules: A New Design and Performance Model Development (pages 517–521)

      Lobat Tayebi, Masoud Mozafari, Rita El-khouri, Parvaneh Rouhani and Daryoosh Vashaee

      Version of Record online: 28 NOV 2013 | DOI: 10.1111/php.12193

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      Capacitor charging time reduced and open circuit voltage enhanced significantly in the newly designed lipid-merocyanine photoelectrochemical cell.

    5. Kinetics of Photosynthetic Response to Ultraviolet and Photosynthetically Active Radiation in Synechococcus WH8102 (CYANOBACTERIA) (pages 522–532)

      Glaucia M. Fragoso, Patrick J. Neale, Todd M. Kana and Alicia L. Pritchard

      Version of Record online: 28 NOV 2013 | DOI: 10.1111/php.12202

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      We studied the responses of PSII quantum yield, carbon fixation and oxygen evolution in Synechococcus WH8102 under levels of PAR and UVR that are representative of a mixed layer from oligotrophic waters. Fluorescence kinetics measurements showed that these radiation levels inhibited PSII activity, however, an apparent induction of photoprotection was observed. Although oxygen uptake is a mechanism of photoprotection when cells are exposed to increase levels of PAR, our results show that this is not an important strategy against UVR.

    6. Photoinhibition of Cyanobacteria and its Application in Cultural Heritage Conservation (pages 533–543)

      Paul Hsieh, Jens Z. Pedersen and Laura Bruno

      Version of Record online: 10 DEC 2013 | DOI: 10.1111/php.12208

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      To our knowledge, we are the first group that applies photoinhibition in the field of cultural heritage conservation. Because cyanobacteria are rich in Chl a and phycobiliproteins that can be excited by light to generate ROS, exposure of cyanobacteria to light beyond the turnover intensity may result in photoinhibition of photosynthesis, photobleaching of pigments and photodamage to the cells. Practically, red, green or white illumination can be tested at night in situ in the dim catacombs, caves and underground chambers, without disturbing the tourists, and without introducing any harmful chemicals to humans, to environment, or to the cultural heritage.

    7. Reflectance and Cyclic Electron Flow as an Indicator of Drought Stress in Cotton (Gossypium hirsutum) (pages 544–551)

      Ruchi Singh, Jishnu Naskar, Uday V. Pathre and Pramod A. Shirke

      Version of Record online: 14 DEC 2013 | DOI: 10.1111/php.12213

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      We observed that in Gossypium hirsutum, during water limitation, Chlorophyll b showed the best correlation with reflectance at 731 nm and is a good indicator of drought. During mild water stress photosystem I and photosystem II is protected from photoinhibition by high cyclic electron flow (CEF) and nonphotochemical quenching. While during severe drought stress, linear electron flow decreases sharply in comparison to CEF. CEF play a major role in G. hirsutum leaves during mild as well as under severe water stresses and is thus a good indicator of drought.

    8. Scrambled Self-Assembly of Bacteriochlorophylls c and e in Aqueous Triton X-100 Micelles (pages 552–559)

      Yoshitaka Saga, Tatsuya Saiki, Naoya Takahashi, Yutaka Shibata and Hitoshi Tamiaki

      Version of Record online: 24 DEC 2013 | DOI: 10.1111/php.12219

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      Bacteriochlorophyll (BChl) e was coassembled with BChl c in Triton X-100 micelles in aqueous solutions. The spectral features and the decomposition behaviors of the scrambled self-aggregates suggest that BChls c and e are not spatially separated; they are homogenously distributed over the self-aggregates to give electronic spectra that are different from those of the aggregate consisting solely of each pigment.

    9. Photoacclimation Responses of the Brown Macroalga Sargassum Cymosum to the Combined Influence of UV Radiation and Salinity: Cytochemical and Ultrastructural Organization and Photosynthetic Performance (pages 560–573)

      Luz K. Polo, Marthiellen R. de L. Felix, Marianne Kreusch, Debora T. Pereira, Giulia B. Costa, Carmen Simioni, Luciane C. Ouriques, Fungyi Chow, Fernanda Ramlov, Marcelo Maraschin, Zenilda L. Bouzon and Éder C. Schmidt

      Version of Record online: 10 JAN 2014 | DOI: 10.1111/php.12224

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      The figure shows the brown macroalga Sargassum cymosum have protective mechanism against oxidative stress, making defense against UVR more efficient. After exposure to UVR, S. cymosum increased cell wall thickness, physodes and presence of phenolic compounds.

    10. Photobiological Interactions of Blue Light and Photosynthetic Photon Flux: Effects of Monochromatic and Broad-Spectrum Light Sources (pages 574–584)

      Kevin R. Cope, M. Chase Snowden and Bruce Bugbee

      Version of Record online: 18 JAN 2014 | DOI: 10.1111/php.12233

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      Blue light (BL) has profound effects on leaf expansion and stem elongation but the interactions of BL with other wavelengths of photosynthetically active radiation and with total PPF are poorly characterized. We used three broad-spectrum and four monochromatic LED arrays at two photosynthetic photon flux (PPF) to quantify BL effects on plant growth and development. Regardless of PPF, BL was necessary to prevent shade-avoidance responses in lettuce and radish but not pepper. Leaf expansion was altered by a unique interaction of BL with PPF. Surprisingly, there were few additional interactions of BL between monochromatic and broad-spectrum light sources.

    11. Synthesis and Characterization of Near-Infrared Absorbing Water Soluble Squaraines and Study of their Photodynamic Effects in DLA Live Cells (pages 585–595)

      Kulathinte M. Shafeekh, Mohanannair S. Soumya, Moochikkadavath A. Rahim, Annie Abraham and Suresh Das

      Version of Record online: 17 FEB 2014 | DOI: 10.1111/php.12236

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      Synthesis, photophysical properties and photodynamic effects in DLA live cells of three water soluble squaraine dyes, SQDI, SQMI and ASQI, are presented. On photoirradiation, both the SQDI and SQMI generate singlet oxygen where both the dyes undergoing oxidation reactions with the singlet oxygen generated, whereas ASQI was stable and did not react with the singlet oxygen. In vitro cytotoxicity studies of these dyes in DLA cells were performed using Trypan blue dye exclusion method and intracellular generation of ROS was confirmed using dichlorofluorescein assay after the in vitro PDT.

    12. Photodamage in a Mitochondrial Membrane Model Modulated by the Topology of Cationic and Anionic Meso-Tetrakis Porphyrin Free Bases (pages 596–608)

      Cintia Kawai, Juliana C. Araújo-Chaves, Taciana Magrini, Camila O. C. C. Sanches, Sandra M. S. Pinto, Herculano Martinho, Nasser Daghastanli and Iseli L. Nantes

      Version of Record online: 23 JAN 2014 | DOI: 10.1111/php.12228

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      TMPyP binds to the liposome and generates singlet oxygen from molecular oxygen dissolved into bilayer. TPPS4 transfers electronic excitation to bulk molecular oxygen and generates singlet oxygen that travels through solution and attacks a distant lipid bilayer.

    13. Inactivation of Bacillus subtilis Spores Using Various Combinations of Ultraviolet Treatment with Addition of Hydrogen Peroxide (pages 609–614)

      Yiqing Zhang, Lingling Zhou, Yongji Zhang and Chaoqun Tan

      Version of Record online: 21 JAN 2014 | DOI: 10.1111/php.12210

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      The facility used in the experiments was a collimated beam apparatus containing a low-pressure mercury lamp. Petri dishes (90 mm diameter) with 40 mL samples were exposed to the UV in the collimated beam apparatus and stirred gently by a magnetic stirring apparatus. The inactivation of Bacillus subtilis spores of various combinations of UV treatment and H2O2 addition were compared, including sequential (UV-H2O2, H2O2–UV) and simultaneous (UV/H2O2) processes.

    14. Role of Ozone in UV-C Disinfection, Demonstrated by Comparison between Wild-Type and Mutant Conidia of Aspergillus niger (pages 615–621)

      Jing Liu, Lin Zhou, Ji-Hong Chen, Wang Mao, Wen-Jian Li, Wei Hu, Shu-Yang Wang and Chun-Ming Wang

      Version of Record online: 7 JAN 2014 | DOI: 10.1111/php.12217

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      The effect of UV light was divided into two parts: UV irradiation and the concomitantly generated ozone. The role of ozone in the disinfection of UV–C was illustrated through comparing wild-type (CON1) and mutant (MUT1) Aspergillus niger conidia. The results indicated that melanin protected A. niger against UV disinfection in two ways: absorbing UV light (UV screening) and scavenging free radicals. The synergistic effect of UV irradiation and ozone exhibited the most potent fungicidal results. So the direct exposure to UV irradiation and ozone were both necessary for thorough disinfection.

    15. Inactivation of Bacteriophage Infecting Bacteroides Strain GB124 Using UV-B Radiation (pages 622–627)

      David Diston, James E. Ebdon and Huw D. Taylor

      Version of Record online: 10 JAN 2014 | DOI: 10.1111/php.12223

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      Bacteriophage infecting Bacteroides fragilis strain GB-124 are a useful tool in determining the source of fecal pollution within aquatic environments. Here we present insights into the UV-B inactivation ecology of this important phage group by conducting controlled laboratory collimated-beam UV-B irradiation experiments. Results indicate that B124 phage may be inactivated at levels of UV-B commonly recorded in the environment, and inactivation potential should be considered when interpreting environmental B124 phage data.

    16. Antimicrobial Photodynamic Efficiency of Novel Cationic Porphyrins towards Periodontal Gram-positive and Gram-negative Pathogenic Bacteria (pages 628–640)

      Chandra Sekhar Prasanth, Suneesh C. Karunakaran, Albish K. Paul, Vesselin Kussovski, Vanya Mantareva, Danaboyina Ramaiah, Leslie Selvaraj, Ivan Angelov, Latchezar Avramov, Krishnankutty Nandakumar and Narayanan Subhash

      Version of Record online: 17 DEC 2013 | DOI: 10.1111/php.12198

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      We describe the synthesis and in vitro photodyanamic activity of two cationic porphyrin derivatives using Gram-positive as well as Gram-negative bacteria. These porphyrin derivatives exhibited favorable photophysical properties including high quantum yields of the triplet excited state and singlet oxygen generation efficiency. Furthermore, the in vitro studies indicated that these derivatives accumulate into bacterial cells and biofilms, and exhibit high antibacterial activity upon NIR excitation. Our results demonstrate that these cationic porphyrins can act as sensitizers for effective photoinactivation of bacterial strains associated with periodontitis and thereby their potential application in antibacterial photodynamic therapy.

    17. Hydrogel-Forming and Dissolving Microneedles for Enhanced Delivery of Photosensitizers and Precursors (pages 641–647)

      Ryan F. Donnelly, Desmond I. J. Morrow, Maelíosa T. C. McCrudden, Ahlam Zaid Alkilani, Eva M. Vicente-Pérez, Conor O'Mahony, Patricia González-Vázquez, Paul A. McCarron and A. David Woolfson

      Version of Record online: 5 DEC 2013 | DOI: 10.1111/php.12209

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      We present novel dissolving and hydrogel-forming microneedle arrays (MN) that can be applied in a one-step fashion and are intended to enhance delivery of photosensitizers and photosensitizer precursors. Both dissolving and hydrogel-forming MN proved effective in in vitro studies and we are now proceeding with animal investigations prior to preliminary human evaluation of technology with the potential to improve therapeutic outcomes for patients with nodular skin lesions.

    18. Novel Porphyrazine Derivatives show Promise for Photodynamic Therapy despite Restrictions in Hydrophilicity (pages 648–658)

      Tamarisk K. Horne and Marianne J. Cronjé

      Version of Record online: 21 JAN 2014 | DOI: 10.1111/php.12231

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      Complexing of ligands to photosensitizers (Ps) can enhance solubility, cell-surface recognition and tissue specificity for applications in Photodynamic Therapy (PDT). Nine carbohydrate-functionalized porphyrazine (Pz-galactopyranose/methyl-ribose) derivatives with H2, Zn(II) or Ni(II) cores were analyzed for potential use in PDT.

      • Derivatives solubilized in DCM and tetrahydrofuran were cytotoxic; encapsulation in DCM-based PEG-DSPE5000-PBS was biologically suitable.
      • No correlation between core ion, carbohydrate type and peripheral position was revealed via absorption spectra analyses. Encapsulation efficiency (%EE): Zn(II) (60–92%) > H2 (5–34%) > Ni(II) (4–21%).
      • Phototoxicity of Zn(II)Pz derivatives showed highest efficiency following excitation in MCF-7 cells, and show promise as anticancer PDT agents.
    19. Gold Nanorod-Assembled PEGylated Graphene-Oxide Nanocomposites for Photothermal Cancer Therapy (pages 659–666)

      Uuriintuya Dembereldorj, Seon Young Choi, Erdene-Ochir Ganbold, Nam Woong Song, Doseok Kim, Jaebum Choo, So Yeong Lee, Sehun Kim and Sang-Woo Joo

      Version of Record online: 5 DEC 2013 | DOI: 10.1111/php.12212

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      Gold nanorod-attached PEGylated graphene-oxide nanocomposites were tested for a photothermal platform both in vitro and in vivo.

    20. Effect of Laser Phototherapy on Enzymatic Activity of Salivary Glands of Hamsters Treated with 5-Fluorouracil (pages 667–672)

      Luana Campos, José Nicolau, Victor E. Arana-Chavez and Alyne Simões

      Version of Record online: 28 NOV 2013 | DOI: 10.1111/php.12195

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      The chemotherapeutic agent 5-Fluorouracil clearly affects the submandibular and sublingual glands function, causing an increase in the activity of lactate dehydrogenase and antioxidant enzymes, such as catalase and peroxidase, as well as a decrease in superoxide dismutase activity of glands; however, the LPT is a promising therapy to modulate these harmful effects.

    21. Photosensitive and Biomimetic Core–Shell Nanofibrous Scaffolds as Wound Dressing (pages 673–681)

      Guorui Jin, Molamma P. Prabhakaran and Seeram Ramakrishna

      Version of Record online: 4 FEB 2014 | DOI: 10.1111/php.12238

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      A photosensitive polymer, namely, poly (3-hexylthiophene) is encapsulated within the core–shell-structured Gel/PLLCL fibers by coaxial electrospinning. The proliferation of human dermal fibroblasts was significantly improved on the core–shell nanofibers under light stimulation compared to fibroblasts on the same scaffold under nonstimulated condition. Moreover, the stem cells on the photosensitive scaffolds under light stimulation were more likely to differentiate into epidermal lineages compared to cells without stimulation. Our results suggest that the photosensitive core–shell nanofibers can serve as a novel substrate to promote skin regeneration.

    22. Early Diagnosis of Colorectal Cancer in Rats With DMH Induced Carcinogenesis by Means of Urine Autofluorescence Analysis (pages 682–685)

      Zuzana Šteffeková, Anna Birková, Alojz Bomba and Mária Mareková

      Version of Record online: 15 FEB 2014 | DOI: 10.1111/php.12240

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      Cancer is one of the most highlighted topics of current research. Early detection of this disease allows more effective therapy, hence higher chance of cure. Application of fluorescence spectral techniques into oncological diagnostic is one of the potential alternatives. Chemically induced carcinogenesis in rats is widely used model for exploration of various aspects of colorectal cancer. This study shows value of discriminate analysis of urine fluorescent fingerprint between healthy control group of rats and those with dimethylhydrazine induced early lesions of colorectal cancer. Using fluorescence spectroscopy significant difference (P < 0.05) between both of group was achieved.

    23. Practical Labeling Methodology for Choline-Derived Lipids and Applications in Live Cell Fluorescence Imaging (pages 686–695)

      Caishun Li, Jessie A. Key, Feng Jia, Arpan Dandapat, Soo Hur and Christopher W. Cairo

      Version of Record online: 31 JAN 2014 | DOI: 10.1111/php.12234

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      Fluorescent probes can be used to investigate the structure and dynamics of the plasma membrane. Exogenous fluorescent lipid probes which integrate into the membrane are often used for this purpose. In this study, we investigate the utility of metabolic labeling of phosphocholine-derived lipids for introducing fluorescent probes. Using synthetic fluorophores that react with bioorthogonal metabolic labels, we labeled live cell membranes. We demonstrate that these labeled lipids can be used for a variety of applications including imaging, measurement of lipid dynamics (lateral diffusion) and chemical adhesion of the cells to reactive surfaces.

    24. Effect of Light on Expression of Clock Genes in Xenopus laevis Melanophores (pages 696–701)

      Maria Nathália de Carvalho Magalhães Moraes, Maristela de Oliveira Poletini, Bruno Cesar Ribeiro Ramos, Leonardo Henrique Ribeiro Graciani de Lima and Ana Maria de Lauro Castrucci

      Version of Record online: 18 JAN 2014 | DOI: 10.1111/php.12230

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      In light-sensitive cells, environmental light may be transduced through melanopsins (pigment excited by short wavelength) which, in turn, regulates the machinery of endogenous molecular clock through an increase in Per1 expression. In a nonmammalian vertebrate cell line (X. laevis melanophore), we demonstrated that a blue-light pulse increases Per1 and Per2 expression, and that Per1 gene expression oscillates in a circadian fashion under light–dark cycle. Thus, these cells are a promising model to investigate the biological mechanisms involved in photoentrainment in peripheral clocks.

    25. Biochemical Composition and Antioxidant Properties of Lavandula angustifolia Miller Essential Oil are Shielded by Propolis Against UV Radiations (pages 702–708)

      Gismondi Angelo, Canuti Lorena, Grispo Marta and Canini Antonella

      Version of Record online: 28 JAN 2014 | DOI: 10.1111/php.12229

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      Propolis shields Lavandula angustifolia Miller essential oil from UV-induced photodegradation. Lavender biochemical components are strongly degraded by UV radiations and consequently their antioxidant properties, in in vitro assays and directly on B16F10 cells, are decreased. Propolis is proposed as highly efficient UV protective and antiradical additive for sunscreens, cosmetics and alimentary or pharmaceutical products containing plant extracts.

  4. Research Notes

    1. Top of page
    2. Invited Review
    3. Rapid Communication
    4. Research Articles
    5. Research Notes
    1. Photosensitized Damage Inflicted on Plasma Membranes of Live Cells by An Extracellular Generator of Singlet Oxygen—A Linear Dependence of A Lethal Dose on Light Intensity (pages 709–715)

      Mirosław Zarębski, Magdalena Kordon and Jurek W. Dobrucki

      Version of Record online: 6 JAN 2014 | DOI: 10.1111/php.12216

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      The influence of a dose rate, i.e. light intensity or photon flux, on the efficiency of induction of a photosensitized loss of integrity of plasma membranes of live cells in culture is described. We demonstrate that the size of the lethal dose of light is directly proportional to the intensity of the exciting light. Thus, the probability of a photon of the exciting light inflicting photosensitized damage on plasma membranes diminishes with increasing density of the incident photons.

    2. Novel Photodynamic Effect of a Psoralen-Conjugated Oligonucleotide for the Discrimination of the Methylation of Cytosine in DNA (pages 716–722)

      Asako Yamayoshi, Yohei Matsuyama, Mikihiko Kushida, Akio Kobori and Akira Murakami

      Version of Record online: 21 JAN 2014 | DOI: 10.1111/php.12232

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      We designed a psoralen-conjugated oligonucleotide (PS-oligo) for the discrimination of 5-methylcytosine (5-mC) in DNA. The cross-linking behavior of psoralen derivatives with pyrimidine bases, such as thymine, uracil and cytosine has been well discussed, but there are no reports which have examined whether cross-linking efficiency of psoralen with cytosine would be changed with or without C-5 methylation. We found that the cross-linking efficiency of PS-oligo with target-DNA containing 5-mC was greatly increased compared to the case of target-DNA without 5-mC, approximately seven-fold higher.

    3. Home Lighting Before Usual Bedtime Impacts Circadian Timing: A Field Study (pages 723–726)

      Helen J. Burgess and Thomas A. Molina

      Version of Record online: 7 FEB 2014 | DOI: 10.1111/php.12241

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      After sunset, we often turn on our lights at home. In this field study, we found that maximizing evening light at home in the 4 h before usual bedtime, delayed the dim light melatonin rhythm by about 1 h, when compared to dim light in the evening. These results highlight that evening light at home can delay central circadian timing and contribute to circadian misalignment.