bluuebunny/crossref_metadata_2025 huggingface dataset:
LASER FLASH SPECTROSCOPY OF METHYLENE BLUE WITH NUCLEIC ACIDS. EFFECTS OF IONIC STRENGTH AND pH
Authors: VAN DER PUTTEN WILHELM J. M. , KELLY JOHN M.
Published: January 2008

Abstract Laser flash spectroscopic measurements were made on methylene blue complexed to the synthetic polynucleotides poly[d(G‐C)] and poly[d(A‐T)] in solutions of varying ionic strength and pH. Triplet decay rates and rates of triplet quenching by oxygen have been measured for the polymer/ dye solutions. The triplet decay and oxygen quenching rates of methylene blue in complex with poly[d(A‐T)] are much less sensitive than those with poly[d(G‐C)] with respect to variations in ionic strength. It is also shown that protonation of the triplet state of MB+ with poly[d(A‐T)] is slower than that of free dye. These results indicate strong binding of the dye to poly[d(A‐T)]. Excitation of the MB+/poly[d(A‐T)] complex at 665 nm yielded single exponential decay kinetics, in contrast with excitation at 600 nm where double exponential kinetics were measured. This is tentatively assigned to excitation of dye dimer bound to this polymer.
A STEREOCHEMICAL MODEL FOR THE ACTIVE SITE OF PHOTOSYSTEM II HERBICIDES*
Authors: GARDNER GARY
Published: January 2008

Abstract Photosystem II herbicides act by blocking electron transport at the secondary electron acceptor ‘QB’, thought to be a non‐covalently bound plastoquinone. Recent evidence suggests that these compounds work by displacing the plastoquinone from its site in the thylakoid. Since the herbicides cannot act as electron carriers, electron transport is then blocked. In this report a model is presented for the site of action of Photosystem II herbicides that encompasses biochemical, biophysical, and structure‐activity considerations. The essence of the model is that Photosystem II herbicides are non‐reducible analogues of plastoquinone or its semiquinone anion. As examples of the ways in which known herbicidal classes fit the model, the possible interactions of diuron, atrazine, the putative urea‐triazine hybrid MBAT (the a‐methylbenzyl analogue of atrazine), and dinoseb with the active site are discussed. This model provides a stereochemical basis for herbicidal activity and offers a qualitative approach for the design of novel Photosystem II herbicides.
FLAVINS IN LIPOSOMES‐ANOMALOUS PHOTOCHEMICAL EFFECTS AT HIGH PIGMENT CONCENTRATIONS
Authors: HEELIS P. F. , PHILLIPS G. O. , LENCI F. , COLOMBETTI G.
Published: January 2008

Abstract Laser flash photolysis of riboflavin tetrabutyrate incorporated in lecithin liposomes has been studied as a function of the number of flavins per liposome, NRFTB.

Both the flavin triplet decay rate and its susceptibility to quenching by oxygen and glycyl‐tyrosine depend markedly on the value of NRFTB. The results are interpreted on the basis of the existence of two distinct locations for the flavin chromophore within the liposome structure.
RECOVERY OF VIRAL CAPACITY IN IRRADIATED EXPONENTIALLY GROWING CELLS
Authors: Sayed Nadira I. , Rupert Claud S.
Published: January 2008

Abstract—

Exponentially growing cells of the PtK‐2 line (ATCC No. CCL56, from the marsupial Potorous tridactylus) require protein and RNA synthesis in a limited period following UV‐radiation damage for optimal recovery as colony formers [Overberg et al. (1988) Mutat. Res. 194, 83–92]. Overall behavior suggests the operation of damage‐induced recovery processes. The capacity of confluent cell monolayers for infection with unirradiated herpes simplex virus 1 (HSV‐1) is sharply reduced by UV‐irradiation. We have followed capacity changes in exponentially growing cells after irradiation and varying amounts of photoreactivation by means of an infectious center assay. These changes closely parallel changes of colony formation. Spontaneous recovery of capacity in the dark occurs over approximately the same time period that the UV sensitivity of colony formation depends on macromolecular synthesis. The effect of photoreactivation is complementary rather than additive to this recovery, suggesting that the dark recovery in this period concerns pyrimidine dimers in cell DNA.
DIFFERENCE SPECTRA OF THE OXIDIZED INTERMEDIATES IN THE PHOTOSYNTHETIC OXYGEN‐EVOLVING SYSTEM: EVIDENCE FOR A SMALL S0→S1 ABSORPTION CHANGE
Authors: Lavergne Jearome
Published: January 2008

Abstract—

A consensus has emerged in the recent literature on the fact that the UV difference spectrum of the first oxidation step (S0→ S1) of the photosynthetic oxygen‐evolving complex is significantly different and generally smaller than the spectra of the higher oxidation steps (S0→ S1and S2→ S3). Discrepancies still persist, however, notably in the 300 nm region where the S0→ S1 change was either reported to be markedly smaller than the other changes, or, at variance, to have a similar amplitude. A novel approach is proposed here for estimating the ratio of these changes, requiring no estimate of the Kok model parameters, such as the initial S0/S1ratio, or damping coefficients. This was achieved by comparing the absorption difference between two fully deactivated states, differing only in their S0/S1, distribution, with the flash‐induced changes measured from these states. The results show that, at two wavelengths around 300 nm, the S0→ S1 change is at least 4 times, and probably 5–6 times smaller than the S0→ S1change.
IMAGE ANALYZER USED FOR DATA ACQUISITION IN PHOTOTROPISM STUDIES
Authors: Popescu T. , Zängler F. , Sturm B. , Fukshansky L.
Published: January 2008

Abstract— Equipment (video system and goniometric device) developed for the automatic acquisition of data, which can generally be used for testing movement responses of small organisms is presented. This relatively cheap setup, especially designed for kinetic testing of phycomyces phototropism, could also be used with very slight modifications to study phototropism in higher plants and even for other purposes in the study of cell and organism movements. It permits continuous automatic observation of bending angle as a function of time. The goniometric device permits a complete geometrical localization of the object to be analyzed, even time‐dependent if needed. The video‐system hardware consists of a CCD‐video camera (with a sensitivity maximum between 700 and 800 nm), light source (equipped with an IR‐filter), video monitor, video card (for image digitalization), video recorder, computer and computer interface. The last assures (through a parallel port of the computer) complete control of the setup; time coordination between computer, lamp, camera and video recorder is thus ensured. Both real time processing and analysis of previously recorded data can be performed. The system permits automatic observation of experiments over long time periods and provides a large amount of data assuring good statistics, which can be analysed quickly.
INTERACTION OF DIBUCAINEHCl LOCAL ANESTHETICS WITH BACTERIORHODOPSIN IN PURPLE MEMBRANE: A SPECTROSCOPIC STUDY
Authors: LIN C. T. , CHYAN Y. G. , KRESHECK G. C. , JR HERBERT C. BITTING , EL‐SAYED M. A.
Published: January 2008

Abstract

Several spectroscopic techniques (absorption, emission, transient absorption and differential scanning calorimetry–DSC) were used to investigate the deprotonation of dibucaine‐HCl in a hydrophobic environment, and the interaction sites and mechanisms of the local anesthetic dibucaine‐HCl on bacteriorhodopsin (bR) in purple membrane. The important results are summarized as follows: (1) the visible absorption features of native (γmax= 568 nm) and deionized (γmax= 608 nm) bR are sensitive to the amount of dibucaine‐HCl added; (2) the emission spectrum of dibucaine‐HCl embedded in the retinal‐free mutant bR is similar to that of dibucaine free base in Triton X‐100 micellar solutions; (3) the phosphorescence emission of dibucaine at 77 K is completely quenched by bR and the fluorescence quenching rate for the incorporated dibucaine‐HCl in bR was determined as kδ= 4.09 × 1013M‐1s‐1; (4) the incorporation of dibucaine‐HCl in bR inhibits the slow component rate of formation of M412 and decreases the amount of M412 formation in the photochemical cycle of bR; and (5) the thermal stability of native bR was measured by DSC in the presence and absence of dibucaine and yielded an endothermic transition at 95.9 ± 1.0°C with 13.6 J/g (3.25 ± 0.12 cal/g) of enthalpy changes. All observations suggest that the action site of the local anesthetic, dibucaine‐HCl, is near or at the chromophore, i.e. the retinal Schiff base of bR. The anesthetic action on bR purple membrane is probably via a specific site binding, but not a conformational mechanism.
EXCITED STATE PROPERTIES OF THE N‐(DEOXYGUANOSIN‐8‐YL)‐2‐AMINOFLUORENE ADDUCTS
Authors: HOUTE L. P. A. VAN , GRONDELLE R. VAN , RETEL J. , WESTRA J. G. , ZlNGER D. , SUTHERLAND J. C. , KIM S. K. , GEACINTOV N. E.
Published: January 2008

Abstract— The spectroscopic characteristics of adducts derived from the covalent binding of the carcinogen 2‐aminofluorene to the C8 position of deoxyguanosine [N‐(deoxyguanosin‐8‐yl)‐2‐amino‐fluorene, dGuo‐C8‐AF], and from an adduct of similar structure formed with the synthetic polynucleotide poly(dG‐dC)‐poly(dG‐dC), were investigated. At 77 K both adducts are characterized by well‐defined and rather narrow fluorescence emission spectra with maxima at 370 and 390 nm characteristic of the aromatic, monomolecular 2‐aminofluorene (AF) residue. In contrast, at room temperature, the fluorescence is characterized by a broad, structureless emission band with a maximum at 460 nm in aqueous mixtures, shifting to 415 nm in solvents of lower polarity (100% propanol); the maxima are located at intermediate wavelengths in solutions of different propanol/water compositions, and this emission is attributed to an excited state complex (exciplex). The fluorescence quantum yield decreases when either the solvent polarity or the temperature are increased, varying from 5.4% (100% propanol) to 0.04–0.05% (100% H2O). The fluorescence decay profiles of dGuo‐C8‐AF adducts (measured at the National Synchrotron Light Source facility at the Brookhaven National Laboratory) can be roughly, but not exactly, modeled in terms of two exponential decay components in the range of about 0.3–1.0 ns with the propanol concentration > 60%; at lower propanol concentrations, a single short lifetime is observed and in 100% water solutions its value is 0.08 ns. The shorter lifetime, favored in solvent mixtures of higher polarities, is attributed to an exciplex with significant charge‐transfer character. The disappearance of the exciplex emission at low temperatures suggests that the excited state interactions in these dGuo‐C8‐AF adducts at room temperature involve some conformational mobility of the two covalently linked moieties.
SCAVENGING OF SINGLET MOLECULAR OXYGEN BY IMIDAZOLE COMPOUNDS: HIGH and SUSTAINED ACTIVITIES OF CARBOXY TERMINAL HISTIDINE DIPEPTIDES and EXCEPTIONAL ACTIVITY OF IMIDAZOLE‐4‐ACETIC ACID
Authors: Hartman Philip E. , Hartman Zlata , Ault Katherine T.
Published: January 2008

Abstract— Singlet molecular oxygen was generated by illumination of phenosafranin in phosphate buffer at pH 7.5. Relative efficiencies of various imidazole compounds to form endoperoxides were assayed by following at 25°C the rate of light‐ and imidazole‐dependent bleaching of N,N‐dimethyl‐4‐nitrosoaniline. Of over 30 imidazole compounds tested, imidazole‐4‐acetic acid, a major catabolite of histamine in mammals, exhibited the highest activity. l‐Carnosine (β‐alanyl‐l‐histidine), a natural dipeptide prevalent in striated muscle of mammals, possessed several properties important for a physiologically significant scavenger of singlet oxygen. On a molar basis, this readily water‐soluble C‐terminal histidine dipeptide reacted with singlet oxygen two‐to four‐fold faster than free L‐histidine and approximately two‐fold faster than the N‐terminal l‐histidine dipeptides tested. Furthermore scavenging ability of L‐carnosine did not appreciably increase or decrease with time of reaction, in contrast to behaviors exhibited by a number of other imidazole compounds that included some other C‐terminal L‐histidine dipeptides. The fungal metabolite, ergothioneine, blocked singlet oxygen generation by illuminated phenosafranin.
MINIMAL SEQUENCE REQUIREMENTS FOR THE REGULATED EXPRESSION OF rbcS‐A FROM Pisum sativum IN TRANSGENIC TOBACCO PLANTS
Authors: Cuozzo‐Davis Maria , Yong Mun‐Heng , Gilmartin Philip M. , Kuhlemeier Cris , Sarokin Laura , Chua Nam‐Hai
Published: January 2008

Abstract— RbcS‐3A, the most highly expressed member of the pea multigene family encoding the small subunit of ribulose 1,5‐bisphosphate carboxylase, is expressed in a light‐dependent and organ‐specific manner. In order to further delineate the sequences which mediate this complex pattern of regulation, putative regulatory sequences were assayed for function in transgenic tobacco plants in the context of an inactive 5' deleted rbcSSA test gene. We have identified a minimal functional unit of 58 bp which is able to confer organ‐specific transcriptional activity. It contains two sequences conserved among the pea rbcS family members, namely box II (‐151 to ‐138; GTGTGGTTAATATG) and box III (‐125 to ‐114; ATCATTTTCACT). These sequences bind the nuclear factor termed GT‐1 in vitro. Substitution mutations within this 58 bp element have demonstrated that sequences upstream of, or located between, boxes II and III are not required for the transcriptional activity conferred by this element. Distance and orientation of these sequences from the gene are not critical for activity within the limits tested. DNA fragments upstream of nucleotide ‐170 of rbcSSA that contain other GT‐1 binding sites can also confer regulated expression upon the rbcSSA promoter deleted to ‐50. Multimers of individual motifs, namely four tandem copies of boxes II and III, are unable to drive expression of the deleted promoter. These observations suggest that while GT‐1 binding is necessary for promoter activity it is by itself not sufficient.
THE INTERACTIONS OF PYRENYLMETHYL TRIBUTYLPHOSPHONIUM BROMIDE WITH SINGLE STRAND POLYNUCLEOTIDES
Authors: Jones Gareth R. , Oliveira M. Elizabete , Cundall Robert B.
Published: January 2008

Abstract— The binding of the water soluble derivative of pyrene, pyrenylmethyl tri‐n‐butylphos‐phonium bromide (PMTP), to single strand polynucleotides has been characterised by changes in the absorption spectra, fluorescence spectra, the fluorescence lifetime and the time‐resolved fluorescence anisotropy of PMTP. For polyguanylic acid at low ionic strength, there are two modes of binding; external ionic binding and intercalation between the bases. The former results in PMTP excimer formation and the latter involves a charge‐transfer complex between PMTP and guanine bases. Polyadenylic acid and polyinosinic acid show only external binding and poly[C] exhibits an interaction which is a combination of external binding and partial intercalation. Single strand DNA binds PMTP by intercalation and external binding at low ionic strength. In the presence of 0.2 M sodium chloride, only binding by intercalation between the bases occurs for poly[G]. Single strand DNA bound PMPT by partial intercalation, as well as full intercalation between the bases, but polyadenylic acid, polycytidylic acid and polyinosinic acid showed no significant binding in the presence of 0.2 M sodium chloride. The differences in the binding of PMTP are attributed to variations in the rigidity and form the structures of single strand polynucleotides adopt in solution. A full analysis of the binding isotherms has been made using methods based on Scatchard plots and the McGhee and von Hippel approach, which are critically compared.
COMPARATIVE STUDIES ON THE CORRELATION BETWEEN PYRIMIDINE DIMER FORMATION and TYROSINASE ACTIVITY IN CLOUDMAN S91 MELANOMA CELLS AFTER ULTRAVIOLET‐IRRADIATION
Authors: Niggli Hugo J.
Published: January 2008

Abstract— We compared the induction of pyrimidine dimer densities after UV‐irradiation in mouse melanoma cells before and after treatment with cholera toxin. Treatment with cholera toxin stimulated tyrosinase activity up to 50‐fold, leading to a marked, visually apparent increase in cellular melanin concentrations. Irradiation of treated and untreated cells was therefore designed to establish whether intracellular melanin protected cells from UV‐induced DNA damage. In experiments described here, we determined cytosine‐thymine (C‐T) as well as thymine‐thymine dimer levels (T‐T) by high pressure liquid chromatography in cholera toxin‐treated and untreated Cloudman S91 mouse melanoma cells after irradiation with UVC (< 290 ran) and UVB light (290‐320 nm). Surprisingly, induction of melanization had no effect on the formation of pyrimidine dimers by UVC or UVB irradiation. These results indicate that de novo melanin pigmentation induced via the c‐AMP pathway is not involved in protection against UV‐induced thymine‐containing pyrimidine dimers. In separate experiments, irradiation of toxin‐treated and untreated mouse melanoma cells with UVC or UVB light produced a20–30% lower dimer density compared to irradiated human skin fibroblasts. This finding suggests that melanin has some protection properties against UV‐induced pyrimidine dimers, although the exact defense mechanism seems highly complex.
AMERICAN SOCIETY FOR PHOTOBIOLOGY (ASP) HISTORY: 1983–1987
Authors: Jagger John
Published: January 2008

Overall, this pentad (1983‐87) was a time of relative stability. Numbers of papers published in Photochemistry and Photobiology (P&P) was nearly constant (Fig. 1).

Total membership was constant, then rose 13% over the last two years (Table 4). Sustaining membership, however, has tripled in recent years.

Finances showed some disturbing trends. Two of the last three years showed deficits (Table 6), and the Fund Balance was lower in the last two years than in the previous six. Library subscriptions to P&P (a major source of funding for the Society) continued its steady drop of about 12 per year since 1974 (Fig. 3).

These trends suggest that the Society was beginning to grow toward the end of the period, but also becoming less financially sound.

The two major functions of the ASP are to publish P&P and to hold the Annual Meeting. Both of these activities were carried out successfully. During this pentad other activities were also proceeding at a healthy pace. Efforts were made to be more responsive to such public issues as suntan salons, and to have symposia or lectures on environmental problems, such as damage to the stratospheric ozone layer. Efforts were made to advertise the Society more widely, and to encourage photochemical and photobiological publications. A research award and an archives were established. The new format of the Newsletter, its columns on history, and its airing of such issues as the role of ASP in world photo‐biology, added to the effectiveness and the prestige of the Society.
Book Review
Authors: Park Su‐Moon
Published: January 2008

Solar Energy Conversion, A Photoelectrochemical Approach, by Yuri V. Pleskov (translated by Prem Kumar Dang). Springer‐Verlag, Berlin. 1990; 163 pp. DM 178.00.
QUANTUM YIELDS FOR THE CYCLIZATION AND CONFIGURATIONAL ISOMERIZATION OF 4E, 15Z‐BILIRUBIN
Authors: ENNEVER JOHN F. , DRESING THOMAS J.
Published: January 2008

Abstract— Extraction of a solution of bilirubin configurational isomers in chloroform with an aqueous solution of human serum albumin was found to remove selectively the 4Z, 15E‐isomer. This phenomenon was used to develop a method for the purification of the 4E, 15Z‐isomer of bilirubin. The quantum yield for the cyclization and configurational isomerization of the 4E, 15Z‐isomer bound to a molar excess of human serum albumin was measured at 450 and 510 nm. The quantum yield for cyclization to form lumirubin was 0.12 and 0.19 at 450 and 510 nm respectively. The quantum yield for configurational isomerization to form 4Z, 15Z‐bilirubin was 0.03 and 0.05 at 450 and 510 nm. An analysis of previously published data on the quantum yield for the formation of lumirubin from 4Z, 15Z‐bilirubin bound to human serum albumin suggests that all of the formation of lumirubin may occur via consecutive photochemical processes with the 4E, 15Z‐isomer as an intermediate.
FORMATION OF INTRAMOLECULAR EXCIMER IN ARYL PHOSPHATES AND THEIR REACTIVITIES
Authors: Okamoto Yoshiki , Nakamura Mitsunobu , And Min Shi , Takamuku Setsuo
Published: January 2008

Abstract—

The fluorescence spectra of bis(4‐methoxyphenyl) hydrogen phosphate and tris(4‐meth‐oxyphenyl) phosphate showed two emission bands. A longwavelength emission band arose from the intramolecular excimer of two 4‐methoxyphenyl groups and a short band arose from a 4‐methoxyphenyl group itself. There was a good correlation between the relative intensity of the monomer/excimer emissions and the quantum yield of 4,4′‐dimethoxybiphenyl, which was an intramolecular coupling product.
MEMBRANE POTENTIAL CAN INFLUENCE THE RATE OF MEMBRANE PHOTOMODIFICATION
Authors: Valenzeno Dennis Paul , Arriaga Edgar , Trank John , Tarr Merrill
Published: January 2008

Abstract— Though cellular photomodification has been shown to change cellular resting membrane potential, an effect of membrane potential on the rate of photomodification has never been reported. Here we demonstrate that the rate of photomodification of potassium channels in frog atrial cells is voltage dependent. The rate of potassium channel photomodification using negatively charged Rose Bengal as the photosensitizer is about 2.5 times greater at the resting membrane potential of ‐70 m V compared to +40 mV. Similar results are obtained using the positively charged photosensitizer methylene blue. On the other hand, the rate of photomodified increase of leak current in the same cells does not significantly change in this voltage range with Rose Bengal as photosensitizer, but demonstrates a voltage dependence like that of potassium current when methylene blue is the photosensitizer. These observations cannot be explained based on voltage‐dependent partitioning of the sensitizer, as similar effects on potassium current were obtained using either a positively charged or negatively charged sensitizer.
Molecular Mechanism of Photosensitization XI. Membrane Damage and DNA Cleavage Photoinduced by Enoxacin
Authors: Sortino S. , Condorelli G. , De Guidi G. , Giuffrida S.
Published: January 2008

The photosensitizing activity of enoxacin, 1‐ethyl‐6‐fluoro‐1,4‐dihydro‐4‐oxo‐7‐(1‐piperazinyl)‐1,8‐naphthyridine‐3‐carboxilic acid (ENX), toward membranes and DNA has been studied, taking into account human erythrocyte photohemolysis, unilamellar liposome alterations and plasmid pBR322 DNA photocleavage. Hydroxyl radicals and an aromatic carbene generated from ENX photode‐fluorination seem to be the active intermediates involved in the photosensitization process. The steady‐state photolysis products do not participate in the process. The mechanism of photosensitization responsible for the membrane damage depends on the oxygen concentration and follows a different path with respect to that operative for DNA cleavage. Between oxygenated radicals, the hydroxyl seems the species mainly responsible for membrane damage, whereas DNA cleavage is mainly produced by the carbene intermediate. A molecular mechanism of the photosensitization induced by ENX is proposed.
Magnetic Field Effects on the Dynamics of Radical Pairs: The Partition Effect in Vesicles
Authors: Kleinman Mark H. , Shevchenko Tatiana , Bonne Cornelia
Published: January 2008

A combination of product studies and laser flash photolysis (LFP) was used to study the recombination of radical pairs derived from dibenzyl ketone (DBK) and its methyl derivative. Two sizes of vesicles consisting of dioctade‐cyldimethylammonium chloride (DODAC) were generated. In the product studies, irradiation of the ketone led to a substantial overall cage effect both above and below the phase‐transition temperature. However, LFP results demonstrate that no geminate reactions, that correspond to the reactions of radicals generated from the same precursor molecule are occurring even at room temperature. The results are discussed in terms of the partition effect where the cage effect is determined by the differences in the solubility of the radical inside the vesicle bilayer and in the aqueous phase. In small (30 nm diameter) vesicles, most of the random recombination occurs after re‐entry of the radicals into the bilayer, whereas in large (˜150 nm) liposomes, a significant proportion of the recombination reactions takes place in the bulk water. This work demonstrates that magnetic fields can efficiently alter the reactivity of radicals involved in nongeminate pathways and further supports the use of the radical pair mechanism to explain possible effects of magnetic fields in biological systems.
Fluorescence Photobleaching of ALA‐induced Protoporphyrin IX during Photodynamic Therapy of Normal Hairless Mouse Skin: The Effect of Light Dose and Irradiance and the Resulting Biological Effect
Authors: Robinson Dominic J. , de Bruijn Henriëtte S. , van der Veen Nynke , Stringer Mark R. , Brown Stanley B. , Star Willem M.
Published: January 2008

The photobleaching of 5‐aminolaevulinic acid (ALA)‐induced protoporphyrin IX (PpIX) was investigated during superficial photodynamic therapy (PDT) in normal skin of the SKH HRt hairless mouse. The effects of light dose and fluence rate on the dynamics and magnitude of photobleaching and on the corresponding PDT‐induced dam‐age were examined. The results show that the PDT damage cannot be predicted by the total light dose. Photo‐bleaching was monitored over a wide range of initial PpIX fluorescence intensities. The rate of PpIX photo‐bleaching is not a simple function of fluence rate but is dependent on the initial concentration of sensitizer. Also, at high fluence rates (50–150 mW/cm2, 514 nm) oxygen depletion is shown to have a significant effect. The rate of photobleaching with respect to light dose and the corresponding PDT damage both increase with decreasing fluence rate. We therefore suggest that the definition of a bleaching dose as the light dose that causes a 1/e reduction in fluorescence signal is insufficient to describe the dynamics of photobleaching and PDT‐induced dam‐age. We have detected the formation of PpIX photoproducts during the initial period of irradiation that were themselves subsequently photobleached. In the absence of oxygen, PpIX and its photoproducts are not photo‐bleached. We present a method of calculating a therapeutic dose delivered during superficial PDT that demonstrates a strong correlation with PDT damage.
Significance of Dosimetry in Photodynamic Therapy of Injured Arteries: Classification of Biological Responses
Authors: Adili Farzin , van Eps Randolph G. Statius , LaMuraglia Glenn M.
Published: January 2008

With conflicting results in the literature on the ability of photodynamic therapy (PDT) to inhibit intimal hyperplasia (IH), the present study systematically investigated the effects of drug and light dosimetry on the biologic responses in the artery wall. The rat common carotid artery was balloon‐injured and pressurized with benzopor‐phyrin‐derivative monoacid ring (BPD). Then, PDT was performed with an external laser at different fluences and the biologic responses of the artery wall were histologically examined at 24 h and at 2 weeks. Photodynamic therapy effects on injured arteries can be classified into four stages: low‐dose PDT using 0.5 (ig/mL BPD at 50 J/cm2(stage I) resulted in incomplete cell eradication and significant IH at 2 weeks. Irradiation with 100 J/cm2at the same BPD concentration (stage II) completely eradicated the cells in the artery wall at 24 h but still led to IH at 2 weeks. However, 25 (tg/mL BPD at 100 J/cm2(stage in) resulted in total cell eradication at 24 h and inhibition of IH at 2 weeks. In contrast, high‐dose PDT with 25 μg/mL BPD and 200 J/cm2(stage TV) led to thrombus development and vascular occlusion at 24 h. These data, demonstrating the different stages of PDT effects on injured arteries, emphasize the critical importance of appropriate PDT dosimetry for the effective inhibition of IH.
Stepwise Solid‐Phase Synthesis of Nucleopeptides
Authors: Grandas Anna , Marchán Vicente , Debéthune Laurent , Pedroso Enrique
Published: January 2008

Phosphodiester‐linked peptide‐oligonucleotide conjugates (nucleopeptides) are obtained by stepwise solid‐phase procedures. The peptide is first assembled on a suitably derivatized solid matrix and the oligonucleotide is subsequently elongated at the free hydroxyl group of the linking amino acid. Temporary acid‐labile and permanent base‐labile protecting groups are combined. Careful choice of the protection scheme is required to prevent and minimize side reactions that may degrade the target molecule. Curr. Protoc. Nucleic Acid Chem. 31:4.22.1‐4.22.54. © 2007 by John Wiley & Sons, Inc.
Heck reactions in monoglyme and diglyme using BmimCl as pre‐ligand
Authors: da Silva Aline A. Bello , de Souza Andréa Luzia F. , Antunes O. A. C.
Published: January 2008

Heck reactions between iodobenzene and methyl acrylate were carried out in monoglyme and diglyme as solvents, using different ligands and palladium sources, and good to high yields were obtained in the production of (E)‐substituted olefins. The ionic liquid BmimCl was successfully utilized as pre‐ligand to substitute triphenylphosphine. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis, electrochemical properties and fungicidal activity of 1,1′‐bis(aroyl)ferrocenes and their derivatives
Authors: Dou Yan‐Ye , Xie Yun‐Fu , Tang Liang‐Fu
Published: January 2008

Reaction of functionalized cyclopentadienyl sodium CH3O2CArC(O)CpNa (Ar = aryl and Cp = cyclopentadienyl) with FeCl2 in a 2:1 ratio gives 1,1′‐bis(aroyl)ferrocenes [CH3O2CArC(O)Cp]2Fe in reasonable yields. Upon treatment of these aroyl compounds with NaBH4, the ketone carbonyl is reduced to yield compounds [CH3O2CArCH(OH)Cp]2Fe, while with the stronger reductive reagent LiAlH4, diols [HOCH2ArCH(OH)Cp]2Fe are obtained. All new compounds were characterized by IR and NMR spectroscopic analyses. Their electrochemical behavior was investigated by cyclic voltammetry. The structure of [CH3O2CC10H6C(O)Cp]2Fe was further confirmed by single crystal X‐ray diffraction analysis. In addition, the fungicidal activities of these new compounds were also determined in vitro. Copyright © 2007 John Wiley & Sons, Ltd.
Decolorization of reactive dyebath containing high exhaust and low salt dyes by nanofiltration and its reuse
Authors: Vishnu G. , Joseph Kurian
Published: January 2008

Nanofiltration (NF) is a relatively new field in membrane technology, which has the potential to be the front‐runner in management of reactive dyeing effluents with respect to removal of color to enable reuse of salt. This paper discusses the performance of NF‐270‐2540 FILMTEC NF membrane for color removal and salt recovery from exhausted reactive dyebaths. Simulated dyebaths containing high exhaust (CI Red 120, CI Yellow 84 and CI Blue 4) and low salt (Cibacron Red LS6G, Yellow LSR, Blue LSG) reactive dyes were prepared for light, medium, and dark shades. The dye retention decreased at high salt concentrations of 60 and 90 g/L. The chemical oxygen demand (COD) and total organic carbon removal efficiency was in the range of 80–90%. The permeate flux significantly decreased beyond a salt concentration of 40 g/L. The reusability studies on the recovered permeate showed that it could be reused for light, medium, and dark shades. © 2008 American Institute of Chemical Engineers Environ Prog, 2008
Differences in gene expression and benzo[a]pyrene‐induced DNA adduct formation in the liver of three strains of female mice with identical AhRb2 genotype treated with 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin and/or benzo[a]pyrene
Authors: Wu Qing , Suzuki Junko S. , Zaha Hiroko , Lin Tien‐Min , Peterson Richard E. , Tohyama Chiharu , Ohsako Seiichiroh
Published: January 2008

To search for genes whose products modify aryl hydrocarbon receptor (AhR)‐dependent toxicity caused by 2,3,7,8‐tetrachlorodibenzo‐p‐dioxin (TCDD), gene expression profiles in the liver were surveyed using microarrays 24 h after the administration of TCDD to three strains of female mice, BALB/cAnN (BALB), C3H/HeN (C3H) and CBA/JN (CBA) all of identical AhR genotype. The BALB/cAnN strain had a more marked induction of a number of glutathione S‐transferase (GST) sub‐families, particularly the GSTmu gene family, compared with the other two strains. To assess the effects of GSTs induction to metabolize carcinogens, TCDD (40 µg kg−1) was administered to BALB and CBA strains, followed 24 h later by an i.p. injection of low or high dose of benzo[a]pyrene (B[a]P, 50 or 200 mg kg−1). The 32P‐postlabelling analysis showed that administration of TCDD alone failed to induce DNA adduct formation in both BALB and CBA strain mouse livers. The low dose of B[a]P alone produced DNA adduct in the liver of both strains to a similar extent. Treatment with TCDD 24 h before the low dose of B[a]P suppressed the formation of B[a]P‐induced DNA‐adduct more markedly in the BALB strain compared with the CBA strain. Taken together, these findings show that TCDD treatment causes strain‐specific alterations in gene expression and B[a]P‐induced DNA adduct formation in the liver of female mice of the same AhRb2 genotype. Furthermore, it suggests that TCDD‐treated female mice of the BALB strain may have genes whose products modify the toxicity of B[a]P as evidenced by TCDD‐induced alterations in B[a]P‐DNA adduct formation. Copyright © 2008 John Wiley & Sons, Ltd.
Gender and collective action: motivations, effectiveness and impact
Authors: Pandolfelli Lauren , Meinzen‐Dick Ruth , Dohrn Stephan
Published: January 2008

Gender is often a key determinant of people's abilities to participate in collective action, yet there has been relatively little research on the links between gender and collective action. This article, and the ones that follow in this special issue, explore the intersection of these two fields. We present three entry points for a gendered analysis of collective action: motivations to engage in collective action; effectiveness of collective action (as defined by group objectives and the process by which the group works to meet those objectives); and impact of collective action on gender equity. We discuss each of these themes by highlighting key issues presented in the articles in this special issue. Copyright © 2008 John Wiley & Sons, Ltd.
Reconstructing small perturbations of scatterers from electric or acoustic far‐field measurements
Authors: Lim Mikyoung , Louati Kaouthar , Zribi Habib
Published: January 2008

In this paper, we consider the problem of determining the boundary perturbations of an object from far‐field electric or acoustic measurements. Assuming that the unknown scatterer boundary is a small perturbation of a circle, we develop a linearized relationship between the far‐field data and the shape of the object. This relationship is used to find the Fourier coefficients of the perturbation of the shape. Copyright © 2008 John Wiley & Sons, Ltd.
Monensin controlled-release capsules for methane mitigation in pasture-fed dairy cows
Authors: Waghorn G. C. , Clark H. , Taufa V. , Cavanagh A.
Published: January 2008

This experiment was undertaken to evaluate controlled-release capsules (CRC) that released monensin, for the mitigation of methane production from cows. The evaluation has been bought about by government policies to lower agricultural greenhouse gas (GHG) emissions, whilst maintaining profitability of dairy farms in New Zealand. The experiment used 60 Friesian–Holstein cows fed ryegrass (Lolium perenne L.)-dominant pasture, starting in week 7 of lactation. The CRC were placed in the rumen of 30 cows and effects of monensin on milk production were measured over 11 weeks by comparison with 30 control cows (Con). Cows were grazed as a single herd for the majority of the trial, but 32 (16 CRC, 16 Con) were fed indoors for 36 days (four 9-day periods) for measurement of intakes and methane. Monensin CRC did not affect methane production, which averaged 19.7 g/kg dry matter intake (DMI). There were also no significant treatment effects on DMI (16.5 kg DM/day) and milk production (21.3 kg/day) when measured indoors or on milk production over the whole experiment (21.7 kg/day). Ruminal metabolites measured from five rumen-fistulated cows in either group were not significantly different. At the conclusion of the experiment, monensin release rate from the CRC (10.8 mg/kg DMI) retrieved from five fistulated cows averaged 52% of anticipated values. Inadequate performance of the controlled delivery device prevented an unequivocal evaluation of the monensin CRC for methane mitigation in dairy cows fed pasture.
Loss of talin1 in platelets abrogates integrin activation, platelet aggregation, and thrombus formation in vitro and in vivo
Authors: Nieswandt Bernhard , Moser Markus , Pleines Irina , Varga-Szabo David , Monkley Sue , Critchley David , Fässler Reinhard
Published: January 2008

Platelet adhesion and aggregation at sites of vascular injury are essential for normal hemostasis but may also lead to pathological thrombus formation, causing diseases such as myocardial infarction or stroke. Heterodimeric receptors of the integrin family play a central role in the adhesion and aggregation of platelets. In resting platelets, integrins exhibit a low affinity state for their ligands, and they shift to a high affinity state at sites of vascular injury. It has been proposed that direct binding of the cytoskeletal protein talin1 to the cytoplasmic domain of the integrin β subunits is necessary and sufficient to trigger the activation of integrins to this high affinity state, but direct in vivo evidence in support of this hypothesis is still lacking. Here, we show that platelets from mice lacking talin1 are unable to activate integrins in response to all known major platelet agonists while other cellular functions are still preserved. As a consequence, mice with talin-deficient platelets display a severe hemostatic defect and are completely resistant to arterial thrombosis. Collectively, these experiments demonstrate that talin is required for inside-out activation of platelet integrins in hemostasis and thrombosis.
Preparation and Loading of Gelatin Nanoparticles
Authors: Kommareddy Sushma , Amiji Mansoor M.
Published: January 2008

INTRODUCTION

This protocol describes the synthesis of nanoparticles using the biopolymer gelatin and its derivatives, the loading of DNA to the nanoparticles by encapsulation and adsorption, and the estimation of entrapment efficiency. The steps involved in the preparation of nanoparticles by desolvation using ethanol are presented, as are the precautions to be taken during the encapsulation or adsorption of the payload.
Two new genera of Eucoilidae (Hymenoptera: Cynipoidea)
Authors: QUINLAN J.
Published: January 2008

Psichacra marshalli Cameron is redescribed and assigned to the new genus Pseudopsichacra. ‘New Genus B’ of Weld is redescribed as Bewelda gen.n. and striata sp.n. is designated as the type–species. An emendation of Weld's key is included to show the positions of both genera.
The immature stages of some Phlebotomine sandflies from Brazil (Diptera: Psychodidae)
Authors: WARD RICHARD D.
Published: January 2008

Immature stages of Lutzomyia anduzei (Rozeboom), L.antunesi (Coutinho), L. flaviscutellata (Mangabeira), Psychodopygus davisi (Root), Ps.paraensis (Costa Lima) and Ps.lainsoni Fraiha & Ward are described from specimens reared in the laboratory. The Lutzomyia species are members of the intermedia group, though L. flaviscutellata larvae more closely resemble those of Psychodopygus species. The larvae of L.anduzei and L. antunesi are separable on minor setal differences and are similar to previously described members of the intermedia group. Ps. paraensis is distinguishable from the other two Psychodopygus species described, by the absence of prothoracic seta 2. Head seta 5 of Ps.davisi is about twice the length of that in Ps. paraensis and larvae of Ps.lainsoni are pale and characterized by colourless body setae 4 and 10. A key to the fourth instar larvae is given which includes all the known larvae of the intermedia group and of the genus Psychodopygus. Morphological differences in the Psychodopygus larvae do not appear to reflect the separation of the adults into series.
Coganomyia ornata sp. n. (Diptera: Calliphoridae): a spectacular new fly from Angola
Authors: DEAR J. P.
Published: January 2008

Abstract. Coganomyia ornata gen. et sp.n. is described from Angola, and a possible second species from Uganda is reported. This genus resembles Auchmeromyia (Calliphoridae) in the presence of long, curved and fused male cerci, although there are five rather than four visible abdominal tergites.
A revision of the neotropical genus Vilga Stål (Hemiptera: Coreidae)
Authors: DOLLING W. R.
Published: January 2008

Abstract. Thirteen species of the genus Vilga Stål are recognized and described or redescribed and a key for their identification is given. Lectotypes are designated for Centrocoris westwoodi Kolenati, Vilga dissimilis Distant, Vilga spinosula Montandon, Vilga mexicana Distant, Vilga penningtoni Bergroth and Vilga dallasi Distant. The new combination Vilga chilensis (Stein) is established for Arenocoris chilensis Stein. The new synonymy Vilga dissimilis Distant (=Vilga spinosula Montandon) is established. The new species Vilga brasiliensis (from Brazil), V.grisea (Brazil), V.grisescens (Brazil), V.obliqua (Brazil), V.peruviana (Peru) and V.sanctipauli (Brazil) are described. The genus Vilga is divided into six subgenera, the five new subgeneric names being Vilgula (type‐species: Vilga dissimilis Distant), Trichovilga (type‐species: Vilga mexicana Distant), Platyvilga (type‐species: Arenocoris chilensis Stein), Laevivilga (type‐species: Vilga divaricata Distant) and Echinovilga (type‐species: Vilga dallasi Distant).
The occurrence of Almeidini (Hemiptera: Anthocoridae) in Australia, with the description of a new genus
Authors: WOODWARD T. E.
Published: January 2008

Abstract. The tribe Almeidini Carayon, 1972 is recorded from Australia and Australmeida gen.n. described. The brachypterous male and female of the typespecies Lasiochilus derricki Gross, 1954 are redescribed and the macropterous male and female and the submacropterous female are newly described. One possibly conspecific specimen is recorded from Kerevat, New Britain. The structure of the male and female internal reproductive systems reinforces the external characters used by Carayon (1972a) as indicating close affinity of the Almeidini to the Xylocorini. The genus Almeida Distant is recorded from Australia and the genuse Limppomanus Distant from New caledonia.
Pronophiline butterflies (Satyridae) of the Sierra Nevada de Santa Marta, Colombia
Authors: ADAMS M. J. , BERNARD G. I.
Published: January 2008

Abstract.The twenty‐four species of Pronophilini known from the Sierra Nevada de Santa Marta, a small, isolated and very high north Colombian mountain range, are listed. The ecology of the tribe in northern South America, where these butterflies are exclusively montane, is described. The evolutionary relationships of the thirteen endemic species are analysed. Three new genera, three new species, and four new subspecies are described. Four new synonymies are established, the status of three taxa revised, six new combinations made, lished, the status of three taxa and one original combination re‐instated.
A morphometric comparison of three closely related species of Myrmica (Formicidae), including a new species from England
Authors: ELMES G. W.
Published: January 2008

In the course of a population study on Myrmica sabuleti Meinert a miniature queen was found in some colonies. This paper describes the form as a new parasitic species, Myrmica hirsuta sp.n., and shows how an analogous male was identified. Twelve measurements were then made on a sample of males and females of this new species and these were compared with M. sabuleti and Myrmica scabrinodis Nyl. using a multivariate discriminating technique. The status of the new species is discussed.
A new tribe, Epistomentini, of Buprestidae (Coleoptera) with a redefinition of the tribe Chrysochroini
Authors: LEVEY B.
Published: January 2008

A new tribe Epistomentini is designated to include Epistomentis Solier, Cyria Solier (with which Cyrioides Carter and Xenocyria Obenberger are synonymized), Diadoxus Thomson, Cyrioxus Hoschek, and a new genus and species Araucariana queenslandica, which is described.

The tribe Chrysochroini is redefined, and Epidelus Deyrolle, Cyalithus Thomson, Cyalithoides Fisher and Chrysopistus Thery are transferred to it from the Chalcophorini. Chalcophoropsis Thomson is transferred from the Chrysochroini to the Chalcophorini.

A reassessment of the value of some characters used in the higher classification of the Buprestidae is given.
The phylogeny of some Papilio species based on interspecific hybridization data
Authors: AE SHIGERU A.
Published: January 2008

Abstract. Adults of different species of the genus Papilio can easily be mated by hand‐pairing. The data on egg hatchability, adult formation and F1 fertility in these interspecific hybrids show notable variations according to the crosses. Using these data, values of a differentiation index for each cross were calculated. These estimates of genetic distance were then used to study the phylo‐genetic relationships of the species involved. The data are consistent with the existence of the following groups, each consisting of closely related species: the black Papilio supergroup, the Papilio memnon group, the P.demoleus group, the P.xuthus group, the P.machaon group, the P.bianor group, the P.glaucus group and the P.troilus group. The phylogenetic relationships revealed by these data generally coincide with the relationships established by classical taxonomy. In cases where there are differences of opinion among taxonomists, the writer's data usually support one or other of them.
Configuration of the digestive tube as an aid to identification of worker Termitidae (Isoptera)
Authors: JOHNSON R. A.
Published: January 2008

Abstract. The appearance of the digestive tube in situ is shown to be valuable in the identification of worker termites, particularly those of detritus and soil feeding species. Genera, and sometimes species, can be identified by this character. These preliminary findings will be of assistance to termite ecologists interested in population studies, where problems of the identification of mixed samples containing workers from cores or other soil samples are a serious problem.
Laboratory evidence showing the separate species status of Schistocerca gregaria, americana and cancellata (Acrididae, Crytacanthacridinae)
Authors: JAGO N. D. , ANTONIOU A. , SCOTT P.
Published: January 2008

Abstract. Results are given of experimental crosses of Schistocerca species from the New World and the Old World Desert Locust. It is concluded that S. cancellata (Serville), S. gregaria (Forskal) and S. americana (Drury) are separate species in their own right not subspecies of americana. The African Desert Locust should thus be called S. gregaria gregaria and its S. W. African race S. gregaria flaviventris (Burmeister). The name S. vicaria (Walker) is proposed for the Central American Locust. The relationship of S. paranensis to Sxancellata is discussed.