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1.
TÜNDE TÓTH OTTÓ ZSIROS MIHÁLY KIS GYŐZŐ GARAB LÁSZLÓ KOVÁCS 《Plant, cell & environment》2012,35(12):2075-2086
Despite intense research, the mechanism of Cd2+ toxicity on photosynthesis is still elusive because of the multiplicity of the inhibitory effects and different barriers in plants. The quick Cd2+ uptake in Synechocystis PCC 6803 permits the direct interaction of cadmium with the photosynthetic machinery and allows the distinction between primary and secondary effects. We show that the CO2‐dependent electron transport is rapidly inhibited upon exposing the cells to 40 µm Cd2+ (50% inhibition in ~15 min). However, during this time we observe only symptoms of photosystem I acceptor side limitation and a build of an excitation pressure on the reaction centres, as indicated by light‐induced P700 redox transients, O2 polarography and changes in chlorophyll a fluorescence parameters. Inhibitory effects on photosystem II electron transport and the degradation of the reaction centre protein D1 can only be observed after several hours, and only in the light, as revealed by chlorophyll a fluorescence transients, thermoluminescence and immunoblotting. Despite the marked differences in the manifestations of these short‐ and long‐term effects, they exhibit virtually the same Cd2+ concentration dependence. These data strongly suggest a cascade mechanism of the toxic effect, with a primary effect in the dark reactions. 相似文献
2.
Introduction
Fibromyalgia is difficult to treat and requires the use of multiple approaches. This study is a randomized controlled trial of qigong compared with a wait-list control group in fibromyalgia.Methods
One hundred participants were randomly assigned to immediate or delayed practice groups, with the delayed group receiving training at the end of the control period. Qigong training (level 1 Chaoyi Fanhuan Qigong, CFQ), given over three half-days, was followed by weekly review/practice sessions for eight weeks; participants were also asked to practice at home for 45 to 60 minutes per day for this interval. Outcomes were pain, impact, sleep, physical function and mental function, and these were recorded at baseline, eight weeks, four months and six months. Immediate and delayed practice groups were analyzed individually compared to the control group, and as a combination group.Results
In both the immediate and delayed treatment groups, CFQ demonstrated significant improvements in pain, impact, sleep, physical function and mental function when compared to the wait-list/usual care control group at eight weeks, with benefits extending beyond this time. Analysis of combined data indicated significant changes for all measures at all times for six months, with only one exception. Post-hoc analysis based on self-reported practice times indicated greater benefit with the per protocol group compared to minimal practice.Conclusions
This study demonstrates that CFQ, a particular form of qigong, provides long-term benefits in several core domains in fibromyalgia. CFQ may be a useful adjuvant self-care treatment for fibromyalgia.Trial registration
clinicaltrials.gov NCT00938834. 相似文献3.
PETER BOGNER DENYS N. WHEATLEY CSABA BORBLY ATTILA MISETA 《Cell biology international》1996,20(11):741-749
Exchange of erythrocyte intracellular (i/c) K+for extracellular (e/c) Na+in human erythrocytes treated with sub-CMC concentrations of the non-ionic detergent Brij 58 can be stopped by reincubation in serum or albumin containing solutions. The progressive equilibration of the K+contents of detergent-treated human erythrocytes with the incubation medium was reversed by an albumin-mediated withdrawal of detergent molecules from the cell. Re-establishment of near normal [K+] in terms of K+/kg water proceeds in two ways: (i) a metabolism-dependent net accumulation of K+ions; and (ii) a metabolism-independent shrinkage of erythrocytes, this being the more significant factor. 相似文献
4.
Kong Bung Choo Yuen Loon Soon Phan Nguyen Nhi Nguyen Michele Sook Yuin Hiew Chiu-Jung Huang 《Journal of biomedical science》2014,21(1)
Background
Two mature miRNA species may be generated from the 5’ and 3’ arms of a pre-miRNA precursor. In most cases, only one species remains while the complementary species is degraded. However, co-existence of miRNA-5p and -3p species is increasingly being reported. In this work, we aimed to systematically investigate co-expression of miRNA-5p/3p in colon cancer cells in a genome-wide analysis, and to examine cross-targeting of the dysregulated miRNAs and 5p/3p species.Results
Four colon cancer cell lines were examined relative to two normal colon tissues. Of the 1,190 miRNAs analyzed, 92 and 36 were found to be up- or down-regulated, respectively, in cancer cells. Nineteen co-expressed miRNA-5p/3p pairs were further identified suggesting frequent 5p/3p co-accumulation in colon cancer cells. Of these, 14 pairs were co-up-regulated and 3 pairs were co-down-regulated indicating concerted 5p/3p dysregulation. Nine dysregulated miRNA pairs fell into three miRNA gene families, namely let-7, mir-8/200 and mir-17, which showed frequent cross-targeting in the metastasis process. Focusing on the let-7d-5p/3p pair, the respectively targeted IGF1R and KRAS were shown to be in a reverse relationship with expression of the respective miRNA, which was confirmed in transient transfection assays using let-7d mimic or inhibitor. Targeting of KRAS by let-7d was previous reported; targeting of IGF1R by let-7d-5p was confirmed in luciferase assays in this study. The findings of let-7d-5p/3p and multiple other miRNAs targeting IGF1R, KRAS and other metastasis-related factors suggest that 5p/3p miRNAs contribute to cross-targeting of multiple cancer-associated factors and processes possibly to evade functional abolishment when any one of the crucial factors are inactivated.Conclusions
miRNA-5p/3p species are frequently co-expressed and are coordinately regulated in colon cancer cells. In cancer cells, multiple cross-targeting by the miRNAs, including the co-existing 5p/3p species, frequently occurs in an apparent safe-proof scheme of miRNA regulation of important tumorigenesis processes. Further systematic analysis of co-existing miRNA-5p/3p pairs in clinical tissues is important in elucidating 5p/3p contributions to cancer pathogenesis.Electronic supplementary material
The online version of this article (doi:10.1186/s12929-014-0095-x) contains supplementary material, which is available to authorized users. 相似文献5.
18S rRNA data indicate that Aschelminthes are polyphyletic in origin and consist of at least three distinct clades 总被引:7,自引:1,他引:6
Winnepenninckx B; Backeljau T; Mackey LY; Brooks JM; De Wachter R; Kumar S; Garey JR 《Molecular biology and evolution》1995,12(6):1132-1137
The Aschelminthes is a collection of at least eight animal phyla,
historically grouped together because the absence of a true body cavity was
perceived as a pseudocoelom. Analyses of 18S rRNA sequences from six
Aschelminth phyla (including four previously unpublished sequences) support
polyphyly for the Aschelminthes. At least three distinct groups of
Aschelminthes were detected: the Priapulida among the protostomes, the
Rotifera-Acanthocephala as a sister group to the protostomes, and the
Nematoda as a basal group to the triploblastic Eumetazoa.
相似文献
6.
Chimpanzee fetal G gamma and A gamma globin gene nucleotide sequences provide further evidence of gene conversions in hominine evolution 总被引:5,自引:0,他引:5
The fetal globin genes G gamma and A gamma from one chromosome of a
chimpanzee (Pan troglodytes) were sequenced and found to be closely similar
to the corresponding genes of man and the gorilla. These genes contain
identical promoter and termination signals and have exons 1 and 2 separated
by the conserved short intron 1 (122 bp) and exons 2 and 3 separated by the
more rapidly evolving, larger intron 2 (893 bp and 887 bp in chimpanzee G
gamma and A gamma, respectively). Each intron 2 has a stretch of simple
sequence DNA (TG)n serving possibly as a "hot spot" for recombination. The
two chimpanzee genes encode polypeptide chains that differ only at position
136 (glycine in G gamma and alanine in A gamma) and that are identical to
the corresponding human chains, which have aspartic acid at position 73 and
lysine at 104 in contrast to glycine and arginine at these respective
positions of the gorilla A gamma chain. Phylogenetic analysis by the
parsimony method revealed four silent (synonymous) base substitutions in
evolutionary descent of the chimpanzee G gamma and A gamma codons and none
in the human and gorilla codons. These Homininae (Pan, Homo, Gorilla)
coding sequences evolved at one-tenth the average mammalian rate for
nonsynonymous and one-fourth that for synonymous substitutions. Three
sequence regions that were affected by gene conversions between chimpanzee
G gamma and A gamma loci were identified: one extended 3' of the hot spot
with G gamma replaced by the A gamma sequence, another extended 5' of the
hot spot with A gamma replaced by G gamma, and the third conversion
extended from the 5' flanking to the 5' end of intron 2, with G gamma
replaced here by the A gamma sequence. A conversion similar to this third
one has occurred independently in the descent of the gorilla genes. The
four previously identified conversions, labeled C1-C4 (Scott et al. 1984),
were substantiated with the addition of the chimpanzee genes to our
analysis (C1 being shared by all three hominines and C2, C3, and C4 being
found only in humans). Thus, the fetal genes from all three of these
hominine species have been active in gene conversions during the descent of
each species.
相似文献
7.
Ekwere T Ifon Alan LY Pang Warren Johnson Kathleen Cashman Sharon Zimmerman Sumitra Muralidhar Wai-Yee Chan John Casey Leonard Jason Rosenthal 《Cancer cell international》2005,5(1):19
Background
Insensitivity of advanced-stage prostate cancer to androgen ablation therapy is a serious problem in clinical practice because it is associated with aggressive progression and poor prognosis. Targeted therapeutic drug discovery efforts are thwarted by lack of adequate knowledge of gene(s) associated with prostate tumorigenesis. Therefore there is the need for studies to provide leads to targeted intervention measures. Here we propose that stable expression of U94, a tumor suppressor gene encoded by human herpesvirus 6A (HHV-6A), could alter gene expression and thereby inhibit the tumorigenicity of PC3 cell line. Microarray gene expression profiling on U94 recombinant PC3 cell line could reveal genes that would elucidate prostate cancer biology, and hopefully identify potential therapeutic targets. 相似文献8.
The effect of infection of barley with barley stripe mosaic virus on the chlorophyll, phospholipid and galactolipid content was examined in plants grown in sand culture with a range of nitrogen concentrations. The systemic yellowing and mosaic symptoms of infection were associated with a reduction in the chlorophyll and galactolipid content and an increase in the phospholipid content of leaves. The effects of the virus were not reversed by high nitrogen. The effects of virus infection are interpreted as a stress-induced phenomenon and the effects compared with those brought about by other stresses. 相似文献
9.
Background
Breast cancer cells frequently metastasize to the skeleton and induce extensive bone destruction. Cancer cells produce proteinases, including matrix metalloproteinases (MMPs) and the plasminogen activator system (PAS) which promote invasion of extracellular matrices, but whether these proteinases degrade bone matrix is unclear. To characterize the role that breast cancer cell proteinases play in bone degradation we compared the effects of three human breast cancer cell lines, MDA-MB-231, ZR-75-1 and MCF-7 with those of a normal breast epithelial cell line, HME. The cell lines were cultured atop radiolabelled matrices of either mineralized or non-mineralized bone or type I collagen, the principal organic constituent of bone. 相似文献10.
Host plant and habitat preference of the endangered Euphydryas maturna (Lepidoptera: Nymphalidae): evidence from northern Europe
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1. The aim of the present study was to evaluate host plant and habitat preferences in the Estonian populations of Euphydryas maturna, a regionally polyphagous but often locally specialised butterfly endangered in most parts of its European range. 2. Laboratory trials suggested that Fraxinus excelsior, Viburnum opulus and Melampyrum pratense are plants recognised by ovipositing females as potential hosts. These plants also supported development of the larvae, with the poorest growth performance on M. pratense. 3. Both a transect count‐based habitat occupancy analysis and a country‐wide landscape occupancy analysis revealed the abundance of F. excelsior as the primary determinant of the occurrence of E. maturna. In contrast, the occurrence of E. maturna was not associated with habitats colonised by M. pratense. 4. The results suggest that European ash, F. excelsior, is the main, if not the only, host plant of E. maturna in Estonia. The use of V. opulus cannot be excluded, although, due the relative scarcity of this plant, an important role for it as a determinant of the distribution of E. maturna is unlikely. Melampyrum pratense is not likely an alternative host of E. maturna in Estonia, which contrasts with the situation in neighbouring Finland. 5. This study adds to the evidence of geographical differences in host specialisation in melitaeine butterflies. The results imply that conservation actions should focus on securing the favourable status of the locally used host plant; the populations of F. excelsior are currently threatened by a fungal disease, ash dieback. 相似文献