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81.
A collection of 96 female Turkish fig (Ficus carica L.) accessions was studied to elucidate genetic structure and estimate diversity and genetic similarity distribution among
the female figs present in Turkish genetic resources, using 157 molecular genome markers including 129 sequence-related amplified
polymorphisms, 21 random amplified polymorphic DNAs, and 7 simple-sequence repeats. The plant samples mainly included Turkish
fig collections selected throughout the country over the course of a half-century. Neighbor-joining analysis revealed continuous
dissimilarity range, and it was difficult to classify figs into distinct groups. The principle component analysis produced
similar results. The analysis of molecular variance indicated that 95 and 93% of genetic variation were explained by within
geographic origins and similar fruit rind color, respectively. Sub-structuring Bayesian analysis assigned the 96 female figs
into four sub-populations, and indicated that they were highly related. The corrected allelic pairwise distances among the
six geographic origins were less than 5%. This study suggests that geography- and color-based groups were not genetically
distinct among the Turkish figs. 相似文献
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Athar Ata Chad D. Iverson Kosmulalage S. Kalhari Sarfraz Akhter Jordan Betteridge Mohammad Hadi Meshkatalsadat Ilkay Orhan Bilge Sener 《Phytochemistry》2010,71(14-15):1780-1786
From the aerial parts of Buxus hyrcana, three triterpenoidal alkaloids, 17-oxo-3-benzoylbuxadine (1), buxhyrcamine (2), and 31-demethylcyclobuxoviridine (3), along with 16 known compounds, cyclobuxoviridine (4), Nb-dimethylcyclobuxoviricine (5), E-buxenone (6), Z-buxenone (7), moenjodaramine (8), homomoenjodarmine (9), buxamine A (10), buxamine B (11), 31-hydroxybuxamine B (12), N20-formylbuxaminol E (13), papillozine C (14), buxmicrophylline F (15), buxrugulosamine (16), cyclobuxophylline O (17), spirofornabuxine (18) and arbora-1,9(11)-dien-3-one (19) were isolated. Their structures were elucidated by using NMR spectroscopic methods. All of the compounds exhibited moderate to weak acetylcholinesterase, butyrylcholinesterase and glutathione S-transferase inhibitory activities. Compounds 1–19 also exhibited modest anti-fungal activities against Candida albicans. Compounds 1, 2, 8, 9 and 18 also exhibited weak anti-leishmanial activity. 相似文献
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Genome-wide mapping of DNA synthesis in Saccharomyces cerevisiae reveals that mechanisms preventing reinitiation of DNA replication are not redundant
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To maintain genomic stability, reinitiation of eukaryotic DNA replication within a single cell cycle is blocked by multiple mechanisms that inactivate or remove replication proteins after G1 phase. Consistent with the prevailing notion that these mechanisms are redundant, we previously showed that simultaneous deregulation of three replication proteins, ORC, Cdc6, and Mcm2-7, was necessary to cause detectable bulk re-replication in G2/M phase in Saccharomyces cerevisiae. In this study, we used microarray comparative genomic hybridization (CGH) to provide a more comprehensive and detailed analysis of re-replication. This genome-wide analysis suggests that reinitiation in G2/M phase primarily occurs at a subset of both active and latent origins, but is independent of chromosomal determinants that specify the use and timing of these origins in S phase. We demonstrate that re-replication can be induced within S phase, but differs in amount and location from re-replication in G2/M phase, illustrating the dynamic nature of DNA replication controls. Finally, we show that very limited re-replication can be detected by microarray CGH when only two replication proteins are deregulated, suggesting that the mechanisms blocking re-replication are not redundant. Therefore we propose that eukaryotic re-replication at levels below current detection limits may be more prevalent and a greater source of genomic instability than previously appreciated. 相似文献
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Elif Ayazoglu Demir Ahmet Mentese Hatice Kucuk Nihal Turkmen Alemdar Selim Demir 《Journal of biochemical and molecular toxicology》2023,37(9):e23408
5-Fluorouracil (5-FU) is a fluoropyrimidine group antineoplastic drug with antimetabolite properties and ovotoxicity is one of the most important side effects. Silibinin (SLB) is a natural compound that is used worldwide and stands out with its antioxidant and anti-inflammatory properties. The aim of this study was to evaluate the therapeutic effect of SLB in 5-FU-induced ovototoxicity using biochemical and histological analysis. This study was carried out in five main groups containing six rats in each group: control, SLB (5 mg/kg), 5-FU (100 mg/kg), 5-FU + SLB (2.5 mg/kg), and 5-FU + SLB (5 mg/kg). The levels of ovarian malondialdehyde (MDA), total oxidant status (TOS), total antioxidant status (TAS), superoxide dismutase (SOD), catalase (CAT), 8-hydroxy-2′-deoxyguanosine (8-OHdG), tumor necrosis factor-alpha (TNF-α), myeloperoxidase (MPO), and caspase-3 were determined using spectrophotometric methods. Hematoxylin and eosin staining method was employed for histopathological examination. MDA, TOS, 8-OHdG, TNF-α, MPO, and caspase-3 levels in 5-FU group were significantly increased compared with the control group, while the levels of TAS, SOD, and CAT were decreased (p < 0.05). SLB treatments statistically significantly restored this damage in a dose-dependent manner (p < 0.05). Although vascular congestion, edema, hemorrhage, follicular degeneration, and leukocyte infiltration were significantly higher in the 5-FU group compared with the control group, SLB treatments also statistically significantly restored these damages (p < 0.05). In conclusion, SLB has a therapeutic effect on the ovarian damage induced by 5-FU via decreasing the levels of oxidative stress, inflammation, and apoptosis. It may be helpful to consider the usefulness of SLB as an adjuvant therapy to counteract the side effects of chemotherapy. 相似文献
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Umbelopsis ramanniana was investigated to increase carotenoid production. Nine different carbon sources and six different nitrogen sources were evaluated for the maximum carotenoid production. The most effective nitrogen and carbon sources were KNO3 and lactose, respectively. Then, the optimization of medium components for enhancement of carotenoid production by Umbelopsis ramanniana was achieved using Plackett–Burman design. Box–Behnken response surface methodology was applied to further optimize carotenoid and biomass production. Carbon to nitrogen ratio, lactose concentration, and shaking speed were studied as variables in Box–Behnken design. The optimum conditions for carotenoid and biomass production were determined as 32.42 g/L of lactose concentration, 20:1 of carbon to nitrogen ratio, and shaking speed of 130 rpm. The maximum carotenoid and biomass production under optimized conditions were 1141 μg/L (β-carotene-Eq) and 13.14 g/L, respectively. When compared to the control fermentation, carotenoid, and biomass production were increased by about 2 and 1.3 folds, respectively. 相似文献
88.
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
89.
Ozer C Gönül B Elmas C Erdoüan D Ercan ZS 《Molecular and cellular biochemistry》2005,280(1-2):151-157
Dexfenfluramine is one of the anorectic drugs that suppresses food intake which acts via inhibition of reuptake of serotonin
into brain terminal. Gastrointestinal tract is the main source of peripheral serotonin which is involved in the regulation
of gastrointestinal motility. During the use of anorectic drugs, the antioxidant defence is affected especially by reactive
oxygen species.
The purpose of this study to search: The effect of dexfenfluramine on serotonin levels of ileum and the effect of dexfenfluramine
on ileal contractility and oxidative stress.
Materials and Methods: Twenty-two adult male Swiss-albino mice were divided two groups (1) Control, (2) Dexfenfluramine treated
(i.p. twice a day 0.2 mg kg−1 in 0.2 ml saline solution for 7 days). Animal body weights were recorded at the beginning and at the end of the experimental
period. Ileum tissues contractile responses to different concentrations of KCl and acethycholine were recorded on polygraph.
In the meantime ileal tissue malondialdehyde, a product of lipid peroxidation, and glutathione, endogenous antioxidant levels
were assessed by spectrophotometric methods. Ileal tissue serotonin level determined by immunohistochemical method. Body weights
decrease and ileal contractile response of acethycholine increased significantly by dexfenfluramine treatment. Meanwhile,
ileum glutathione levels decreased and malondialdehyde levels increased in dexfenfluramine treated group. Immunohistochemical
detection showed that ileal serotonin levels increased by dexfenfluramine treatments.
As a conclusion, there is a relationship between increased ileal contractility and oxidant status in dexfenfluramine treated
animals. These effects can be related by increased serotonin levels which is induced by dexfenfluramine in ileum. (Mol Cell
Biochem xxx: 151–157, 2005) 相似文献
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