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991.
Objectives: Myofibroblasts are a vital component of stroma of many malignant neoplasms, but it is not yet established whether stromal myofibroblasts also exist in benign tumours such as oncocytoma of the kidney. Materials and methods: Histomorphological and immunohistochemical analysis of 16 renal oncocytomas diagnosed at Chang Gung Memorial Hospital, Taiwan, has been performed. Results: Renal oncocytomas were composed of oncocytes, large cells with granular eosinophilic cytoplasm, arranged mostly in sheets, in tubulocystic or combined pattern. Few oncocytes appeared to be undergoing proliferation or apoptosis. MIB‐1 and active caspase 3 indices were low, but higher in tumour than in surrounding non‐tumour parenchyma (MIB‐1: 0.93 ± 0.09 versus 0.46 ± 0.07, P < 0.001 and active caspase 3: 0.76 ± 0.08 versus 0.41 ± 0.09, P < 0.001). Wnt/β‐catenin signalling was not implicated in this neoplasm, as there was no loss of E‐cadherin membranous localization or expression of intranuclear β‐catenin in the cells. Clumps of oncocytes were stained with periodic acid Schiff and had collagen I‐, collagen III‐ and fibronectin‐positive, but desmin‐ and human caldesmon‐negative stromas. Importantly, α‐smooth muscle actin (SMA)‐immunostaining established the myofibroblastic nature of many of the stromal cells. Some of the myofibroblasts were also positive for MIB‐1, indicating a proliferative role for them in the stroma. Conclusions: Renal oncocytomas were composed of two independent compartments: benign oncocytes and pronounced fibrotic stroma, which consisted of proliferating myofibroblasts (SMA‐ and MIB‐1‐positive) which were associated with excessive deposition of extracellular matrix (periodic acid Schiff‐component, collagen I‐, collagen III‐ and fibronectin‐positive, and desmin‐ and human caldesmon‐negative).  相似文献   
992.
Urbanization, one of the most extreme land‐use alterations, is currently spreading, and the number of species confronting these changes is increasing. However, contradictory results of previous studies impede a clear interpretation of which selective pressure (nest predation or food limitation) is more important in urban habitats compared with natural situations, and whether birds can confront them by adjusting their life‐history strategies. We investigated life‐history syndromes of three common blackbird (Turdus merula) populations differing in their human influence (urban, rural, and woodland). We analysed daily nest predation and nestling starvation rates to assess the relative importance of these selection pressures in each habitat. Simultaneously, several life‐history traits were investigated to determine if T. merula seem adapted to their main source of selection. Food limitation was more important in the city, whereas nest predation was the most important selective force in the forest. The rural habitat was characterized by an intermediate influence of these two factors. Life‐history syndromes, as the covariation of a suite of traits, confirmed these results because T. merula seem well adapted to the main cause of selection in each habitat. Our results are consistent with urbanization imposing new challenges on birds, and that they adaptively respond to them. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 101 , 759–766.  相似文献   
993.
Analysis of the retinal defects of a CK2 phosphomimetic variant of E(spl)M8 (M8S159D) and the truncated protein M8* encoded by the E(spl)D allele, suggest that the nonphosphorylated CtD “autoinhibits” repression. We have investigated this model by testing for inhibition (in “trans”) by the CtD fragment in its nonphosphorylated (M8‐CtD) and phosphomimetic (M8SD‐CtD) states. In N+ flies, ectopic M8‐CtD compromises lateral inhibition, i.e., elicits supernumerary bristles as with loss of N signaling. This antimorphic activity of M8‐CtD strongly rescues the reduced eye and/or bristle loss phenotypes that are elicited by ectopic M8SD or wild type M8. Additionally, the severely reduced eye of Nspl/Y; E(spl)D/+ flies is also rescued by M8‐CtD. Rescue is specific to the time and place, the morphogenetic furrow, where “founding” R8 photoreceptors are specified. In contrast, the phosphomimetic M8SD‐CtD that is predicted to be deficient for autoinhibition, exhibits significantly attenuated or negligible activity. These studies provide evidence that autoinhibition by the CtD regulates M8 activity in a phosphorylation‐dependent manner. genesis 48:44–55, 2010. © 2009 Wiley‐Liss, Inc.  相似文献   
994.
Increases in revegetation activities have created a large demand for locally adapted native plant materials (NPM) in the southwestern United States. Currently, there is a minimal supply of local genotypes to meet this demand. We investigated the potential for the initiation of a native plant market in the southern Colorado Plateau. Through a literature search, interviews, and site visits, we identified existing native plant markets outside of the region as useful models to help initiate a regional market. We used web‐based surveys to identify and analyze current and future NPM needs and concerns. Survey results indicate that management policy strongly drives decisions regarding the use and purchase of NPM. From a demand perspective , lack of availability and cost of NPM has kept purchasing minimal, despite policy changes favoring the use of natives. For suppliers, further development of NPM is limited by inconsistent and unreliable demand and lack of production knowledge. The knowledge and tools necessary to initiate an NPM market are available, but inadequate funding sources and insufficient information sharing hinder its development. Communication among producers, land managers, buyers, and researchers, as well as partnerships with local growers, appear to be vital to initiating a functional market.  相似文献   
995.
996.
Most of our bones form through the process of endochondral ossification, which is tightly regulated by the activity of the cartilage growth plate. Chondrocyte maturation through the various stages of growth plate physiology ultimately results in hypertrophy. Chondrocyte hypertrophy is an essential contributor to longitudinal bone growth, but recent data suggest that these cells also play fundamental roles in signaling to other skeletal cells, thus coordinating endochondral ossification. On the other hand, ectopic hypertrophy of articular chondrocytes has been implicated in the pathogenesis of osteoarthritis. Thus, a better understanding of the processes that control chondrocyte hypertrophy in the growth plate as well as in articular cartilage is required for improved management of both skeletal growth disorders and osteoarthritis. This review summarizes recent findings on the regulation of hypertrophic chondrocyte differentiation, the cellular mechanisms involved in hypertrophy, and the role of chondrocyte hypertrophy in skeletal physiology and pathophysiology. Birth Defects Research (Part C) 102:74–82, 2014. © 2014 Wiley Periodicals, Inc.  相似文献   
997.
The use of ionic liquids (ILs) as reaction media for enzymatic reactions has increased their potential because they can improve enzyme activity and stability. Kinetic and stability properties of immobilized commercial laccase from Myceliophthora thermophila in the water‐soluble IL 1‐ethyl‐3‐methylimidazolium ethylsulfate ([emim][EtSO4]) have been studied and compared with free laccase. Laccase immobilization was carried out by covalent binding on glyoxyl–agarose beads. The immobilization yield was 100%, and the activity was totally recovered. The Michaelis‐Menten model fitted well to the kinetic data of enzymatic oxidation of a model substrate in the presence of the IL [emim][EtSO4]. When concentration of the IL was augmented, the values of Vmax for free and immobilized laccases showed an increase and slight decrease, respectively. The laccase–glyoxyl–agarose derivative improved the laccase stability in comparison with the free laccase regarding the enzymatic inactivation in [emim][EtSO4]. The stability of both free and immobilized laccase was slightly affected by small amounts of IL (<50%). A high concentration of the IL (75%) produced a large inactivation of free laccase. However, immobilization prevented deactivation beyond 50%. Free and immobilized laccase showed a first‐order thermal inactivation profile between 55 and 70°C in the presence of the IL [emim][EtSO4]. Finally, thermal stability was scarcely affected by the presence of the IL. © 2014 American Institute of Chemical Engineers Biotechnol. Prog., 30:790–796, 2014  相似文献   
998.
Multiple sclerosis (MS) is a chronic auto‐immune disease characterized by a damage to the myelin component of the central nervous system. Self‐antigens created by aberrant glycosylation have been described to be a key component in the formation of auto‐antibodies. CSF114(Glc) is a synthetic glucopeptide detecting in vitro MS‐specific auto‐antibodies, and it is actively used in diagnostics and research to monitor and quantify MS‐associated Ig levels. We reasoned that antibodies raised against this probe could have been relevant for MS. We therefore screened a human Domain Antibody library against CSF114(Glc) using magnetic separation as a panning method. We obtained and described several clones, and the one with the highest signals was produced as a 6×His‐tagged protein to properly study the binding properties as a soluble antibody. By surface plasmon resonance measurements, we evidenced that our clone recognized CSF114(Glc) with high affinity and specific for the glucosylated peptide. Kinetic parameters of peptide–clone interaction were calculated obtaining a value of KD in the nanomolar range. Harboring a human framework, this antibody should be very well tolerated by human immune system and may represent a valuable tool for MS diagnosis and therapy, paving the way to new research strategies. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
999.
The binding affinity between a nuclear localization signal (NLS) and its import receptor is closely related to corresponding nuclear import activity. PTM‐based modulation of the NLS binding affinity to the import receptor is one of the most understood mechanisms to regulate nuclear import of proteins. However, identification of such regulation mechanisms is challenging due to the difficulty of assessing the impact of PTM on corresponding nuclear import activities. In this study we proposed NIpredict, an effective algorithm to predict nuclear import activity given its NLS, in which molecular interaction energy components (MIECs) were used to characterize the NLS‐import receptor interaction, and the support vector regression machine (SVR) was used to learn the relationship between the characterized NLS‐import receptor interaction and the corresponding nuclear import activity. Our experiments showed that nuclear import activity change due to NLS change could be accurately predicted by the NIpredict algorithm. Based on NIpredict, we developed a systematic framework to identify potential PTM‐based nuclear import regulations for human and yeast nuclear proteins. Application of this approach has identified the potential nuclear import regulation mechanisms by phosphorylation of two nuclear proteins including SF1 and ORC6. Proteins 2014; 82:2783–2796. © 2014 Wiley Periodicals, Inc.  相似文献   
1000.
Araucaria araucana (Araucaria) is a long‐lived conifer growing along a sharp west–east biophysical gradient in the Patagonian Andes. The patterns and climate drivers of Araucaria growth have typically been documented on the driest part of the gradient relying on correlations with meteorological records, but the lack of in situ soil moisture observations has precluded an assessment of the growth responses to soil moisture variability. Here, we use a network of 21 tree‐ring width chronologies to investigate the spatiotemporal patterns of tree growth through the entire gradient and evaluate their linkages with regional climate and satellite‐observed surface soil moisture variability. We found that temporal variations in tree growth are remarkably similar throughout the gradient and largely driven by soil moisture variability. The regional spatiotemporal pattern of tree growth was positively correlated with precipitation (r = 0.35 for January 1920–1974; P < 0.01) and predominantly negatively correlated with temperature (r = ?0.38 for January–March 1920–1974; P < 0.01) during the previous growing season. These correlations suggest a temporally lagged growth response to summer moisture that could be associated with known physiological carry‐over processes in conifers and to a response to moisture variability at deeper layers of the rooting zone. Notably, satellite observations revealed a previously unobserved response of Araucaria growth to summer surface soil moisture during the current rather than the previous growing season (r = 0.65 for 1979–2000; P < 0.05). This new response has a large spatial footprint across the mid‐latitudes of the South American continent (35°–45°S) and highlights the potential of Araucaria tree rings for palaeoclimatic applications. The strong moisture constraint on tree growth revealed by satellite observations suggests that projected summer drying during the coming decades may result in regional growth declines in Araucaria forests and other water‐limited ecosystems in the Patagonian Andes.  相似文献   
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