The interactions of sodium diclofenac drug (s-DCF) with different graphene species were investigated using both first principles calculations based on Density Functional Theory (DFT) and adsorption ...experiments. Through batch adsorption experiments, it was found that rGO was a good adsorbent for removing the s-DCF drug from aqueous solutions. The general-order kinetic model shows the best fit to the experimental data compared with pseudo-first order and pseudo-second order kinetic adsorption models. The equilibrium data (at 25 °C) were fitted to the Liu isotherm model. The maximum sorption capacity for adsorption of the s-DCF drug was 59.67 mg g(-1) for rGO. The s-DCF adsorption onto pristine graphene, graphene with a vacancy, reduced oxide graphene (rGO) and functionalized graphene nanoribbons were simulated providing a good understanding of the adsorption process of this molecule on graphene-family surfaces. The results predict a physisorption regime in all cases. Based on these results, the ab initio calculations and the adsorption experiments point out that the graphene-family are promising materials for extracting s-DCF from wastewater effluents.
•Five B. cinerea laccases were identified in sweet white wines.•A LC–MS/MRM method targeting laccase-2-BcLCC2 and laccase-3-BcLCC7 was developed.•Laccase-2-BcLCC2 and laccase-3-BcLCC7 were in higher ...amount in botrytized wines.
Botrytized sweet wines are made with berries infected by the fungus Botrytis cinerea. The aim of this study was to identify biomarkers of B. cinerea infection in sweet wines with a focus on laccases which are exocellular oxidase enzymes produced by this fungus during fruit contamination. Total proteins from six commercial sweet wines, including three naturally botrytized wines and three non-botrytized wines were analysed by LC-QTOF-MS. Five laccases, namely laccase-1-BcLCC1, laccase-2-BcLCC2, laccase-3-BcLCC7, laccase-8-BcLCC8 and laccase-12-BcLCC12, were identified in both types of wine. Then, a targeted proteomic approach by LC-MRM was used to semi-quantify laccase-2-BcLCC2 and laccase-3-BcLCC7, in the six samples. LC-MRM targeted analysis of the two enzymes allowed the discrimination of botrytized versus non-botrytized sweet white wines.
Suppressor of cytokine signaling 1 (SOCS1) is considered as a tumor suppressor protein in hepatocellular carcinoma (HCC), but the underlying mechanisms remain unclear. Previously, we have shown that ...SOCS1-deficient hepatocytes displayed increased responsiveness to hepatocyte growth factor (HGF) due to enhanced signaling via the MET receptor tyrosine kinase. As aberrant MET activation occurs in many tumors including HCC, here we elucidated the mechanisms of SOCS1-mediated regulation. SOCS1 attenuated HGF-induced proliferation of human and mouse HCC cell lines and their growth as tumors in NOD.scid.gamma mice. Tumors formed by SOCS1 expressing HCC cells showed significantly reduced MET expression, indicating that SOCS1 not only attenuates MET signaling but also regulates MET expression. Mechanistically, SOCS1 interacted with MET via the Src homology 2 domain and this interaction was promoted by MET tyrosine kinase activity. The SOCS1-mediated reduction in MET expression does not require the juxtamembrane Y1003 residue implicated in Cbl-mediated downmodulation. Moreover, the proteasome inhibitor MG-132, but not the inhibitors of lysosomal degradation bafilomycin and chloroquine, reversed the SOCS1-mediated reduction in MET expression, indicating that this process is distinct from Cbl-mediated downmodulation. Accordingly, SOCS1 promoted polyubiquitination of MET via K48-dependent but not K63-mediated ubiquitin chain elongation. Furthermore, siRNA-mediated downmodulation of Cbl did not abolish SOCS1-mediated reduction in MET expression in HCC cells. SOCS1-dependent ubiquitination of endogenous MET receptor occurred rapidly following HGF stimulation in HCC cells, leading to proteasomal degradation of phosphorylated MET receptor. These findings indicate that SOCS1 mediates its tumor suppressor functions, at least partly, by binding to MET and interfering with downstream signaling pathways as well as by promoting the turnover of the activated MET receptor. We propose that loss of this control mechanism due to epigenetic repression of SOCS1 could contribute to oncogenic MET signaling in HCC and other cancers, and that MET inhibitors might be useful in treating these patients.
In most patients with breast cancer, radiotherapy induces inflammation that is characterised by an increase of promigratory factors in healthy tissues surrounding the tumour. However, their role in ...the emergence of the migration phenotype and formation of metastases is still unclear.
A single mammary gland of BALB/c mice was irradiated with four doses of 6 Gy given at a 24-h interval. After the last session of irradiation, treated and control mammary glands were either collected for quantification of promigratory and proinflammatory factors or were implanted with fluorescent ubiquitination-based cell cycle indicator (FUCCI)-expressing mouse mammary cancer D2A1 cells. The migration of cancer cells in the mammary glands was monitored by optical imaging. On day 21, mammary tumours and lungs were collected for histology analyses and the quantification of metastases.
Pre-irradiation of the mammary gland increased by 1.8-fold the migration of cancer cells, by 2-fold the quantity of circulating cancer cells and by 2.4-fold the number of lung metastases. These adverse effects were associated with the induction of interleukin-6 (IL-6) and cyclooxygenase-2 (COX-2).
The emergence of the metastasis phenotype is believed to be associated with the accumulation of mutations in cancer cells. Our results suggest an alternative mechanism based on promigratory factors from irradiated mammary glands. In clinic, the efficiency of radiotherapy could be improved by anti-inflammatory agents that would prevent the stimulation of cancer cell migration induced by radiation.
Les polyphénols du raisin Chira, K.; Suh, J. -H.; Saucier, C. ...
Phytothérapie (Paris, France),
2008/4, Volume:
6, Issue:
2
Journal Article
Peer reviewed
Résumé
Le raisin possède une spécificité par les composés phénoliques antioxydants qu’il renferme (flavonoïdes et non-flavonoïdes). Les structures et principales familles de composés phénoliques du ...raisin sont données. La consommation modérée de raisin ou de produits dérivés (contenant des polyphénols) peut conduire à une diminution de l’agrégation plaquettaire ainsi qu’à des effets vasodilatateurs des vaisseaux sanguins. Les effets physiologiques obtenus pour la consommation nutritionnelle d’extrait de polyphénols de raisin sur l’athérosclérose, le diabète ou l’hypertension montrent une prévention
in vivo
de ces pathologies pour les modèles étudiés avec une synergie lorsque éthanol et polyphénols sont associés, par l’intermédiaire de plusieurs mécanismes. Les polyphénols du raisin peuvent donc jouer un rôle de nutrition préventive.
Background and Aims
Laccase enzymes produced by Botrytis cinerea are involved in the oxidation of phenolic substances during the development of grey mould, which causes significant economic losses. ...The aim of this work was to study the structural and activity characteristics of the laccase enzymes secreted by three B. cinerea strains that are involved in the development of grey mould.
Methods and Results
Laccase enzymes obtained from three B. cinerea strains one reference strain (B05.10) and two strains obtained from two French vineyards (VA612 and RM344) were characterised. Analysis by LC‐QTOF‐MS revealed that the three strains contained a mixture of Laccase‐2‐BcLCC2 and Laccase‐3‐BcLCC7. The structural characteristics of the laccases from the three strains, such as molecular weight and glycosylation degree, were identical. Nevertheless, their catalytic activities were significantly different.
Conclusions
Differences in catalytic activities could be due either to possible differences in the relative amount of Laccase‐2‐BcLCC2 and Laccase‐3‐BcLCC7 produced by each strain or to differences in the glycosidic fraction of the enzymes.
Significance of the Study
The severity of the infection caused by B. cinerea may be not only related to the infection level but also to the strain involved.
The conversion of seed oil based feedstocks such as methyl oleate into useful commercial raw materials via olefin metathesis has been a research focus for decades, due to their low cost and renewable ...supply, but technical success has been limited due to poor catalyst activities and turnovers. We report here recent studies on the cross-metathesis of methyl oleate with ethylene (ethenolysis) catalyzed by bis(tricyclohexylphosphine)benzylideneruthenium dichloride (1). At 25 °C/60 psig of ethylene, catalysis by 1 results in the highly selective formation of 1-decene and methyl 9-decenoate. However, reactivity losses limit the catalyst turnovers well below commercial viability in batch reactor operation. In an attempt to address the limitations of this chemistry, a combination of an experimental evaluation of the impact of process parameters, a detailed analysis of the fundamental reaction steps, kinetic modeling, and molecular modeling has been applied to develop a more detailed understanding of this complex catalytic pathway. These fundamental studies have led to a more complete understanding of the factors impacting catalyst performance and the identification of approaches necessary to achieve an economically viable process.
The suppressor of cytokine signaling 1 (SOCS1) gene is repressed in prostate cancer (PCa) by epigenetic silencing and microRNA miR30d. Increased expression of the SOCS1-targeting miR30d correlates ...with higher biochemical recurrence, suggesting a tumor suppressor role of SOCS1 in PCa, but the underlying mechanisms are unclear. We have shown that SOCS1 inhibits MET receptor kinase signaling, a key oncogenic pathway in cancer progression. Here we evaluated the role of SOCS1 in attenuating MET signaling in PCa cells and tumor growth in vivo.
MET-overexpressing human DU145 and PC3 PCa cell lines were stably transduced with SOCS1, and their growth, migration and invasion of collagen matrix were evaluated in vitro. Cells expressing SOCS1 or the control vector were evaluated for tumor growth in NOD.scid.gamma mice as xenograft or orthotopic tumors.
HGF-induced MET signaling was attenuated in SOCS1-expressing DU145 and PC3 cells. Compared with vector control cells, SOCS1-expressing cells showed reduced proliferation and impaired migration following HGF stimulation. DU145 and PC3 cells showed marked ability to invade the collagen matrix following HGF stimulation and this was attenuated by SOCS1. As xenografts, SOCS1-expressing PCa cells showed significantly reduced tumor growth compared with vector control cells. In the orthotopic tumor model, SOCS1 reduced the growth of primary tumors and metastatic spread. Intriguingly, the SOCS1-expressing DU145 and PC3 tumors showed increased collagen deposition, associated with increased frequency of myofibroblasts.
Our findings support the tumor suppressor role of SOCS1 in PCa and suggest that attenuation of MET signaling is one of the underlying mechanisms. SOCS1 in PCa cells also appears to prevent the tumor-promoting functions of cancer-associated fibroblasts.
Cell walls were isolated from seeds of grape berries (Vitis vinifera L.), and proanthocyanidin composition was determined over the course of ripening for different levels of vine water status. During ...the ripening period the tannins from the cell walls were always more polymerized than those from the inner part of the cell. At maturity this difference becomes more significant compared to véraison, due to a significant increase in the mean degree of polymerization of the cell wall tannins. The tannin composition was typical of grape seed tannins and was quite similar in the two cell fractions studied, but the epicatechin gallate proportion was significantly higher in the cell wall fraction. There were no significant effects of water deficit on composition and polymerization of seed tannins. Keywords: Vitis vinifera L.; grape seeds; cell wall; tannins; water status
The antioxidant synergy between (+)-catechin and other wine or biological antioxidants (Trolox, ascorbate, SO2, uric acid) was measured in vitro using the Folin−Ciocalteu (FC) and metmyoglobin ...assays. Although the two assays are based on very different reagents (i.e., metal salts versus organic and biochemical reagents), the individual antioxidants showed similar relative activities in both systems. In addition, interaction studies showed simple additive effects in all cases except with the (+)-catechin/SO2 mixture, which showed a remarkable synergetic effect in both assays. Keywords: Antioxidant; interaction; synergy; wine; free radical; catechin; SO2; ascorbic acid
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