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31.
Mari Moora Maarja Öpik John Davison Teele Jairus Martti Vasar Martin Zobel R. Lutz Eckstein 《Mycorrhiza》2016,26(7):735-745
While the arbuscular mycorrhizal (AM) symbiosis is known to be widespread in terrestrial ecosystems, there is growing evidence that aquatic plants also form the symbiosis. It has been suggested that symbiosis with AM fungi may represent an important adaptation for isoëtid plants growing on nutrient-poor sediments in oligotrophic lakes. In this study, we address AM fungal root colonization intensity, richness and community composition (based on small subunit (SSU) ribosomal RNA (rRNA) gene sequencing) in five populations of the isoëtid plant species Lobelia dortmanna inhabiting oligotrophic lakes in Southern Sweden. We found that the roots of L. dortmanna hosted rich AM fungal communities and about 15 % of the detected molecular taxa were previously unrecorded. AM fungal root colonization intensity and taxon richness varied along an environmental gradient, being higher in oligotrophic and lower in mesotrophic lakes. The overall phylogenetic structure of this aquatic fungal community differed from that described in terrestrial systems: The roots of L. dortmanna hosted more Archaeosporaceae and fewer Glomeraceae taxa than would be expected based on global data from terrestrial AM fungal communities. 相似文献
32.
Yasin Tülüce Pawan Tareq Ahmed Lak İsmail Koyuncu Ahmet Kılıç Mustafa Durgun Halil Özkol 《Biometals》2017,30(6):933-944
Endometrial cancer (EC) is one of the most common types of gynecologic cancer of the female genital tract; it considered being the fourth leading death factor among other types of cancer. Therefore, developing new anti-cancer agents are crucial for cancer treatment. Based on the potential of Schiff based complexes for the induction of apoptosis, Schiff base compounds, and their metal complexes displayed excellent anticancer properties. In this current study, antiproliferative activity of [L(BF2)2] as a novel binuclear boron-fluoride complex was examined to preliminary research in eight different cell lines, HELA, DU-145, PC3, DLD-1, ECC-1, PNT1-A, HT-29, and MCF-7, it was found to have a potent, suppressive effect on human endometrial adenocarcinoma cell line ECC-1. Based on this data, later investigated its apoptotic, cytotoxic, and genotoxic properties on human endometrial adenocarcinoma cell line ECC-1 in different concentrations. Apoptotic and cytotoxic tests such as single cell gel electrophoresis assay (comet assay), DNA fragmentation laddering, acridine orange test for DNA damage, and ELISA for apoptotic measurement was performed. We also gauged the oxidative status by evaluating total antioxidant status (TAS) and total oxidant status (TOS). Oxidative stress index (OSI) was calculated too. As a result [L(BF2)2] has been found to have a marvelous effect on ECC-1 cells, especially in damaging their DNA and cause a series of reactions lead to apoptosis. Taken together, it suggests that the [L(BF2)2] complex can induce the apoptotic pathway of endometrial cancer cells and is a possible candidate for future cancer treatment studies. 相似文献
33.
34.
Burcu Erbaykent Tepedelen Mehmet Korkmaz Ertugrul Tatlisumak Elgin Türköz Uluer Ercüment Ölmez İsmail Değerli Elif Soya Sevinç İnan 《Biological trace element research》2017,178(2):210-217
Evidences about the preventive and therapeutic effects of boron compounds on cancer have been increasing in the last years. Although calcium fructoborate (CaFB) is used as a nutritional supplement, data about its preventive and therapeutic effects on neoplastic transformations are limited. In the present study, the various concentrations of CaFB were applied to the MDA-MB-231 metastatic breast cancer cell line. First, we examined the cytotoxic effect and IC50 value of CaFB by MTT assay. For the evaluation of the DNA damage, apoptosis and metastatic potential, expression levels of ATM, pATM, PARP, p53, p-p53, caspase-3, caspase-9, and VEGF were investigated by using immunoblotting and immunohistochemical methods. Cell viability was significantly reduced at 50 μM CaFB treatment. pATM, p-p53, and caspase-9 levels increased significantly in all groups; furthermore, there was approximately 12.5-, 2.4-, and 10.7-fold increase, respectively, for 100 μM CaFB treatment. ATM and p53 levels did not change with CaFB treatment, but PARP levels significantly 2.5-fold decreased. While VEGF immunoreactivity decreased in all groups, significant increase in caspase-3 immunoreactivity was observed only in the group treated with 50 μM CaFB (p < 0,001). Our results imply that CaFB may have therapeutic potential as well as preventive benefits in cancer. 相似文献
35.
Gibberellic acid (GA3) is a very potent hormone whose natural occurrence in plants controls their development. Cadmium is a particularly dangerous
pollutant due to its high toxicity and great solubility in water. In this study, the effect of GA3 on Allium sativum root tip cells was investigated in the presence of cadmium. A. sativum root tip cells were exposed to CdNO3 (50, 100, 200 μM), GA3 (10-3 M), both CdNO3 and GA3. Cytogenetic analyses were performed as micronucleus (MN) assay and mitotic index (MI). Lipid peroxidation analysis was also
performed in A. sativum root tip cells for determination of membrane damage. MN exhibited a dose-dependent increase in Cd treatments in A. sativum. GA3 significantly reduced the effect of Cd on the MN frequency. MN was observed in GA3 and GA3 + 50 μm Cd treatments at very low frequency. MI slightly decreased in GA3 and GA3 + Cd treatments. MI decreased more in high concentrations of Cd than combined GA3 + Cd treatments. The high concentrations of cadmium induce MN, lipid peroxidation and lead to genotoxicity in A. sativum. Current work reveals that the effect of Cd on genotoxicity can be partially restored with GA3 application. 相似文献
36.
Mozaffari F Lindemalm C Choudhury A Granstam-Björneklett H Lekander M Nilsson B Ojutkangas ML Osterborg A Bergkvist L Mellstedt H 《Cancer immunology, immunotherapy : CII》2009,58(1):111-120
Immunotherapy is being increasingly utilized for adjuvant treatment for breast cancer (BC). We have previously described immune
functions during primary therapy for BC. The present study describes immune recovery patterns during long-term, unmaintained
follow-up after completion of adjuvant therapy.A group of patients with primary BC had been treated with adjuvant radio-chemotherapy
(RT + CT) 5-fluorouracil, epirubicin and cyclophosphamide (FEC) (n = 21) and another group with radiotherapy (RT) (n = 20) alone. Immunological testing of NK and T-cell functions was performed initially at the end of adjuvant treatment and
repeated after 2, 6 and 12 months. NK cell cytotoxicity was significantly higher (P < 0.05) at all time-points in patients than in age-matched controls and did not differ between the two treatments groups
during one year observation. In contrast, lower numbers of CD4 T-cells and lower expression of CD28 on T-cells was observed
particularly in RT + CT patients and did not normalize during the observation period. The numbers of Treg cells (CD4+CD25high) were low in the RT + CT group during follow-up, as well as expression of TCRξ, Zap70, p56lck, P59fyn and PI3 k in CD4+ cells. In contrast, expression of intracellular cytokines (IFN-γ, IL-2, IL-4) in CD4 and CD8 T cells were significantly higher
in RT + CT patients than in the RT group and the difference increased during follow-up. In conclusion, NK-cell cytotoxicity
increased during unmaintained long-term follow-up whereas CD4 and regulatory T cells as well as signal transduction molecules
remained low following adjuvant radio-chemotherapy. 相似文献
37.
Assessing the use of genomic DNA as a predictor of the maximum absorbance wavelength of avian SWS1 opsin visual pigments 总被引:1,自引:1,他引:0
Anders Ödeen Nathan S. Hart Olle Håstad 《Journal of comparative physiology. A, Neuroethology, sensory, neural, and behavioral physiology》2009,195(2):167-173
Recently, in vitro mutation studies have made it possible to predict the wavelengths of maximum absorbance (λmax) of avian UV/violet sensitive visual pigments (SWS1) from the identity of a few key amino acid residues in the opsin gene.
Given that the absorbance spectrum of a cone’s visual pigment and of its pigmented oil droplet can be predicted from just
the λmax, it may become possible to predict the entire spectral sensitivity of a bird using genetic samples from live birds or museum
specimens. However, whilst this concept is attractive, it must be validated to assess the reliability of the predictions of
λmax from opsin amino acid sequences. In this paper, we have obtained partial sequences covering three of the known spectral tuning
sites in the SWS1 opsin and predicted λmax of all bird species for which the spectral absorbance has been measured using microspectrophotometry. Our results validate
the use of molecular data from genomic DNA to predict the gross differences in λmax between the violet- and ultraviolet-sensitive subtypes of SWS1 opsin. Additionally, we demonstrate that a bird, the bobolink
Dolichonyx oryzivorus L., can have more than one SWS1 visual pigment in its retina. 相似文献
38.
Fawzeia H. Elmhalli Katinka Pålsson Jan Örberg Thomas G. T. Jaenson 《Experimental & applied acarology》2009,48(3):251-262
The toxicity of para-menthane-3,8-diol (PMD), the main arthropod-repellent compound in the oil of the lemon eucalyptus, Corymbia citriodora, was evaluated against nymphs of Ixodes ricinus using five methods (A–E) of a contact toxicity bioassay. Mortality rates were estimated by recording numbers of dead nymphs
at 30 min intervals during the first 5 h after the start of exposure and at longer intervals thereafter. The mortality rate
increased with increasing concentration of PMD and duration of exposure with a distinct effect after 3.5 h. From the results
obtained by methods A, C and E, the LC50 range was 0.035–0.037 mg PMD/cm2 and the LC95 range was 0.095–0.097 mg PMD/cm2 at 4 h of exposure; the LT50 range was 2.1–2.8 h and the LT95 range was 3.9–4.2 h at 0.1 mg PMD/cm2. To determine the duration of toxic activity of PMD, different concentrations (0.002, 0.01, 0.1 mg PMD/cm2) were tested and mortality was recorded at each concentration after 1 h; thereafter new ticks were tested. This test revealed
that the lethal activity of PMD remained for 24 h but appeared absent after 48 h. The overall results show that PMD is toxic
to nymphs of I. ricinus and may be useful for tick control. 相似文献
39.
Theoretical studies claim that if co-occurring species have very different mobilities this will result in greater small-scale
species richness, but empirical evidence is still lacking. We measured horizontal vegetative mobility (VM) of 48 herbaceous
understory species and estimated small-scale species richness in early and late successional boreonemoral herb-rich coniferous
forests in central Estonia. VM of erosulate growth forms was significantly higher than that of hemi-rosette and rosette growth
forms. Erosulate species exhibited higher mobility in young stands, but their relative and total cover was considerably higher
in old stands. Local plant richness (in 1 × 1 m plots) correlated positively with the variability of VM of species in a plot—larger
differences in VM resulted in a higher number of coexisting species. Our results thus suggest that species differences in
VM can contribute to small-scale coexistence by providing different ways to colonise empty space.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
40.