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11.

Background

Obesity is widely recognised as an important risk factor for colorectal cancer (CC).

Aim

The study aimed to evaluate the effect of CC on circulating concentrations and gene expression levels of inflammatory and angiogenesis-related factors in human visceral adipose tissue (VAT).

Methods

VAT biopsies were obtained from 18 healthy individuals and 11 patients with CC. Real-time polymerase chain reactions were performed to quantify gene expression levels and zymographic analyses were used to determine the activity of matrix metalloproteinases (MMPs).

Results

Patients with CC exhibited increased mRNA expression levels of lipocalin-2 (P=.014), osteopontin (P=.027), tumor necrosis factor-α (TNF-α) (P=.016) and chitinase-3 like-1 (P=.006) compared to control subjects in VAT. Gene expression levels of hypoxia-inducible factor-1 α, vascular endothelial growth factor and MMP-2 were significantly higher (P<.05) in VAT of patients with CC. The expression of insulin-like growth factor I, insulin growth factor binding protein 3 and MMP-9 followed the same trend, although no significant differences were reached. The enzymatic activity of MMP-9 was increased (P<.001) in patients with CC. Furthermore, individuals with CC showed increased (P<.05) circulating concentrations of the inflammatory markers interleukin-6, tumour necrosis factor α and hepatocyte growth factor, whereas levels of the anti-inflammatory adipokine adiponectin were decreased (P<.01).

Conclusion

These findings represent the first observation that mRNA levels of the novel inflammatory factors lipocalin-2, chitinase-3 like-1 and osteopontin are increased in human VAT of subjects with CC. This observation together with the up-regulation of angiogenic factors suggests that adipokines secreted by VAT may be involved in the development of colon cancer.  相似文献   
12.
Recent studies have shown aberrant expression of SOX11 in various types of aggressive B-cell neoplasms. To elucidate the molecular mechanisms leading to such deregulation, we performed a comprehensive SOX11 gene expression and epigenetic study in stem cells, normal hematopoietic cells and different lymphoid neoplasms. We observed that SOX11 expression is associated with unmethylated DNA and presence of activating histone marks (H3K9/14Ac and H3K4me3) in embryonic stem cells and some aggressive B-cell neoplasms. In contrast, adult stem cells, normal hematopoietic cells and other lymphoid neoplasms do not express SOX11. Such repression was associated with silencing histone marks H3K9me2 and H3K27me3. The SOX11 promoter of non-malignant cells was consistently unmethylated whereas lymphoid neoplasms with silenced SOX11 tended to acquire DNA hypermethylation. SOX11 silencing in cell lines was reversed by the histone deacetylase inhibitor SAHA but not by the DNA methyltransferase inhibitor AZA. These data indicate that, although DNA hypermethylation of SOX11 is frequent in lymphoid neoplasms, it seems to be functionally inert, as SOX11 is already silenced in the hematopoietic system. In contrast, the pathogenic role of SOX11 is associated with its de novo expression in some aggressive lymphoid malignancies, which is mediated by a shift from inactivating to activating histone modifications.  相似文献   
13.
In an attempt to improve the detection of peroxisome proliferation as a biomarker in environmental pollution assessment, we have applied a novel approach based on peroxisomal proteomics. Peroxisomal proteins from digestive glands of mussels Mytilus galloprovincialis were analyzed using 2-DE and MS. We have generated a reference 2-DE map from samples obtained in a well-studied reference area and compared this with peroxisomal proteomes from other sequenced genomes. In addition, by comparing 2-DE maps from control samples with samples obtained in a polluted area, we have characterized the peroxisome proliferation expression pattern associated with exposure to a polluted environment. Over 100 spots were reproducibly resolved per 2-DE map; 55 differentially expressed spots were quantitatively detected and analyzed, and 14 of these showed an increase in protein expression of more than fourfold. Epoxide hydrolase, peroxisomal antioxidant enzyme, and sarcosine oxidase (SOX) have been identified by ESI MS/MS, and acyl-CoA oxidase, multifunctional protein, and Cu,Zn-superoxide dismutase were immunolocalized by Western blotting. Our results indicate that a peroxisomal protein pattern associated to marine pollutant exposure can be generated, and this approach may have a greater potential as biomarker than traditional, single-protein markers.  相似文献   
14.
A new vanadyl complex with the formula VO(L1)2, where L1=3-amino-6(7)-chloroquinoxaline-2-carbonitrile N(1), N(4)-dioxide, has been synthesized and characterized by elemental analyses, conductometry, fast atom bombardment mass spectroscopy (FAB-MS) and electronic, Fourier transform infrared (FTIR), Raman, nuclear magnetic resonance (NMR) and electron paramagnetic resonance (EPR) spectroscopies. Results were compared with those previously reported for analogous vanadium complexes with other 3-aminoquinoxaline-2-carbonitrile N1,N4-dioxide derivatives as ligands. As an effort to develop novel metal-based selective hypoxia-cytotoxins and to improve bioavailability and pharmacological and toxicological properties of aminoquinoxaline carbonitrile N-dioxides bioreductive prodrugs, the new complex and VO(L)2 complexes, with L=3-amino-6(7)-bromoquinoxaline-2-carbonitrile N1,N4-dioxide (L2) and 3-amino-6(7)-methylquinoxaline-2-carbonitrile N1,N4-dioxide (L3), were subjected to cytotoxic evaluation in V79 cells in hypoxic and aerobic conditions. The complexes resulted in vitro more potent cytotoxins than the free ligands (i.e. potencies P(VO(L1)2)=3.0, P(L1)=9.0 microM) and Tirapazamine (P=30.0 microM) and showed excellent selective cytotoxicity in hypoxia, being no cytotoxic in oxia. In addition, the solubility in hydrophilic solvents resulted significantly higher for the vanadyl complexes than for the free ligands. These results could be indicative that complexation of the quinoxaline-2-carbonitrile N1,N4-dioxide derivatives with vanadium could improve their bioavailability. In addition, a new aspect of the series has been investigated. A detailed comparison of the electrochemical behavior of the free ligands and the complexes has been performed searching for a correlation between reduction potentials of the complexes and their activities and hypoxia selectivities.  相似文献   
15.
Aquaporins are channels that allow the movement of water across the cell membrane. Some members of the aquaporin family, the aquaglyceroporins, also allow the transport of glycerol, which is involved in the biosynthesis of triglycerides and the maintenance of fasting glucose levels. Aquaporin-7 (AQP7) is a glycerol channel mainly expressed in adipocytes. The deletion of AQP7 gene in mice leads to obesity and type 2 diabetes. AQP7 modulates adipocyte glycerol permeability thereby controlling triglyceride accumulation and fat cell size. Furthermore, the coordinated regulation of fat-specific AQP7 and liver-specific AQP9 may be key to determine glucose metabolism in insulin resistance.  相似文献   
16.
The future environment may be altered by high concentrations of salt in the soil and elevated [CO2] in the atmosphere. These have opposite effects on photosynthesis. Generally, salt stress inhibits photosynthesis by stomatal and non-stomatal mechanisms; in contrast, elevated [CO2] stimulates photosynthesis by increasing CO2 availability in the Rubisco carboxylating site and by reducing photorespiration. However, few studies have focused on the interactive effects of these factors on photosynthesis. To elucidate this knowledge gap, we grew the barley plant, Hordeum vulgare (cv. Iranis), with and without salt stress at either ambient or elevated atmospheric [CO2] (350 or 700 μmol mol−1 CO2, respectively). We measured growth, several photosynthetic and fluorescence parameters, and carbohydrate content. Under saline conditions, the photosynthetic rate decreased, mostly because of stomatal limitations. Increasing salinity progressively increased metabolic (photochemical and biochemical) limitation; this included an increase in non-photochemical quenching and a reduction in the PSII quantum yield. When salinity was combined with elevated CO2, the rate of CO2 diffusion to the carboxylating site increased, despite lower stomatal and internal conductance. The greater CO2 availability increased the electron sink capacity, which alleviated the salt-induced metabolic limitations on the photosynthetic rate. Consequently, elevated CO2 partially mitigated the saline effects on photosynthesis by maintaining favorable biochemistry and photochemistry in barley leaves.  相似文献   
17.
Impairment of carbon metabolism induced by the herbicide glyphosate   总被引:1,自引:0,他引:1  
The herbicide glyphosate reduces plant growth and causes plant death by inhibiting the biosynthesis of aromatic amino acids. The objective of this work was to determine whether glyphosate-treated plants show a carbon metabolism pattern comparable to that of plants treated with herbicides that inhibit branched-chain amino acid biosynthesis. Glyphosate-treated plants showed impaired carbon metabolism with an accumulation of carbohydrates in the leaves and roots. The growth inhibition detected after glyphosate treatment suggested impaired metabolism that impedes the utilization of available carbohydrates or energy at the expected rate. These effects were common to both types of amino acid biosynthesis inhibitors. Under aerobic conditions, ethanolic fermentative metabolism was enhanced in the roots of glyphosate-treated plants. This fermentative response was not related to changes in the respiratory rate or to a limitation of the energy charge. This response, which was similar for both types of herbicides, might be considered a general response to stress conditions.  相似文献   
18.
Attention-deficit/hyperactivity disorder (ADHD) is associated with considerable impairment in health-related quality of life (HR-QoL). Atomoxetine has been found to improve HR-QoL in both children and adolescents. However, there is scarcity of data on gender differences in treatment responses to ADHD medications. This pooled analysis of five atomoxetine trials aimed to evaluate treatment differences with respect to HR-QoL and ADHD symptoms across genders. Data from 5 clinical atomoxetine trials (4 from Europe and 1 from Canada) with similar inclusion and exclusion criteria and similar durations (8- to 12-week follow-up) were included in the pooled analysis. All studies included the Child Health and Illness Profile-Child Edition (CHIP-CE) Parent Report Form. In addition, correlations between HR-QoL and ADHD core symptoms were compared between girls and boys. Data from 136 girls and 658 boys (mean age: 9.6 and 9.7 years, respectively) were pooled. Boys and girls were similarly impaired at baseline with minor differences in some of the subdomains. Treatment effect of atomoxetine was significant in both groups for the Risk Avoidance domain and its subdomains. No gender effect with both clinical and statistical significance was found for treatment outcome. Correlations between ADHD Rating Scale and CHIP-CE scores were similar in both genders and were generally low at baseline and moderate at endpoint and for the change from baseline to endpoint. Atomoxetine was effective in improving some aspects of HR-QoL in both genders without any significant differences across genders. Correlations between core symptoms of ADHD and HR-QoL were low to moderate in both boys and girls.  相似文献   
19.
The Early Pre-Pottery Neolithic B (EPPNB) in southwest Asia is a fundamental period in research on the origins of domesticated plants. However, there are few archaeobotanical data with which to characterise the plant-based subsistence and crop husbandry activities during this time, which hinders the understanding of the factors that triggered the appearance of plant domestication. In this paper, analyses of non-woody plant macro-remains provide new insights into subsistence activities such as crop cultivation (husbandry activities and storage) and plant use (wild plant gathering and food preparation) during the EPPNB at Tell Qarassa North (south Syria). We make comparisons between Tell Qarassa North and the evidence at earlier and later periods as to how plants were used, and highlight similarities and differences in the practices attested, as well as describing some of the consequences that these plant-related activities may have had in terms of labour and social organization during EPPNB.  相似文献   
20.
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