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101.
The chemical composition of the essential oils of Eryngium campestre, E. thorifolium, and E. creticum (Apiaceae), growing in the Aegean region of Turkey (Mount Sandras, Denizli), was determined by direct thermal desorption (DTD)-GC/MS analyses. A total of 49 components were identified in the oils, α-pinene and hexanal being the major compounds. The three essential oils were also tested for their inhibitory activity of nine different methicillin-resistant Staphylococcus aureus (MRSA) strains by the agar disc diffusion method. The anti-MRSA activity of E. thorifolium oil, the most active of the three oils, was comparable with those of the reference antibiotic vancomycin and oregano oil, although somewhat lower. 相似文献
102.
Suey van Baarle Ilkay Nazli Celik Karan Gautam Kaval Marc Bramkamp Leendert W. Hamoen Sven Halbedel 《Journal of bacteriology》2013,195(5):1012-1021
DivIVA proteins are curvature-sensitive membrane binding proteins that recruit other proteins to the poles and the division septum. They consist of a conserved N-terminal lipid binding domain fused to a less conserved C-terminal domain. DivIVA homologues interact with different proteins involved in cell division, chromosome segregation, genetic competence, or cell wall synthesis. It is unknown how DivIVA interacts with these proteins, and we used the interaction of Bacillus subtilis DivIVA with MinJ and RacA to investigate this. MinJ is a transmembrane protein controlling division site selection, and the DNA-binding protein RacA is crucial for chromosome segregation during sporulation. Initial bacterial two-hybrid experiments revealed that the C terminus of DivIVA appears to be important for recruiting both proteins. However, the interpretation of these results is limited since it appeared that C-terminal truncations also interfere with DivIVA oligomerization. Therefore, a chimera approach was followed, making use of the fact that Listeria monocytogenes DivIVA shows normal polar localization but is not biologically active when expressed in B. subtilis. Complementation experiments with different chimeras of B. subtilis and L. monocytogenes DivIVA suggest that MinJ and RacA bind to separate DivIVA domains. Fluorescence microscopy of green fluorescent protein-tagged RacA and MinJ corroborated this conclusion and suggests that MinJ recruitment operates via the N-terminal lipid binding domain, whereas RacA interacts with the C-terminal domain. We speculate that this difference is related to the cellular compartments in which MinJ and RacA are active: the cell membrane and the cytoplasm, respectively. 相似文献
103.
Oguz Ozturk Emel Canbay Ozlem T. Kahraman M. Fatih Seyhan Fatih Aydogan Varol Celik Cihan Uras 《Molecular biology reports》2013,40(2):1813-1818
Although HER2/PTEN pathway is commonly disrupted in cancer, association of HER2 and PTEN polymorphisms with breast cancer (BC) remains controversial. We investigated the HER2 Ile655 Val and PTEN IVS4 polymorphisms in patients with BC in Turkish population. HER2 Ile655Val (rs 1136201) and PTEN IVS4 (rs 3830675) polymorphisms were determined using polymerase chain reaction-based restriction fragment length polymorphism (PCR–RFLP) in blood samples of 118 BC patients and 118 age-matched healthy controls. We found that the frequency of the Ile/Val genotype of HER2 Ile655Val gene was significantly higher in BC patients (p < 0.009; OR: 1,983 95 % CI: 1.181—3.328). The presence of ATCTT insertion (+/+) genotype at downstream of exon 4 in intron 4 of PTEN IVS4 gene was also associated with 1.83 fold decreased risk of BC development (p < 0.033; OR: 1.83, 95 % CI: 1.11—3.03). Analysis on clinico-pathological parameters showed neither HER2 Ile655Val nor PTEN IVS4 genotypes were not associated with any of the variables (p > 0.05).In conclusion, our findings suggest that the Ile/Val genotype of HER2 and ATCTT insertion (+/+) genotype of PTEN IVS4 gene may play an important role as genetic markers for breast cancer risk, but both genes genotypes may not be useful for predicting tumor prognosis in Turkish population. 相似文献
104.
Simone Carradori Celeste De Monte Melissa D’Ascenzio Daniela Secci Gulsah Celik Mariangela Ceruso Daniela Vullo Andrea Scozzafava Claudiu T. Supuran 《Bioorganic & medicinal chemistry letters》2013,23(24):6759-6763
Salen and tetrahydrosalen derivatives possess metal-chelating properties and have been used as ligands in organic synthesis and as scaffolds for developing therapeutic agents. Fourteen such compounds were synthesized in order to explore their ability to inhibit the zinc enzyme carbonic anhydrase (CA, EC 4.2.1.1). Human (h) isoforms hCA I, hCA II, hCA IX and hCA XII were included in the investigation. Several aliphatic and aromatic spacers were introduced between the two chelating groups from salen/tetrahydrosalen in order to explore a diverse chemical space for designing CA inhibitors, which incorporate both phenol and polyamine fragments in their molecule. Some of these compounds showed CA inhibitory activity in the low micromolar–nanomolar range and a pronounced selectivity for inhibiting an isoform over-expressed in hypoxic tumors, hCA XII, over hCA I, II and IX. 相似文献
105.
The occurrence of Sciadicleithrum variabilum on the gills of discus Symphysodon aequifasciatus larvae 7 days after hatching is reported for the first time. This suggests that altricial larvae are susceptible to Monogenea following gill differentiation and before complete yolk resorption. 相似文献
106.
OBJECTIVES: To investigate whether there is lymphocyte deoxyribonucleic acid (DNA) damage in patients with cardiac syndrome X (CSX), and its relation with total antioxidant status (TAS), inflammation and ischemia. METHODS: Twenty-three patients with CSX, 21 patients with non-CSX (NCSX) and 20 healthy volunteers were included in the study. Lymphocyte DNA damage (Arbitrary Unit) was assessed by alkaline single cell electrophoresis (comet) assay in peripheral lymphocyte, and plasma levels of TAS (mmol Trolox equiv./l) were determined using a novel automated measurement method. High sensitive C-reactive protein (hsCRP) and other biochemical parameters were measured from all subjects. Treadmill exercise test and coronary angiography were performed to CSX and NCSX groups. RESULTS: Lymphocyte DNA damage was increased in patients with CSX compared with NCSX and control group (p<0.001, for both). Also, TAS was decreased, and hsCRP was increased in CSX compared with NCSX and control group (p<0.001, for all). Lymphocyte DNA damage was correlated with magnitude of ST depression (p=0.034), hsCRP (p=0.001), TAS (p<0.001) and presence of diabetes (p=0.022) in bivariate analysis. In multiple linear regression analysis, lymphocyte DNA damage was correlated with only TAS (beta=-0.413, p=0.017) and hsCRP (beta=0.414, p=0.006). CONCLUSION: Lymphocyte DNA damage was increased in patients with CSX. The increase in lymphocyte DNA damage may be related with increased oxidative stress and inflammation in patients with CSX. 相似文献
107.
108.
Celik S Gorur S Aslantas O Erdogan S Ocak S Hakverdi S 《Molecular and cellular biochemistry》2007,297(1-2):131-138
Although oxidative damage is known to be involved in inflammatory-mediated tissue destruction, modulation of oxygen free radical
production represents a new approach to the treatment of inflammatory diseases. Caffeic acid phenethyl ester (CAPE), an active
component of propolis from honeybee hives, has antioxidant, anti-inflammatory and antibacterial properties. For that reason,
we aimed to investigate the efficiency of CAPE administration in preventing oxidative damage in pyelonephritis (PYN) caused
by Escherichia coli. In this study, 35 Wistar rats were grouped as follows: control, PYN 24 h, PYN 48 h, PYN 72 h, CAPE 24 h, CAPE 48 h and CAPE
72 h. E. coli (1 × 109 c.f.u.) were inoculated into the rats in both PYN and CAPE groups via urethral catheterization. Ten μM/kg-body weight CAPE
was injected to the rats in all CAPE groups 24 h before E. coli infection, and injections were repeated at 24-h intervals. Rats were sacrificed 24 h, 48 h and 72 h after infection in both
PYN and CAPE groups. Malondialdehyde (MDA) and nitric oxide (NO) levels were significantly increased in kidneys of PYN groups.
The activities of the antioxidant enzymes, catalase (CAT), superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), and
xanthine oxidase (XO) were also elevated by E. coli. However, CAPE administration reduced MDA and NO levels, as well as XO activity, although it increased SOD and GSH-Px activities.
Histopathological examination showed that CAPE reduced the inflammation grade induced by E. coli. In conclusion, CAPE administrations decrease the oxidative damage occurring in PYN and therefore could be used for medical
management of bacterial nephropathy. 相似文献
109.
In the present study, chromosomal aberrations (CAs) and micronucleus (MN) levels in the lymphocytes from 60 male individuals
consisting of 40 habitues of Maras powder (a kind of smokeless tobacco) and 20 unexposed subjects were determined to investigate
the possible inducing effect of Maras powder. The consumers of Maras powder had no exposure to any other known mutagens or
toxicants. The mean exposure period to Maras powder was 12.25 ± 0.93 years (range 3–22). Data obtained from microscopic examination
of the slides was analyzed using SPSS (10.0) software package. Mean frequency of CA and MN was found to be significantly higher
in Maras powder consumers as compared to controls. Similarly, there was a significant elevation in the level of aberrant cells
(Ab.Cells) with CAs and binucleated cells with MN (BNMN) in habitues. Spearman’s rho correlation analysis indicated a significant
increase in the frequency of CA and MN with increase in both age and years of exposure in consumers. Our finding of a significant
elevation of CA and MN frequencies in peripheral lymphocytes from smokeless tobacco consumers demonstrated a potential cytogenetic
hazard associated with Maras powder exposure.
The text was submitted by the authors in English. 相似文献
110.
BioMetals - Mitochondrial iron transporter (MIT) genes are essential for mitochondrial acquisition/import of iron and vital to proper functioning of mitochondria. Unlike other organisms, research... 相似文献