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1.
Status of reduced glutathione in primary cultures of rat hepatocytes and the effect on conjugation of benzo[a]pyrene-7,8-dihydrodiol-9,10-oxide 总被引:1,自引:0,他引:1
Helen Morrison Viveca Hammarskiöld Bengt Jernström 《Chemico-biological interactions》1983,45(2):235-242
The intracellular level of reduced glutathione (GSH) and GSH conjugation have been investigated in primary cell cultures of hepatocytes isolated from control rats, phenobarbitone (PB) and 3-methylcholanthrene (MC) treated rats. The data demonstrate that in all cell cultures the GSH concentrations show a triphasic pattern: (i) within 1 h of culture an initial marked decrease to 50% of the levels found in fresh hepatocytes; (ii) recovery of GSH concentrations to above the levels observed in fresh cells. This occurs after 6 h in culture with control cells and after 10-24 h with cells from either PB or MC treated rats and was most prominent in cells from PB-treated rats. (iii) A slow decline to between 30 and 40 nmol GSH/mg protein from 24 to 96 h in culture. Synthesis of GSH was slower in cultured cells from PB treated rats and this was confirmed by the resynthesis rates when diethylmaleate (DEM) was used to deplete GSH. The formation of GSH conjugates with racemic 7 beta,8 alpha-dihydroxy-9 alpha,10 alpha-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (BPDE) was measured in control cells in suspension and after 3 and 24 h in culture. Despite the decrease in GSH concentrations observed between 1 and 4 h after culture, the conjugation rates were not decreased. 相似文献
2.
Charlotte ?ngstr?m-Br?nnstr?m Gunn Engvall Tara Mullaney Kristina Nilsson Gun Wickart-Johansson Anna-Maja Sv?rd Tufve Nyholm Jack Lindh Viveca Lindh 《PloS one》2015,10(10)
Approximately 300 children, from 0 to 18 years old, are diagnosed with cancer in Sweden every year. Of these children, 80–90 of them undergo radiotherapy treatment for their cancer. Although radiotherapy is an encounter with advanced technology, few studies have investigated the child’s and the parent’s view of the procedure. As part of an ongoing multicenter study aimed to improve patient preparation and the care environment in pediatric radiotherapy, this article reports the findings from interviews with parents at baseline. The aim of the present study was twofold: to describe parents’ experience when their child undergoes radiotherapy treatment, and to report parents’ suggestions for improvements during radiotherapy for their children. Sixteen mothers and sixteen fathers of children between 2–16 years old with various cancer diagnoses were interviewed. Data were analyzed using content analysis. The findings showed that cancer and treatment turns people’s lives upside down, affecting the entire family. Further, the parents experience the child’s suffering and must cope with intense feelings. Radiotherapy treatment includes preparation by skilled and empathetic staff. The parents gradually find that they can deal with the process; and lastly, parents have suggestions for improvements during the radiotherapy treatment. An overarching theme emerged: that despair gradually turns to a sense of security, with a sustained focus on and close interaction with the child. In conclusion, an extreme burden was experienced around the start of radiotherapy, though parents gradually coped with the process. 相似文献
3.
LV Faro JM de Almeida CC Cirne-Santos VA Giongo LR Castello-Branco Ide B Oliveira JE Barbosa AC Cunha VF Ferreira MC de Souza IC Paixão MC de Souza 《Bioorganic & medicinal chemistry letters》2012,22(15):5055-5058
The emergence of a multidrug-resistant HIV-1 strain and the toxicity of anti-HIV-1 compounds approved for clinical use are the most significant problems facing antiretroviral therapies. Therefore, it is crucial to find new agents to overcome these issues. In this study, we synthesized a series of new oxoquinoline acyclonucleoside phosphonate analogues (ethyl 1-[(diisopropoxyphosphoryl)methyl]-4-oxo-1,4-dihydroquinoline-3-carboxylates 3a-3k), which contained different substituents at the C6 or C7 positions of the oxoquinoline nucleus and an N1-bonded phosphonate group. We subsequently investigated these compounds' in vitro inhibitory effects against HIV-1-infected peripheral blood mononuclear cells (PBMCs). The most active compounds were the fluoro-substituted derivatives 3f and 3g, which presented excellent EC(50) values of 0.4±0.2 μM (3f) and 0.2±0.005 μM (3g) and selectivity index values (SI) of 6240 and 14675, respectively. 相似文献
4.
Pollen productivity estimates of key European plant taxa for quantitative reconstruction of past vegetation: a review 总被引:2,自引:2,他引:0
Anna Broström Anne Birgitte Nielsen Marie-José Gaillard Kari Hjelle Florence Mazier Heather Binney Jane Bunting Ralph Fyfe Viveca Meltsov Anneli Poska Satu Räsänen Welmoed Soepboer Henrik von Stedingk Henna Suutari Shinya Sugita 《Vegetation History and Archaeobotany》2008,17(5):461-478
Information on the spatial distribution of past vegetation on local, regional and global scales is increasingly used within
climate modelling, nature conservancy and archaeology. It is possible to obtain such information from fossil pollen records
in lakes and bogs using the landscape reconstruction algorithm (LRA) and its two models, REVEALS and LOVE. These models assume
that reliable pollen productivity estimates (PPEs) are available for the plant taxa involved in the quantitative reconstructions
of past vegetation, and that PPEs are constant through time. This paper presents and discusses the PPEs for 15 tree and 18
herb taxa obtained in nine study areas of Europe. Observed differences in PPEs between regions may be explained by methodological
issues and environmental variables, of which climate and related factors such as reproduction strategies and growth forms
appear to be the most important. An evaluation of the PPEs at hand so far suggests that they can be used in modelling applications
and quantitative reconstructions of past vegetation, provided that consideration of past environmental variability within
the region is used to inform selection of PPEs, and bearing in mind that PPEs might have changed through time as a response
to climate change. Application of a range of possible PPEs will allow a better evaluation of the results. 相似文献
5.
Abreu PA da Silva VA Santos FC Castro HC Riscado CS de Souza MT Ribeiro CP Barbosa JE dos Santos CC Rodrigues CR Lione V Correa BA Cunha AC Ferreira VF de Souza MC Paixão IC 《Current microbiology》2011,62(5):1349-1354
Herpes simplex virus is an important human pathogen responsible for a range of diseases from mild uncomplicated mucocutaneous infections to life-threatening ones. Currently, the emergence of Herpes simplex virus resistant strains increased the need for more effective and less cytotoxic drugs for Herpes treatment. In this work, we synthesized a series of oxoquinoline derivatives and experimentally evaluated the antiviral activity against acyclovir resistant HSV-1 strain as well as their cytotoxity profile. The most active compound (3b), named here as Fluoroxaq-3b, showed a promising profile with a better cytotoxicity profile than acyclovir. The theoretical analysis of the structure-activity relationship of these compounds revealed some stereoelectronic properties such as lower LUMO energy and lipophilicity, besides a higher polar surface area and number of hydrogen bond acceptor groups as important parameters for the antiviral activity. Fluoroxaq-3b showed a good oral theoretical bioavailability, according to Lipinski rule of five, with a promising profile for further in vivo analysis. 相似文献
6.
Anders Pettersson Lotta Uggla Viveca Backman 《Journal of chromatography. B, Analytical technologies in the biomedical and life sciences》1997,692(2):839
Using high-performance liquid chromatography (HPLC) with multigradient elution, (asymmetric-DMA, ADMA) and (symmetric-DMA, SDMA) can be separated from human plasma samples. The dimethylarginine compounds in plasma, after extraction with a cation-exchange column, are converted to fluorescent derivatives with o-phthaldialdehyde (OPA) in an alkaline medium and the derivatives are separated simultaneously within 50 min on a reversed-phase column (Ultracarb 3 ODS(20)). The recoveries of ADMA and SDMA are over 80% and the method permits quantitative determination of dimethylated arginines at concentrations as low as 0.1 μmol/l in human plasma. 相似文献
7.
Gunn Engvall Charlotte ?ngstr?m-Br?nnstr?m Tara Mullaney Kristina Nilsson Gun Wickart-Johansson Anna-Maja Sv?rd Tufve Nyholm Jack Lindh Viveca Lindh 《PloS one》2016,11(4)
Approximately 300 children ages 0 to 18 are diagnosed with cancer in Sweden every year, and 80 to 90 of them undergo radiotherapy treatment. The aim was to describe children’s experiences of preparing for and undergoing radiotherapy, and furthermore to describe children’s suggestions for improvement. Thirteen children between the ages of 5 and 15 with various cancer diagnoses were interviewed. Data was analyzed using qualitative content analysis. The findings revealed five categories: positive and negative experiences with hospital stays and practical arrangements; age-appropriate information, communication, and guidance to various degrees; struggle with emotions; use of distraction and other suitable coping strategies; and children’s suggestions for improvement during radiotherapy. An overarching theme emerged: “It is tough and tiring but it works”. Some key areas were: explanatory visits, the need for information and communication, being afraid, discomfort and suffering, the need for media distraction, dealing with emotions, and the need for support. A systematic, family-centered preparation program could possible help families prepare and individualized distraction during radiotherapy could contribute to reducing distress. Further studies with interventions could clarify successful programs. 相似文献
8.
Anders Johansson Anna Aspan Elisabeth Bagge Viveca Båverud Björn E Engström Karl-Erik Johansson 《BMC microbiology》2006,6(1):47-12
Background
Clostridium perfringens, a serious pathogen, causes enteric diseases in domestic animals and food poisoning in humans. The epidemiological relationship between C. perfringens isolates from the same source has previously been investigated chiefly by pulsed-field gel electrophoresis (PFGE). In this study the genetic diversity of C. perfringens isolated from various animals, from food poisoning outbreaks and from sludge was investigated. 相似文献9.
Ola Fjellstr?m Sibel Akkaya Hans-Georg Beisel Per-Olof Eriksson Karl Erixon David Gustafsson Ulrik Jurva Daiwu Kang David Karis Wolfgang Knecht Viveca Nerme Ingemar Nilsson Thomas Olsson Alma Redzic Robert Roth Jenny Sandmark Anna Tigerstr?m Linda ?ster 《PloS one》2015,10(1)
Activated factor XI (FXIa) inhibitors are anticipated to combine anticoagulant and profibrinolytic effects with a low bleeding risk. This motivated a structure aided fragment based lead generation campaign to create novel FXIa inhibitor leads. A virtual screen, based on docking experiments, was performed to generate a FXIa targeted fragment library for an NMR screen that resulted in the identification of fragments binding in the FXIa S1 binding pocket. The neutral 6-chloro-3,4-dihydro-1H-quinolin-2-one and the weakly basic quinolin-2-amine structures are novel FXIa P1 fragments. The expansion of these fragments towards the FXIa prime side binding sites was aided by solving the X-ray structures of reported FXIa inhibitors that we found to bind in the S1-S1’-S2’ FXIa binding pockets. Combining the X-ray structure information from the identified S1 binding 6-chloro-3,4-dihydro-1H-quinolin-2-one fragment and the S1-S1’-S2’ binding reference compounds enabled structure guided linking and expansion work to achieve one of the most potent and selective FXIa inhibitors reported to date, compound 13, with a FXIa IC50 of 1.0 nM. The hydrophilicity and large polar surface area of the potent S1-S1’-S2’ binding FXIa inhibitors compromised permeability. Initial work to expand the 6-chloro-3,4-dihydro-1H-quinolin-2-one fragment towards the prime side to yield molecules with less hydrophilicity shows promise to afford potent, selective and orally bioavailable compounds. 相似文献
10.
Fernanda da C. Santos Paula Abreu Helena C. Castro Izabel C.P.P. Paixão Claudio C. Cirne-Santos Viveca Giongo Juliana E. Barbosa Bruno R. Simonetti Valéria Garrido Dumith Chequer Bou-Habib David de O. Silva Pedro N. Batalha Jairo R. Temerozo Thiago M. Souza Christiane M. Nogueira Anna C. Cunha Carlos R. Rodrigues Vitor F. Ferreira Maria C.B.V. de Souza 《Bioorganic & medicinal chemistry》2009,17(15):5476-5481
In the present article, we describe the synthesis, anti-HIV1 profile and molecular modeling evaluation of 11 oxoquinoline derivatives. The structure–activity relationship analysis revealed some stereoelectronic properties such as LUMO energy, dipole moment, number of rotatable bonds, and of hydrogen bond donors and acceptors correlated with the potency of compounds. We also describe the importance of substituents R2 and R3 for their biological activity. Compound 2j was identified as a lead compound for future investigation due to its : (i) high activity against HIV-1, (ii) low cytotoxicity in PBMC, (iii) low toxic risks based on in silico evaluation, (iv) a good theoretical oral bioavailability according to Lipinski ‘rule of five’, (v) higher druglikeness and drug-score values than current antivirals AZT and efavirenz. 相似文献