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361.
We aimed to evaluate changes in antioxidant status in blood during valproate (VPA) monotherapy of adult patients with epilepsy. Antioxidant enzymes [plasma superoxide dismutase (pSOD), erythrocyte superoxide dismutase (eSOD)] and non-enzymatic indices [concentration of trace elements in serum: selenium, copper, zinc (sZn) and uric acid (UA), as well as the ferric reducing ability of plasma (FRAP) and UA-independent FRAP (UAiFRAP)] were evaluated in 21 adult patients with epilepsy and 21 healthy controls. Significant differences between the study group and controls were found for pSOD (p = 0.002) and UAiFRAP (p = 0.003). pSOD was higher, whilst UAiFRAP was lower in patients compared to controls. The activity of eSOD was higher in patients treated with VPA for a longer period (7–14 years) in comparison to controls (p = 0.001) and patients with a short period of VPA treatment (p < 0.001). Patients with uncontrolled epilepsy exhibited higher sZn than seizure-free patients (p = 0.041). Standard diet and moderate use of alcohol and/or nicotine did not exert significant effects on redox balance. We conclude that the antioxidant status of epileptic patients is modified by valproate monotherapy. The frequency of seizures and duration of VPA therapy are associated with changes of oxidative/antioxidative balance. The most sensitive and relevant parameters for antioxidative defence mechanism are pSOD, UAiFRAP and sZn.  相似文献   
362.
Three dimensional scaffolds are becoming increasingly popular in the treatment of cartilage defects. Platelet-rich plasma (PRP) and fibrinogen can be used potentially as a three dimensional cell delivery vehicle. PRP is a fraction of plasma containing high levels of growth factors such as PDGF, IGF-I and TGF-I, which stimulate chondrocyte to synthesize extracellular matrix. The aim of this study was to prepare grafts based on fibrinogen, and PRP with fibrinogen as a chondrocyte carrier. Another goal was to estimate tranexamic acid as an antifibrynolytic agent in chondrocyte grafts and in monolayer culture for about 3 weeks. 450 ml blood was collected to produce fibrinogen and PRP from a Regional Blood Center voluntary donor. To prepare gel grafts, chondrocytes were mixed with PRP and, fibrinogen and then with thrombin in calcium chloride. Different doses of tranexamic acid or aprotinin were used to stabilize the constructs. Grafts were cultivated for 4 weeks in vitro to evaluate and compare their disintegration. Grafts were stable for the entire observation period and revealed no shrinkage. During graft storage, cells appeared to be viable, and cell migration from the graft to the culture plate was observed. Chondrocyte graft preparation based on PRP and fibrinogen is a promising method. PRP-fibrinogen carrier in combination with cells constitutes highly plastic and adhesive grafts. Tranexamic acid can be used as an anti-fibrinolytic agent in chondrocyte graft preparation instead of aprotinin.  相似文献   
363.
364.
The aim of the study was to evaluate the effect of essential oils obtained from Thymus vulgaris L., Origanum vulgare L., Origanum majerana L., Mentha × piperita L. and Allium ursinum L. against Prototheca zopfii strains that cause inflammation of the udder (mastitis) in cows. The study was conducted on ten strains derived from milk samples. The microdilution method was used to determine the sensitivity of P. zopfii strains to the studied essential oils, and the disk diffusion method was used to determine the sensitivity to antifungal chemotherapeutics. The plates were incubated for 48 h at 37 °C under aerobic conditions. All strains of algae were sensitive to the essential oils marjoram, thyme and oregano and resistant to mint and garlic oils. MIC values ranged from 0.25 to 1 μl/ml. Marjoram oil demonstrated the greatest activity, and oregano oil the weakest. Among the antifungal agents tested, 90% of strains showed sensitivity to nystatin. One of the tested strains (71/IV) was resistant to all investigated antifungal agents. The tested essential oils are known to have anti-algae activity and can be used as natural agents for prophylaxis in animals, particularly in mastitis-affected cows.  相似文献   
365.
Although a number of studies have focused on the higher ethyl pyruvate antioxidative activity than its sodium salt under various stress conditions, and the greater protective properties of the ester form have been suggested as the effect of better cell membrane penetration, the molecular mechanism has remained unclear. The aim of the present study was therefore to compare the antioxidative activities of sodium and ethyl pyruvate under in vitro conditions by using a liver homogenate as the model for cell membrane transport deletion. The potential effect of ethanol was also evaluated, and hypochlorous acid was used as an oxidant. Our data indicate the concentration-dependent scavenging potency of both sodium and ethyl pyruvate, with the ester having higher activity. This effect was not related to the presence of ethanol. Better protection of the liver homogenate by ethyl pyruvate was also apparent, despite the fact that cell membrane transport was omitted.  相似文献   
366.
"Photobacterium mandapamensis" (proposed name) and Photobacterium leiognathi are closely related, phenotypically similar marine bacteria that form bioluminescent symbioses with marine animals. Despite their similarity, however, these bacteria can be distinguished phylogenetically by sequence divergence of their luminescence genes, luxCDAB(F)E, by the presence (P. mandapamensis) or the absence (P. leiognathi) of luxF and, as shown here, by the sequence divergence of genes involved in the synthesis of riboflavin, ribBHA. To gain insight into the possibility that P. mandapamensis and P. leiognathi are ecologically distinct, we used these phylogenetic criteria to determine the incidence of P. mandapamensis as a bioluminescent symbiont of marine animals. Five fish species, Acropoma japonicum (Perciformes, Acropomatidae), Photopectoralis panayensis and Photopectoralis bindus (Perciformes, Leiognathidae), Siphamia versicolor (Perciformes, Apogonidae), and Gadella jordani (Gadiformes, Moridae), were found to harbor P. mandapamensis in their light organs. Specimens of A. japonicus, P. panayensis, and P. bindus harbored P. mandapamensis and P. leiognathi together as cosymbionts of the same light organ. Regardless of cosymbiosis, P. mandapamensis was the predominant symbiont of A. japonicum, and it was the apparently exclusive symbiont of S. versicolor and G. jordani. In contrast, P. leiognathi was found to be the predominant symbiont of P. panayensis and P. bindus, and it appears to be the exclusive symbiont of other leiognathid fishes and a loliginid squid. A phylogenetic test for cospeciation revealed no evidence of codivergence between P. mandapamensis and its host fishes, indicating that coevolution apparently is not the basis for this bacterium's host preferences. These results, which are the first report of bacterial cosymbiosis in fish light organs and the first demonstration that P. leiognathi is not the exclusive light organ symbiont of leiognathid fishes, demonstrate that the host species ranges of P. mandapamensis and P. leiognathi are substantially distinct. The host range difference underscores possible differences in the environmental distributions and physiologies of these two bacterial species.  相似文献   
367.
Breeding of apple (Malus × domestica) remains a slow process because of protracted generation cycles. Shortening the juvenile phase to achieve the introgression of traits from wild species into prebreeding material within a reasonable time frame is a great challenge. In this study, we evaluated early flowering transgenic apple lines overexpressing the BpMADS4 gene of silver birch with regard to tree morphology in glasshouse conditions. Based on the results obtained, line T1190 was selected for further analysis and application to fast breeding. The DNA sequences flanking the T-DNA were isolated and the T-DNA integration site was mapped on linkage group 4. The inheritance and correctness of the T-DNA integration were confirmed after meiosis. A crossbred breeding programme was initiated by crossing T1190 with the fire blight-resistant wild species Malus fusca. Transgenic early flowering F(1) seedlings were selected and backcrossed with 'Regia' and 98/6-10 in order to introgress the apple scab Rvi2, Rvi4 and powdery mildew Pl-1, Pl-2 resistance genes and the fire blight resistance quantitative trait locus FB-F7 present in 'Regia'. Three transgenic BC'1 seedlings pyramiding Rvi2, Rvi4 and FB-F7, as well as three other BC'1 seedlings combining Pl-1 and Pl-2, were identified. Thus, the first transgenic early flowering-based apple breeding programme combined with marker-assisted selection was established.  相似文献   
368.
Positron emission tomography with [18F] fluorodeoxyglucose (FDG-PET) plays a well-established role in assisting early detection of frontotemporal lobar degeneration (FTLD). Here, we examined the impact of intensity normalization to different reference areas on accuracy of FDG-PET to discriminate between patients with mild FTLD and healthy elderly subjects. FDG-PET was conducted at two centers using different acquisition protocols: 41 FTLD patients and 42 controls were studied at center 1, 11 FTLD patients and 13 controls were studied at center 2. All PET images were intensity normalized to the cerebellum, primary sensorimotor cortex (SMC), cerebral global mean (CGM), and a reference cluster with most preserved FDG uptake in the aforementioned patients group of center 1. Metabolic deficits in the patient group at center 1 appeared 1.5, 3.6, and 4.6 times greater in spatial extent, when tracer uptake was normalized to the reference cluster rather than to the cerebellum, SMC, and CGM, respectively. Logistic regression analyses based on normalized values from FTLD-typical regions showed that at center 1, cerebellar, SMC, CGM, and cluster normalizations differentiated patients from controls with accuracies of 86%, 76%, 75% and 90%, respectively. A similar order of effects was found at center 2. Cluster normalization leads to a significant increase of statistical power in detecting early FTLD-associated metabolic deficits. The established FTLD-specific cluster can be used to improve detection of FTLD on a single case basis at independent centers – a decisive step towards early diagnosis and prediction of FTLD syndromes enabling specific therapies in the future.  相似文献   
369.
Powdery mildew, caused by Blumeria graminis is an important disease of cereals in many production regions. Until end of the last century triticale had been regarded as a species characterized by high level of resistance for this disease. However, after several years of intensive production on a big area in Poland, Germany and other European countries it start to be susceptible for many pathogens including B. graminis. Because of this, virulence structure of this pathogen population on triticale in Poland was evaluated across 2008–2010. Leaf samples with symptoms of the powdery mildew disease were collected randomly from nineteen localities. As a total, 1402 B. graminis isolates were collected: 23–25 isolates per locality in each year. Standard differential set of 28 genotypes was used: twenty‐one wheat with known resistance genes and seven triticale. Based on the obtained results it was possible to observe significant differences in virulence structure between years and localities. No virulence's against Pm21 (Yangmai5), and Pm3d + 4b (Kadett) were found in any year. All tested isolates were virulent on Moreno and Lamberto cultivars. In a total, 36% of tested isolates possessed 9, 11 or 12 virulence's per genotypes. Twenty five percent of tested isolates were virulent to 5 triticale cultivars. Correlation between pathotypes frequency and sampling region were not found what suggest that local epidemics play the most important role in triticale growing regions in Poland.  相似文献   
370.
A series of new 3-methylidenechroman-2-ones bearing various aromatic moieties and various substituents at position 4 were synthesized in a three step reaction sequence. Friedel-Crafts alkylation of phenols or naphthols using ethyl 3-methoxy-2-diethoxyphosphorylacrylate in the presence of trifluoromethanesulphonic acid gave 3-diethoxyphosphorylchromen-2-ones. These compounds were employed as Michael acceptors in the reaction with Grignard reagents to give adducts which were finally used as Horner-Wadsworth-Emmons reagents for the olefination of formaldehyde. All obtained 3-methylidenechroman-2-ones were tested against two human leukemia cell lines NALM-6 and HL-60 as well as MCF-7 breast cancer and HT-29 colon cancer adenocarcinomas. Several obtained methylidenechromanones displayed high cytotoxic activity with IC(50) values below 1μM, mainly against leukemia and MCF-7 cell lines. Investigation of structure-activity relationships revealed that the presence of additional, ortho-fused benzene ring and n-butyl or i-propyl group in position 4 enhances the activity. Selected methylidenechromanones were also tested on normal human umbilical vein endothelial cells (HUVEC) and chromanone 14o was found to be eightfold more toxic against MCF-7 than normal cells. Furthermore, antimicrobial assays revealed that chromanone 14n is highly active and bactericidal at concentration equal to MIC or 2MIC against nosocomial and community-associated staphylococci (MRSA) which are resistant to most or all available therapeutic classes of antimicrobial drugs.  相似文献   
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