ALBERT

Description: Similar to phosphorylation, transient conjugation of ubiquitin to target proteins (ubiquitination) mediated by the concerted action of ubiquitin ligases and de-ubiquitinating enzymes (DUBs) can affect substrate function. As obligate intracellular parasites, viruses rely on different cellular pathways for their own replication and the well conserved ubiquitin conjugating/de-conjugating system is not an exception. Viruses not only usurp the host proteins involved in the ubiquitination/de-ubiquitination process, but they also encode their own ubiquitin ligases and DUBs. Here we report that an N-terminal variant of the herpes simplex virus (HSV) type-1 large tegument protein VP1/2 (VP1/2 1–767 ), encompassing an active DUB domain (herpesvirus tegument ubiquitin specific protease, htUSP), and TSG101, a component of the endosomal sorting complex required for transport (ESCRT)-I, functionally interact. In particular, VP1/2 1–767 modulates TSG101 ubiquitination and influences its intracellular distribution. Given the role played by the ESCRT machinery in crucial steps of both cellular pathways and viral life cycle, the identification of TSG101 as a cellular target for the HSV-1 specific de-ubiquitinating enzyme contributes to the clarification of the still under debate function of viral encoded DUBs highly conserved throughout the Herpesviridae family. This article is protected by copyright. All rights reserved

Description: The transition to a pathological phenotype such as Barrett's esophagus occurs via induction of resistance upon repeated contact with gastric refluxate in esophagus. This study examined the molecular changes within normal esophageal epithelial cells (EECs) under short-term acid loading and the role of these changes in defensive resistance against acidic cytotoxicity. After primary cultured EECs were exposed to pH 4-acidified medium (AM4), cell viability was determined by the MTT assay. Reactive oxygen species (ROS) and NAD(P)H oxidase (NOX) activity were measured. Activation of the mitogen-activated protein kinases (MAPKs) MEK/ERK1/2, p38 and JNK; phosphoinositol-3-kinase (PI3K)/Akt, and nuclear factor-kappa B (NF-κB) were detected by Western blot analysis or immunofluorescence staining. AM4 incubation induced intracellular ROS generation accompanied by increase in NOX activity, which was further increased by Na + /H + exchange-1 (NHE1)-dependent inhibition but was prevented by inhibition of NOX or mitochondria complex I. AM4 also induced phosphorylation of MEK/ERK1/2, p38 MAPK, PI3K/Akt, and nuclear translocation of NF-κB, and all these effects, except for p38 MAPK phosphorylation, were abolished by inhibition of ROS. ROS-dependent PI3K/Akt activation, which mediates NF-κB nuclear translocation, was inhibited by protein tyrosine kinase (PTK) inhibitors and NHE1-specific inhibitor. All inhibitors of NHE, ROS, PTK, PI3K or NF-κB further decreased AM4-induced cell viability. Acid loading in the presence of NHE1-dependent protection induced ROS generation by activating NOX and mitochondria complex I, which stimulated PTK/PI3K/Akt/NF-κB-dependent survival in EEC. Our data indicate that normal EEC initially respond to acid loading through intrinsic survival activation. This article is protected by copyright. All rights reserved

Description: New 3-(hydroxyphenylphosphinyl)-propanoic acid (3-HPP) esters of cellulose were synthesized in N, N-dimethylacetamide/LiCl homogeneously by the method of in situ activation with p-toluenesulfonyl chloride. Chemical structure and thermal properties of the cellulose esters were investigated by FTIR, 13 C-NMR, TGA, RT-IR and Py–GC/MS, and their flame retardancy was studied by limiting oxygen index (LOI) test and vertical flammability test. It was found that the degree of substitution (DS) of cellulose esters, in the range from 0.62 to 1.42, had an obvious effect on solubility of cellulose esters. According to the FT-IR and Py–GC/MS results, flame retardant 3-HPP reacting with cellulose could accelerate dehydration action and decrease flammable released products. Besides, ESEM observation also confirmed that flame retardant cellulose (FRC) fibers with 3 wt% cellulose acetate prepared by dry-wet spinning technique possessed good flame resistance.

Description: In this study cotton fabric was coated with 5,5-dimethylhydantoin (DMH), followed by chlorination with sodium hypochlorite to impart antimicrobial properties and functions. An orthogonal array testing strategy was employed for obtaining the optimum treatment condition. After coating and chlorination, cotton fabrics were characterized with different methods. Ultraviolet spectroscopy, Scanning Electron Microscope and Fourier Transform Infrared Spectroscopy were used to observe the properties of cotton fabric after finishing, such as concentration of chlorine on cotton fabric, morphological properties of the surface of cotton fabric and functional groups on the cotton fabric. The results showed that cotton fabric coated with DMH followed with chlorination has antimicrobial properties that are able to resist S. aureus and this property is rechargeable.

Description: The catalytic and non-catalytic pyrolysis of microcrystalline cellulose and phosphoric acid pre-treated cellulose was investigated. The thermal processes were carried out applying two different methodologies: conventional fast pyrolysis and microwave-induced pyrolysis. For the catalytic experiments different catalysts were evaluated: CeO 2 , Nb 2 O 5 , SiO 2 , high surface area SiO 2 , Si-MCM-48 and Al-Fe-MCM-48. In all cases the liquid fraction was evaluated by quantifying the yields of anhydrosugars (mainly levoglucosan, levoglucosenone and 1,4:3,6-dianhydro-α- d -glucopyranose) and aromatic hydrocarbons. In the reaction of microcrystalline cellulose levoglucosan was the main product, while levoglucosenone was predominant in the pyrolysis of phosphoric acid pre-treated cellulose. Catalysts improved the fraction of bio-oil and the product distribution depended on the nature of catalytic materials as well as the starting cellulose. On the other hand, the microwave induced pyrolysis favored the formation of char at expenses of liquid fraction. In this case levoglucosenone and other anhydrosugars in conjunction with furan compounds were the main products.

Description: Osteolytic bone diseases are characterized by excessive osteoclast formation and activation. Protein kinase C (PKC)-dependent pathways regulate cell growth, differentiation and apoptosis in many cellular systems, and have been implicated in cancer development and osteoclast formation. A number of PKC inhibitors with anti-cancer properties have been developed, but whether they might also influence osteolysis (a common complication of bone invading cancers) is unclear. We studied the effects of the PKC inhibitor compound, GF109203X on osteoclast formation and activity, processes driven by receptor activator of NFκB ligand (RANKL). We found that GF109203X strongly and dose dependently suppresses osteoclastogenesis and osteoclast activity in RANKL-treated primary mouse bone marrow cells. Consistent with this GF109203X reduced expression of key osteoclastic genes, including cathepsin K, calcitonin receptor, tartrate resistant acid phosphatase (TRAP) and the proton pump subunit V-ATPase-d2 in RANKL-treated primary mouse bone marrow cells. Expression of these proteins is dependent upon RANKL-induced NF-κB and NFAT transcription factor actions; both were reduced in osteoclast progenitor populations by GF109203X treatment, notably NFATc1 levels. Furthermore, we showed that GF109203X inhibits RANKL-induced calcium oscillation. Together, this study shows GF109203X may block osteoclast functions, suggesting that pharmacological blockade of PKC-dependent pathways has therapeutic potential in osteolytic diseases. J. Cell. Physiol. © 2014 Wiley Periodicals, Inc.

Description: The sesquiterpene lactone Parthenolide (PN) exerted a cytotoxic effect on MDA-MB231 cells, a triple-negative breast cancer (TNBC) cell line, but its effectiveness was scarce when employed at low doses. This represents an obstacle for a therapeutic utilization of PN. In order to overcome this difficulty we associated to PN the suberoylanilide hydroxamic acid (SAHA), an histone deacetylase inhibitor. Our results show that SAHA synergistically sensitized MDA-MB231 cells to the cytotoxic effect of PN. It is noteworthy that treatment with PN alone stimulated the survival pathway Akt/mTOR and the consequent nuclear translocation of Nrf2, while treatment with SAHA alone induced autophagic activity. However when the cells were treated with SAHA/PN combination, SAHA suppressed PN effect on Akt/mTOR/Nrf2 pathway, while PN reduced the prosurvival autophagic activity of SAHA. In addition SAHA/PN combination induced GSH depletion, fall in Δψm, release of cytochrome c, activation of caspase 3 and apoptosis. Finally we demonstrated that combined treatment maintained both hyperacetylation of histones H3 and H4 induced by SAHA and down-regulation of DNMT1 expression induced by PN. Inhibition of the DNA-binding activity of NF-kB, which is determined by PN, was also observed after combined treatment. In conclusion, combination of PN to SAHA inhibits the cytoprotective responses induced by the single compounds, but does not alter the mechanisms leading to the cytotoxic effects. Taken together our results suggest that this combination could be a candidate for TNBC therapy. J. Cell. Physiol. © 2014 Wiley Periodicals, Inc.

Description: Herein, the microwave-assisted grafting method was employed for the development of a novel pH-responsive graft copolymer derived from polyacrylamide-modified hydroxypropyl methyl cellulose [g-HPMC (M)]. The synthesised copolymer has been used for in vitro sustained release of ornidazole. Various characterizations confirm the formation of graft copolymer. Swelling studies indicate the pH-dependent swelling behaviour, while deswelling studies suggest that g-HPMC (M) shows faster deswelling in response to change in pH and/temperature. The cell viability study signifies that g-HPMC (M) is cytocompatible. The in-vitro release study demonstrates that g-HPMC (M) delivers ornidazole specifically in the colon pH, without release of the drug in the acidic environment, ensuring g-HPMC (M) as an ideal candidate for orally administered colonic drug carriers. The kinetics and mechanism of drug release suggest that it follows a non-Fickian release mechanism.

Description: The effect of the fibrillation process through a twin-screw extruder (TSE) on properties of pulp fibers was studied, considering the degree of both fibrillation and degradation of the fibers. Never-dried refined bleached kraft pulp (NBKP) was passed through a TSE several times at a high concentration of 28 wt%. The output of fibrillated fibers had a solid content up to ca. 50 wt%, and the material was in powder form. Characterizations of the morphology, dewatering speed, sedimentation, laser light scattering, scanning electron microscopy of cellulose suspensions, and light transmittance of resin-impregnated films showed that the fibrillation degree of the pulp was enhanced with a higher number of passes. However, the results from thermogravimetry, intrinsic viscosity, and X-ray diffraction analyses indicated that some degradation occurred during the fibrillation process in the TSE. In addition, the mechanical properties of the fibrillated pulp sheets reflected the effects of treatment on the fibrillation and degradation of the cellulose. For never-dried refined NBKP pulp, the best compromise in terms of fibrillation and degradation degree is between 3 and 14 passes, depending on the envisaged properties and applications. The possibility of nanocellulose production at the reported high solid contents is of great interest for industry.

Description: Genomic and trascriptomic profiling has recently contributed details to the characterization of luminal B breast cancer. We explored the contribution of anthropometric, metabolic and molecular determinants to the multifaceted heterogeneity of this breast cancer subtype, with a specific focus on the association between body mass index (BMI), pre-treatment fasting glucose, hormone receptors and expression of human epidermal growth factor receptor 2 (HER2). Extensively annotated specimens were obtained from 154 women with luminal B breast cancer diagnosed at two Italian comprehensive cancer centres. Participants' characteristics were descriptively analyzed overall and by HER2 status (positive vs negative). BMI (〈25 vs ≥25), pre-treatment fasting glucose (〈median value of 94 mg/dl vs ≥94) and percentage of hormone receptors were tested for association with HER2 expression in regression models. In univariate models, BMI, fasting glucose and, at a lesser extent, percentage of estrogen receptors (ER) were significantly and inversely associated with HER2 expression (OR: 0.32, 95%CI: 0.16-0.66; 0.43, 0.23-0.0.82; 0.96, 0.94-0.97, respectively). The multivariate models confirmed the protective role of BMI and ER on HER2 expression, with luminal B HER2 positive patients being significantly less frequent among women within the highest category of BMI and percentage expression of ER compared with their counterparts (OR: 0.22, 95%CI: 0.09-0.53; 0.95, 0.93-0.97). In conclusions, BMI and percentage of ER representation are inversely associated with HER2 expression in luminal B breast cancers. Upon confirmatory findings, this might help identify patient subgroups who may best benefit from the use of interventions targeting insulin resistance in well depicted breast cancer scenarios. This article is protected by copyright. All rights reserved

Description: Histone deacetylases (HDACs) play a crucial role in the regulation of gene expression through remodeling of chromatin structures. However, the molecular mechanisms involved in this event remain unknown. In this study, we sought to examine whether HDAC inhibition-mediated protective effects involved HDAC4 sumoylation, degradation, and the proteasome pathway. Isolated neonatal mouse ventricular myocytes (NMVM) and H9c2 cardiomyoblasts were subjected to 48 hours of hypoxia (H) (1% O 2 ) and 2 hours of reoxygenation (R). Treatment of cardiomyocytes with trichostatin A (TSA) attenuated H/R-elicited injury, as indicated by a reduction of lactate dehydrogenase (LDH) leakage, an increase in cell viability, and decrease in apoptotic positive cardiomyocytes. MG132, a potent proteasome pathway inhibitor, abrogated TSA-induced protective effects, which was associated with the accumulation of ubiquitinated HDAC4. NMVM transduced with adenoviral HDAC4 led to an exaggeration of H/R-induced injury. TSA treatment resulted in a decrease in HDAC4 in cardiomyocytes infected with adenoviral HDAC4, and HDAC4-induced injury was attenuated by TSA. HDAC inhibition resulted in a significant reduction in reactive oxygen species (ROS) in cardiomyoblasts exposed to H/R, which was attenuated by blockade of the proteasome pathway. Cardiomyoblasts carrying wild type and sumoylation mutation (K559R) were established to examine effects of HDAC4 sumoylation and ubiquitination on H/R injury. Disruption of HDAC4 sumoylation brought about HDAC4 accumulation and impairment of HDAC4 ubiquitination in association with enhanced susceptibility of cardiomyoblasts to H/R. Taken together, these results demonstrated that HDAC inhibition stimulates proteasome dependent degradation of HDAC4, which is associated with HDAC4 sumoylation to induce these protective effects. This article is protected by copyright. All rights reserved

Description: Endothelial cells play a major role in the initiation and perpetuation of the inflammatory process in health and disease, including their pivotal role in leukocyte recruitment. The role of pro-inflammatory transcription factors in this process has been well-described, including NF-κB. However, much less is known regarding transcription factors that play an anti-inflammatory role in endothelial cells. Myocyte enhancer factor 2 C (MEF2C) is a transcription factor known to regulate angiogenesis in endothelial cells. Here, we report that MEF2C plays a critical function as an inhibitor of endothelial cell inflammation. Tumor necrosis factor (TNF)-α inhibited MEF2C expression in endothelial cells. Knockdown of MEF2C in endothelial cells resulted in the upregulation of pro-inflammatory molecules and stimulated leukocyte adhesion to endothelial cells. MEF2C knockdown also resulted in NF-κB activation in endothelial cells. Conversely, MEF2C overexpression by adenovirus significantly repressed TNF-α induction of pro-inflammatory molecules, activation of NF-κB, and leukocyte adhesion to endothelial cells. This inhibition of leukocyte adhesion by MEF2C was partially mediated by induction of KLF2. In mice, lipopolysaccharide (LPS)-induced leukocyte adhesion to the retinal vasculature was significantly increased by endothelial cell-specific ablation of MEF2C. Taken together, these results demonstrate that MEF2C is a novel negative regulator of inflammation in endothelial cells and may represent a therapeutic target for vascular inflammation. This article is protected by copyright. All rights reserved

Description: 1-Butyl-3-methylimidazolium chloride ([BMIM]Cl) was selected as co-solvent to dissolve cellulose and silk fibroin and the cellulose/silk fibroin blend fibers were fabricated with dry-jet wet spinning technology. The phase morphology of cellulose and silk fibroin in the blend fibers was studied by scanning electron microcopy and laser scanning confocal microscope. It is shown that the cellulose is in the continuous phase and silk fibroin exists as “fibril-like” in cellulose, in which the radial dimension of silk fibroin phase is 0.5–1.0 μm. The phase size of silk fibroin along the fiber axis increased with the increase of silk fibroin content and draw ratio. From the wide-angle X-ray scattering, it is found that the total crystallinity of the blend fibers decreased with increasing silk fibroin content. The hydrogen bond between cellulose and silk fibroin was observed from Fourier transform infrared spectra. Although the tensile strength and initial modulus of blend fibers decreased with increasing silk fibroin content, the tensile strength of blend fibers contain 35 wt% silk fibroin was up to 191 MPa.