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661.
The main hallmark of chronic kidney disease (CKD) is excessive inflammation leading to interstitial tissue fibrosis. It has been recently reported that NOV/CCN3 could be involved in kidney damage but its role in the progression of nephropathies is poorly known. NOV/CCN3 is a secreted multifunctional protein belonging to the CCN family involved in different physiological and pathological processes such as angiogenesis, inflammation and cancers. The purpose of our study was to determine the role of NOV/CCN3 in renal inflammation and fibrosis related to primitive tubulointerstitial injury. After unilateral ureteral obstruction (UUO), renal histology and real-time PCR were performed in NOV/CCN3-/- and wild type mice. NOV/CCN3 mRNA expression was increased in the obstructed kidneys in the early stages of the obstructive nephropathy. Interestingly, plasmatic levels of NOV/CCN3 were strongly induced after 7 days of UUO and the injection of recombinant NOV/CCN3 protein in healthy mice significantly increased CCL2 mRNA levels. Furthermore, after 7 days of UUO NOV/CCN3-/- mice displayed reduced proinflammatory cytokines and adhesion markers expression leading to restricted accumulation of interstitial monocytes, in comparison with their wild type littermates. Consequently, in NOV/CCN3-/- mice interstitial renal fibrosis was blunted after 15 days of UUO. In agreement with our experimental data, NOV/CCN3 expression was highly increased in biopsies of patients with tubulointerstitial nephritis. Thus, the inhibition of NOV/CCN3 may represent a novel target for the progression of renal diseases.  相似文献   
662.

Background

Functional (psychogenic) movement disorders (FMD) have features associated with voluntary movement (e.g. distractibility) but patients report movements to be out of their control. One explanation for this phenomenon is that sense of agency for movement is impaired. The phenomenon of reduction in the intensity of sensory experience when movement is self-generated and a reduction in sensory evoked potentials (SEPs) amplitude at the onset of self-paced movement (sensory attenuation) have been linked to sense of agency for movement.

Methods

We compared amplitude of SEPs from median nerve stimulation at rest and at the onset of a self-paced movement of the thumb in 17 patients with FMD and 17 healthy controls.

Results

Patients showed lack of attenuation of SEPs at the onset of movement compared to reduction in amplitude of SEPs in controls. FMD patients had significantly different ratios of movement onset to rest SEPs than did healthy controls at each electrode: 0.79 in healthy controls and 1.35 in patients at F3 (t = -4.22, p<0.001), 0.78 in healthy controls and 1.12 at patients C3 (t = -3.15, p = 0.004) and 0.77 in healthy controls and 1.05 at patients P3 (t = -2.88, p = 0.007).

Conclusions

Patients with FMD have reduced sensory attenuation as measured by SEPs at onset of self-paced movement. This finding can be plausibly linked to impairment of sense of agency for movement in these patients.  相似文献   
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Diazotrophic bacteria were isolated from the rhizosphere of field-grown Triticum aestivum, Hordeum vulgare, and Avena sativa grown in various regions of Greece. One isolate, with the highest nitrogen-fixation ability from each of the eleven rhizospheres, was selected for further characterisation. Diazotrophic strains were assessed for plant-growth-promoting traits such as indoleacetic acid production and phosphate solubilisation. The phylogenies of 16S rRNA gene of the selected isolates were compared with those based on dnaK and nifH genes. The constructed trees indicated that the isolates were members of the species Azospirillum brasilense, Azospirillum zeae, and Pseudomonas stutzeri. Furthermore, the ipdC gene was detected in all A. brasilence and one A. zeae isolates. The work presented here provides the first molecular genetic evidence for the presence of culturable nitrogen-fixing P. stutzeri and A. zeae associated with field-grown A. sativa and H. vulgare in Greece.  相似文献   
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To date there is a lack of tools to map the spatio-temporal dynamics of diverse cells in experimental heart models. Conventional histology is labor intensive with limited coverage, whereas many imaging techniques do not have sufficiently high enough spatial resolution to map cell distributions. We have designed and built a high resolution, dual channel Born-normalized near-infrared fluorescence optical projection tomography system to quantitatively and spatially resolve molecular agents distribution within whole murine heart. We validated the use of the system in a mouse model of monocytes/macrophages recruitment during myocardial infarction. While acquired, data were processed and reconstructed in real time. Tomographic analysis and visualization of the key inflammatory components were obtained via a mathematical formalism based on left ventricular modeling. We observed extensive monocyte recruitment within and around the infarcted areas and discovered that monocytes were also extensively recruited into non-ischemic myocardium, beyond that of injured tissue, such as the septum.  相似文献   
668.
Delignified cellulosic material has shown a significant promotional effect on the alcoholic fermentation as yeast immobilization support. However, its potential for further biotechnological development is unexploited. This study reports the characterization of this tubular/porous cellulosic material, which was done by SEM, porosimetry and X-ray powder diffractometry. The results showed that the structure of nano-tubular cellulose (NC) justifies its suitability for use in "cold pasteurization" processes and its promoting activity in bioprocessing (fermentation). The last was explained by a glucose pump theory. Also, it was demonstrated that crystallization of viscous invert sugar solutions during freeze drying could not be otherwise achieved unless NC was present. This effect as well as the feasibility of extremely low temperature fermentation are due to reduction of the activation energy, and have facilitated the development of technologies such as wine fermentations at home scale (in a domestic refrigerator). Moreover, NC may lead to new perspectives in research such as the development of new composites, templates for cylindrical nano-particles, etc.  相似文献   
669.
Chronic kidney disease is linked to systemic inflammation and to an increased risk of ischemic heart disease and atherosclerosis. Endothelial dysfunction associates with hypertension and vascular disease in the presence of chronic kidney disease but the mechanisms that regulate the activation of the endothelium at the early stages of the disease, before systemic inflammation is established remain obscure. In the present study we investigated the effect of serum derived from patients with chronic kidney disease either before or after hemodialysis on the activation of human endothelial cells in vitro, as an attempt to define the overall effect of uremic toxins at the early stages of endothelial dysfunction. Our results argue that uremic toxins alter the biological actions of endothelial cells and the remodelling of the extracellular matrix before signs of systemic inflammatory responses are observed. This study further elucidates the early events of endothelial dysfunction during toxic uremia conditions allowing more complete understanding of the molecular events as well as their sequence during progressive renal failure.  相似文献   
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