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111.
Antony PB Black Hansha Bhayani Clive AJ Ryder Janet MM Gardner-Medwin Taunton R Southwood 《Arthritis research & therapy》2001,4(3):177
A study was done to determine if the differentiation and activation phenotype of T cells in synovial fluid (SF) from patients with juvenile idiopathic arthritis (JIA) is associated with T-cell proliferation in situ. Mononuclear cells were isolated from 44 paired samples of peripheral blood and SF. Differentiation and activation markers were determined on CD4 and CD8 T cells by flow cytometry. Cell-cycle analysis was performed by propidium iodide staining, and surface-marker expression was also assessed after culture of the T cells under conditions similar to those found in the synovial compartment. The majority of the T cells in the SF were CD45RO+CD45RBdull. There was greater expression of the activation markers CD69, HLA-DR, CD25 and CD71 on T cells from SF than on those from peripheral blood. Actively dividing cells accounted for less than 1% of the total T-cell population in SF. The presence or absence of IL-16 in T-cell cultures with SF or in a hypoxic environment did not affect the expression of markers of T-cell activation. T cells from the SF of patients with JIA were highly differentiated and expressed early and late markers of activation with little evidence of in situ proliferation. This observation refines and extends previous reports of the SF T-cell phenotype in JIA and may have important implications for our understanding of chronic inflammation. 相似文献
112.
The anti-algal activity of five macrophyte extracts on the cyanobacterium Microcystis aeruginosa in Egypt was investigated in 2013. Extract activity varied according to plant type, extracting solvent and its concentration. The highest inhibitory activity was achieved with ethanol extract at a concentration of 80 mg l?1, followed by chloroformic extracts, at 60 mg l?1. Methanolic extracts of Eichhornia crassipes and Polygonum tomentosum inhibited growth of Microcystis aeruginosa at all concentrations. Acetonic extracts inhibited algal growth at 60 mg l?1, except for the extract of Ceratophyllum subdemersum, which showed stimulation of M. aeruginosa growth. Eichhornia crassipes ethanolic extract exerted the most powerful inhibition by more than five-fold, 570.17%, followed by those of P. tomentosum, Saccharum spontaneum, Ceratophyllum demersum and C. subdemersum, 559.48, 553.99, 544.11 and 366.51%, respectively. Phytochemical screening for the tested plant extracts revealed the presence of biologically active substances of different concentrations, with P. tomentosum having the highest polyphenols, 1.95% of dry weight. 相似文献
113.
Lacey M Bohday J Fonseka SM Ullah AI Whitehead SA 《The Journal of steroid biochemistry and molecular biology》2005,96(3-4):279-286
There is evidence that certain phytoestrogens can inhibit key steroidogenic enzymes although most studies have been carried out on microsomal or purified enzyme preparations, some using cell lines. This study was designed to test the hypothesis that low doses of phytoestrogens, at concentrations that would be attained through the diet, could inhibit 3beta-hydroxysteroid dehydrogenase (HSD) and/or aromatase in primary cultures of human granulosa-luteal (GL) cells and that this effect was due to a decrease in the expression of these proteins. Based on published evidence, eight compounds were selected for investigation and these included the flavones apigenin and quercetin, the isoflavones genistein, biochanin A and daidzein, the lignans, enterodiol and enterolactone, and the mycotoxin zearalenone. Human GL cells were cultured for 48 h in the presence of these phytoestrogens at concentrations ranging from 0.01 to 100 microM and after addition of fresh media the conversion of pregnenolone to progesterone or androstenedione to oestradiol over a 4h period was measured. Biochanin A was the only phytoestrogen that displayed any dose-dependent inhibition of 3beta-HSD, others showing inhibition at doses >/=10 microM. Apigenin and quercetin only inhibited aromatase/17beta-HSD at high doses as did genistein, biochanin A and daidzein. The lignans had weak inhibitory effects on aromatase/17beta-HSD, whilst zearalenone showed potent inhibition at 0.1 microM. Phytoestrogens did not exert any significant effects on protein expression of 3beta-HSD or aromatase as determined by Western blots. It is concluded that steroidogenic enzymes are inhibited by phytoestrogens in primary cultures of human GL cells but these cells are less sensitive to the effects of phytoestrogens than cell-free systems. This may be due to poor lipid solubility or cellular metabolism. We have also shown for the first time that phytoestrogens do not act by inhibiting the cellular concentration of 3beta-HSD and aromatase even though exposure time would have allowed for changes in gene expression. 相似文献
114.
Equine arteritis virus (EAV) induces apoptosis in infected cells. Cell death caused by EAV has been studied mainly using three cell lines, BHK-21, RK-13 and Vero cells. The mechanism of apoptosis varies among cell lines and results cannot be correlated owing to differences in EAV strains used. We evaluated different markers for apoptosis in BHK-21, RK-13 and Vero cell lines using the Bucyrus EAV reference strain. Acridine orange/ethidium bromide staining revealed morphological changes in infected cells, while flow cytometry indicated the extent of apoptosis. We also observed DNA fragmentation, but the DNA ladder was detected at different times post-infection depending on the cell line, i.e., 48, 72 and 96 h post-infection in RK-13, Vero and BHK-21 cells, respectively. Measurement of viral titers obtained with each cell line indicated that apoptosis causes interference with viral replication and therefore decreased viral titers. As an unequivocal marker of apoptosis, we measured the expression of caspase-3 and caspases-8 and -9 as extrinsic and intrinsic markers of apoptosis pathways, respectively. Caspase-8 in BHK-21 cells was the only protease that was not detected at any of the times assayed. We found that Bucyrus EAV strain exhibited a distinctive apoptosis pathway depending on the cell line. 相似文献
115.
Nicolli Bellotti de Souza Isabel M de Andrade Paula F Carneiro Guilherme AM Jardim Isadora MM de Melo Eufranio N da Silva Júnior Antoniana Ursine Krettli 《Memórias do Instituto Oswaldo Cruz》2014,109(5):546-552
Due to the recent advances of atovaquone, a naphthoquinone, through clinical trials
as treatment for malarial infection, 19 quinone derivatives with previously reported
structures were also evaluated for blood schizonticide activity against the malaria
parasite Plasmodium falciparum. These compounds include 2-hydroxy-3-methylamino
naphthoquinones (2-9), lapachol (10), nor-lapachol (11), iso-lapachol (12), phthiocol
(13) and phenazines (12-20). Their cytotoxicities were also evaluated against human
hepatoma and normal monkey kidney cell lines. Compounds 2 and 5 showed the highest
activity against P. falciparum chloroquine-resistant blood-stage parasites (clone
W2), indicated by their low inhibitory concentration for 50% (IC50) of
parasite growth. The therapeutic potential of the active compounds was evaluated
according to the selectivity index, which is a ratio of the cytotoxicity minimum
lethal dose which eliminates 50% of cells and the in vitro IC50.
Naphthoquinones 2 and 5, with activities similar to the reference antimalarial
chloroquine, were also active against malaria in mice and suppressed parasitaemia by
more than 60% in contrast to compound 11 which was inactive. Based on their in vitro
and in vivo activities, compounds 2 and 5 are considered promising molecules for
antimalarial treatment and warrant further study. 相似文献
116.
Jennifer H Humphreys Jessica AB van Nies Jackie Chipping Tarnya Marshall Annette HM van der Helm-van Mil Deborah PM Symmons Suzanne MM Verstappen 《Arthritis research & therapy》2014,16(6)
Introduction
This study aimed to investigate rheumatoid factor (RF) and anti-citrullinated protein antibody (ACPA) status and levels as predictors of mortality in two large cohorts of patients with early inflammatory arthritis (EIA).Methods
Data from the Norfolk Arthritis Register (NOAR) and Leiden Early Arthritis Clinic (EAC) cohorts were used. At baseline, patients had demographic data and smoking status recorded; RF, ACPA and inflammatory markers were measured in the local laboratories. Patients were flagged with national death registers until death or censor date. Antibody status was stratified as negative, low or high positive by RF and ACPA levels individually. In addition, patients were grouped as seronegative, RF positive, ACPA positive or double antibody (RF and ACPA) positive. Cox regression models explored associations between antibody status and mortality adjusting for age, sex, smoking status, inflammatory markers and year of enrolment.Results
A total of 4962 patients were included, 64% were female. Median age at onset was 56 (NOAR) and 54 (EAC) years. In NOAR and EAC respectively, 35% and 42% of patients were ACPA/RF positive. When antibody status was stratified as negative, low or high positive, there were no consistent findings between the two cohorts. Double antibody positivity was associated with excess mortality in both cohorts compared to seronegative patients: NOAR and EAC respective adjusted HR (95% confidence interval) 1.35 (1.09 to 1.68) and 1.58 (1.16 to 2.15).Conclusions
Patients with EIA who are seropositive for both RF and ACPA have increased mortality compared to those who are single positive or seronegative. Antibody level in seropositive patients was not consistently associated with excess mortality.Electronic supplementary material
The online version of this article (doi:10.1186/s13075-014-0483-3) contains supplementary material, which is available to authorized users. 相似文献117.
Camila Carlos Mathias M Pires Nancy C Stoppe Elayse M Hachich Maria IZ Sato Tânia AT Gomes Luiz A Amaral Laura MM Ottoboni 《BMC microbiology》2010,10(1):161
Background
Escherichia coli strains are commonly found in the gut microflora of warm-blooded animals. These strains can be assigned to one of the four main phylogenetic groups, A, B1, B2 and D, which can be divided into seven subgroups (A0, A1, B1, B22, B23, D1 and D2), according to the combination of the three genetic markers chuA, yjaA and DNA fragment TspE4.C2. Distinct studies have demonstrated that these phylo-groups differ in the presence of virulence factors, ecological niches and life-history. Therefore, the aim of this work was to analyze the distribution of these E. coli phylo-groups in 94 human strains, 13 chicken strains, 50 cow strains, 16 goat strains, 39 pig strains and 29 sheep strains and to verify the potential of this analysis to investigate the source of fecal contamination. 相似文献118.
The effect of measuring light photolysis on the kinetics of reaction of reduced cytochrome a3 and carbon monoxide. 下载免费PDF全文
The kinetics of reaction of reduced cytochrome a3 and CO are re-investigated by non-linear optimization techniques. When photolysis by the monitoring light is taken into account, the experimental data are best fitted by a single-intermediate mechanism. 相似文献
119.
This paper unfolds the events, the people and the times that led up to the
founding of AChemS and fashioned its character during its early formative
years. It describes the path over which AChemS came, going from the
original assertions and denials for the need of such an organization to its
later inception and nascent development. This narration highlights such
topics as the debate over the need for AChemS, the role of National Science
Foundation in the founding of AChemS, the derivation of the Association's
name, the choice of Sarasota and the Hyatt House as the meeting site, the
generation of the programs for the early annual meetings, the adoption of
the bylaws, the process of incorporation and tax deferment, and the birth
of the Givaudan Lectureship. Most emphatically highlighted, however, is the
enthusiasm, commitment and hard work that the members of the chemosensory
research community displayed in bringing AChemS to fruition.
相似文献
120.
Rahula O.B. Wijesekera Anura L. Jayewardene Botalegé D. Fonseka 《Phytochemistry》1973,12(11):2697-2704
Gas chromatography of citronella oil showed that the Ceylon variety (Lenabatu) contained large amounts of monoterpene hydrocarbons, while the Java variety (Mahapengiri) contained only small amounts, mainly limonene. Both types contained comparable amounts of geraniol, and the Java type more of citronellol and citronellal. In addition the Ceylon type contained tricyclene, methyl eugenol, methyl isoeugenol, eugenol and l-borneol. The GLC profiles enable the identification of the type of oil and the detection of kerosene as a possible adulterant. The variety that grows wild in Ceylon (Mana) was quite different to both cultivated types. 相似文献