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41.

Background

Non-invasive early detection of lung cancer could reduce the number of patients diagnosed with advanced disease, which is associated with a poor prognosis. We analyzed the diagnostic accuracy of a panel of peripheral blood markers in detecting non small cell lung cancer (NSCLC).

Methods

100 healthy donors and 100 patients with NSCLC were enrolled onto this study. Free circulating DNA, circulating mRNA expression of peptidylarginine deiminase type 4 (PAD4/PADI4), pro-platelet basic protein (PPBP) and haptoglobin were evaluated using a Real-Time PCR-based method.

Results

Free circulating DNA, PADI4, PPBP and haptoglobin levels were significantly higher in NSCLC patients than in healthy donors (p<0.0001, p<0.0001, p = 0.0002 and p = 0.0001, respectively). The fitted logistic regression model demonstrated a significant direct association between marker expression and lung cancer risk. The odds ratios of individual markers were 6.93 (95% CI 4.15–11.58; p<0.0001) for free DNA, 6.99 (95% CI 3.75–13.03; p<0.0001) for PADI4, 2.85 (95% CI 1.71–4.75; p<0.0001) for PPBP and 1.16 (95% CI 1.01–1.33; p = 0.031) for haptoglobin. Free DNA in combination with PPBP and PADI4 gave an area under the ROC curve of 0.93, 95% CI = 0.90–0.97, with sensitivity and specificity over 90%.

Conclusions

Free circulating DNA analysis combined with PPBP and PADI4 expression determination appears to accurately discriminate between healthy donors and NSCLC patients. This non-invasive multimarker approach warrants further research to assess its potential role in the diagnostic or screening workup of subjects with suspected lung cancer.  相似文献   
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The rat ErbB2 (rErbB2) protein is a 185‐kDa glycoprotein belonging to the epidermal growth factor‐related proteins (ErbB) of receptor tyrosine kinases. Overexpression and mutations of ErbB proteins lead to several malignancies including breast, lung, pancreatic, bladder and ovary carcinomas. ErbB2 is immunogenic and is an ideal candidate for cancer immunotherapy. We investigated the possibility of expressing the extracellular (EC) domain of rErbB2 (653 amino acids, aa) in Nicotiana benthamiana plants, testing the influence of the 23 aa transmembrane (TM) sequence on protein accumulation. Synthetic variants of the rErbB2 gene portion encoding the EC domain, optimized with a human codon usage and either linked to the full TM domain (rErbB2_TM, 676 aa), to a portion of it (rErbB2‐pTM, 662 aa), or deprived of it (rErbB2_noTM, 653 aa) were cloned in the pEAQ‐HT expression vector as 6X His tag fusions. All rErbB2 variants (72–74.5 kDa) were transiently expressed, but the TM was detrimental for rErbB2 EC accumulation. rERbB2_noTM was the most expressed protein; it was solubilized and purified with Nickel affinity resin. When crude soluble extracts expressing rErbB2_noTM were administered to BALB/c mice, specific rErbB2 immune responses were triggered. A potent antitumour activity was induced when vaccinated mice were challenged with syngeneic transplantable ErbB2+ mammary carcinoma cells. To our knowledge, this is the first report of expression of rErbB2 in plants and of its efficacy in inducing a protective antitumour immune response, opening interesting perspectives for further immunological testing.  相似文献   
46.

Introduction

Essential oils are known to possess antimicrobial activity; thus, their use has played an important role over the years in medicine and for food preservation purposes.

Objective

The effect of clove oil and its major constituents as bactericidal agents on the global metabolic profiling of E. coli bacteria was assessed by means of metabolic alterations, using solid phase microextraction (SPME) as a sample preparation method coupled to complementary analytical platforms.

Method

E. Coli cultures treated with clove oil and its major individual components were sampled by HS-SPME-GCxGC-ToF/MS and SPME-UPLC–MS. Full factorial design was applied in order to estimate the most effective antibacterial agent towards E. coli. Central composite design and factorial design were applied to investigate parameters influencing metabolite coverage and efficiency by SPME.

Results

The metabolic profile, including 500 metabolites identified by LC–MS and 789 components detected by GCxGC-ToF/MS, 125 of which were identified as dysregulated metabolites, revealed changes in the metabolome provoked by the antibacterial activity of clove oil, and in particular its major constituent eugenol. Analyses of individual components selected using orthogonal projections to latent structures discriminant analysis showed a neat differentiation between control samples in comparison to treated samples in various sets of metabolic pathways.

Conclusions

The combination of a sample preparation method capable of providing cleaner extracts coupled to different analytical platforms was successful in uncovering changes in metabolic pathways associated with lipids biodegradation, changes in the TCA cycle, amino acids, and enzyme inhibitors in response to antibacterial treatment.
  相似文献   
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This study aimed to characterize the phenolic and the volatile constituents and to establish the antioxidant potential and the toxicity of a hydroalcoholic extract obtained from the leaves and flower buds of Matthiola incana (L.) R.Br. subsp. incana growing wild in Sicily (Italy). By HPLC‐PDA/ESI‐MS analysis, 12 phenolics (two phenolic acid derivatives and ten flavonoids) were identified, and eight of them were reported for the first time; luteolin‐glucoside was the main component (57.07 mg/g±0.87 % RSD). By SPME‐GC/MS, 47 volatile constituents were fully characterized, and dimethyl trisulfide turned out to be the most abundant one (33.24 %). The extract showed moderate activity both in the DPPH and in the reducing power assays (IC50=2.32±0.24 mg/mL; ASE/mL=12.29±0.42); it did not inhibit the lipid peroxidation, whereas it was found to possess good chelating properties reaching approximately 90 % activity at the highest tested dose. Moreover, the extract protected growth and survival from H2O2‐induced oxidative stress in Escherichia coli. Finally, the extract was non‐toxic against Artemia salina (LC50>1000 μg/mL). These findings increase the knowledge of M. incana subsp. incana and they could be helpful to a chemosystematic distinguishing of this subspecies also demonstrating that the aerial parts represent a safe source of antioxidants.  相似文献   
49.
Drosophila G9a is a nonessential gene   总被引:1,自引:1,他引:0  
Seum C  Bontron S  Reo E  Delattre M  Spierer P 《Genetics》2007,177(3):1955-1957
Mammalian G9a is a euchromatic histone H3 lysine 9 (H3K9) methyltransferase essential for development. Here, we characterize the Drosophila homolog of G9a, dG9a. We generated a dG9a deletion allele by homologous recombination. Analysis of this allele revealed that, in contrast to recent findings, dG9a is not required for fly viability.  相似文献   
50.
A sensitive, precise and accurate method for the quantification of the alimentary opioid peptide Gluten Exorphin B5 (GE-B5, Tyr-Gly-Gly-Trp-Leu) in cerebrospinal fluid (CSF) was developed using liquid chromatography-mass spectrometry (LC-MS). Aliquots (10 microL) of sheep CSF were injected into a LC-MS instrument equipped with a reversed-phase C12 column at a flow rate of 250 microL/min. The mobile phase consisted of Eluent A water with 0.01% acetic acid as an ion-pairing reagent, and Eluent B acetonitrile. The LC-MS system was programmed to divert column flow to waste for 3.5 min after injection, after which time flow was directed into the mass spectrometer that operated in positive ion mode. DADLE (Tyr-D-Ala-Gly-Phe-D-Leu) was used as Internal Standard. No significant interfering peaks were detected at the retention times of GE-B5 in CSF blanks. The calibration curves were linear in the range of 0.39-78.00 ng/mL. The lower limit of detection and the lower limit of quantitation values for GE-B5 in CSF were established at 0.30 and 0.78 ng/mL, respectively. The intra-day and inter-day precision values were <12% relative standard deviation. The intra-day and inter-day accuracy were 99.46-100.86% and 98.95-100.02%, respectively. Recovery of GE-B5 in CSF samples was greater than 80%. Stability studies indicate that GE-B5 in CSF undergoes significant degradation (>55% after 600 min), which is reduced by the addition of protease inhibitors. This is the first reported method for the quantification of GE-B5 in CSF.  相似文献   
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