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1.

Aims

This study investigated Cu uptake and accumulation as well as physiological and biochemical changes in grapevines grown in soils containing excess Cu.

Methods

The grapevines were collected during two productive cycles from three vineyards with increasing concentrations of Cu in the soil and at various growth stages, before and after the application of Cu-based fungicides. The Cu concentrations in the grapevine organs and the macronutrients and biochemical parameters in the leaf blades were analyzed.

Results

At close to the flowering stage of the grapevines, the concentration and content of Cu in the leaves were increased. However, the Cu concentrations in the roots, stem, shoots and bunches did not correlate with the metal concentrations in the soil. The application of Cu-based fungicides to the leaves increased the Cu concentrations in the shoots, leaves and rachis; however, the effect of the fungicides on the Cu concentration in the berries was not significant. The biochemical analyses of the leaf blades demonstrated symptoms of oxidative stress that correlated with the Cu concentrations in soil.

Conclusions

The increased availability of Cu in soil had a slight effect on the levels and accumulation of Cu in mature grapevines during the productive season and did not alter the nutritional status of the plant. However, increased Cu concentrations were observed in the leaves. The evidence of oxidative stress in the leaves correlated with the increased levels of Cu in soil.  相似文献   
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Pericytes are CD146+ perivascular cells (PCs) that have multipotential differentiation capacity as mesenchymal stem cells. Beside their crucial roles in vascular development and blood flow regulation, they have ability to differentiate into vascular cell types in vivo. These properties make pericytes preferred cells in the field of vascular tissue engineering. Culture medium for in vitro differentiation of pericytes to vascular smooth muscle cells (SMCs) has not been defined yet. The aim of this study is to try different culture media for SMC differentiation of CD146+ PCs. For this purpose, CD146+ PCs were isolated from human umbilical cord vein. Then they were characterized by immunofluorescence staining and flow cytometric analysis. Three different culture media including; (1) Transforming growth factor beta 1 (TGF-β1)+ bone morphogenic protein 4, (2) TGF-β1+ l-ascorbic acid (l-AA) and (3) Horse serum, were compared for differentiation of CD146+ PCs to SMCs by IFS and real time polymerase chain reaction. As a result, in the case of SMC differentiation of CD146+ PCs, second culture medium including TGF-β1 and l-AA was found to be more effective than other two media. These results are important for establishing proper culture conditions for in vitro SMC differentiation of CD146+ PCs.  相似文献   
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Zonula Occludens (ZO) proteins are ubiquitous scaffolding proteins providing the structural basis for the assembly of multiprotein complexes at the cytoplasmic surface of the plasma membrane and linking transmembrane proteins to the filamentous cytoskeleton. They belong to the large family of membrane-associated guanylate kinase (MAGUK)-like proteins comprising a number of subfamilies based on domain content and sequence similarity. ZO proteins were originally described to localize specifically to tight junctions, or Zonulae Occludentes, but this notion was rapidly reconsidered since ZO proteins were found to associate with adherens junctions as well as with gap junctions, particularly with connexin-made intercellular channels, and also with a few other membrane channels. Accumulating evidence reveals that in addition to having passive scaffolding functions in organizing gap junction complexes, including connexins and cytoskeletals, ZO proteins (particularly ZO-1) also actively take part in the dynamic function as well as in the remodeling of junctional complexes in a number of cellular systems. This article is part of a Special Issue entitled: Reciprocal influences between cell cytoskeleton and membrane channels, receptors and transporters. Guest Editor: Jean Claude Hervé.  相似文献   
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Background

Radiotherapy is one of the most important treatments of primary and metastatic brain tumors. Unfortunately, it can involve moderate to severe complications among which leukoencephalopathy is very frequent and implies cognitive deficits such as memory, attention and executive dysfunctions. However, the incidence of this complication is not well established and the risk factors and process are poorly understood. The main objective of the study is to improve knowledge on radio-induced leukoencephalopathy based on pluridisciplinar approaches combining cognitive, biologic, imagery and dosimetric investigations.

Method/Design

The EpiBrainRad study is a prospective cohort study including newly diagnosed high grade gliomas patients treated by radiotherapy and concomitant-adjuvant temozolomide chemotherapy. Patients are included between their surgery and first day of radio-chemotherapy, and the follow-up lasts for 3 years after treatment. Cognitive functioning assessments, specific blood biomarkers measures and magnetic resonance imagery are performed at different moment during the follow-up, and a specific dosimetric assessment of organs involved in the beam fields is performed. Firstly, leukoencephalopathy incidence rate will be estimated in this population. Secondly, correlations between cognitive impairments and dosimetry, biomarkers ranges and anomalies on imagery will be analyzed in order to better understand the onset and evolution of cognitive decrement associated with radiotherapy. Furthermore, a new cognitive test, quickly and easily performed, will be studied to determine its sensibility to detect leukoencephalopathy decrement.

Discussion

With an original multidisciplinary approach, the EpiBrainRad study aims to improve knowledge on radio-induced leukoencephalopathy in order to improve its early diagnosis and prevention. The main challenge is to preserve quality-of-life after cancer treatments which imply to study the incidence of radiation-induced complications and their associated risk factors.

Trial Registration

NCT02544178
  相似文献   
9.
Regeneration of the lung airway epithelium after injury has been extensively studied. In contrast, analysis of its turnover in healthy adulthood has received little attention. In the classical view, this epithelium is maintained in the steady‐state by the infrequent proliferation of basal or Clara cells. The intermediate filament protein nestin was initially identified as a marker for neural stem cells, but its expression has also been detected in other stem cells. Lungs from CD1 mice at the age of 2, 6, 12, 18 or 24 months were fixed in neutral‐buffered formalin and paraffin‐embedded. Nestin expression was examined by an immunohistochemical peroxidase‐based method. Nestin‐positive cells were detected in perivascular areas and in connective tissue that were in close proximity of the airway epithelium. Also, nestin‐positive cells were found among the cells lining the airway epithelium. These findings suggest that nestin‐positive stem cells circulate in the bloodstream, transmigrate through blood vessels and localize in the lung airway epithelium to participate in its turnover. We previously reported the existence of similar cells able to differentiate into lung chondrocytes. Thus, the stem cell reported here might be a bone marrow‐derived mesenchymal stem cell (BMDMSC) able to generate several types of lung tissues. In conclusion, our findings indicate that there exist a BMDMSC in healthy adulthood that participates in the turnover of the lung airway epithelium. These findings may improve our knowledge about the lung stem cell biology and also provide novel approaches to therapy for devastating pulmonary diseases.  相似文献   
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Volatile organic compounds (VOCs) are secondary metabolites acting as a language for the communication of plants with the environment. In orange fruits, the monoterpene D-limonene accumulates at very high levels in oil glands from the peel. Drastic down-regulation of D-limonene synthase gene expression in the peel of transgenic oranges harboring a D-limonene synthase transgene in antisense (AS) configuration altered the monoterpene profile in oil glands, mainly resulting in reduced accumulation of D-limonene. This led to fruit resistance against Penicillium digitatum (Pd), Xanthomonas citri subsp. citri (Xcc) and other specialized pathogens. Here, we analyze resistance to pathogens in independent AS and empty vector (EV) lines, which have low, medium or high D-limonene concentrations and show that the level of resistance is inversely related to the accumulation of D-limonene in orange peels, thus explaining the need of high D-limonene accumulation in mature oranges in nature for the efficient attraction of specialized microorganism frugivores.  相似文献   
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