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51.
Nuray Bogurcu Canan Sevimli-Gur Besra Ozmen Erdal Bedir Kemal Sami Korkmaz 《Biochemical and biophysical research communications》2011,(4):738
Endemic Alkanna cappadocica was used to isolate novel antitumor molecules from Turkish landscapes in our previous studies. In this study, deoxyalkannin (ALCAP1), β,β-dimethylacrylalkannin (ALCAP2), acetylalkannin (ALCAP3), and alkannin (ALCAP4) as well as the novel isolated compounds 5-methoxydeoxyalkannin (ALCAP5), 8-methoxydeoxyalkannin (ALCAP6), 5-methoxyacetylalkannin (ALCAP7), 5-methoxy-β,β-dimethylacrylalkannin (ALCAP8) were characterized. The topoisomerase I (topo I) inhibitory activity of ALCAPs was investigated using in vitro plasmid relaxation assay and found that ALCAP2, 3, 4 and 7 were potent inhibitors at 2–6 μM concentrations. Further, DNA damage response to ALCAP treatments was also studied by measuring the H2AX(S139) and ATM(S1981) phosphorylations. ALCAP2, 7 and 8 induced the DNA damage and apoptosis, consistently resulted in PARP cleavage at nanomolar concentrations in K562 leukemia cells. Moreover, when the free radical (ROS) generating capacity of the compounds was studied by 2′,7′-dichlorofluorescein-diacetate assay using flow cytometry, we found that a known antioxidant N-acetyl-cysteine almost completely abrogated the H2AX(S139) phosphorylations and the caspase 3 cleavage and activation. Thus, γH2AX(S139) foci formation remained higher than the control, and an increase in CHK2(T68) phosphorylation was observed by ALCAP2 and 7 treatments suggested that, these compounds can be potential therapeutics against tumor cell growth because of their unique DNA damaging abilities additional to enzyme inhibition similar to those of doxorubicin. 相似文献
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53.
Sadiye Hayta Ismail Hakki Akgun Markus Ganzera Erdal Bedir Aynur Gurel 《Plant Cell, Tissue and Organ Culture》2011,107(1):175-180
Gentiana cruciata L. (Cross gentian) is a medicinal and ornamental plant, threatened in its natural habitats. The wild root extracts of this
species are known to exhibit many curative properties. In the present study, an efficient protocol for in vitro propagation
of G. cruciata L. was developed from node culture. A semi-solidified Murashige and Skoog (MS) basal medium supplemented with 2.22 μM 6-benzyladenine
(BA), 2.46 μM indole-3-butyric acid (IBA) and sucrose (3% w/v) improved the production of multiple shoots directly from nodal
segments, providing 3.9 shoots per explants on average. The highest rooting (81.7%) was observed with half-strength MS medium
supplemented with 2.46 μM IBA. Plants with well-developed roots were transferred to pots containing turf/vermiculite mixtures
and acclimatized in plant growth chamber conditions. Acclimatized plants showed 100% survival and remained healthy. The content
of secondary metabolites in the clones was determined by HPLC, and the presence of gentiopicroside, loganic acid, swertiamarin,
and sweroside in the samples was confirmed. Gentiopicroside was found to be the major compound. 相似文献
54.
In the present study, it was aimed to investigate the influence of exogenous mammalian sex hormones (MSH) (progesterone, β-estradiol
and androsterone) on the morphological (root and shoot growth) and biochemical parameters (protein and sugar content, antioxidant
enzyme activities, and lipid peroxidation and H2O2 levels) of chickpea (Cicer arietinum L.) plants growing under control conditions. The solutions of hormones prepared at different concentrations (10−4, 10−6, 10−9, 10−12 and 10−15 M) were sprayed once on the leaves of 7-day plants. The plants were harvested on 18 days after the hormone treatment. Although
all of the hormones at the tested concentrations significantly increased plant growth, soluble protein and sugar contents,
and antioxidant enzyme activities [superoxide dismutase (SOD), peroxidase (POX) and catalase (CAT)], they decreased H2O2 content and lipid peroxidation level when compared with control plants. The activities of SOD, POX and CAT reached to the
highest levels at 10−6 M for progesterone, and 10−9 M for β-estradiol and androsterone, which maximum growth, protein and sugar contents were determined. The same concentrations
also resulted in the lowest levels for H2O2 content and lipid peroxidation. It can be interpreted that the MSH improve plant growth and development by affecting some
biochemical parameters including antioxidative system. 相似文献
55.
Ahmet Sinan SARI Emre DEMRAY Ahmet
ZTÜRK Ayen TERZ Erdal KARA
Z 《Turkish Journal of Biology》2021,45(3):301
Selective targeting of transfected mesenchymal stem cells (MSCs) carrying specific antioncogenes to the tumor was suggested as a treatment option. Bone morphogenetic protein-2 (BMP2) was shown to inhibit the proliferation and aggressiveness of osteosarcoma (OS) cells. Here, we aimed to assess the homing efficiency of intraperitoneally administered hMSCs transfected with BMP2 to the tumoral site and their effects on OS using an orthotopic xenograft murine model. Orthotopic xenograft murine model of OS in six-week-old female NOD/SCID mice using 143B cells was established. hMSCs transfected with BMP2 (BMP2+hMSC) were used. In vivo experiments performed on four groups of mice that received no treatment, or intraperitoneally administered BMP2, hMSCs, and BMP2+hMSCs. Histopathological and immunohistochemical studies were used to evaluate the pathological identification and to assess the dimensions and necrotic foci of the tumor, the features of lung metastases, and immunostaining against p27, Ki-67, and caspase-3 antibodies. The osteogenic differentiation markers BMP2, BMP4, COL1A1, OPN, OCN and PF4 evaluated using RT-PCR. The tumor dimensions in the hMSCs group were significantly higher than those of the remaining groups (p < 0.01). The number of metastatic foci in the BMP2+hMSCs group was significantly lower than those of the other groups (p < 0.01). The current results showed that the intraperitoneal route could be efficiently used for targeting hMSCs to the tumoral tissues for effective BMP2 delivery. In this study, the effects of BMP2 transfected hMSCs on human OS and metastasis were promising for achieving osteogenic differentiation and reduced metastatic process. 相似文献
56.
Oncü M Kocak A Karaoz E Darici H Savik E Gultekin F 《Biological trace element research》2007,118(3):260-268
This experiment was designed to investigate the histological and lipid peroxidation effects of chronic fluorosis on testes
tissues of first- and second-generation rats. Sixteen virgin female Wistar rats were mated with eight males (2:1) for approximately
12 h to obtain first-generation rats. Pregnant rats were divided into two groups: controls and fluoride-given group, each
of which containing five rats. Pregnant rats in the fluoride-given group were exposed to a total dose of 30 mg/l sodium fluoride
(NaF) in commercial drinking water containing 0.07 mg/l of NaF throughout the gestation and lactation periods. After the lactation
period, the young animals (first generation, F1) were exposed to the same dose of NaF in drinking water for 4 months. At the
end of the 4 months of experimental period, nine randomly chosen male rats (F1) were killed and testes tissues were taken
for histopathological and biochemical analysis. The remaining eight female rats were mated with four males (2:1) for approximately
12 h to obtain second-generation rats. Six female were identified as pregnant and treated with similarly throughout the gestation
and the lactation periods. After the lactation period, the young male animals (second generation, F2) were also treated in
the same way for 4 months. At the end of the 4 months of experimental period, nine randomly chosen male rats (F2) were killed
and testes tissues were collected for histopathological and biochemical analysis. The rats in the control group were applied
the same procedure without NaF administration. In biochemical analysis of the fluoride given F1 and F2 rats, it has been found
that plasma fluoride levels and testes thiobarbituric acid reactive substance levels were significantly increased when compared
with the control group. In F1 and F2 rats, similar histopathological changes were observed. In both groups, spermatogenesis
was severely reduced. Spermatogonia and primary spermatocytes were normal, however, there was a widespread degeneration in
other spermatogenic cell lines of the seminiferous epithelium. The histological structures of the Sertoli and interstitial
Leydig cells were normally observed. It is concluded that chronic fluorosis exposure leads to a remarkable destruction in
testes tissues of F1 and F2 rats via lipid peroxidation.
The study was carried out in Suleyman Demirel University. 相似文献
57.
The regulatory effect of melatonin on physiological,biochemical and molecular parameters in cold-stressed wheat seedlings 总被引:1,自引:0,他引:1
Hulya Turk Serkan Erdal Mucip Genisel Okkes Atici Yavuz Demir Derya Yanmis 《Plant Growth Regulation》2014,74(2):139-152
We investigated the possible mediatory role of melatonin in protecting wheat plants from cold stress. Ten-day-old wheat seedlings were pretreated with 1 mmol l?1 melatonin for 12 h and subsequently exposed to stress conditions at 5/2 °C (day/night) for 3 days. Cold stress caused serious reductions in leaf surface area, water content, and photosynthetic pigment content, whereas melatonin application attenuated these reductions. Accumulation of reactive oxygen species (ROS), including superoxide and hydrogen peroxide, was very high in cold-stressed plants and caused lipid peroxidation in membranes. Concomitantly, ROS damaged the DNA profile and negatively influenced expression and/or activity of many enzymes, including RuBisCo. When compared to controls, cold-stressed plants had higher activities of the antioxidant enzymes superoxide dismutase, guaicol peroxidase, ascorbate peroxidase, and glutathione reductase and higher levels of the antioxidant compounds total ascorbate, reduced ascorbate, total glutathione, reduced glutathione, and phenolic substances; however, this elevation could not cope with the destructive effects of cold stress. Melatonin-pretreated plants exhibited greater increases in these parameters comparison with untreated cold-stressed plants. Isozyme bands monitored in native gel and RuBisCo expression supported these changes. Also, due to the cold-induced increase in dehydroascorbate and oxidized glutathione, the corrupted redox status in the cell was ameliorated by melatonin application. Similarly, levels of the osmoprotectants total soluble protein, carbohydrate, and proline were also increased by cold stress; however, melatonin-applied seedlings had a higher content of these solutes in comparison to untreated cold-stressed plants. We suggest that melatonin can improve plant resistance to cold stress in wheat seedlings by directly scavenging ROS and by modulating redox balance and other defence mechanisms. 相似文献
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59.
Whiten A Erdal D 《Philosophical transactions of the Royal Society of London. Series B, Biological sciences》2012,367(1599):2119-2129
Hominin evolution took a remarkable pathway, as the foraging strategy extended to large mammalian prey already hunted by a guild of specialist carnivores. How was this possible for a moderately sized ape lacking the formidable anatomical adaptations of these competing 'professional hunters'? The long-standing answer that this was achieved through the elaboration of a new 'cognitive niche' reliant on intelligence and technology is compelling, yet insufficient. Here we present evidence from a diversity of sources supporting the hypothesis that a fuller answer lies in the evolution of a new socio-cognitive niche, the principal components of which include forms of cooperation, egalitarianism, mindreading (also known as 'theory of mind'), language and cultural transmission, that go far beyond the most comparable phenomena in other primates. This cognitive and behavioural complex allows a human hunter-gatherer band to function as a unique and highly competitive predatory organism. Each of these core components of the socio-cognitive niche is distinctive to humans, but primate research has increasingly identified related capacities that permit inferences about significant ancestral cognitive foundations to the five pillars of the human social cognitive niche listed earlier. The principal focus of the present study was to review and integrate this range of recent comparative discoveries. 相似文献
60.
Three new cycloartane-type triterpene glycosides were isolated from the roots of Astragalus schottianus Boiss. Their structures were established as 20(R),25-epoxy-3-O-β-d-xylopyranosyl-24-O-β-d-glucopyranosyl-3β,6α,16β,24α-tetrahydroxycycloartane (1), 20(R),25-epoxy-3-O-[β-d-glucopyranosyl(1 → 2)]-β-d-xylopyranosyl-24-O-β-d-glucopyranosyl-3β,6α,16β,24α-tetrahydroxycycloartane (2), 3-O-β-d-xylopyranosyl-3β,6α,16β,20(S),24(S),25-hexahydroxycycloartane (3) by the extensive use of 1D and 2D-NMR techniques and mass spectrometry. 相似文献