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排序方式: 共有508条查询结果,搜索用时 17 毫秒
91.
Roberto Altieri Alessandro Esposito Francesca Parati Arianna Lobianco Milva Pepi 《International biodeterioration & biodegradation》2009,63(8):993-997
The feasibility of using olive mill waste (OMW) as an ingredient in the substrate used for cultivation of Agaricus bisporus (Lange) Sing. was studied in a large-scale cultivation trial, concerning 2500 m2 of mushroom growing area, at a specialized mushroom farm. Standard commercial cultivation technique involving compost preparation, spawning, casing and harvesting was used. The performance indicators such as mushroom yield, biological efficiency, market quality as well as horticultural value of the spent compost showed that the compost prepared with OMW was superior to the control compost in all the categories. The OMW-amended substrate supported higher populations of beneficial microorganisms especially, actinomycetes which enabled the breakdown of the compost ingredients. It is suggested that OMW is a suitable ingredient for the preparation of mushroom substrate. We have demonstrated that conversion of OMW (a liability) into value-added mushroom substrate (an asset) is an effective waste management tool in oleaculture. 相似文献
92.
Venkata Sabbisetti Arianna Di Napoli Apryle Seeley Angela M. Amato Esther O'Regan Musie Ghebremichael Massimo Loda Sabina Signoretti 《PloS one》2009,4(6)
There is increasing evidence that p63, and specifically ΔNp63, plays a central role in both development and tumorigenesis by promoting epithelial cell survival. However, few studies have addressed the molecular mechanisms through which such important function is exerted. Fatty acid synthase (FASN), a key enzyme that synthesizes long-chain fatty acids and is involved in both embryogenesis and cancer, has been recently proposed as a direct target of p53 family members, including p63 and p73. Here we show that knockdown of either total or ΔN-specific p63 isoforms in squamous cell carcinoma (SCC9) or immortalized prostate epithelial (iPrEC) cells caused a decrease in cell viability by inducing apoptosis without affecting the cell cycle. p63 silencing significantly reduced both the expression and the activity of FASN. Importantly, stable overexpression of either FASN or myristoylated AKT (myr-AKT) was able to partially rescue cells from cell death induced by p63 silencing. FASN induced AKT phosphorylation and a significant reduction in cell viability was observed when FASN-overexpressing SCC9 cells were treated with an AKT inhibitor after p63 knockdown, indicating that AKT plays a major role in FASN-mediated survival. Activated AKT did not cause any alteration in the FASN protein levels but induced its activity, suggesting that the rescue from apoptosis documented in the p63-silenced cells expressing myr-AKT cells may be partially mediated by FASN. Finally, we demonstrated that p63 and FASN expression are positively associated in clinical squamous cell carcinoma samples as well as in the developing prostate. Taken together, our findings demonstrate that FASN is a functionally relevant target of p63 and is required for mediating its pro-survival effects. 相似文献
93.
A herpes simplex virus recombinant that exhibits a single-chain antibody to HER2/neu enters cells through the mammary tumor receptor, independently of the gD receptors 下载免费PDF全文
The human epidermal growth factor receptor 2/neuregulin (HER2/neu) receptor is overexpressed in highly malignant mammary and ovarian tumors and correlates with a poor prognosis. It is a target for therapy; humanized monoclonal antibodies to HER2 have led to increased survival of patients with HER2/neu-positive breast cancer. As a first step in the design of an oncolytic herpes simplex virus able to selectively infect HER2/neu-positive cells, we constructed two recombinants, R-LM11 and R-LM11L, that carry a single-chain antibody (scFv) against HER2 inserted at residue 24 of gD. The inserts were 247 or 256 amino acids long, and the size of the gD ectodomain was almost doubled by the insertion. We report the following. R-LM11 and R-LM11L infected derivatives of receptor-negative J or CHO cells that expressed HER2/neu as the sole receptor. Entry was dependent on HER2/neu, since it was inhibited in a dose-dependent manner by monoclonal antibodies to HER2/neu and by a soluble form of the receptor. The scFv insertion in gD disrupted the ability of the virus to enter cells through HVEM but maintained the ability to enter through nectin1. This report provides proof of principle that gD can tolerate fusion to a heterologous protein almost as large as the gD ectodomain itself without loss of profusion activity. Because the number of scFv's to a variety of receptors is continually increasing, this report makes possible the specific targeting of herpes simplex virus to a large collection of cell surface molecules for both oncolytic activity and visualization of tumor cells. 相似文献
94.
Corallini F Celeghini C Rimondi E di Iasio MG Gonelli A Secchiero P Zauli G 《Journal of cellular physiology》2011,226(9):2279-2286
The soluble member of the TNF-R superfamily osteoprotegerin (OPG) is abundantly released under basal conditions by both mesenchymal stem cells (MSC) and fibroblasts and by endothelial cells upon stimulation with inflammatory cytokines. Since MSC, fibroblasts and endothelial cells represent key elements of the normal and tumor microenvironment and express detectable levels of surface TRAIL receptors, we investigated the effect of TRAIL on OPG release. Unexpectedly, recombinant TRAIL decreased the spontaneous OPG release in all cell types examined. Moreover, TRAIL decreased OPG release also in stromal cells co-cultured with lymphoma cells and counteracted the OPG induction by TN-alpha in HUVEC and MSC. Such down-regulation was not due to a masking effect in the ELISA quantification of the OPG released in the culture supernatants due to binding of OPG to its ligands (TRAIL and RANKL), as demonstrated by competition experiments with recombinant TRAIL and by the lack of RANKL release/induction. In addition, OPG down-regulation was not due to induction of cytotoxic effects by TRAIL, since the degree of apoptosis in response to TRAIL was negligible in all primary cell types. With regards to the possible molecular mechanism accounting for the down-regulation of OPG release by TRAIL, we found that treatment of MSC with TRAIL significantly decreased the phosphorylation levels of p38/MAPK. There is a suggestion that this pathway is involved in the stabilization of OPG mRNA. In this respect, the ability of TRAIL to decrease the release of OPG, in the absence of cell cytotoxicity, was mimicked by the p38/MAPK inhibitor SB203580. 相似文献
95.
Onesto E Rusmini P Crippa V Ferri N Zito A Galbiati M Poletti A 《Journal of neurochemistry》2011,118(2):266-280
Amyotrophic lateral sclerosis (ALS) is a fatal motoneuronal disease which occurs in sporadic or familial forms, clinically indistinguishable. About 15% of familial ALS cases are linked to mutations of the superoxide dismutase 1 (SOD1) gene that may induce misfolding in the coded protein, exerting neurotoxicity to motoneurons. However, other cell types might be target of SOD1 toxicity, because muscle-restricted expression of mutant SOD1 correlates with muscle atrophy and motoneurons death. We analysed the molecular behaviour of mutant SOD1 in motoneuronal NSC34 and muscle C2C12 cells. We found that misfolded mutant SOD1 clearance is much more efficient in muscle C2C12 than in motoneuronal NSC34 cells. Mutant SOD1 forms aggregates and impairs the proteasome only in motoneuronal NSC34 cells. Interestingly, NSC34 cells expressing mutant SOD1 are more sensitive to a superoxide-induced oxidative stress. Moreover, in muscle C2C12 cells mutant SOD1 remains soluble even when proteasome is inhibited with MG132. The higher mutant SOD1 clearance in muscle cells correlates with a more efficient proteasome activity, combined with a robust autophagy activation. Therefore, muscle cells seem to better manage misfolded SOD1 species, not because of an intrinsic property of the mutant protein, but in function of the cell environment, indicating also that the SOD1 toxicity at muscle level may not directly depend on its aggregation rate. 相似文献
96.
Chiral dehydroamino acid building blocks are versatile starting materials for the preparation of optically active unusual amino acids and other compounds of pharmacological interest. Herein we disclose the expedient preparation of dehydroalanines (ΔAla) equipped with oxazolidin-2-one (Oxd) chiral auxiliaries, Ts-Oxd-ΔAla-OMe. These compounds have been obtained in high yields from dipeptides Ts-Ser/Thr/phenylSer-Ser-OMe by the one-pot cyclization–elimination reaction with N,N-disuccinimidyl carbonate and catalytic DIPEA. To test the efficacy of the chiral auxiliaries in controlling asymmetric transformations, the Friedel–Crafts alkylations of indoles carrying diverse substituents were performed in the presence of Lewis and Brønsted acids. The reactions proceeded with good to excellent diastereomeric ratios giving (S)- or (R)-tryptophan derivatives, isolated very conveniently by simple flash chromatography. To verify the utility of this approach, optically pure (S)-2-methyltryptophan and (S)-5-fluorotryptophan were obtained and utilized to prepare analogues of endogenous opioid peptide endomorphin-1, H-Tyr-Pro-Trp-PheNH2. 相似文献
97.
Arianna Manunza Joaquim Casellas Raquel Quintanilla Rayner González-Prendes Ramona N Pena Joan Tibau Anna Mercadé Anna Castelló Nitdia Aznárez Jules Hernández-Sánchez Marcel Amills 《BMC genomics》2014,15(1)
Background
The genetic determinism of blood lipid concentrations, the main risk factor for atherosclerosis, is practically unknown in species other than human and mouse. Even in model organisms, little is known about how the genetic determinants of lipid traits are modulated by age-specific factors. To gain new insights into this issue, we have carried out a genome-wide association study (GWAS) for cholesterol (CHOL), triglyceride (TRIG) and low (LDL) and high (HDL) density lipoprotein concentrations measured in Duroc pigs at two time points (45 and 190 days).Results
Analysis of data with mixed-model methods (EMMAX, GEMMA, GenABEL) and PLINK showed a low positional concordance between trait-associated regions (TARs) for serum lipids at 45 and 190 days. Besides, the proportion of phenotypic variance explained by SNPs at these two time points was also substantially different. The four analyses consistently detected two regions on SSC3 (124 Mb, CHOL and LDL at 190 days) and SSC6 (135 Mb, CHOL and TRIG at 190 days) with highly significant effects on the porcine blood lipid profile. Moreover, we have found that SNP variation within SSC3, SSC6, SSC10, SSC13 and SSC16 TARs is associated with the expression of several genes mapping to other chromosomes and related to lipid metabolism.Conclusions
Our data demonstrate that the effects of genomic determinants influencing lipid concentrations in pigs, as well as the amount of phenotypic variance they explain, are influenced by age-related factors.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2164-15-758) contains supplementary material, which is available to authorized users. 相似文献98.
Arianna Scuteri Elisabetta Donzelli Virginia Rodriguez-Menendez Maddalena Ravasi Marianna Monfrini Barbara Bonandrini Marina Figliuzzi Andrea Remuzzi Giovanni Tredici 《PloS one》2014,9(1)
The clinical usability of pancreatic islet transplantation for the treatment of type I diabetes, despite some encouraging results, is currently hampered by the short lifespan of the transplanted tissue. In vivo studies have demonstrated that co-transplantation of Mesenchymal Stem Cells (MSCs) with transplanted pancreatic islets is more effective with respect to pancreatic islets alone in ensuring glycemia control in diabetic rats, but the molecular mechanisms of this action are still unclear.The aim of this study was to elucidate the molecular mechanisms of the positive effect of MSCs on pancreatic islet functionality by setting up direct, indirect and mixed co-cultures.MSCs were both able to prolong the survival of pancreatic islets, and to directly differentiate into an “insulin-releasing” phenotype. Two distinct mechanisms mediated these effects: i) the survival increase was observed in pancreatic islets indirectly co-cultured with MSCs, probably mediated by the trophic factors released by MSCs; ii) MSCs in direct contact with pancreatic islets started to express Pdx1, a pivotal gene of insulin production, and then differentiated into insulin releasing cells. These results demonstrate that MSCs may be useful for potentiating pancreatic islets'' functionality and feasibility. 相似文献
99.
Matthieu Legrand Benedetta De Berardinis Hanna K. Gaggin Laura Magrini Arianna Belcher Benedetta Zancla Alexandra Femia Mandy Simon Shweta Motiwala Rasika Sambhare Salvatore Di Somma Alexandre Mebazaa Vishal S. Vaidya James L. Januzzi Jr from the Global Research on Acute Conditions Team 《PloS one》2014,9(11)
Objective
The objective of the study was to assess urinary biomarkers of renal injury for their individual or collective ability to predict Worsening renal function (WRF) in patients with acutely decompensated heart failure (ADHF).Methods
In a prospective, blinded international study, 87 emergency department (ED) patients with ADHF were evaluated with biomarkers of cardiac stretch (B type natriuretic peptide [BNP] and its amino terminal equivalent [NT-proBNP], ST2), biomarkers of renal function (creatinine, estimated glomerular filtration rate [eGFR]) and biomarkers of renal injury (plasma neutrophil gelatinase associated lipocalin [pNGAL], urine kidney injury molecule-1 [KIM-1], urine N-acetyl-beta-D-glucosaminidase [NAG], urine Cystatin C, urine fibrinogen). The primary endpoint was WRF.Results
26% developed WRF; baseline characteristics of subjects who developed WRF were generally comparable to those who did not. Biomarkers of renal function and urine biomarkers of renal injury were not correlated, while urine biomarkers of renal injury correlated between each other. Biomarker concentrations were similar between patients with and without WRF except for baseline BNP. Although plasma NGAL was associated with the combined endpoint, none of the biomarker showed predictive accuracy for WRF.Conclusions
In ED patients with ADHF, urine biomarkers of renal injury did not predict WRF. Our data suggest that a weak association exists between renal dysfunction and renal injury in this setting (Clinicaltrials.gov NCT#0150153). 相似文献100.
Martin W. Bratschi Marie-Thérèse Ruf Arianna Andreoli Jacques C. Minyem Sarah Kerber Fidèle G. Wantong James Pritchard Victoria Chakwera Christian Beuret Matthias Wittwer Djeunga Noumen Nadia Schürch Alphonse Um Book Gerd Pluschke 《PLoS neglected tropical diseases》2014,8(3)
Buruli ulcer (BU), a neglected tropical disease of the skin and subcutaneous tissue, is caused by Mycobacterium ulcerans and is the third most common mycobacterial disease after tuberculosis and leprosy. While there is a strong association of the occurrence of the disease with stagnant or slow flowing water bodies, the exact mode of transmission of BU is not clear. M. ulcerans has emerged from the environmental fish pathogen M. marinum by acquisition of a virulence plasmid encoding the enzymes required for the production of the cytotoxic macrolide toxin mycolactone, which is a key factor in the pathogenesis of BU. Comparative genomic studies have further shown extensive pseudogene formation and downsizing of the M. ulcerans genome, indicative for an adaptation to a more stable ecological niche. This has raised the question whether this pathogen is still present in water-associated environmental reservoirs. Here we show persistence of M. ulcerans specific DNA sequences over a period of more than two years at a water contact location of BU patients in an endemic village of Cameroon. At defined positions in a shallow water hole used by the villagers for washing and bathing, detritus remained consistently positive for M. ulcerans DNA. The observed mean real-time PCR Ct difference of 1.45 between the insertion sequences IS2606 and IS2404 indicated that lineage 3 M. ulcerans, which cause human disease, persisted in this environment after successful treatment of all local patients. Underwater decaying organic matter may therefore represent a reservoir of M. ulcerans for direct infection of skin lesions or vector-associated transmission. 相似文献