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Endothelium specific matrilysin (MMP-7) expression in human cancers.   总被引:1,自引:0,他引:1  
Over-expression of matrilysin (MMP-7) is predominantly associated with epithelial (pre)malignant cells. In the present study MMP-7 expression is also found in endothelial cells in various human cancer types. Endothelial MMP-7 was associated with CD34 and/or CD105 expression. These immunohistochemical data were confirmed by RT-PCR on VEGF-stimulated endothelial cells. In addition, MMP-7 was also identified in sprouting endothelial cells in vitro. The potential clinical relevance of endothelial MMP-7 was assessed for cervical cancer patients by evaluating the association with overall survival. In contrast to MMP-7 in malignant epithelial cells, MMP-7 expression in endothelial cells showed a significant association with poor survival (LR 5.12, P=0.02, n=30). Our data suggest that MMP-7 is involved in tumor angiogenesis, thereby contributing to malignant growth and hence associated with decreased survival.  相似文献   
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Monocytes attracted by tumor-induced chronic inflammation differentiate to APCs, the type of which depends on cues in the local tumor milieu. In this work, we studied the influence of human cervical cancer cells on monocyte differentiation and showed that the majority of cancer cells either hampered monocyte to dendritic cell differentiation or skewed their differentiation toward M2-like macrophages. Blocking studies revealed that M2 differentiation was caused by tumor-produced PGE(2) and IL-6. TGF-β, IL-10, VEGF, and macrophage colony-stimulating factor did not play a role. Notably, these CD14(+)CD163(+) M2 macrophages were also detected in situ. Activation of cancer cell-induced M2-like macrophages by several TLR-agonists revealed that compared with dendritic cells, these M2 macrophages displayed a tolerogenic phenotype reflected by a lower expression of costimulatory molecules, an altered balance in IL-12p70 and IL-10 production, and a poor capacity to stimulate T cell proliferation and IFN-γ production. Notably, upon cognate interaction with Th1 cells, these tumor-induced M2 macrophages could be switched to activated M1-like macrophages that expressed high levels of costimulatory molecules, produced high amounts of IL-12 and low amounts of IL-10, and acquired the lymphoid homing marker CCR7. The effects of the interaction between M2 macrophages and Th1 cells could partially be mimicked by activation of these APCs via CD40 in the presence of IFN-γ. Our data on the presence, induction, and plasticity of tumor-induced tolerogenic APCs in cervical cancer suggest that tumor-infiltrated Th1 cells can stimulate a tumor-rejecting environment by switching M2 macrophages to classical proinflammatory M1 macrophages.  相似文献   
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A hallmark of voluntary motor control is the ability to stop an ongoing movement. Is voluntary motor inhibition a general neural mechanism that can be focused on any movement, including involuntary movements, or is it mere termination of a positive voluntary motor command? The involuntary arm lift, or ‘floating arm trick’, is a distinctive long-lasting reflex of the deltoid muscle. We investigated how a voluntary motor network inhibits this form of involuntary motor control. Transcranial magnetic stimulation of the motor cortex during the floating arm trick produced a silent period in the reflexively contracting deltoid muscle, followed by a rebound of muscle activity. This pattern suggests a persistent generator of involuntary motor commands. Instructions to bring the arm down voluntarily reduced activity of deltoid muscle. When this voluntary effort was withdrawn, the involuntary arm lift resumed. Further, voluntary motor inhibition produced a strange illusion of physical resistance to bringing the arm down, as if ongoing involuntarily generated commands were located in a ‘sensory blind-spot’, inaccessible to conscious perception. Our results suggest that voluntary motor inhibition may be a specific neural function, distinct from absence of positive voluntary motor commands.  相似文献   
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Genetic factors play an important role in the pathogenesis of osteoporosis. The genes involved are, however, still largely unknown. In the present study, we have investigated whether sequence variations in the estrogen receptor beta (ERbeta) gene are associated with bone mineral density (BMD) and biochemical markers of bone turnover in 79 Slovenian postmenopausal women with osteoporosis. We also assessed the response by BMD and bone markers to antiresorptive therapy with bisphosphonate alendronate. All eight exons of ERbeta gene were amplified by polymerase chain reaction and screened for mutations by single-strand conformation polymorphism analysis. Potentially mutated samples were found only in exon 5 and sequence analysis identified the presence of a silent mutation in codon 328 with a nucleotide substitution GTG to GTA. For easier detection of this silent mutation, the RsaI restriction fragment length polymorphism analysis was developed. The frequencies of genotypes were as follows: Rr 5.1% and RR 94.9%. Between both genotypes, no significant differences in baseline lumbar spine and femoral neck BMD or in bone markers osteocalcin and deoxypyridinoline were observed. Similarly, no significant difference between RR and Rr genotypes in BMD or bone markers after 1 year of therapy was found. The increase in lumbar spine BMD after therapy was the only parameter that approached statistical significance (P=0.099). Patients with genotype Rr showed a smaller increase compared to those with RR. Our results suggest that RsaI polymorphism of ERbeta gene is probably not an important genetic determinant of BMD and does not significantly influence the responsiveness to alendronate therapy.  相似文献   
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  1. Shrub encroachment in seminatural grasslands threatens local biodiversity unless management is applied to reduce shrub density. Dense vegetation of Cytisus scoparius homogenizes the landscape negatively affecting local plant diversity. Detecting structural change (e.g., biomass) is essential for assessing negative impacts of encroachment. Hence, exploring new monitoring tools to achieve this task is important for effectively capturing change and evaluating management activities.
  2. This study combines traditional field‐based measurements with novel Light Detection and Ranging (LiDAR) observations from an Unmanned Aircraft System (UAS). We investigate the accuracy of mapping C. scoparius in three dimensions (3D) and of structural change metrics (i.e., biomass) derived from ultrahigh‐density point cloud data (>1,000 pts/m2). Presence–absence of 12 shrub or tree genera was recorded across a 6.7 ha seminatural grassland area in Denmark. Furthermore, 10 individuals of C. scoparius were harvested for biomass measurements. With a UAS LiDAR system, we collected ultrahigh‐density spatial data across the area in October 2017 (leaf‐on) and April 2018 (leaf‐off). We utilized a 3D point‐based classification to distinguish shrub genera based on their structural appearance (i.e., density, light penetration, and surface roughness).
  3. From the identified C. scoparius individuals, we related different volume metrics (mean, max, and range) to measured biomass and quantified spatial variation in biomass change from 2017 to 2018. We obtained overall classification accuracies above 86% from point clouds of both seasons. Maximum volume explained 77.4% of the variation in biomass.
  4. The spatial patterns revealed landscape‐scale variation in biomass change between autumn 2017 and spring 2018, with a notable decrease in some areas. Further studies are needed to disentangle the causes of the observed decrease, for example, recent winter grazing and/or frost events.
  5. Synthesis and applications: We present a workflow for processing ultrahigh‐density spatial data obtained from a UAS LiDAR system to detect change in C. scoparius. We demonstrate that UAS LiDAR is a promising tool to map and monitor grassland shrub dynamics at the landscape scale with the accuracy needed for effective nature management. It is a new tool for standardized and nonbiased evaluation of management activities initiated to prevent shrub encroachment.
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The stability of species and provenance performance across diverse environments is a major issue in restoration, particularly for assisted migration and climate‐adjusted provenancing strategies. This study examines how differences in species and provenance performance are affected by plant community composition in a dry sclerophyll forest restoration experiment. Five indices were measured over 6 years post‐establishment to evaluate the relative performance of community composition using 10 provenances of two focal eucalypts (Eucalyptus pauciflora and Eucalyptus tenuiramis) under six community treatments for E. pauciflora and five for E. tenuiramis. Community treatments varied according to the species planted as the immediate neighbor to the focal species, and included same species, same genus, or one of three different genera. Significant species and provenance differences were observed for all measured performance indices, with no evidence of interaction effects with community treatments. E. tenuiramis was more susceptible to insects and frost, and had poorer establishment but greater growth of the survivors than E. pauciflora. Generally, nonlocal provenances were more susceptible to insect herbivory and frost damage and had higher mortality than local provenances. At this early life‐stage there was no evidence that co‐planted species affected the relative performance of focal species or provenances, arguing transfer functions are likely stable across different planted communities. While species and provenance performance was not affected by community context, focal species differed in their response to upslope migration and any climate‐adjusted provenancing may require staged transfers to avoid maladaptation under contemporary growing conditions.  相似文献   
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Prenatal exposure to neurotoxicants such as lead (Pb) may cause stable changes in the DNA methylation (5mC) profile of the fetal genome. However, few studies have examined its effect on the DNA de-methylation pathway, specifically the dynamic changes of the 5-hydroxymethylcytosine (5hmC) profile. Therefore, in this study, we investigate the relationship between Pb exposure and 5mC and 5hmC modifications during early development. To study the changes in the 5hmC profile, we use a novel modification of the Infinium™ HumanMethylation450 assay (Illumina, Inc.), which we named HMeDIP-450K assay, in an in vitro human embryonic stem cell model of Pb exposure. We model Pb exposure-associated 5hmC changes as clusters of correlated, adjacent CpG sites, which are co-responding to Pb. We further extend our study to look at Pb-dependent changes in high density 5hmC regions in umbilical cord blood DNA from 48 mother-infant pairs from the Early Life Exposure in Mexico to Environmental Toxicants (ELEMENT) cohort. For our study, we randomly selected umbilical cord blood from 24 male and 24 female children from the 1st and 4th quartiles of Pb levels. Our data show that Pb-associated changes in the 5hmC and 5mC profiles can be divided into sex-dependent and sex-independent categories. Interestingly, differential 5mC sites are better markers of Pb-associated sex-dependent changes compared to differential 5hmC sites. In this study we identified several 5hmC and 5mC genomic loci, which we believe might have some potential as early biomarkers of prenatal Pb exposure.  相似文献   
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