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排序方式: 共有247条查询结果,搜索用时 0 毫秒
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H. Yasemin Yenilmez Nazli Farajzadeh Nilgün Güler Kuşçulu Dilek Bahar Sadin Özdemir Gülşah Tollu Mithat Güllü Zehra Altuntaş Bayır 《化学与生物多样性》2023,20(4):e202201167
In this study, three new axially disubstituted silicon phthalocyanines ( SiPc1–3 ) and their quaternized phthalocyanine derivatives ( QSiPc1–3 ) were prepared and characterized. The biological properties (antioxidant, antimicrobial, antibiofilm, and microbial cell viability activities) of the water-soluble silicon phthalocyanines were examined, as well. A 1 % DMSO diluted with pure water was used as a solvent in biological activity studies. All the compounds exhibited high antioxidant activity. They displayed efficient antimicrobial and antimicrobial photodynamic therapeutic properties against various microorganisms, especially Gram (+) bacteria. Additionally, they demonstrated high antibiofilm activities against S. aureus and P. aeruginosa. In addition, 100 % bacterial reduction was obtained for all the studied phthalocyanines against E. coli viable cells. Besides, the DNA cleavage and binding features of compounds ( QSiPc1–3 ) were studied using pBR322 DNA and CT-DNA, respectively. Furthermore, the human topoisomerase I enzyme inhibition activities of compounds QSiPc1 – 3 were studied. Anticancer properties of the water-soluble compounds were investigated using cell proliferation MTT assay. They exhibited anticarcinogenic activity against the human colon cancer cell line (DLD-1). Compounds QSiPc1 and QSiPc3 displayed a high anticarcinogenic effect on the DLD-1 cell line. The obtained results indicated that all the studied compounds may be effective biological agents and anticancer drugs after further investigations. 相似文献
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Population density, fecundity andreproduction period of Artemia sp. in TuzLake, Turkey, beside environmental factors, such as oxygen,temperature, salinity, pH and electrical conductivity werestudied during 1993 and 1994.Artemia sp. occurred at two stations at the coast.Overwintering cysts hatched in early May, when the population was composed of 90% metanauplii (93%at Y4 and 99% at Y5) and few adult females. Peak abundanceoccurred in late May, at 106to 114 ind.m–3. 相似文献
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Bogan Mustafa Al Behcet Kul Seval Zengin Suat Oktay Murat Sabak Mustafa Gümüşboğa Hasan Bayram Hasan 《International journal of biometeorology》2021,65(10):1733-1739
International Journal of Biometeorology - Epidemiological studies have suggested an association between particulate air pollution, increased temperatures, and morbidity related to pregnancy... 相似文献
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The scope of this study is to achieve carrier-bound immobilization of catalase onto magnetic particles (Fe3O4 and Fe2O3NiO2 · H2O) to specify the optimum conditions of immobilization. Removal of H2O2 and the properties of immobilized sets were also investigated. To that end, adsorption and then cross-linking methods onto magnetic particles were performed. The optimum immobilization conditions were found for catalase: immobilization time (15 min for Fe3O4; 10 min for Fe2O3NiO2 · H2O), the initial enzyme concentration (1 mg/mL), amount of magnetic particles (25 mg), and glutaraldehyde concentration (3%). The activity reaction conditions (optimum temperature, optimum pH, pH stability, thermal stability, operational stability, and reusability) were characterized. Also kinetic parameters were calculated by Lineweaver–Burk plots. The optimum pH values were found to be 7.0, 7.0, and 8.0 for free enzyme, Fe3O4-immobilized catalases, and Fe2O3NiO2 · H2O-immobilized catalases, respectively. All immobilized catalase systems displayed the optimum temperature between 25 and 35°C. Reusability studies showed that Fe3O4-immobilized catalase can be used 11 times with 50% loss in original activity, while Fe2O3NiO2 · H2O-immobilized catalase lost 67% of activity after the same number of uses. Furthermore, immobilized catalase systems exhibited improved thermal and pH stability. The results transparently indicate that it is possible to have binding between enzyme and magnetic nanoparticles. 相似文献
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Anderson Ayuk Agbor A. Yasemin Göksenin Kimberly G. LeCompte Samuel H. Hans Zachary F. Pursell 《DNA Repair》2013,12(11):954-963
Mutations in human DNA polymerase (Pol) ?, one of three eukaryotic Pols required for DNA replication, have recently been found associated with an ultramutator phenotype in tumors from somatic colorectal and endometrial cancers and in a familial colorectal cancer. Possibly, Pol ? mutations reduce the accuracy of DNA synthesis, thereby increasing the mutational burden and contributing to tumor development. To test this possibility in vivo, we characterized an active site mutant allele of human Pol ? that exhibits a strong mutator phenotype in vitro when the proofreading exonuclease activity of the enzyme is inactive. This mutant has a strong bias toward mispairs opposite template pyrimidine bases, particularly T•dTTP mispairs. Expression of mutant Pol ? in human cells lacking functional mismatch repair caused an increase in mutation rate primarily due to T•dTTP mispairs. Functional mismatch repair eliminated the increased mutagenesis. The results indicate that the mutant Pol ? causes replication errors in vivo, and is at least partially dominant over the endogenous, wild type Pol ?. Since tumors from familial and somatic colorectal patients arise with Pol ? mutations in a single allele, are microsatellite stable and have a large increase in base pair substitutions, our data are consistent with a Pol ? mutation requiring additional factors to promote tumor development. 相似文献
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Köse Çınar Rugül Görgülü Yasemin Çalıyurt Okan Sönmez Bülent 《Sleep and biological rhythms》2016,14(4):387-396
Sleep and Biological Rhythms - Sleep deprivation (SD) is known to modulate inflammatory and oxidative stress markers. How these markers change over the SD period have seldom been studied in healthy... 相似文献
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Fatih Oltulu Duygu Ç. Kocatürk Yasemin Adalı Berrin Özdil Eda Açikgöz Çevik Gürel N. Ulku Karabay Yavasoğlu Huseyin Aktuğ 《Journal of cellular biochemistry》2019,120(10):18066-18076
Embryonic developmental stages and regulations have always been one of the most intriguing aspects of science. Since the cancer stem cell discovery, striking for cancer development and recurrence, embryonic stem cells and control mechanisms, as well as cancer cells and cancer stem cell control mechanisms become important research materials. It is necessary to reveal the similarities and differences between somatic and cancer cells which are formed of embryonic stem cells divisions and determinations. For this purpose, mouse embryonic stem cells (mESCs), mouse skin fibroblast cells (MSFs) and mouse lung squamous cancer cells (SqLCCs) were grown in vitro and the differences between these three cell lines signalling regulations of mechanistic target of rapamycin (mTOR) and autophagic pathways were demonstrated by immunofluorescence and real-time polymerase chain reaction. Expressional differences were clearly shown between embryonic, cancer and somatic cells that mESCs displayed higher expressional level of Atg10, Hdac1 and Cln3 which are related with autophagic regulation and Hsp4, Prkca, Rhoa and ribosomal S6 genes related with mTOR activity. LC3 and mTOR protein levels were lower in mESCs than MSFs. Thus, the mechanisms of embryonic stem cell regulation results in the formation of somatic tissues whereas that these cells may be the causative agents of cancer in any deterioration. 相似文献