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81.
We estimated neutral diversity of 21 European cattle breeds with 105 microsatellites. Nine of them resembled unselected Balkan Buša strains with diffuse breeding barriers and the 12 others were strongly differentiated, isolated breeds. Because of the impact of neutral genetic diversity on long-term population adaptive capacity, we discuss the long-term outcome of different conservation priorities in a subdivided metapopulation of the investigated cattle breeds. The optimal contribution to a pool of total genetic diversity allocated more than 95% of long-term relevant neutral diversity to virtually unselected strains of the Balkan Buša, while the maximization of total variance preferred inbred breeds. Current artificial selection methods, such as genomic selection sped up and a recovery of underestimated traits becomes quickly impossible. We emphasize that currently neutral and even deleterious alleles might be required for future genotypes in sustainable and efficient livestock breeding and production systems of a 21st century. We provide cumulative evidences that long-term survival relies on genetic complexity and complexity relies on allelic diversity. Our results suggest that virtually unselected, nonuniform strains harbor a crucial proportion of neutral diversity and should be conserved with high global priority. As one example, we suggest a cooperative maintenance of the nondifferentiated, highly fragmented, and fast vanishing metapopulation of Balkan Buša.  相似文献   
82.
In advanced renal cell carcinoma (RCC), surgery combined with systemic chemotherapy and immunotherapy have had limited effectiveness. Therapeutic modalities targeting VEGF, PDGF, and c-kit using tyrosine kinase inhibitors and m-TOR using specific biologic factors are in development. Therapeutic approaches targeting TNF-alpha have shown limited efficacy, while anti-TRAIL (TNFSF10) antibodies have shown enhanced activity. The presence and potential significance of other members of the TNFSF has not been investigated. Here, we assayed the TNFSF members APRIL, BAFF, TWEAK and their receptors (BCMA, TACI, BAFFR, Fn14) in 86 conventional type clear cell RCC, using immunohistochemistry and correlated our findings with histological data and, in a limited series, follow-up of patients. We observed a differential expression of these TNFSF ligands and receptors in cancerous and non-cancerous structures. BAFF was found in all RCC; APRIL expression is associated with an aggressive phenotype, correlating negatively with patients' disease-free survival, while TWEAK and its receptor Fn14 are heterogeneously expressed, correlating negatively with the grade and survival of RCC patients. This is the first study, presenting together the TNFSF members APRIL, BAFF, TWEAK and their receptors in different areas of normal renal tissue and RCC, suggesting a potential role of these TNFSF members in renal tumor biology.  相似文献   
83.
Daedaleopsis confragosa belong to a large and remarkable group of mushrooms called polypores. This type of mushroom could be easily said to be quite unexplored and unused when it comes to its antioxidant properties. Thus, in order to evaluate its antioxidant activity, the investigation had to include the total phenolics and flavonoide content, the content of Selenium, the content of Zinc, the scavenging capacity on DPPH· and OH· radicals, reducing power and capacity to remove lipid peroxidation. The investigated mushroom extract contained 54.17 mg GAE/g of total phenols and 48.46 mg CE/g of total flavonoides. Zinc and Selenium were detected and quantified by using inductively coupled plasma mass spectroscopy. The scavenging activity of the radicals was found to exhibit 50% of the inhibition value (IC50 value) at the extract concentration of 0.015±0.007 mg/ml for the investigated D. confragosa extract. By using electron paramagnetic resonant spectroscopy it was found that the investigated extract does not have a significant role in the prevention of lipid peroxidation. It was effective in scavenging on ·OH radical, RI was 56±2%.  相似文献   
84.
Glioblastoma multiforme (GBM) is the most common and malignant form of glioma with high mortality and no cure. Many human cancers maintain a complex inflammatory program triggering rapid recruitment of inflammatory cells, including mast cells (MCs), to the tumor site. However, the potential contribution of MCs in glioma has not been addressed previously. Here we report for the first time that MCs infiltrate KRas+Akt-induced gliomas, using the RCAS/TV-a system, where KRas and Akt are transduced by RCAS into the brains of neonatal Gtv-a- or Ntv-a transgenic mice lacking Ink4a or Arf. The most abundant MC infiltration was observed in high-grade gliomas of Arf-/- mice. MC accumulation could be localized to the vicinity of glioma-associated vessels but also within the tumor mass. Importantly, proliferating MCs were detected, suggesting that the MC accumulation was caused by local expansion of the MC population. In line with these findings, strong expression of stem cell factor (SCF), i.e. the main MC growth factor, was detected, in particular around tumor blood vessels. Further, glioma cells expressed the MC chemotaxin CXCL12 and MCs expressed the corresponding receptor, i.e. CXCR4, suggesting that MCs could be attracted to the tumor through the CXCL12/CXCR4 axis. Supporting a role for MCs in glioma, strong MC infiltration was detected in human glioma, where GBMs contained significantly higher MC numbers than grade II tumors did. Moreover, human GBMs were positive for CXCL12 and the infiltrating MCs were positive for CXCR4. In conclusion, we provide the first evidence for a role for MCs in glioma.  相似文献   
85.
Studies have indicated that host inflammatory proteins, enzymes and indicators of bone metabolism present in saliva differ in different types of periodontal disease. However, the number of markers analyzed was limited and the effect of edentulousness was not examined. We measured the concentration of host inflammatory proteins: C-reactive protein (CRP), C3 and C4 complement components, alpha-2-macroglobulin (alpha-2M) and tumor-necrosis factor (TNF) in unstimulated saliva of 14 periodontally healthy (PH), 9 edentulous persons (EP), 10 patients with chronic periodontitis (CP) and 18 with aggressive periodontitis (AgP). TNF was below the level of detection in all samples except one. Edentulous persons and patients with CP had significantly reduced concentrations of CRP, C3 and alpha-2M. Edentulous persons and AgP patients had lower C4 concentrations. We can conclude that edentulous persons and CP patients have reduced salivary concentrations of host inflammatory proteins. These findings suggest that a reduction in host responsiveness might play a role in the pathogenesis of CP.  相似文献   
86.
The aim of this study was to evaluate the efficacy of botulinum toxin-A injections on motility disturbance in patients with dysthyroid eye disease. In 36 patients (52 orbits) with active phase of Grave's ophthalmopathy with motility disturbance, botulinum toxin-A injections were applied. Ocular motility was measured before and after treatment in four main directions (elevation, depression, abduction and adduction) with F?rster perimeter. In all patients 20 units of botulinum toxin-A in one single injection was applied in the projection of the inferior rectus muscle. Statistically, the degree of upgaze increased notably in all three groups, but mostly in the first group where it amounted up to 5.8-6.0 (z = 10.0;p = 0.68). We could not prove notable increase of the motility grade in the adduction in none of the groups of the tested patients. Due to the fact that eyeball motility can be objectively measured, effect of the applied therapy can be clearly evaluated.  相似文献   
87.
A synapse simulating model comprising of the nerve growth factor (NGF)-differentiated PC12 cells releasing neurotransmitter (NT) and sensor 92.1.7.human erythroleukemia (HEL) cells has been used for simulating the connection between neurons and target cells. A Ca(2+) elevation was observed in both cell types when the PC12 cells were challenged with nicotine. The response patterns of individual cell were subsequently analyzed mathematically. The Ca(2+) signals of the PC12 cells were described by an equation representing a simple bi-exponential function. The NT-noradrenaline discharged by the PC12 cells in response to nicotine caused heterogeneous secondary Ca(2+) elevations in the HEL cells after a certain delay. Model fitting of this response disclosed slow "hidden" oscillations and heterogeneous secondary Ca(2+) signals could be grouped on the basis of the oscillation frequency. As determined in control experiments with noradrenaline (NA), the value of oscillation frequency also revealed a good correlation with the NT concentration.  相似文献   
88.
The screening of microbial natural products continues to represent an important route to the discovery of novel chemicals for development of new therapeutic agents. The aim of this work was to develop an efficient method for the detection of immunosuppressive compounds produced by soil actinomycetes. Mutant strain of Saccharomyces cerevisiae, named FAV20, sensitive to FK506 was constructed by disrupting VMA22 gene using the selectable marker kanMX4 which allowed detection of integration events. Actinomycetes were isolated from different soil samples and in a newly developed test with S. cerevisiae FAV20, six strains have been identified that produce bioactive compounds with the same mechanism of action as FK506. S. cerevisiae FAV20 can be easily used as a test strain in drug screening programs based on inhibition of the calcineurin phosphatase dependent signaling pathway in the cell.  相似文献   
89.
The oxygen distribution in the microcirculation of the piglet’s brain and striatal extracellular dopamine were determined during repetitive apnea and resuscitation with 21% or 100% oxygen. Pre-apnea cortical oxygen was 49.5 ± 10.4 mm Hg and during each apnea decreased to 8 ± 0.9 mm Hg. After ten apneic episodes followed by resuscitation with 21% or 100% oxygen, 7.48 ± 1.6% or 2.6 ± 0.5% of the tissue volume was below 10 mm Hg, respectively. Extracellular dopamine increased progressively with an increase in the number of apneas with resuscitation of 21% oxygen and at the end of ten apneic episodes it was up to 59,500 ± 11,320% of control. There was no increase in extracellular dopamine during apnea resuscitated with 100% oxygen. Repetitive apnea caused progressive increase in fraction of hypoxic brain tissue in newborn. The magnitude of the increase is dependent on whether the animals were resuscitated with room air or 100% oxygen.  相似文献   
90.
Patel S  Brkljacic J  Gindullis F  Rose A  Meier I 《Planta》2005,222(6):1028-1040
Tomato MAF1 (LeMAF1) is a plant-specific, nuclear envelope (NE)-associated protein. It is the founding member of a group of WPP domain-containing, NE-associated proteins. This group includes the Arabidopsis WPP family, which is involved in cell division, as well as plant RanGAPs. In addition to its NE localization, LeMAF1 accumulates in speckles in the cytoplasm. Here, we show that the LeMAF1-containing speckles are components of the Golgi apparatus. A novel tomato coiled-coil protein was identified that specifically binds to LeMAF1. Tomato WPP domain-associated protein (LeWAP) interacts in yeast and in vitro through its coiled-coil domain with several WPP-domain containing proteins, including AtRanGAP1 and the WPP family (LeMAF, WPP1 and WPP2). Like LeMAF1, LeWAP is localized at the Golgi. Moreover, we present data showing that Arabidopsis WAP is necessary for the existence of a multi-protein complex containing WPP2. Electronic Supplementary Material Supplementary material is available for this article at .  相似文献   
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