Action Spectrum for the Photophobic Response of Ciona intestinalis (Ascidieacea, Urochordata) Larvae Implicates Retinal Protein

Ascidian tadpole larvae change swimming behavior during the course of development. The photic behavior of the larvae of Ciona intestinalis was monitored by a computerized cell-tracking system with a time resolution of 0.1 s. Newly hatched larvae swim at an average speed of 1.4 mm/s but show no response to light stimuli. The swimming speed of the larvae became slower (0.4 mm/s) 3 h after hatching and they were induced to swim more rapidly by a sudden decrease in light intensity 4 h after hatching. During the course of development, the maximal speed of swimming behavior increased with time until 8 h after hatching and then plateaued. The action spectrum for the step-down photophobic response of the larvae was determined at around 8 h after hatching and was fitted to Dartnall's nomogram with the absorbance maximum of the pigment located at 505 nm. These results suggest retinal proteins in the ocellus of the larvae are the photoreceptors for the photobehavior.     

Distinguishing Activities in the Photodynamic Arsenals of the Pigmented Ciliates Blepharisma sinuosum Sawaya, 1940 and Blepharisma japonicum Suzuki, 1954 (Ciliophora: Heterotrichea)

Blepharismins are photodynamic hypericin-like dianthrones produced as a variable pigment blend in Blepharisma ciliates and mostly studied in the Afro-Asiatic Blepharisma japonicum. The present work describes the bioactivity of pigments from the Brazilian Blepharisma sinuosum. Comparative analyses showed that the pigments from both species can trigger photo-induced modifications in phospholipids, but different redox properties and biological activities were assigned for each pigment blend. Stronger activities were detected for B. sinuosum pigments, with the lethal concentration LC₅₀ 10 × lower than B. japonicum pigments in light-irradiated tests against Bacillus cereus and less than half for treatments on the human HeLa tumor cells. HPLC showed B. sinuosum producing a simpler pigment blend, mostly with the blepharismin-C (~ 70%) and blepharismin-E (~ 30%) types. Each blepharismin engaged a specific dose–response profile on sensitive cells. The blepharismin-B and blepharismin-C were the most toxic pigments, showing LC₅₀ ~ 2.5–3.0 µm and ~ 100 µm on B. cereus and HeLa cells, respectively, after illumination. Similarity clustering analysis compiling the bioactivity data revealed two groups of blepharismins: the most active, B and C, and the less active, A, D and E. The B. sinuosum pigment blend includes one representative of each clade. Functional and medical implications are discussed.     

Immunochemical analysis of a photoreceptor protein using anti-IP3 receptor antibody in the unicellular organism, Blepharisma

The blepharismin-200 kD protein complex of the ciliated protozoan Blepharisma is a novel type of photosensor responsible for the step-up photophobic response of the cell. In immunoblotting assays, the 200 kD protein is weakly cross-reacted with anti-inositol triphosphate receptor antibody (anti-IP3 R antibody). Indirect immunofluorescence assays show that the pigment granules in which the blepharismin-200 kD protein complex is localized are labelled by anti-IP3 R antibody. When the anti-IP3 R antibody or antisense oligonucleotide for IP3 receptor is introduced into the living cells of Blepharisma, both the photosensitivity of the cells and content of blepharismin-200 kD protein are reduced. The results suggest that the photoreceptor 200 kD protein is possibly an IP3 receptor-like protein.     

Fringelite D, a Model of the Protist Photosensory Pigments of the Stentorinand Blepharismin Types: The Hypericinand Fringelite D PhotosensitizedDestruction of Bilirubin

 Using the hypericin and fringelite D photosensitized destruction of bilirubin together with fluorescence spectroscopy it was found that in contrast to fringelite D hypericin behaves as an effective photodynamic agent producing mainly singlet oxygen. This makes fringelite D and concomitantly the related stentorin and blepharismin pigments better suited for the photosensory transduction chain where, as shown recently, an initial proton expulsion reaction plays the fundamental role. Thus, in organisms using these photosensory pigments the production of deleterious oxygen species becomes diminished as compared to hypericin. In addition it was found that complexation with albumin further inhibits bilirubin destruction.     

Molecular Identification of the Transient Species Mediating the Deactivation Dynamics of Solvated Guanosine and Deazaguanosine

Small structural alterations of the purine/pyrimidine core have been related to important photophysical changes, such as the loss of photostability. Similarly to canonical nucleobases, solute-solvent interactions can lead to a change in the excited state lifetimes and/or to the interplay of different states in the photophysics of these modified nucleobases. To shed light on both effects, we here report a complete picture of the absorption spectra and excited state deactivation of deoxyguanosine and its closely related derivative, deoxydeazaguanosine, in water and methanol through the mapping of the excited state potential energy surfaces and molecular dynamics simulations at the TD-DFT level of theory. We show that the N by CH exchange in the imidazole ring of deoxyguanosine translates into a small red-shift of the bright states and slightly faster dynamics. In contrast, changing solvent from water to methanol implies the opposite, i.e., that the deactivation of both systems to the ground state is significantly hindered.     

Fringelite D, a Model of the Protist Photosensory Pigments of the Stentorinand Blepharismin Types: The Hypericinand Fringelite D PhotosensitizedDestruction of Bilirubin

Summary.  Using the hypericin and fringelite D photosensitized destruction of bilirubin together with fluorescence spectroscopy it was found that in contrast to fringelite D hypericin behaves as an effective photodynamic agent producing mainly singlet oxygen. This makes fringelite D and concomitantly the related stentorin and blepharismin pigments better suited for the photosensory transduction chain where, as shown recently, an initial proton expulsion reaction plays the fundamental role. Thus, in organisms using these photosensory pigments the production of deleterious oxygen species becomes diminished as compared to hypericin. In addition it was found that complexation with albumin further inhibits bilirubin destruction. Received June 29, 2000. Accepted July 18, 2000     

Coralloidolide A and Coralloidolide B,the First Cembranoids from a Mediterranean Organism,the Alcyonacean Alcyonium coralloides

The alcyonacean Alcyonium ( = Parerythropodium) coralloides (PALLAS 1766) is the first Mediterranean organism shown to contain cembranoids. These are of unusual type like coralloidolide A ( = (?)-(1R*, 2R*, 3R*, 12S*, 5Z, 7Z, 9Z)-1, 2:7, 10-diepoxy-12-isopropenyl-5, 9-dimethylcyclotetradeca-5, 7, 9-triene-1, 3-carbolactone; (?)-6) and coralloidolide B ( =(?)-(1R*,2S*,3R*,7S*,10S*,12S*,5Z,8Z,)-2, 7:7, 10-diepoxy-1, 10-dihydroxy-12-isopropenyl-5, 9-dimethylcyclotetradeca-5,8-diene-1,3-carbolactone; (?)-8). Structural assignments are mainly based on 1D- and 2D-NMR data and on chemical transformations.     

一种新型多吡啶钌配合物的合成及其太阳光谱响应特性

以二茂铁和2-吡啶甲酰胺为原料,经偶联、氧化、溴乙酰化及环合反应制备了一种新型的二茂铁噻唑衍生物4-二茂铁-2-(2-吡啶)基噻唑(2-FPT);以2-FPT为第一配体,2,2'-联吡啶-4,4'-二甲酸(dcbpy)为第二配体,与二异苯丙基氯化钌进行配位,合成了一种新型的光敏化染料Ru(dcbpy)2(2-FPT)(...     

大蒜油环糊精包合物的制备

制备并鉴定温江大蒜油环糊精包合物。以大蒜油的平均利用率和包合物产率为指标,通过正交实验考查大蒜油与环糊精的投料比、包合温度、包合时间对包合工艺的影响,得出最佳包合工艺:投料比1∶8、包合温度60℃、包合时间2 h,此时挥发油的平均利用率为62.3%,包合物收率为72.1%。使用薄层色谱法对包合物进行鉴定,结果显示大蒜油与环糊精包合后,没有显示与大蒜油有相同的斑点,而大蒜油与环糊精的混合物有相同斑点。     

IR与ESI/MS结合鉴定复杂表面活性剂结构

复杂表面活性剂的结构鉴定往往是比较困难的，尤其在有许多副产物共存时，尝试应用红外光谱、质谱以及电喷雾质谱相结合的方法鉴定复杂表面活性剂及其副产物的结构。     

Algal-Derived Synthesis of Silver Nanoparticles Using the Unicellular ulvophyte sp. MBIC10591: Optimisation,Characterisation, and Biological Activities

Algal-mediated synthesis of nanoparticles (NPs) is an eco-friendly alternative for producing NPs with potent physicochemical and biological properties. Microalgae represent an ideal bio-nanofactory because they contain several biomolecules acting as passivation and stabilising agents during the biogenesis of NPs. Herein, a novel microalgae sp. was isolated, purified, and identified using light and electron microscopy and 18s rRNA sequencing. The chemical components of their watery extract were assessed using GC-MS. Their dried biomass was used to synthesise silver (Ag) NPs with different optimisation parameters. Ag-NPs were physiochemically characterised, and their anticancer and antibacterial effects were examined. The data showed that the isolated strain was 99% similar to the unicellular ulvophyte sp. MBIC10591; it was ellipsoidal to spherical and had a large cup-shaped spongiomorph chloroplast. The optimum parameters for synthesising Ag-NPs by unicellular ulvophyte sp. MBIC10591 (Uv@Ag-NPs) were as follows: mixture of 1 mM of AgNO₃ with an equal volume of algal extract, 100 °C for 1 h, and pH of 7 under illumination for 24 h. TEM, HRTEM, and SEM revealed that Uv@Ag-NPs are cubic to spherical, with an average nanosize of 12.1 ± 1.2 nm. EDx and mapping analysis showed that the sample had 79% of Ag, while FTIR revealed the existence of several functional groups on the NP surface derivatives from the algal extract. The Uv@Ag-NPs had a hydrodynamic diameter of 178.1 nm and a potential charge of −26.7 mV and showed marked antiproliferative activity against PC3, MDA-MB-231, T47D, and MCF-7, with IC₅₀ values of 27.4, 20.3, 23.8, and 40 µg/mL, respectively, and moderate toxicity against HFs (IC₅₀ of 13.3 µg/mL). Uv@Ag-NPs also showed marked biocidal activity against Gram-negative bacteria. Escherichia coli was the most sensitive bacteria to the NPs with an inhibition zone of 18.9 ± 0.03 mm. The current study reports, for the first time, the morphological appearance of the novel unicellular ulvophyte sp., MBIC10591, and its chemical composition and potential to synthesise Uv@Ag-NPs with smaller sizes and high stability to act as anti-tumour and microbial agents.     

Development of a Water-Dispersible Supramolecular Complex of Polyphenol with Polypeptides for Attenuation of the Allergic Response using a Mechanochemical Strategy

The prevalence of allergic disorders has increased worldwide in recent decades. Polyphenols, including resveratrol and curcumin, are posited to have potential as therapeutic agents for allergy; however, their use has been limited by poor water solubility. Accordingly, a highly concentrated, water dispersible, supramolecular complexes of polyphenols with polypeptides (poly-L-lysine, poly-γ-glutamic acid) and gelatin using high-speed vibration milling are developed. The complex exhibits resistance to photobleaching and thermal radiation. Treatment of a rat basophilic leukemia cell line (RBL-2H3) with polypeptide complexes containing resveratrol is suppressed allergic responses in vitro. Moreover, aerosolized administration of polypeptide complexes demonstrates excellent bioavailability and inhibition of immediate hypersensitivity reactions in ear tissue in vivo. Furthermore, the method avoids the use of organic solvent and therefore reduces undesirable biological responses.     

纳米脂质体复合物-包封多酸化合物的合成,表征和生物活性研究

The polyoxometalate K6H[CoW11O39（CpTi）] （abbreviated as CoW11CpTi, Cp=η^5-C5H5） loaded nanosize-liposome complex has been prepared and structurally characterized by elemental analysis, IR and UV spectra. The particle size of the complex was distributed in the range of 100-250 nm with the average diameter of 132.6 nm. The result showed that the polyoxometalate retained the parent structure after being encapsulated by liposome and liposomal encapsulation increased the antitumoral activity of the polyoxometalate.     

Localization and Spread of the Particle in a Box

The most basic example of a quantum mechanical problem, the one-dimensional particle in a box, is revisited. Three aspects are treated. 1. It is shown that a number of textbooks give an incorrect result for the expectation value of x², and, therefore, do not obtain the correct spread x. Consequently, the verification of the Heisenberg relation is also in error. 2. It is found that textbooks do not mention the origin dependence of expectation values, which is a nuisance, as the problem is evidently treated in the literature with two choices of origin. 3. Superposition of an infinite number of even (cosine) solutions of the one-dimensional particle in the box allows for an analytical demonstration of complete localization of the particle (x = 0).     

Target Identification of 22-(4-Pyridinecarbonyl) Jorunnamycin A,a Tetrahydroisoquinoline Derivative from the Sponge Xestospongia sp., in Mediating Non-Small-Cell Lung Cancer Cell Apoptosis

A dysregulation of the cell-death mechanism contributes to poor prognosis in lung cancer. New potent chemotherapeutic agents targeting apoptosis-deregulating molecules have been discovered. In this study, 22-(4-pyridinecarbonyl) jorunnamycin A (22-(4′py)-JA), a synthetic derivative of bistetrahydroisoquinolinequinone from the Thai blue sponge, was semisynthesized by the Steglich esterification method, and its pharmacological mechanism in non-small-cell lung cancer (NSCLC) was elucidated by a network pharmacology approach. All predicted targets of 22-(4′py)-JA and genes related to NSCLC were retrieved from drug-target and gene databases. A total of 78 core targets were identified, and their associations were analyzed by STRING and Cytoscape. Gene ontology and KEGG pathway enrichment analyses revealed that molecules in mitogen-activated protein kinase (MAPK) signaling were potential targets of 22-(4′py)-JA in the induction of NSCLC apoptosis. In silico molecular docking analysis displayed a possible interaction of ERK1/2 and MEK1 with 22-(4′py)-JA. In vitro anticancer activity showed that 22-(4′py)-JA has strong cytotoxic and apoptosis-inducing effects in H460, H292 and A549 NSCLC cells. Furthermore, immunoblotting confirmed that 22-(4′py)-JA induced apoptotic cell death in an ERK/MEK/Bcl-2-dependent manner. The present study demonstrated that 22-(4′py)-JA exhibited a potent anticancer effect that could be further developed for clinical application and showed that network pharmacology approaches are a powerful tool to illustrate the molecular pathways of new drugs or compounds.     

一个双双核铜配合物的合成、结构及表征

Studies on the complexes containing formate have never been stopped for a half century. In this paper, a new copper(Ⅱ) complex, [Cu₂(phen)₂(HCOO)₂( μ-OH)₂][Cu₂(phen)₂(H₂O)₂(μ-OH)₂](HCOO)₂·10H₂O (1) (phen=1,10-phenanthroline), has been synthesized and characterized by elemental analysis, IR, and X-ray diffraction single crystal structure analysis. It belongs to triclinic system, with space group P1, a=1.151 7(3) nm, b=1.162 6(3) nm, c=1.216 0(3) nm, α=74.672(4)°, β=67.291(4)°, γ=79.029(4)°, V=1.441 4(6) nm³. The four copper(Ⅱ) ions in the complex are all 5-coordinated and exhibit a distorted square pyramidal coordination environment. The molecule are connected by intermolecular hydrogen bonds (C-H…O) interactions and π-π stacking, resulting in a three-dimensional network. CCDC: 648152.     

Light-induced Damage in the Retina: Differential Effects of Dimethylthiourea on Photoreceptor Survival, Apoptosis and DNA Oxidation

In the rat, photoreceptor cell death from exposure to intense visible light can be prevented by prior treatment with antioxidants. In this study we subjected albino rats raised in dim cyclic light and rats made more susceptible to light damage by rearing in darkness to exposures of green light that led to similar losses of photoreceptor cells. Rhodopsin and photoreceptor DNA, indicators of the number of surviving photoreceptor cells, were determined at various times over a period of 14 days after light exposure. Fragmentation of DNA was determined over a similar time course by neutral and alkaline agarose gel electrophoresis. Apoptosis in retinal DNA was measured by quantitating the appearance of 180 base pair (bp) nucleosomal fragments. Oxidation of DNA was measured by electrochemical detection of the nucleoside 8-hydroxydeoxyguanosine (8-OHdG) after separation by high-performance chromatography. For albino rats reared in dim cyclic light, 24 h of intense light exposure resulted in the loss of 50% rhodopsin and photoreceptor cell DNA. In dark-reared rats, the losses were 40%, respectively, after only 3 h of intense light treatment. In both cases pretreatment with the antioxidant dimethylthiourea (DMTU) prevented rhodopsin and photoreceptor cell DNA loss. The kinetics of the light-induced apoptosis depended markedly on the rearing environment of the rats. The DNA ladders appeared within 12 h of the onset of intense light in the rats reared in dim cyclic light. In these rats the 180 bp fragment was at two-thirds of its maximum intensity immediately after 24 h of light exposure and reached the maximum 12 h later. Dimethylthiourea partially inhibited ladder formation in rats reared in dim cyclic light and delayed the time of appearance of the 180 bp maximum by 6 h. By contrast, in rats reared in darkness the 180 bp fragment was undetected immediately after 3 h of light exposure and reached its maximum 2 days later. Pretreatment with DMTU completely eliminated DNA ladders in these rats. Alkaline gel electrophoresis revealed a pattern of single-strand DNA breaks, with relatively high molecular weight fragments, 6 h after light exposure of dark-reared rats. Single-strand DNA breaks in cyclic light rats corresponded with the onset of apoptotic ladders, but peak values preceded by 12 h the peak of DNA ladder formation. The quantity of 8-OHdG in retinal DNA remained close to control values in all samples with the exception of a peak of twice the control value 18 h after light exposure in the dark-reared rats and a value 60% higher 16 days after exposure in cyclic light animals. Dimethylthiourea had no effect on the amount of oxidized purine in any of the samples. The differences between dark-reared rats and rats reared in dim cyclic light in the kinetics of DNA fragmentation and in their response to treatment with DMTU is consistent with previous observations of fundamental differences in retinal cell physiology in these animals. In dim light-reared rats, the pathway to apoptosis may be qualitatively different from the pathway to net photoreceptor loss in rats reared in darkness. The lack of effect of DMTU on 8-OHdG formation suggests that the oxidation of DNA bases is not a causal factor in light-mediated photoreceptor cell death.     

一个新型钌(Ⅱ)配合物的合成、表征与DNA的键合及溶剂变色性质

合成和表征了1个新的钌(Ⅱ)配合物[Ru(bpy)₂(dpapz)](ClO₄)₂,其中bpy=2,2'-联吡啶,dpapz=联吡啶并[3,2-a:2,'3-'c]-6-氮杂-吩嗪.通过紫外可见光谱、荧光光谱、与溴化乙锭的竞争键合实验和粘度测量研究了该配合物与小牛胸腺DNA的键合性质,并研究了该配合物的紫外可见光谱和荧光光谱的溶剂变色性质.结果表明,该配合物是具有键合常数Kb=6.9×10⁵L/mol(50mmol/LNaCl)的DNA嵌入键合试剂和优良的荧光溶剂传感分子.     

Synthesis,Structure, Magnetic and Electrochemical Properties of a Dinuclear Copper Complex

A material for both magnetic coupling and electrocatalytic hydrogen evolution based on the copper complex, [(L)₂Cu₂] is formed by the reaction of CuCl₂ · 2H₂O with the tetradentate ligand 6‐(3‐aminomethylpropanol)‐2‐tert‐buty‐4‐methylphenol (H₂L), which is prepared by reaction of 2‐tert‐butyl‐4‐methylphenol, 3‐amino‐1‐propanol, and formaldehyde. Structural studies show that in the solid state complex 1 exhibits strong antiferromagnetic exchange interaction between copper(II) ions mediated by oxygen‐bridges. In liquid, 1 becomes a monomer, and can electrocatalyze hydrogen generation both from acetic acid with a turnover frequency (TOF) of 101.70 mol of hydrogen per mole of catalyst per hour at an overpotential (OP) of 941.6 mV (in DMF), and a natural buffer with a TOF of 650 mol of hydrogen per mole of catalyst per hour at an OP of 836.7 mV.