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651.
Kaya İsa Avcı Çığır Biray Şahin Fetih Furkan Özateş Neslihan Pınar Sezgin Baha Kurt Cansu Çalışkan Bilgen Cem Kirazlı Tayfun 《Molecular biology reports》2020,47(8):6127-6133
Molecular Biology Reports - Etiopathogenesis of acquired and congenital cholesteatoma is still unclear. The clinical behavior of adult acquired, pediatric acquired and congenital cholesteatomas... 相似文献
652.
Assoc. Prof. Gülnur Ekşi Bona Prof. Dr. Gülşen Akalın Çiftçi Prof. Dr. Betül Demirci Prof. Dr. Nur Münevver Pınar Assist. Prof. Aydan Acar Şahin Assoc. Prof. Mine Koçyiğit Assoc. Prof. Mehmet Bona Prof. Dr. Ayşe Mine Gençler Özkan 《化学与生物多样性》2023,20(5):e202201194
Garlic and onions are used as food and for medicinal purposes worldwide. Allium L. species are rich in bioactive organosulphur compounds that exhibit many biological activities like anticancer, antimicrobial, antihypertensive, antidiabetic activities. In this study, macro- and micromorphological characteristics of four Allium taxa were examined and the results suggested that A. callimischon subsp. haemostictum was the outgroup to sect. Cupanioscordum. Also, for the genus Allium, which is a taxonomically difficult genus, the hypothesis that chemical content and bioactivity can also be used taxonomically in addition to micro and macromorphological characters has been questioned. The bulb extract was analyzed to determine their volatile compositions and anticancer activities against human breast cancer, human cervical cancer, and rat glioma cells for the first time in the literature. To detect the volatiles, the Head Space-Solid Phase Micro Extraction method was used followed by Gas Chromatography-Mass Spectrometry. The main compounds were found as dimethyl disulfide that (36.9 %, 63.8 %, 81.9 %, 12.2 %) and methyl (methylthio)-methyl disulfide (10.8 %, 6.9 %, 14.9 %, 60.0 %) for A. peroninianum, A. hirtovaginatum and A. callidyction, respectively. Additionally, methyl-trans-propenyl disulfide is detected for A. peroniniaum (36 %). As a result, all extracts have shown significant efficacy against MCF-7 cells depending on applied concentrations. The treatment of MCF-7 cells for 24 h with 10, 50, 200, or 400 μg/mL ethanolic bulb extract of four Allium species resulted in DNA synthesis inhibition. Survival rates for A. peroninianum was 51.3 %, 49.7 %, 42.2 %, 42.0 %, for A. callimischon subsp. haemostictum 62.5 %, 63.0 %, 23.2 %, 22 %, for A. hirtovaginatum 52.9 %, 42.2 %, 42.4 %, 39.9 %, for A. callidyction 51.8 %, 43.2 %, 39.1 %, 31.3 %, for cisplatin 59.6 %, 59.9 %, 50,9 %, 48.2 %, respectively. Moreover, taxonomic evaluation according to biochemical compounds and bioactivities is almost in agreement with that made according to micro and macromorphological characters. 相似文献
653.
Impact of superparasitism time intervals on progeny survival and fitness of an egg parasitoid 下载免费PDF全文
JEAN‐FRANÇOIS DUVAL JACQUES BRODEUR JOSÉE DOYON GUY BOIVIN 《Ecological Entomology》2018,43(3):310-317
1.Superparasitism influences the fitness of female parasitoids and their progeny, and increasing time interval between oviposition bouts generally reduces survival probabilities of the second clutch. However, the timing of superparasitism may, under certain conditions, favour the second clutch. 2. This study investigated the effects of superparasitism time intervals on survival and fitness of both clutches, allowing the egg parasitoid Trichogramma euproctidis to parasitise previously parasitised Ephestia kuehniella host eggs at different time intervals. 3. In short intervals (0–1 h), a significant advantage was found for the second clutch over the first clutch (93.1% survival). In contrast, the second clutch was outcompeted by the first clutch in 17–19 h and 27–29 h intervals. Females deposited their eggs into larvae (intraspecific hyperparasitism) in a 39–41 h interval with a probability of survival of 57.1%. Females mostly refused to hyperparasitise pupae (~80% rejection at 124–126 h), and when they did, their progeny never survived. 4. Hyperparasitism significantly increased parasitoid mortality in both clutches from less than 20% (superparasitism only) to over 35%. 5. Except on newly laid eggs (0–1 h), superparasiting females were frequently observed attempting to stab immatures of all stages (from 36.4% to 89.4% of all ovipositions depending on treatment), but infanticide only appeared to succeed on larvae (39–41 h). 6. When the second clutch survived, emerging parasitoids were smaller than control individuals, probably due to resource depletion. 7. These results suggest that T. euproctidis females can detect that a host has been previously parasitised but they cannot perceive superparasitism time intervals. 相似文献
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Single-chain variable fragment (scFv) antibodies have great potential for a range of applications including as diagnostic and therapeutic agents. However, production of scFvs is challenging because proper folding and activity depend on the formation of two intrachain disulfide bonds that do not readily form in the cytoplasm of living cells. Functional expression in bacteria therefore involves targeting to the more oxidizing periplasm, but yields in this compartment can be limiting due to secretion bottlenecks and the relatively small volume compared to the cytoplasm. In the present study, we evaluated an anti-HER2 scFv, which is specific for human epidermal growth receptor 2 (HER2) overexpressed in breast cancer, for functional expression in the cytoplasm of Escherichia coli strains BL21(DE3) and SHuffle T7 Express, the latter of which is genetically engineered for cytoplasmic disulfide bond formation. Specifically, we observed much greater solubility and binding activity with SHuffle T7 Express cells, which likely resulted from the more oxidative cytoplasm in this strain background. We also found that SHuffle T7 Express cells were capable of supporting high-level soluble production of anti-HER2 scFvs with intact disulfide bonds independent of variable domain orientation, providing further evidence that SHuffle T7 Express is a promising host for laboratory and preparative expression of functional scFv antibodies. 相似文献
657.
Ulku Karaman Tuncay ?elik Tugba Raika Kiran Cemil Colak Nilgun Ulfet Daldal 《The Korean journal of parasitology》2008,46(4):293-295
The aim of this study was to investigate the difference in the serum malondialdehyde (MDA), glutathione (GSH), and nitric oxide (NO) levels between normal and T. gondii-infected patients. To this end, MDA, GSH, and NO levels in the sera of 37 seropositive patients and 40 participants in the control group were evaluated. In Toxoplasma ELISA, IgG results of the patient group were 1,013.0 ± 543.8 in optical density (mean ± SD). A statistically significant difference was found between patients and the control group in terms of MDA, GSH, and NO levels. A decrease in GSH activity was detected, while MDA and NO levels increased significantly. Consequently, it is suggested that the use of antioxidant vitamins in addition to a parasite treatment shall prove useful. The high infection vs control ratio of MDA and NO levels probably suggests the occurrence as a mechanism of tissue damage in cases of chronic toxoplasmosis. Moreover, it is recommended that the patient levels of MDA, GSH, and NO should be evaluated in toxoplasmosis. 相似文献
658.
Emre Menteşe Hakan Bektaş Bahar Bilgin Sokmen Mustafa Emirik Demet Çakır Bahittin Kahveci 《Bioorganic & medicinal chemistry letters》2017,27(13):3014-3018
A new series of benzimidazole compounds including hydrazinecarbothioamide, 1,2,4-triazole, 1,3,4-oxadiazole and imine function were synthesized starting from 5,6-dichloro-2-cyclopropyl-1H-benzimidazole. All of the benzimidazole derivatives exhibited good urease inhibitor activity. Compound 6a proved to be the most potent showing an enzyme inhibitory activity with an IC50 = 0.06 µM. Molecular docking studies were also conducted on enzyme extracted from Jack bean urease to identify the binding mode of the newly synthesized compounds. 相似文献
659.
Imen Hamed Oya Işık Burcu Ak Çimen Leyla Uslu Ebru Kafkas Mozhgan Zarifikhosroshahi 《Plant biosystems》2021,155(1):179-187
Abstract Growth and production of carotenoid in three Dunaliella species (Dunaliella salina (Dunal) Teodoresco, Dunaliella bardawil Ben-Amotz & Avron and Dunaliella sp.) were investigated using flat-plate photobioreactors in outdoor conditions with two optical paths (3?cm and 5?cm). The experiment was conducted in duplicate and lasted four weeks during which light intensity, temperature, pH and optical density were checked daily. The pigment production (total carotenoid and chlorophyll a) was monitored every two days. To induce an additional stress besides temperature and light intensity, two different salt concentrations were used, i.e. 6% and 8% NaCl. The highest growth in all treatment groups was noticed for Dunaliella sp. followed by D. bardawil and D. salina. D. salina produced a higher content of carotenoid concentrations corresponding to 5?cm/8% and 5?cm/6% groups; 779.102?±?0.434?μg.mL?1 and 694.326?±?0.098?μg.mL?1 were registered at the end of the experiment. The same species had also greater content of β-carotene. 相似文献
660.
Bee venom is a natural mixture and candidate anti-cancer agent with selective cytotoxic effect on some cancer cells. However, the cellular mechanisms of how bee venom selectively targets cancer cells remain elusive. The aim of this study was to reveal the genotoxic effect of bee venom in concordance with the location of β-actin protein throughout the nucleus or/and cytoplasm. For this aim, the level of H2AX phosphorylation (γH2AX) and intracellular location of β-actin were assessed by immunofluorescence in liver (HEPG2) and metastatic breast (MDA-MB-231) cancer cell lines compared to normal fibroblasts (NIH3T3) after bee venom treatment. Colocalisation profiles of γH2AX and β-actin in each cell line were also analysed. The results showed that the levels of γH2AX staining decreased in normal cells but increased in cancer cells. The majority of β-actin was localised within the cytoplasm of normal cells after bee venom treatment, but it was mostly accumulated within the nucleus in cancer cells. Colocalisation of β-actin and γH2AX both in nucleus and cytoplasm was induced in each cancer cell by different patterns. The results showed that normal and cancerous cells had different responses against bee venom, and suggested that bee venom induced a cellular response by the interaction between γH2AX and β-actin. 相似文献