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31.
DNase I inhibitory potential of water extract of nine Hypericum species (H. umbellatum, H. barbatum, H. rumeliacum, H. rochelii, H. perforatum, H. tetrapterum, H. olympicum, H. hirsutum, H. linarioides) and the most important Hypericum secondary metabolites (hypericin, hyperforin, quercetin, and rutin) was investigated. All examined Hypericum extracts inhibited DNase I with IC50 below 800 μg/ml, whereby H. perforatum was the most potent (IC50=391.26±68.40 μg/ml). Among the investigated Hypericum secondary metabolites, rutin inhibited bovine pancreatic DNase I in a non‐competitive manner with IC50 value of 108.90±9.73 μm . DNase I inhibitory ability of rutin was further confirmed on DNase I in rat liver homogenate (IC50=137.17±16.65 μm ). Due to the involvement of DNase I in apoptotic processes the results of this study indicate the importance of frequent rutin and H. perforatum consumption in daily human nutrition. Rutin is a dietary component that can contribute to male infertility prevention by showing dual mechanism of sperm DNA protection, DNase I inhibition and antioxidant activity.  相似文献   
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PURPOSETo determine whether volumetric changes of enhancement as seen on contrast-enhanced magnetic resonance (MR) imaging can help assess early tumor response and predict survival in patients with metastatic uveal melanoma after one session of transarterial chemoembolization (TACE).MATERIALS AND METHODSFifteen patients with 59 lesions who underwent MR imaging before and 3 to 4 weeks after the first TACE were retrospectively included. MR analysis evaluated signal intensities, World Health Organization (WHO), Response Evaluation Criteria in Solid Tumors (RECIST), European Association for the Study of the Liver (EASL), modified RECIST (mRECIST), tumor volume [volumetric RECIST (vRECIST)], and volumetric tumor enhancement [quantitative EASL (qEASL)]. qEASL was expressed in cubic centimeters [qEASL (cm3)] and as a percentage of the tumor volume [qEASL (%)]. Paired t test with its exact permutation distribution was used to compare measurements before and after TACE. The Kaplan-Meier method with the log-rank test was used to calculate overall survival for responders and non-responders.RESULTSIn target lesions, mean qEASL (%) decreased from 63.9% to 42.6% (P = .016). No significant changes were observed using the other response criteria. In non-target lesions, mean WHO, RECIST, EASL, mRECIST, vRECIST, and qEASL (cm3) were significantly increased compared to baseline. qEASL (%) remained stable (P = .214). Median overall survival was 5.6 months. qEASL (cm3) was the only parameter that could predict survival based on target lesions (3.6 vs 40.5 months, P < .001) or overall (target and non-target lesions) response (4.4 vs 40.9 months, P = .001).CONCLUSIONVolumetric tumor enhancement may be used as a surrogate biomarker for survival prediction in patients with uveal melanoma after the first TACE.  相似文献   
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We analyzed the developmental time, egg-to-adult viability, and developmental stability (fluctuating wing size asymmetry) in Drosophila subobscura, maintained for six generations on different concentrations of lead. Development time is significantly affected by generation and lead concentration, but interaction of these factors is not a significant source of variability for this fitness component. Generation and the interaction generation x concentration of lead significantly affect egg-to-adult viability. Levene's test of heterogeneity of variance showed that variability of FA is not significant in any of the samples. Within both lead concentrations females showed significantly higher FA indices for the wing width than males. Within sexes, a significantly higher FA was found only in females for wing width FA between the control and the lower concentration of lead. The results show that if strong relationship between FA and the studied fitness components exists, it results in a stronger selection of unstable genotypes under lead as a stress factor and, consequently, FA needs to be used with caution as a biomarker in natural populations under environmental stress.  相似文献   
34.
The Amy locus polymorphism of Drosophila subobscura is used as a model system for an experimental population genetic study of adaptive significance of α-amylase activity on substrates of different carbohydrate compositions. So far, fitness components have not commonly been included in ecological-genetic studies of α-amylase polymorphism in this species. In the present paper, fitness components are analyzed in relation to different amylase activities in D. subobscura individuals homozygous for the “slow” and the “fast” Amy allele, associated with substrates of different carbohydrate compositions. The results indicate a significant effect of substrate carbohydrate composition on fitness components of the genotypes homozygous for S or F Amy allele in D. subobscura through their enzyme activity. The text was submitted by the authors in English.  相似文献   
35.
Changes in the number and ex vivo function of peripheral blood neutrophils were investigated following intraperitoneal administration of cadmium-chloride in rats. Besides a dose-dependent increase in the number of peripheral blood neutrophils, changes were found in the functional state of isolated polymorphonuclear leukocytes (PMNs). Increased spontaneous adhesion and activation, and TNF activity in a conditioned medium were observed in cultures of granulocytes in comparison to granulocytes from control (saline-treated) animals. Increased levels of plasma activity of inflammatory cytokines, tumor necrosis factor (TNF) and interleukin-6 (IL-6) were noted following cadmium administration. Cytological signs of pulmonary inflammation were revealed histologically and the majority of neutrophils recovered from the lungs by enzyme digestion exhibited a capacity of nitroblue tetrazolium (NBT) reduction. Our data demonstrate that acute cadmium intoxication leads to a systemic inflammatory response characterized by numerical and functional changes in the granulocyte compartment and to increased levels of inflammation-related cytokine activity in the circulation. Correlations between the increased number of peripheral blood neutrophils and IL-6 plasma activity (r=0.776, p<0.00001) and the number of neutrophils recovered from the lung tissue (r=0.893, p<0.00001) suggested that systemic cadmium-induced inflammation might be involved in the pulmonary toxicity of cadmium.  相似文献   
36.
Summary Mutations in the cysB and cysE genes of Escherichia coli K12 cause an increase in resistance to the gyrase inhibitor novobiocin but not to coumermycin, acriflavine and rifampicin. This unusual relationship was also observed among spontaneous novobiocin resistant (Novr) mutants: 10% of Novr mutants isolated on rich (LA) plates with novobiocin could not grow on minimal plates, and among those approximately half were cysB or cysE mutants. Further analyses demonstrated that cysB and cysE negative alleles neither interfere with transport of novobiocin nor affect DNA supercoiling.  相似文献   
37.
The biosynthesis of placental proteins and placental lactogen (HPL) was studied in vitro in 10–12 week, 16–18 week and term human placenta in the presence and absence of PGE. The highest 14C-leucine incorporation was detected in 10 to 12 weeks old placentas. Addition of PGE to the induction medium depressed the rate of incorporation of 14C-leucine into placental proteins on a dose dependent manner. Placentas most sensitive to this action of PGE were those obtained at 18 weeks gestation followed by placentas at term. In vivo application of PGE for tharapeutic induction of abortions resulted in the marked inhibition of placental protein synthesis in vitro.  相似文献   
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