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11.
Differential expression of MMP-2/MMP-9 and potential benefit of an MMP inhibitor in experimental acute kidney allograft rejection 总被引:4,自引:0,他引:4
Acute cellular allograft rejection is characterized by leukocyte invasion and tissue destruction, associated with qualitative and quantitative alterations in the extracellular matrix (ECM) compartment. Metabolism of ECM proteins is mainly regulated by matrix metalloproteinases (MMP), that are zinc depended endoproteinases. MMP, especially basement membrane degrading MMP-2 and MMP-9, also facilitate tissue invasion of leukocytes. In addition, MMP-2 exerts a direct pro-inflammatory effect upon glomerular mesangial cells. Therefore, the investigation of the role of MMP in transplant rejection may lead to novel approaches in the therapy of rejection processes. To our knowledge, this is the first study of acute allograft rejection, formally addressing expression and activity of MMP, including the effect of a MMP inhibiting agent. For our studies, we used the orthotopic kidney allograft model in the stringent Dark Agouti-to-Lewis rat strain combination. Animals were divided into four groups: group A, healthy untreated Lewis rats (n=3); group B, sham operated Lewis rats (n=3); group C, transplanted Lewis rats treated with vehicle solution only (n=12); group D, transplanted Lewis rats treated with MMP inhibitor BB-94 (n=12). Respective animals were treated once daily intraperitonealy with BB-94 (30 mg/kg) or vehicle solution only. Treatment lasted from the third preoperative day until the end of the experiment, the time of severe rejection at day +7. Acute kidney allograft rejection led to alterations in the expression and activity of MMP. Overall MMP activity slightly increased despite severe destruction of kidney histology. The MMP inhibitor BB-94 successfully inhibited MMP activity to a high extent. MMP expression did not show uniform findings, since acute rejection led to differential expression of MMP-2 and MMP-9. During the rejection process, MMP-9 showed a small but significant increase, whereas MMP-2 production decreased substantially. Interestingly, BB-94 was able to keep proteinuria at a low level in transplanted animals. In conclusion, MMP-especially MMP-9-appear to represent new mediators involved in acute kidney transplant rejection. 相似文献
12.
Nicolas-Robin A Salvi N Medimagh S Amour J Le Manach Y Coriat P Riou B Langeron O 《Intensive care medicine》2007,33(6):986-992
Objective Brain death may induce cardiac dysfunction. In potential organ donors measurements of N-terminal pro-brain natriuretic peptide
(NT-proBNP) and circulating cardiac troponins T and I (cTnT and cTnI), alone or in combination, are performed to investigate
the accuracy of these biomarkers for early diagnosis of left ventricular systolic dysfunction.
Design and setting Prospective study in a multidisciplinary intensive care unit of an university hospital.
Patients 63 brain-dead patients scheduled for multiple organ harvesting.
Measurements and results We measured NT-proBNP, cTnT, and cTnI and determined fractional area change (FAC) using transesophageal echocardiography.
Forty-five patients had normal FAC, 9 a moderate decrease in FAC (30–50), and 9 a severe decrease in FAC (≤ 30%). NT-proBNP
and cTnT concentrations were significantly higher in patients with a severe decrease in FAC than in those with a moderate
decrease. Combining measurements of these two biomarkers, the sensitivity of the test to predict severe decrease in FAC increased
significantly to reach 1.00 compared with the sensitivities of individual measurements. The ROC curve area of combined measurements
of NT-proBNP and cTnT was significantly higher than single measurements: 0.87 vs. 0.82 for NT-proBNP, 0.78 for cTnT, and 0.72
for cTnI.
Conclusions In potential organ donors the combined measurement of NT-proBNP and cTnT concentrations is more accurate than individual measurement
of NT-proBNP, cTnT, and cTnI in the early diagnosis of severe left ventricular systolic dysfunction. These findings may lead
to improve the quality of cardiac care of the potential organ donors. 相似文献
13.
The synthetic opioid methadone has generated much interest in recent years among clinicians involved in the management of intractable chronic cancer pain. Its use as an analgesic is starting to extend to the treatment of noncancer pain, particularly neuropathic pain. Unfortunately, the evidence for its use in the management of neuropathic pain is limited to a few case studies. We examined retrospectively during a 12-month study period the clinical response of all 13 patients at our pain clinic who were prescribed methadone in an attempt to control neuropathic pain resistant to conventional analgesics. A questionnaire was also administered to the 9 patients who continued to take methadone at 12 months posttreatment. A total of 4 patients (31%) discontinued it by the end of the 12-month study period. Patients discontinued methadone due to the absence of pain relief and due to various intractable, undesirable side effects. Somnolence was the most common adverse effect reported, followed by nausea, constipation, and vomiting. All patients took coanalgesics (eg, amitriptyline, gabapentin) or other analgesics (eg, morphine, nonsteroidal anti-inflammatory drugs) during methadone treatment to control pain. The 9 patients who continued to take methadone at 12 months reported experiencing on average 43% pain relief (range 0-80%), 47% improvement in quality of life (range 0-100%), and 30% improvement in quality of sleep (range 0-60%). Methadone was effective at relieving pain and ameliorating quality of life and sleep in 62% of patients. These findings suggest that methadone can offer an acceptable success rate for the treatment of neuropathic pain. Prospective randomized, placebo-controlled studies are now needed to examine more rigorously the benefits of methadone for this type of pain. 相似文献
14.
15.
Nadège Limousin MD Eric Konofal MD PhD Elias Karroum MD Ebba Lohmann MD Ioannis Theodorou MD PhD Alexandra Dürr MD PhD Isabelle Arnulf MD PhD 《Movement disorders》2009,24(13):1970-1976
Parkin gene mutations cause a juvenile parkinsonism. Patients with these mutations may commonly exhibit REM sleep behaviour disorders, but other sleep problems (insomnia, sleepiness, restless legs syndrome) have not been studied. The aim of this study was to evaluate the sleep‐wake phenotype in patients with two parkin mutations, compared with patients with idiopathic Parkinson's disease (iPD). Sleep interview and overnight video‐polysomnography, followed by multiple sleep latency tests, were assessed in 11 consecutive patients with two parkin mutations (aged 35–60 years, from seven families) and 11 sex‐matched patients with iPD (aged 51–65 years). Sleep complaints in the parkin group included insomnia (73% patients versus 45% in the iPD group), restless legs syndrome (45%, versus none in the iPD group, P = 0.04), and daytime sleepiness (45%, versus 54% in the iPD group). Of the parkin patients, 45% had REM sleep without atonia, but only 9% had a definite REM sleep behavior disorder. All sleep measures were similar in the parkin and iPD groups. Two parkin siblings had a central hypersomnia, characterized by mean daytime sleep latencies of 3 min, no sleep onset REM periods, and normal nighttime sleep. Although the patients with two parkin mutations were young, their sleep phenotype paralleled the clinical and polygraphic sleep recording abnormalities reported in iPD, except that restless legs syndrome was more prevalent and secondary narcolepsy was absent. © 2007 Movement Disorder Society 相似文献
16.
Metellus P Voutsinos-Porche B Nanni-Metellus I Colin C Fina F Berenguer C Dussault N Boudouresque F Loundou A Intagliata D Chinot O Martin PM Figarella-Branger D Ouafik L 《European journal of cancer (Oxford, England : 1990)》2011,47(11):1727-1735
Clinical and experimental studies suggest that angiogenesis is a prerequisite for solid tumour growth. Glioblastoma (GBM) and pilocytic astrocytoma (PA), both angiogenic tumours display strong contrast enhancement associated with peripheral oedema in GBM but not in PA indicating differences in vascular permeability in these two types of gliomas. Here we show that expression of adrenomedullin (AM) mRNA is induced in GBM whereas is barely detectable in PA. In situ analysis of tumour specimens undergoing neovascularisation shows that the production of AM is specifically induced in a subset of GBM cells distinguished by their immediate proximity to necrotic foci (presumably hypoxic regions), suggesting a hypoxic induction of AM expression in GBM. Vascular endothelial growth factor (VEGF) mRNA levels are increased in GBM and moderate in PA. Immunohistochemical study showed that cytoplasmic AM, VEGF and HIF-1α nuclear immunoreactivity were recorded in GBM located near large necrotic areas whereas they were not expressed by PA tumour cells. Interestingly, double fluorescence immunostaining demonstrated that 85% of AM immunoreactivity colocalised with VEGF. AM transduces its effects through calcitonin receptor-like receptor/receptor activity modifying protein-2 and -3 (CLR/RAMP2 and CLR/RAMP3). Real-time quantitative RT-PCR showed expression of RAMP2, RAMP3 and CLR in PA and GBM, suggesting that AM may function as an autocrine/paracrine growth factor for GBM cells. These observations strongly support the concept that tumour angiogenesis is regulated by paracrine mechanisms and identify beside VEGF, AM as a potential tumour angiogenesis factor in vivo which constitutes a potential interesting molecular target in GBM treatment. 相似文献
17.
Nad S Marcinko D Vuksan-Aeusa B Jakovljević M Jakovljevic G 《The Journal of nervous and mental disease》2008,196(1):79-83
We investigated relationships between spiritual well-being (SWB), intrinsic religiosity (IR), and suicidal behavior in 45 Croatian war veterans with chronic posttraumatic stress disorder and 32 healthy volunteers. Compared with the volunteers, the veterans had significantly lower SWB scores (p = 0.000) and existential well-being (EWB) scores (p = 0.000). Scores on the religious well-being (RWB) subscale (p = 0.108) and the IR scale did not differ significantly between the groups (p = 0.803). Veterans' suicidality inversely correlated with SWB (p = 0.000), EWB (p = 0.000), RWB (p = 0.026), and IR (p = 0.041), with the association being stronger for the EWB subscale than for the RWB subscale. Veterans who had attempted suicide at least once in their lifetime had significantly higher Suicidal Assessment Scale scores and lower EWB scores than veterans who never attempted suicide. Low EWB scores may imply an increased risk of suicidality. Some religious activities were more frequent among the veterans than among the healthy volunteers, possibly reflecting the veterans' increased help-seeking behavior due to poor EWB. 相似文献
18.
JUN oncogene amplification and overexpression block adipocytic differentiation in highly aggressive sarcomas 总被引:1,自引:0,他引:1
Mariani O Brennetot C Coindre JM Gruel N Ganem C Delattre O Stern MH Aurias A 《Cancer cell》2007,11(4):361-374
The human oncogene JUN encodes a component of the AP-1 complex and is consequently involved in a wide range of pivotal cellular processes, including cell proliferation, transformation, and apoptosis. Nevertheless, despite extensive analyses of its functions, it has never been directly involved in a human cancer. We demonstrate here that it is highly amplified and overexpressed in undifferentiated and aggressive human sarcomas, which are blocked at an early step of adipocyte differentiation. We confirm by cellular and xenograft mouse models recapitulating these sarcoma genetics that the failure to differentiate is dependent upon JUN amplification/overexpression. 相似文献
19.
A significant association has been established, in clinical studies, between the expression or activity of thymidylate synthase (TYMS) and the efficiency of fluorouracil. TYMS expression is partly under the dependence of gene polymorphisms in the 5' and 3' untranslated regions (UTR), but conflicting results have been obtained about their roles on fluorouracil efficiency. In this study, we wanted to use the National Cancer Institute (NCI) panel of 60 human tumour cell lines to clarify this problem. Three relevant polymorphisms of the TYMS gene were studied: (i) the 5'UTR tandem repeat of 28-bp (2R/3R polymorphism); (ii) the single nucleotide polymorphism (SNP) within the second repeat (3C/3G polymorphism); (iii) the 3'UTR 6-bp deletion (+6/-6 polymorphism). Allele frequencies were close to those expected in a Caucasian population (2R/3C/3G: 53/29/18%; +6/-6: 68/32%), but the proportion of heterozygous genotypes was lower than expected from allele frequencies. The 2R and 3G alleles were significantly associated with the +6 and the -6 alleles, respectively. There was a significant association between the presence of the 3G allele and TYMS mRNA expression and catalytic activity, particularly in p53-mutated cell lines. However, no significant correlation existed between fluorouracil cytotoxicity, as extracted from the NCI databases, and TYMS expression, activity or polymorphisms. 相似文献
20.
Drosophila melanogaster flies were exposed to hypergravity starting at two days of age, the range of gravity levels used being 2.58–7.38 g. No longevity change was observed for exposures of less than 14 days. The longevity of males increased if they were submitted to hypergravity for durations ranging from 14 to 24 days. This increase in longevity was never observed in females. The positive effect of exposure to hypergravity has been replicated in two laboratories using two wild-type strains and different rearing conditions. A short hypergravity exposure seems to be a mild stress, yielding positive effects on longevity. This is in accordance with two previous studies showing a slight longevity increase after heat shock in the nematode Caenorhabditis elegans and in Drosophila melanogaster. 相似文献