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11.
I M Szabó M Marton G Kulcsár I Buti 《Acta microbiologica Academiae Scientiarum Hungaricae》1976,23(4):371-376
Strain FBUA 1274 (=strain 28/650707, Hungarian National Collection of Medical Bacteria, National Institute of Public Health, Budapest) is designated the type strain of Thermonospora galeriensis (Vályi-Nagy et al.) comb. nov., and the morphological characteristics of this strain are described. 相似文献
12.
Chronic coccidian infestation compromises flight feather quality in house sparrows Passer domesticus
Péter L. Pap Csongor I. Vágási Lőrinc Bărbos Attila Marton 《Biological journal of the Linnean Society. Linnean Society of London》2013,108(2):414-428
Parasites usurp indispensable resources for birds during a moult, and this is particularly relevant for those parasites residing in host intestines. This might compromise the nutritionally demanding moult and, thus, feather functionality. Although lower feather quality has profound and multifaceted adverse effects on residual fitness, surprisingly, little is known about parasites' effect on feather traits, especially over the longer term. We conducted an aviary experiment by medicating half of a group of naturally infested house sparrows Passer domesticus against intestinal coccidians for 15 months, spanning two consecutive postnuptial moults, whereas the other half was kept infested (i.e. without medication). Coccidian infestation significantly and negatively affected the size of the uropygial gland during the second moulting period compared to the medicated group. Furthermore, wing length was significantly shorter after the second moulting in the non‐medicated compared to the medicated female birds, which indicates that the negative effects of coccidians emerge only after a prolonged exposure to parasite infestation. Non‐medicated birds grew poorer quality flight feathers detected in a large number of feather traits both after the first and second moults. In the case of non‐medicated birds, the primaries were lighter and shorter, and had a smaller vane area, thinner rachis and decreased stiffness, although a higher barb and barbule density, which may have various consequences for fitness through reducing flight performance. Our findings demonstrate that, besides the well‐known immediate consequences for host breeding success, parasites might also have serious, long‐lasting effects through influencing feather quality and, ultimately, fitness of the host. © 2013 The Linnean Society of London 相似文献
13.
Immobilized metal affinity chromatography optimized for the analysis of extracellular phosphorylation 下载免费PDF全文
Phosphorylation is the most widely studied posttranslational modification. Its role within the cell has been the focus of numerous large‐scale studies. Recently there is growing evidence on the biological significance of extracellular phosphorylation. The analysis of these phosphopeptides is complicated by the abundance of glycosylation in the extracellular space, since glycopeptides are also enriched by the methods used for phosphopeptide isolation. Thus, we optimized IMAC for phosphorylation analysis of secreted proteins, specifically in human serum. Selectivity and efficiency of different enrichment conditions used in earlier large‐scale phosphoproteomic studies were evaluated. We found that minimizing hydrophilic interactions in the enrichment allowed selective phosphopeptide isolation. Using a two‐step IMAC enrichment protocol under these conditions led to the identification of ~100 phosphorylation sites from the tryptic digest of as little as 40 μL human serum. 相似文献
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15.
C. I. Vágási O. Vincze L. Pătraş G. Osváth A. Marton L. Bărbos D. Sol P. L. Pap 《Journal of evolutionary biology》2016,29(10):1968-1976
Large brains (relative to body size) might confer fitness benefits to animals. Although the putative costs of well‐developed brains can constrain the majority of species to modest brain sizes, these costs are still poorly understood. Given that the neural tissue is energetically expensive and demands antioxidants, one potential cost of developing and maintaining large brains is increased oxidative stress (‘oxidation exposure’ hypothesis). Alternatively, because large‐brained species exhibit slow‐paced life histories, they are expected to invest more into self‐maintenance such as an efficacious antioxidative defence machinery (‘oxidation avoidance’ hypothesis). We predict decreased antioxidant levels and/or increased oxidative damage in large‐brained species in case of oxidation exposure, and the contrary in case of oxidation avoidance. We address these contrasting hypotheses for the first time by means of a phylogenetic comparative approach based on an unprecedented data set of four redox state markers from 85 European bird species. Large‐brained birds suffered less oxidative damage to lipids (measured as malondialdehyde levels) and exhibited higher total nonenzymatic antioxidant capacity than small‐brained birds, whereas uric acid and glutathione levels were independent of brain size. These results were not altered by potentially confounding variables and did not depend on how relative brain size was quantified. Our findings partially support the ‘oxidation avoidance’ hypothesis and provide a physiological explanation for the linkage of large brains with slow‐paced life histories: reduced oxidative stress of large‐brained birds can secure brain functionality and healthy life span, which are integral to their lifetime fitness and slow‐paced life history. 相似文献
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17.
Pacher P Mabley JG Liaudet L Evgenov OV Marton A Haskó G Kollai M Szabó C 《American journal of physiology. Heart and circulatory physiology》2004,287(5):H2132-H2137
Aging is associated with profound changes in the structure and function of the heart. A fundamental understanding of these processes, using relevant animal models, is required for effective prevention and treatment of cardiovascular disease in the elderly. Here, we studied cardiac performance in 4- to 5-mo-old (young) and 24- to 26-mo-old (old) Fischer 344 male rats using the Millar pressure-volume (P-V) conductance catheter system. We evaluated systolic and diastolic function in vivo at different preloads, including preload recruitable stroke work (PRSW), maximal slope of the systolic pressure increment (+dP/dt), and its relation to end-diastolic volume (+dP/dt-EDV) as well as the time constant of left ventricular pressure decay, as an index of relaxation. The slope of the end-diastolic P-V relation (EDPVR), an index of left ventricular stiffness, was also calculated. Aging was associated with decrease in left ventricular systolic pressure, +dP/dt, maximal slope of the diastolic pressure decrement, +dP/dt-EDV, PRSW, ejection fraction, stroke volume, cardiac and stroke work indexes, and efficiency. In contrast, total peripheral resistance, left ventricular end-diastolic volume, left ventricular end-diastolic pressure, and EDPVR were greater in aging than in young animals. Taken together, these data suggest that advanced aging is characterized by decreased systolic performance accompanied by delayed relaxation and increased diastolic stiffness of the heart in male Fischer 344 rats. P-V analysis is a sensitive method to determine cardiac function in rats. 相似文献
18.
In our Department we have studied the first line treatment of 90 stage IIIA-IV non-small cell lung cancer patients using gemcitabine/cisplatin combination. Thirteen cases have been unevaluable for various reasons. At the time of evaluation the planned 4 cycles have been delivered to 38% of patients (34/90). The PR was 39% (30/77), the CR was 2.6% (2/77) while the ORR was found to be 41% (32/77). 226 treatment cycles have been evaluated for side effects. There was no treatment-induced death in this series. CTC grade 3-4 neutropenia occurred in 5.7% of the cycles and only in 2 cases combined with fever. CTC grade 3-4 thrombocytopenia occurred in 4.4% of the cycles but only one patient required platelet suspension administration. Grade 3-4 anaemia developed in 3.5% of the cycles where 5 cases have been treated with RBC concentrate while 3 cases with erythropoietin. Complete alopecia occurred in 6 patients but 3 of them received brain irradiation as well. CTC grade 3-4 nausea and vomiting occurred in 4.4 and 3% of the cycles, respectively, but rehydration was only necessary in 3% of the cycles. Delay of the therapy due to hematological toxicity or vomiting occurred in 8% of the cycles but did not last longer than 2 weeks. Severe CTC grade 3-4 nephrotoxicity did not occur in this study while grade 1-2 elevation of serum creatinine level was found in 1.7% of the cycles. We have concluded that the gemcitabine/cisplatin combination is a safe outpatient modality for the first line treatment of advanced non-small cell lung cancer patients. 相似文献
19.
Diabetic endothelial dysfunction: the role of poly(ADP-ribose) polymerase activation 总被引:27,自引:0,他引:27
Garcia Soriano F Virág L Jagtap P Szabó E Mabley JG Liaudet L Marton A Hoyt DG Murthy KG Salzman AL Southan GJ Szabó C 《Nature medicine》2001,7(1):108-113
Diabetic patients frequently suffer from retinopathy, nephropathy, neuropathy and accelerated atherosclerosis. The loss of endothelial function precedes these vascular alterations. Here we report that activation of poly(ADP-ribose) polymerase (PARP) is an important factor in the pathogenesis of endothelial dysfunction in diabetes. Destruction of islet cells with streptozotocin in mice induced hyperglycemia, intravascular oxidant production, DNA strand breakage, PARP activation and a selective loss of endothelium-dependent vasodilation. Treatment with a novel potent PARP inhibitor, starting after the time of islet destruction, maintained normal vascular responsiveness, despite the persistence of severe hyperglycemia. Endothelial cells incubated in high glucose exhibited production of reactive nitrogen and oxygen species, consequent single-strand DNA breakage, PARP activation and associated metabolic and functional impairment. Basal and high-glucose-induced nuclear factor-kappaB activation were suppressed in the PARP-deficient cells. Our results indicate that PARP may be a novel drug target for the therapy of diabetic endothelial dysfunction. 相似文献
20.
Plexins are neuronal receptors for the repulsive axon guidance molecule Semaphorins. Previous studies showed that Plexin B (PlexB) binds directly to the active, GTP-bound form of the Rac GTPase. Here, we define a seven amino acid sequence in PlexB required for Rac(GTP) binding. The interaction of PlexB with Rac(GTP) is necessary for Plexin-mediated axon guidance in vivo. A different region of PlexB binds to RhoA. Dosage-sensitive genetic interactions suggest that PlexB suppresses Rac activity and enhances RhoA activity. Biochemical evidence indicates that PlexB sequesters Rac(GTP) from its downstream effector PAK. These results suggest a model whereby PlexB mediates repulsion by coordinately regulating two small GTPases in opposite directions: PlexB binds to Rac(GTP) and downregulates its output by blocking its access to PAK and, at the same time, binds to and increases the output of RhoA. 相似文献