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China Medical Abstracts(Internal Medicine) 1994年第1期11卷 34-39页

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Promotion of Cleaner Technology in China's Chemical Industry(Ⅱ)

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China Chemical Reporter 2010年第11期21卷 12-12页

(Continued page 13,issue 10)Dyestuff sectorBy 2012,the dyestuff sector should apply thehydrogenation reduction cleaner productiontechnology of dyestuff and pigment intermediatesinto 60% of its capacity,complete thetechnological renovation of 250 000 t/a dyestuffand pigment intermediate capacity withcleaner production technologies like the hydrogenationreduction technology and the sulfurtrioxide sulfonation technology to

关键词： sector pigment apply aniline wastewater trioxide e

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Replacement of bacteriopheophytin in reaction centers from Rhodobacter sphaeroides RS601 with plant pheophytin

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Science China(Life Sciences) 2000年第1期43卷 21-29页

作者：曾小华吴永强沈允钢徐春和 Shanghai Institute of Plant Physiology Chinese Academy of Sciences Shanghai 200032 China

In the presence of acetone and an excess of exogenous plant pheophytins, bacterio-pheophytins in the reaction centers from Rhodobacter sphaeroides RS601 were replaced by pheophytins at sites HA and HB, when incubated at 43.5℃ for more than 15 min. The substitution of bacteriopheophytins in the reaction centers was 50% and 71% with incubation of 15 and 60 min, respectively. In the absorption spectra of pheophytin-replaced reaction centers (Phe RCs), bands assigned to the transition moments Qx (537 nm) and QY (758 nm) of bacteriopheophytin disappeared, and three distinct bands assigned to the transition moments Qx (509/542 nm) and QY (674 nm) of pheophytin appeared instead. Compared to that of the control reaction centers, the photochemical activities of Phe RCs are 78% and 71% of control, with the incubation time of 15 and 60 min. Differences might exist between the redox properties of Phe RC and of native reaction centers, but the substitution is significant, and the new system is available for

关键词： bacterial-photosynthetic reaction center pheophytin pigment replacement activity of light-induced electron transfer.

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Neurodegeneration:An early event of diabetic retinopathy

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World Journal of Diabetes 2010年第2期1卷 57-64页

作者： Marta Villarroel Andreea Ciudin Cristina Hernández Rafael Simó Diabetes and Metabolism Research Unit.Institut de Recerca Hospital Universitari Vall D'Hebron Universitat Autònoma de Barcelona CIBER for Diabetes and Associated Metabolic Diseases(CIBERDEM Instituto de Salut CarlosⅢ)

Diabetic retinopathy(DR) has been classically considered to be a microcirculatory disease of the retina caused by the deleterious metabolic effects of hyperglycemia per se and the metabolic pathways triggered by ***,retinal neurodegeneration is already present before any microcirculatory abnormalities can be detected in ophthalmoscopic *** other words,retinal neurodegeneration is an early event in the pathogenesis of DR which predates and participates in the microcirculatory abnormalities that occur in ***,the study of the mechanisms that lead to neurodegeneration will be essential to identify new therapeutic targets in the early stages of *** levels of glutamate and the overexpression of the renin-angiotensin-system play an essential role in the neurodegenerative process that occurs in diabetic *** neuroprotective factors,pigment epithelial derived factor,somatostatin and erythropoietin seem to be the most relevant and these will be considered in this ***,it should be noted that the balance between neurotoxic and neuroprotective factors rather than levels of neurotoxic factors alone will determine the presence or absence of retinal neurodegeneration in the diabetic *** strategies,based on either the delivery of neuroprotective agents or the blockade of neurotoxic factors,are currently being tested in experimental models and in clinical pilot *** these novel therapies will eventually supplement or prevent the need for laser photocoagulation or vitrectomy awaits the results of additional clinical research.

关键词： Diabetic retinopathy AngiotensinⅡ Erythropoietin Glutamate Retinal neurodegeneration Neuropeptides pigment epithelial derived factor Somatostatin

THE STUDY OF UV-PHOTOCHROMIC ANTI-COUNTERFEIT PAPER

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天津科技大学学报 2004年第S1期 199-204页

作者： Xiaoxiu Hao, Shuhui Yang, Qunce Feng, Yuru ZhouTianjin University of Science & Technology, Tianjin, China

The hydrophilicity, dispersity and minuteness of UV (ultraviolet)-photochromic special function materials and its retention and formation mechanisms in stock were comprehensively studied, and the retention mechanism of UV-photochromic fiber was also studied. In addition, according to the disadvantages of special function materials such as big grain, bad hydrophilicity, expensive price and so on, this paper displays our effects focused on the developing of anti-counterfeit pigments slurry system. Moreover, the properties and anti-counterfeit mechanism of the paper with different special function materials were researched by fluorescent spectrum.

关键词： UV(ultraviolet) photochromism anti-counterfeit paper pigment functional material fluorescent spectrum.

Extensive Quantitative Analysis of Gallstones

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International Journal of Clinical Medicine 2014年第1期5卷 42-50页

作者： Saadeldin A. Idris Kamal Elzaki Elsiddig Aamir A. Hamza Mohamed M. Hafiz Mohammed H. F. Shalayel Department of Biochemistry National College for Medical and Technical Studies Khartoum Sudan Department of Surgery College of Medicine University of Bahri Khartoum Sudan Department of Surgery Faculty of Medicine Alzaeim Alazhari University Khartoum Sudan Department of Surgery Faculty of Medicine University of Khartoum Khartoum Sudan

Background: The chemical composition of gallstones is essential to study aetiopathogenesis of gallstone disease. Objective: To determine the composition of gallstones in a Sudanese population. Patients and methods: It describes an extensive quantitative analysis of gallstones from patients presented with symptomatic gall stone disease and treated by cholecystectomy after the acceptance of the pre-given informed consent in Khartoum teaching hospital in the period between Jan 2010 and Dec 2010. Using a pretested questionnaire data collected from and analyzed statistically by SPSS computer program version 21. Results: Data are analyzed from 94 patients (six males and 88 females). Cholesterol stones showed a significantly higher cholesterol content than pigment stones (p = 0.0042), though not significantly higher than mixed stones. Their phospholipids content and inorganic phosphates were higher than in the other types of stones and oxalate content was significantly elevated in comparison with mixed stones (p = 0.0402). In mixed stones, the cholesterol, bile acids, and bilirubin were intermediate between cholesterol and pigment stones, whereas triglycerides were significantly more than pigment stones (p = 0.0007). Bilirubin (p = 0.0021) and bile acids (p = 0.0016) were significantly higher than cholesterol stones (p = 0.0001) and (p = 0.0001) respectively. However, they contained the lowest amounts of sodium, potassium, magnesium, and oxalate. In pigment stones, bilirubin was significantly higher (p = 0.0001) than both groups. Conclusion: Collaborations between surgeons, nutritionists, biochemists, and physicians should be stimulated in future studies to define the different types of gall stones in different areas in Sudan and the relevancy of such types with diets’ traditions.

关键词： Cholesterol Stone (CS) Gallstone (GS) Mixed Stone (MS) pigment Stone (PS)

Mathematical Modeling of Exudative Retinal Detachment

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Applied Mathematics 2017年第1期8卷 44-56页

作者： Ram Avtar Swati Srivastava Department of Mathematics Harcourt Butler Technical University Kanpur India

A simple mathematical model for the exudative retinal detachment has been developed. The model takes into consideration a typical retinal blister with unknown shape and the fluid flow caused by its accumulation in the subretinal space through the fluid-leakage into the subretinal space from the choriocapillar is across the outer blood-retina barrier described by Darcy’s law. The theory of bending beams is applied to model the deformation of the retinal blister. The boundary value problem describing the retinal deformation in dimensionless form is solved using the perturbation method. The computational results for the retinal deformation are presented through graphs to illustrate the sensitivity of the deformation to the elastic modulus, the moment of inertia and intraocular pressure and discussed.

关键词： Retinal pigment Epithelium Subretinal Space Choriocapillaris Vitreous Humor

The LysR Transcription Factor, HexS, Is Required for Glucose Inhibition of Prodigiosin Production by <i>Serratia marcescens</i>

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Advances in Microbiology 2012年第4期2卷 511-517页

作者： Nicholas A. Stella James E. Fender Roni M. Lahr Eric J. Kalivoda Robert M. Q. Shanks Charles T. Campbell Laboratory of Ophthalmic Microbiology Department of Ophthalmology University of Pittsburgh Pittsburgh USA College of Medicine University of Vermont Burlington USA

Generation of many useful microbe-derived secondary metabolites, including the red pigment prodigiosin of the bacterium Serratia marcescens, is inhibited by glucose. In a previous report, a genetic approach was used to determine that glucose dehydrogenase activity (GDH) is required for inhibiting prodigiosin production and transcription of the prodigiosin biosynthetic operon (pigA-N). However, the transcription factor(s) that regulate this process were not characterized. Here we tested the hypothesis that HexS, a LysR-family transcription factor similar to LrhA of Escherichia coli, is required for inhibition of prodigiosin by growth in glucose. We observed that mutation of the hexS gene in S. marcescens allowed the precocious production of prodigiosin in glucose-rich medium conditions that completely inhibited prodigiosin production by the wild type. Unlike previously described mutants able to generate prodigiosin in glucoserich medium, hexS mutants exhibited GDH activity and medium acidification similar to the wild type. Glucose inhibittion of pigA expression was shown to be dependent upon HexS, suggesting that HexS is a key transcription factor in secondary metabolite regulation in response to medium pH. These data give insight into the prodigiosin regulatory pathway and could be used to enhance the production of secondary metabolites.

关键词： pigment Antibiotic Transcription Factor Secondary Metabolite

The Effects of Salicylic Acid on Helianthus annuus L. Exposed to Quizalofop-P-Ethyl

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American Journal of Plant Sciences 2015年第14期6卷 2412-2425页

作者： Dilek Dilek Bayram Emel Yigit Gulcin Beker Akbulut Department of Biology Science and Art Faculty Inonu University Malatya Turkey Department of Organic Agriculture Tunceli Vocational School Tunceli University Tunceli Turkey

Herbicides adversely affect both the target plant and its environment. In this study, Helianthus annuus L. cv. “Oliva CL” was treated post-emergence with 0.3 to 3.1 mM quizalofop-p-ethyl. The peroxidase activity (POD), ascorbate peroxidase activity (APX), lipid peroxidation, pigment sys tem and total phenolic content were then determined on the 1st, 5th, 10th and 15th days following treatment. The POD activity increased on all application days, and the APX activity increased on the 5th day and decreased on the 10th and 15th days. In addition, the malondialdehyde (MDA) content was increased on the 1st, 5th, 10th and 15th days, except for the in H. annuus plants treated with 1.6 to 3.1 mM quizalofop-p-ethyl. The total chlorophyll, carotenoid and total phenolic content were important and changed in a time dependent manner. In the present study, we also investigated the possible role of salicylic acid (SA) in protecting H. annuus seedlings from herbicide toxicity. The plants were first treated with 0.5 mM SA pre-emergence and then treated with 0.3 to 3.1 mM quizalofop-p-ethyl herbicide post-emergence. In general, increases in the POD activity and MDA content were observed in the treatment groups on all application days. In the treated groups, the APX activity increased until the 15th day. In the SA pre-treated plants, the total phenollic, total chlorophyll and carotenoid content were also important in a time dependent manner.

关键词： Ascorbate Peroxidase Lipid Peroxidation Peroxidase pigment Quizalofop-P-Ethyl Salicylic Acid Total Phenolic

Lipofuscins prepared by modification of photoreceptor cells via glycation or lipid peroxidation show the similar phototoxicity

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World Journal of Experimental Medicine 2016年第4期6卷 63-71页

作者： Alexander Dontsov Anna Koromyslova Mikhail Ostrovsky Natalia Sakina Emanuel Institute of Biochemical Physics Russian Academy of Sciences

AIM To investigate the effect of two ways of lipofuscin production(lipid peroxidation and glycation) on lipofuscin fluorescence characteristics and phototoxicity and to compare them with the properties of natural *** Model lipofuscins were prepared on the basis of bovine photoreceptor outer segments(POS) with bisretinoid A2 E addition. One set of samples was prepared from POS modified by lipid peroxidation,while another set from POS modified by glycation with fructose. Fluorescent properties and kinetics of photoinduced superoxide generation of model lipofuscins and human retinal pigment epithelium(RPE) lipofuscin were compared. The fluorescence spectra of samples were measured at 365 nm excitation wavelength and 380-650 emission wavelength. RESULTS The fluorescence spectra of model lipofuscins are almost the same as the spectrum of natural lipofuscin. Visible light irradiation of both model lipofuscins and natural lipofuscin isolated from RPE cells leads to decrease of a fluorescence maximum at 550 nm and to appearance of a distinct,new maximum at 445-460 nm. The rate of photogeneration of reactive oxygen forms by both model lipofuscins was almost the same and approximately two times less than that of RPE lipofuscin *** These data suggest that fluorescent characteristics and phototoxicity of lipofuscin granules depend only to an insignificant degree on the oxidative modification of POS proteins and lipids,and generally are defined by the bisretinoid fluorophores contained in them.

关键词： Model lipofuscins Retinal pigment epithelium Photoreceptor outer segments Bisretinoids Glycation Lipid peroxidation Superoxide