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81.
Terken Baydar Gönül Şahin Ahmet Aydïn Aşkïn Işïmer Nilgün Atakam 《Biological trace element research》1998,64(1-3):37-42
The Al content of 18 patch test allergens were measured by electrothermal atomic absorption spectrophotometry. It was found
that these preparations contained Al in various amounts. We conclude that the presence of Al in patch test allergens may interfere
with the diagnosis and evaluations of patients to whom the test is applied. 相似文献
82.
As a part of a large-scale work aimed at studying the health effects of boron (B) in residents of a country with the world’s
largest supply, developmental effects of B are presented. Spontaneous abortions, stillbirths, and congenital malformations
in addition to early infant mortality were questioned in the field by home visits. Although the number of families so far
ascertained is rather small, the rates related to spontaneous abortions and stillbirths from high B exposure vs low B exposure
subpopulations revealed no differences of significance, providing no evidence that B affects human development adversely. 相似文献
83.
Serpil Kiliç Yayla Zekiye Kocakaya Gökçe Şeker Karatoprak Selen İlgün Ahmet Ceylan 《化学与生物多样性》2023,20(1):e202200816
The present study is focused on the antimicrobial, antioxidant, cytotoxic, and DNA protective effects of methanol extract obtained from R. digitellata, R. fastigiata, R. fraxinea, and R. polymorpha species that are distributed in Turkey. The highest total phenol content was determined in R. digitellata (144.6 mgGAE/gextract), and the highest total amount of flavonoids was found in R. fastigiata (20.40 mgGAE/gextract). The content of usnic acid was determined by High-Performance Liquid Chromatography (HPLC) and the highest amount was found in R. digitellata. DPPH (1,1-diphenyl-2-picrylhydrazyl) and ABTS [2,2’-azinobis(3-ethylbenzathiazoline-6-sulfonic acid)] radical scavenging methods were used for antioxidant activity. R. fraxinea showed the highest DPPH⋅ and ABTS+⋅ scavenging activity. In addition, the DNA protective effect was investigated using pBR322 plasmid DNA, and; all studied species were found to have DNA protective effects. The antibacterial activity was investigated using the disc diffusion method, and the R. digitellata methanol extract showed the best results with a 12.35 mm zone on Proteus mirabilis. On the human lung cancer (A549) and breast cancer (MDA-MB-231) cell lines, cytotoxic activity was assessed using an MTT assay. All lichen extracts were found to have a significant cytotoxic effect on both cancer cell lines at 1000 μg/mL concentration. These results suggest that Ramalina species may be potential candidates for developing new phytopharmaceuticals and functional components. 相似文献
84.
Duygu Nur Çobanoğlu Mehmet Emin Şeker İlginç Kizilpinar Temizer Ayşegül Erdoğan 《化学与生物多样性》2023,20(3):e202201124
Bee bread is a unique natural product made by bees and good for human health. It has many bioactive molecules that can treat or prevent diseases. In this study, melissopalynological methods were used to examine five bee bread samples. Major plant sources found in bee bread were Lotus spp., Trifolium spp., and Xeranthemum spp., which are from the Fabaceae and Asteraceae families. Then, the amount of phenolic compounds and major carotenoids in bee bread (BB) samples were quantified. Gallic acid, caffeic acid, quercetin, and kaempferol were found in all BB samples, with β-carotene being the most abundant carotenoid in all but BB1. In addition, the total phenolic/flavonoid content and antioxidant activities of all BB samples were determined. Total flavonoid, total phenolic, DPPH⋅, and ABTS⋅+ values were varied between 5.6–10.00 mg GAE/g DW, 1.2–4.3 mg QE/g DW, 1.2–5.5 mg TEAC/g DW, and 2.6–15.4 mg TEAC/g DW, respectively. 相似文献
85.
Dr. Halil Şenol Dr. Mansour Ghaffari-Moghaddam Şeyma Bulut Dr. Fahri Akbaş Dr. Aytekin Köse Dr. Gülaçtı Topçu 《化学与生物多样性》2023,20(9):e202301089
Herein, new derivatives of α,β-unsaturated ketones based on oleanolic acid ( 4 a – i ) were designed, synthesized, characterized, and tested against human prostate cancer (PC3). According to the in vitro cytotoxic study, title compounds ( 4 a – i ) showed significantly lower toxicity toward healthy cells (HUVEC) in comparison with the reference drug doxorubicin. The compounds with the lowest IC50 values on PC3 cell lines were 4 b (7.785 μM), 4 c (8.869 μM), and 4 e (8.765 μM). The results of the ADME calculations showed that the drug-likeness parameters were within the defined ranges according to Lipinski's and Jorgensen's rules. For the most potent compounds 4 b , 4 c , and 4 e , a molecular docking analysis using the induced fit docking (IFD) protocol was performed against three protein targets (PARP, PI3K, and mTOR). Based on the IFD scores, compound 4 b had the highest calculated affinity for PARP1, while compound 4 c had higher affinities for mTOR and PI3K. The MM-GBSA calculations showed that the most potent compounds had high binding affinities and formed stable complexes with the protein targets. Finally, a 50 ns molecular dynamics simulation was performed to study the behavior of protein target complexes under in silico physiological conditions. 相似文献
86.
Mine İnal Güngör Kanbak Saniye Şen Fahrettin Akyüz Emine Sunal 《Free radical research》2013,47(3):211-216
In this study, plasma and red blood cell (RBC) antioxidant status and plasma lipid peroxidation were investigated in 46 hemodialysis patients. In addition, the effect of erythropoietin (EPO) and EPO-vitamin E combination therapy on plasma and RBC antioxidant status, and plasma lipid peroxidation were examined.There were 10 healthy subjects in the control group and 10 hemodialysis patients in the untreated group. The third group included 36 hemodialysis patients that were given EPO (100 U/kg) for 3 months, 3 times per week. The fourth group included 36 hemodialysis-patients from the EPO group that were given EPO at a 50% decreased dose + vitamin E (300 mg/day) for 3 months.MDA levels in the untreated group, the EPO group and the EPO + vitamin E groups were found to be higher than the control group (p<0.001, in both). Furthermore, MDA levels in both of the treatment groups were lower when compared to the untreated group (p<0.001, in both). Plasma vitamin E levels in the untreated, the EPO group and EPO + vitamin E groups were lower than the control group (p<0.001). In contrast, plasma vitamin E levels in the treatment groups were higher in comparison with the control group (p<0.05). SOD activities in the untreated, the EPO group and the EPO + vitamin E groups were found to be lower than the control group (p<0.001). SOD activities in the treatment groups were higher than the control group (p<0.001). The SOD activities in the EPO + vitamin E group increased when compared to the EPO group (p<0.001). CAT activities in the untreated, the EPO group and the EPO + vitamin E groups were found to be lower than the control group (p<0.001 in untreated and EPO groups, p<0.01 in EPO + vitamin E group). CAT activities in EPO and EPO + vitamin E groups were increased when compared to the untreated group (p<0.01).In conclusion, our findings have shown that antioxidant status decreased and lipid peroxidation increased in hemodialysis patients. EPO has an antioxidant effect on the RBC and plasma antioxidant status, and plasma lipid peroxidation. These effects were moderately increased by the combination of vitamin E and EPO. 相似文献
87.
The purpose of this study was to ascertain whether vitamin C supplementation during chronic exercise training alters rat brain
antioxidant content. Female Wistar albino rats were exercised on a treadmill for 30 min/day for 6.5 weeks and were administered
daily intraperitoneal injections of vitamin C (20 mg/kg). After the training period, chronically exercised rats showed no
significant changes in total brain thiobarbituric acid reactive substances (TBARS) levels. In contrast, rats supplemented
with vitamin C during the training period showed significantly elevated brain TBARS levels. If such results were extrapolated
to man, where vitamin supplementation is a common practice, this would indicate that vitamin C supplementation may not protect
brain tissue against exercise-induced oxidative damage, in such circumstances, this water-soluble antioxidant behaves as a
pro-oxidant. (Mol Cell Biochem xxx: 135–138, 2005) 相似文献
88.
Coşkun S Karataş F Acartürk F Olmuş H Selvi M Erbaş D 《Molecular and cellular biochemistry》2005,278(1-2):65-69
The aim of the current study was to comparatively investigate the effect of inhibition of nitric oxide (NO) production by
N-nitro-L-arginine methyl ester (L-NAME), an isoform non-specific inhibitor of nitric oxide synthase (NOS), after oral mucosal
incision on wound tissue NO levels. A standard incision was applied to the oral mucosa of rabbits. After oral mucosal incision,
rabbits were divided into five groups as follows: (1) Untreated incisional group (control); (2) Titanium (Ti) implanted group;
(3) Ti + Polyethylene glycol (PEG) 4000 implanted group; (4) Ti + PEG 4000 + L-NAME (2 × 10−4 M) implanted group and (5) i.p. L-NAME administrated group (10 mg/kg). At 5 days after oral incision operations, wound tissue
strips and plasma were obtained from rabbits. Oral wound tissue and plasma nitric oxide, plasma thiobarbituric acid reactive
substances (TBARS) and total sulfhydryl group (RSH) levels were investigated. Plasma TBARS and NOx levels decreased after
i.p. L-NAME administration. Total RSH group levels were not changed in all groups (p>0.05). This means that L-NAME inhibits the deteriorating effects of free radicals without affecting healing. L-NAME in PEG
and titanium also has no effect on tissue and plasma NOx levels. These findings indicate that NO generation will not be affected
both Ti and local nitric oxide synthase (NOS) inhibitor. (Mol Cell Biochem 278: 65–69, 2005) 相似文献
89.
90.
Yelda Güzel Ekrem Aktoklu Vincent Roumy Racha Alkhatib Thierry Hennebelle François Bailleul Sevser Şahpaz 《Biochemical Systematics and Ecology》2011,39(4-6):781-786
The flavonoid profiles of Turkish Torilis Gaertn. (Apiaceae) species were studied by TLC, HPLC-UV and HPLC/ESI/MS2 (negative mode). O-glycosides of luteolin, apigenin and chrysoeriol were identified from crude extracts with the help of mass spectra in different MS/MS modes, such as full scan, precursor ion scan and product ion scan. Luteolin-7-O-glucoside and luteolin-7-O-rutinoside were common to all species. Flavonoid profiles usually differ from one species to another and can be put to use for a genus such as Torilis which has been little studied. By the help of different flavonoid profiles, it is concluded that, the plants, which are recognised as less rayed subspecies of Torilis arvensis (Huds.) Link. in various floras including Turkish one, must be classified in species category as Torilis chrysocarpa and Torilis purpurea. Flavonoid profiles seem to be in relation with evolutionary biogeography of the species. Because the most isolated species of the genus, endemic Torilis triradiata, has the most different flavonoid pattern. Moreover, geographically isolated species, T. triradiata and Torilis leptocarpa, do not share any flavonoid except for the two which are common to all species. 相似文献