bluuebunny/crossref_metadata_2025 huggingface dataset:
Gamma‐tocotrienol induces apoptosis and autophagy in prostate cancer cells by increasing intracellular dihydrosphingosine and dihydroceramide
Authors: Jiang Qing , Rao Xiayu , Kim Choon Young , Freiser Helene , Zhang Qingbo , Jiang Ziying , Li Guilan
Published: March 2011

Although cell‐based studies have shown that γ‐tocotrienol (γTE) exhibits stronger anticancer activities than other forms of vitamin E including γ‐tocopherol (γT), the molecular bases underlying γTE‐exerted effects remains to be elucidated. Here we showed that γTE treatment promoted apoptosis, necrosis and autophagy in human prostate PC‐3 and LNCaP cancer cells. In search of potential mechanisms of γTE‐provoked effects, we found that γTE treatment led to marked increase of intracellular dihydroceramide and dihydrosphingosine, the sphingolipid intermediates in de novo sphingolipid synthesis pathway but had no effects on ceramide or sphingosine. The elevation of these sphingolipids by γTE preceded or coincided with biochemical and morphological signs of cell death and was much more pronounced than that induced by γT, which accompanied with much higher cellular uptake of γTE than γT. The importance of sphingolipid accumulation in γTE‐caused fatality was underscored by the observation that dihydrosphingosine and dihydroceramide potently reduced the viability of both prostate cell lines and LNCaP cells, respectively. In addition, myriosin, a specific inhibitor of de novo sphingolipid synthesis, counteracted γTE‐induced cell death. In agreement with these cell‐based studies, γTE inhibited LNCaP xenograft growth by 53% (p < 0.05), compared to 33% (p = 0.07) by γT, in nude mice. These findings provide a molecular basis of γTE‐stimulated cancer cell death and support the notion that elevation of intracellular dihydroceramide and dihydrosphingosine is likely a novel anticancer mechanism.
Cytotoxic activity of the histone deacetylase inhibitor panobinostat (LBH589) in anaplastic thyroid cancer in vitro and in vivo
Authors: Catalano Maria Graziella , Pugliese Mariateresa , Gargantini Eleonora , Grange Cristina , Bussolati Benedetta , Asioli Sofia , Bosco Ornella , Poli Roberta , Compagnone Alessandra , Bandino Andrea , Mainini Franco , Fortunati Nicoletta , Boccuzzi Giuseppe
Published: March 2011

Anaplastic thyroid carcinoma (ATC) has a rapidly fatal clinical course, being resistant to multimodal treatments. Microtubules, α/β tubulin heterodimers, are crucial in cell signaling, division and mitosis and are among the most successful targets for anticancer therapy. Panobinostat (LBH589) is a potent deacetylase inhibitor acting both on histones and nonhistonic proteins, including α‐tubulin. In vitro LBH589, evaluated in three ATC cell lines (BHT‐101, CAL‐62 and 8305C), resulted in impairment of cell viability, inhibition of colony formation, cell cycle arrest and apoptosis induction. Mechanistically, we showed that LBH589 not only affected the expression of p21 and cyclin D1, but markedly determined microtubule stabilization as evidenced by tubulin acetylation and increased tubulin polymerization. In a SCID xenograft model implanted with CAL‐62 cells, the cytotoxic properties of LBH589 were confirmed. The drug at the dose of 20 mg/kg significantly impaired tumor growth (final tumor volume 2.5‐fold smaller than in untreated animals); at this dose, no relevant side effects were observed. In tumors of treated animals, a significant reduction of Ki67, which was negatively correlated with tubulin acetylation, was observed. Moreover, acetyl‐tubulin levels negatively correlated with tumor volume at sacrifice, reinforcing the opinion that tubulin acetylation has a role in the inhibition of tumor growth. In conclusion, LBH589, acting on both histones and nonhistonic proteins in anaplastic thyroid cancer, appears to be a promising therapeutic agent for the treatment of this kind of cancer which is known not to respond to conventional therapy.
Dysregulation of microRNA‐204 mediates migration and invasion of endometrial cancer by regulating FOXC1
Authors: Chung T.K.H. , Lau T.S. , Cheung T.H. , Yim S.F. , Lo K.W.K. , Siu N.S.S. , Chan L.K.Y. , Yu M.Y. , Kwong J. , Doran G. , Barroilhet L.M. , Ng A.S.W. , Wong R.R.Y. , Wang V.W. , Mok S.C. , Smith D.I. , Berkowitz R.S. , Wong Y.F.
Published: March 2011

MicroRNAs (miRNAs) regulate mRNA stability and protein expression, and certain miRNAs have been demonstrated to act either as oncogenes or tumor suppressors. Differential miRNA expression signatures have been documented in many human cancers but the role of miRNAs in endometrioid endometrial cancer (EEC) remains poorly understood. This study identifies significantly dysregulated miRNAs of EEC cells, and characterizes their impact on the malignant phenotype. We studied the expression of 365 human miRNAs using Taqman low density arrays in EECs and normal endometriums. Candidate differentially expressed miRNAs were validated by quantitative real‐time PCR. Expression of highly dysregulated miRNAs was examined in vitro through the effect of anti‐/pre‐miRNA transfection on the malignant phenotype. We identified 16 significantly dysregulated miRNAs in EEC and 7 of these are novel findings with respect to EEC. Antagonizing the function of miR‐7, miR‐194 and miR‐449b, or overexpressing miR‐204, repressed migration, invasion and extracellular matrix‐adhesion in HEC1A endometrial cancer cells. FOXC1 was determined as a target gene of miR‐204, and two binding sites in the 3′‐untranslated region were validated by dual luciferase reporter assay. FOXC1 expression was inversely related to miR‐204 expression in EEC. Functional analysis revealed the involvement of FOXC1 in migration and invasion of HEC1A cells. Our results present dysfunctional miRNAs in endometrial cancer and identify a crucial role for miR‐204‐FOXC1 interaction in endometrial cancer progression. This miRNA signature offers a potential biomarker for predicting EEC outcomes, and targeting of these cancer progression‐ and metastasis‐related miRNAs offers a novel potential therapeutic strategy for the disease.
Carcinogenetic risk estimation based on quantification of DNA methylation levels in liver tissue at the precancerous stage
Authors: Nagashio Ryo , Arai Eri , Ojima Hidenori , Kosuge Tomoo , Kondo Yutaka , Kanai Yae
Published: March 2011

For appropriate surveillance of patients at the precancerous stage for hepatocellular carcinomas (HCCs), carcinogenetic risk estimation is advantageous. The aim of our study was to establish criteria for such estimation based on DNA methylation profiling. The DNA methylation status of 203 CpG sites on 25 bacterial artificial chromosome (BAC) clones, whose DNA methylation status had been proven to discriminate samples of noncancerous liver tissue obtained from patients with HCC (N) from normal liver tissue (C) samples by BAC array‐based methylated CpG island amplification, was evaluated quantitatively using pyrosequencing. The 45 CpG sites whose DNA methylation levels differed significantly between C and N in the learning cohort (n = 22) were identified. The criteria combining DNA methylation status for the 30 regions including the 45 CpG sites were able to diagnose N as being at high risk of carcinogenesis with 100% sensitivity and specificity in the learning cohort and 95.6% sensitivity and 100% specificity in the validation (n = 90) cohort. DNA methylation status for the 30 regions in N samples was significantly correlated with the outcome of patients with HCCs, indicating that clinicopathologically valid DNA methylation alterations have already accumulated at the precancerous stage. The DNA methylation status of the 30 regions did not depend on the presence or absence of hepatitis virus infection, or the status of noncancerous liver tissue (chronic hepatitis or cirrhosis). These criteria may be applicable for carcinogenetic risk estimation using liver biopsy specimens obtained from patients who are followed up because of chronic liver diseases.
MicroRNA profiles of prostate carcinoma detected by multiplatform microRNA screening
Authors: Wach Sven , Nolte Elke , Szczyrba Jaroslaw , Stöhr Robert , Hartmann Arndt , Ørntoft Torben , Dyrskjøt Lars , Eltze Elke , Wieland Wolf , Keck Bastian , Ekici Arif B. , Grässer Friedrich , Wullich Bernd
Published: March 2011

MicroRNAs (miRNAs) are small RNA molecules that regulate gene expression via posttranscriptional inhibition of protein synthesis. They play a vital role in tumorigenesis. To characterize the diagnostic potential of miRNAs in prostate cancer, a leading cause of cancer mortality, we performed screening of miRNA expression profiles. We used commercially available microarrays to establish miRNA expression profiles from a cohort of 20 cancer samples. The expression of selected miRNAs was analyzed by quantitative real‐time PCR and the identity of miRNA expressing cells was determined by miRNAin situhybridization. We identified 25 miRNAs that showed a significant differential expression in cancer samples. The comparison with previously published data generated by deep sequencing of cDNA libraries of small RNA molecules revealed a concordance rate of 47% among miRNAs identified with both techniques. The differential expression of miRNAsmiR‐375,miR‐143andmiR‐145was validated by quantitative PCR. MiRNAin situhybridization revealed that the differential expression is cancer‐cell associated. A combination of three miRNAs correctly classified tissue samples with an accuracy of 77.6% with an area under the receiver–operator characteristic curve of 0.810. Our data extend the knowledge about the deregulation of miRNAs in prostate cancer. The differential expression of several miRNAs is highly consistent using independent cohorts of tumor samples, different tissue preservation methods and different experimental methods. Our results indicate that combinations of miRNAs are promising biomarkers for the diagnosis of prostate cancer.
Down‐regulation of Thanatos‐associated protein 11 by BCR‐ABL promotes CML cell proliferation through c‐Myc expression
Authors: Nakamura Satoki , Yokota Daisuke , Tan Lin , Nagata Yasuyuki , Takemura Tomonari , Hirano Isao , Shigeno Kazuyuki , Shibata Kiyoshi , Fujisawa Shinya , Ohnishi Kazunori
Published: March 2011

Bcr‐Abl activates various signaling pathways in chronic myelogenous leukemia (CML) cells. The proliferation of Bcr‐Abl transformed cells is promoted by c‐Myc through the activation of Akt, JAK2 and NF‐κB. However, the mechanism by which c‐Myc regulates CML cell proliferation is unclear. In our study, we investigated the role of Thanatos‐associated protein 11 (THAP11), which inhibits c‐Myc transcription, in CML cell lines and in hematopoietic progenitor cells derived from CML patients. The induction of THAP11 expression by Abl kinase inhibitors in CML cell lines and in CML‐derived hematopoietic progenitor cells resulted in the suppression of c‐Myc. In addition, over‐expression of THAP11 inhibited CML cell proliferation. In colony forming cells derived from CML‐aldehyde dehydrogenase (ALDH)hi/CD34+ cells, treatment with Abl kinase inhibitors and siRNA depletion of Bcr‐Abl induced THAP11 expression and reduced c‐Myc expression, resulting in inhibited colony formation. Moreover, overexpression of THAP11 significantly decreased the colony numbers, and also inhibited the expression of c‐myc target genes such as Cyclin D1, ODC and induced the expression of p21Cip1. The depletion of THAP11 inhibited JAK2 or STAT5 inactivation‐mediated c‐Myc reduction in ALDHhi/CD34+ CML cells. Thus, the induced THAP11 might be one of transcriptional regulators of c‐Myc expression in CML cell. Therefore, the induction of THAP11 has a potential possibility as a target for the inhibition of CML cell proliferation.
Risk of liquidity and contagion of the crisis on the United States, United Kingdom and euro zone money markets
Authors: Blancheton Bertrand , Bordes Christian , Maveyraud Samuel , Rous Philippe
Published: March 2011

The financial crisis has produced a generalized rise of the liquidity risk on the money markets. The purpose of this article is to highlight the mechanisms of contagion between the money markets of the United States, the United Kingdom and the Euro Zone. To give an account of these mechanisms, a BEKK model, in which we introduce a structural break, is adopted. Thus, this model explicitly tests the spillover effects of the liquidity risk premium on money markets. The results show that before the financial crisis (i.e. the reference period), there is a recursive propagation process between the Euro€ and the BP£ zones, a propagation process between the BP£ and the US$ areas and an obvious spread of volatilities from the EU€ zone towards the US$ zone;. During the crisis period, the liquidity problems start from the US money market to the UK£ and EU€ money markets. Copyright © 2011 John Wiley & Sons, Ltd.
On finding an orthogonal convex skull of a digital object
Authors: Dutt Mousumi , Biswas Arindam , Bhowmick Partha , Bhattacharya Bhargab B.
Published: March 2011

A combinatorial algorithm to compute an orthogonal convex skull of a digital object imposed on the background grid is presented in this paper. The proposed algorithm has the time complexity of O(n log n), which improves the earlier method of O(n2) time complexity for finding the convex skull of a simple orthogonal polygon. A set of rules is formulated first and then an orthogonal convex skull is derived by applying these rules while traversing along the boundary of the inner orthogonal polygon that tightly inscribes the given digital object. The algorithm uses only comparison and addition in the integer domain, which makes it amenable to fast real‐world applications. Experimental results on different shapes have also been presented to demonstrate the efficacy and elegance of the proposed technique. © 2011 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 21, 14–27, 2011.
Development of a compliant and cytocompatible micro‐fibrous polyethylene terephthalate vascular scaffold
Authors: Moreno M. J. , Ajji A. , Mohebbi‐Kalhori D. , Rukhlova M. , Hadjizadeh A. , Bureau M. N.
Published: March 2011

Bioengineering approaches have been intensively applied to create small diameter vascular grafts using artificial materials. However, a fully successful, high performing and anti‐thrombogenic structure has not been achieved yet. In this study, we have designed and fabricated a novel non‐woven fibrous vascular graft with biomechanical properties closely resembling those of native vessels. Vascular cell growth, preservation of cell phenotype, retention of vasoactive properties, as well as the effect of gelatin coating on the cellular interaction with the scaffolds under static and shear stress conditions were investigated. The non‐woven fibrous scaffolds were made from melt blown polyethylene terephthalate fiber webs stacked by means of a consolidation technique. The scaffold variables were fiber diameter distribution and the number of consolidated web stacks. SEM analysis confirmed various fiber diameter and pore size ranges corresponding to the different conditions. The scaffolds showed burst pressure values of ∼1500 mmHg and compliance (8.4 ± 1.0 × 10−2% mmHg−1) very similar to those of native arteries (∼8 × 10−2% mmHg−1). The structure with the smallest fiber diameter range (1–5 μm) and pore size range (1–20 μm) was the most suitable for the growth of human brain endothelial cells and aortic smooth muscle cells. The cells maintained their specific cell phenotype, expressed collagen and elastin and produced cAMP in response to α‐calcitonin gene‐related peptide. However, under shear stress conditions (0.9 dyne cm−2), only 30% of the cells were retained in both uncoated and gelatin‐coated scaffolds indicating the need for improving the cell retention capacity of these structures, which is our future research direction. This study indicates that the biomechanical and biocompatible properties of this novel vascular scaffold are promising for the development of a vascular graft with similar characteristics to those of native vessels. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2011.
Lentiviral vector‐mediated siRNA knockdown and concurrent rescue of Murine CIN85
Authors: Wang Yumei , Zhang Xiaoan , Zhang Qinxian , Sheng Guangyao
Published: March 2011

RNA interference (RNAi), an evolutionarily conserved process of gene silencing, is now a common tool in gene functional studies. However, potential “off‐target effects” is one of major concerns in RNAi experiment associated with false positive results. Apart from continuing improvement in small interfering RNA (siRNA) designs, there is no method available to prevent the generation of “off‐target effects” resulted from possible identity between siRNA and abundant cellular mRNA transcripts. In the present study, we have developed a lentiviral vector‐mediated system that allows efficient siRNA silencing and concurrent rescue of targeted genes. While this approach does not eliminate potential “off‐target effects,” concurrent rescue of a target gene allows a definite judgment with regard to a phenotype change, either from expected siRNA silencing or “off‐target effects.” The system has been validated with murine CIN85 gene and may be generally applicable in molecular studies from broad fields. © 2011 Wiley Periodicals, Inc. J Biochem Mol Toxicol 25:55–59 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.20331
Initial CD34+ cell‐enrichment of cord blood determines hematopoietic stem/progenitor cell yield upon Ex vivo expansion
Authors: Andrade Pedro Z. , da Silva Cláudia Lobato , dos Santos Francisco , Almeida‐Porada Graça , Cabral Joaquim M.S.
Published: March 2011

Since umbilical cord blood (UCB), contains a limited hematopoietic stem/progenitor cells (HSC) number, successful expansion protocols are needed to overcome the hurdles associated with inadequate numbers of HSC collected for transplantation. UCB cultures were performed using a human stromal‐based serum‐free culture system to evaluate the effect of different initial CD34+ cell enrichments (Low: 24 ± 1.8%, Medium: 46 ± 2.6%, and High: 91 ± 1.5%) on the culture dynamics and outcome of HSC expansion. By combining PKH tracking dye with CD34+ and CD34+CD90+ expression, we have identified early activation of CD34 expression on CD34− cells in Low and Medium conditions, prior to cell division (35 ± 4.7% and 55 ± 4.1% CD34+ cells at day 1, respectively), affecting proliferation/cell cycle status and ultimately determining CD34+/CD34+CD90+ cell yield (High: 14 ± 1.0/3.5 ± 1.4‐fold; Medium:22 ± 2.0/3.4 ± 1,0‐fold; Low:31 ± 3.0/4.4 ± 1.5‐fold) after a 7‐day expansion. Considering the potential benefits of using expanded UCB HSC in transplantation, here we quantified in single UCB units, the impact of using one/two immunomagnetic sorting cycles (corresponding to Medium and High initial progenitor content), and the average CD34+ cell recovery for each strategy, on overall CD34+ cell expansion. The higher cell recovery upon one sorting cycle lead to higher CD34+ cell numbers after 7 days of expansion (30 ± 2.0 vs. 13 ± 1.0 × 106 cells). In particular, a high (>90%) initial progenitor content was not mandatory to successfully expand HSC, since cell populations with moderate levels of enrichment readily increased CD34 expression ex‐vivo, generating higher stem/progenitor cell yields. Overall, our findings stress the importance of establishing a balance between the cell proliferative potential and cell recovery upon purification, towards the efficient and cost‐effective expansion of HSC for cellular therapy. J. Cell. Biochem. 112: 1822–1831, 2011. © 2011 Wiley‐Liss, Inc.
CCN6 enhances ICAM‐1 expression and cell motility in human chondrosarcoma cells
Authors: Fong Yi‐Chin , Lin Chih‐Yang , Su Yi‐Chang , Chen Wen‐Chi , Tsai Fuu‐Jen , Tsai Chang‐Hai , Huang Chih‐Yang , Tang Chih‐Hsin
Published: March 2011

Chondrosarcoma is a type of highly malignant tumor with a potent capacity to invade locally and cause distant metastasis. Chondrosarcoma shows a predilection for metastasis to the lungs. CCN6 is a cysteine‐rich protein that belongs to the CCN (Cyr61, CTGF, and Nov) family of matricellular proteins. However, the effects of CCN6 on human chondrosarcoma cells are largely unknown. In this study, we found that CCN6 increased the migration and the expression of intercellular adhesion molecule‐1 (ICAM‐1) in human chondrosarcoma cells. αvβ3 and αvβ5 integrin monoclonal antibody and mitogen‐activated protein kinase (MEK) inhibitors (PD98059 and U0126) inhibited the CCN6‐induced increase of the migration and ICAM‐1 up‐regulation of chondrosarcoma cells. CCN6 stimulation increased the phosphorylation of focal adhesion kinase (FAK), MEK, and extracellular signal‐regulated kinase (ERK). In addition, activator protein‐1 (AP‐1) inhibitors suppressed the cell migration and ICAM‐1 expression enhanced by CCN6. Moreover, CCN6 increased AP‐1 luciferase activity and binding of c‐Jun to the AP‐1 element on the ICAM‐1 promoter. Taken together, our results indicate that CCN6 enhances the migration of chondrosarcoma cells by increasing ICAM‐1 expression through the αvβ3 and αvβ5 integrin receptor, FAK, MEK, ERK, c‐Jun, and AP‐1 signal transduction pathway. J. Cell. Physiol. 227: 223–232, 2012. © 2011 Wiley Periodicals, Inc.
High cell density fermentation via a metabolically engineered Escherichia coli for the enhanced production of succinic acid
Authors: Wang Dan , Li Qiang , Song Ziyu , Zhou Wei , Su Zhiguo , Xing Jianmin
Published: March 2011

BACKGROUND: Succinic acid is a valuable four‐carbon organic chemical with applications in many fields. It was found that cell mass was an important factor in succinic acid production by metabolically engineered Escherichia coli strains. In this work, high cell density fermentation was investigated for succinic acid production by a metabolically engineered strain SD121 with ldhA, pflB, ptsG mutation and heterogenous cyanobacterial ppc overexpression.

RESULTS: Under two‐stage cultivation, the controlled DO feeding strategy during the aerobic growth phase facilitated biomass up to a dry cell weight of 19.6 g L−1, and enhanced succinic acid production in the following anaerobic fermentation phase to a concentration of 116.2 g L−1. A near theoretical maximum succinic acid yield of 1.73 mol mol−1 glucose was achieved with an average productivity of 1.55 g L−1 h−1.

CONCLUSION: The results indicated the potential advantage of high cell density fermentation for improvement of succinic acid production by E. coli. Copyright © 2010 Society of Chemical Industry
Hydrogel composites with temperature induced phase transition for biocatalysis
Authors: Wack Holger , Nellesen Anke , Schwarze‐Benning Kerstin , Deerberg Görge
Published: March 2011

BACKGROUND: This paper focuses on the development of temperature induced phase transition hydrogels based on poly(N‐isopropylocrylamide (PNIPA) copolymers and their application as an immobilization matrix for biocatalysts.

RESULTS: PNIPA‐co‐AAc and PNIPA‐co‐MAAc hydrogels were synthesized with different comonomer concentrations and analysed. In order to evaluate the capacity of hydrogels to take up or to release liquids the mass exchange capacity is introduced. In the presented work mass exchange capacities up to 22.4 were realized. To enhance the mechanical stability, composites of hydrogels and cellulosic fleeces were prepared. The enzyme Lipozyme® TL 100 L (Thermomyces languniosa Lipase) was successfully inserted into the hydrogels and into the hydrogel composites. Lipase‐catalysed transesterification of rapeseed oil with ethanol to the corresponding ethyl ester was investigated to prove the activity of immobilized enzyme and thus, the concept. The activity was found to be similar to that of free enzyme.

CONCLUSION: Smart hydrogel composites were used for the transesterification of oil. Based on the results obtained, reversible loadable and mechanical stable hydrogel composites could be developed for continuous working reactor concepts. Copyright © 2010 Society of Chemical Industry
Solid–liquid extraction of terbium from phosphoric acid solutions using solvent‐impregnated resin containing TOPS 99
Authors: Kumar Batchu Nagaphani , Radhika Surampally , Kantam Mannepalli Lakshmi , Reddy Bontha Ramachandra
Published: March 2011

BACKGROUND: In this work, the solid‐liquid extraction of terbium from phosphoric acid solutions using solvent‐impregnated resin containing TOPS 99, an equivalent of di‐2‐ethylhexyl phosphoric acid, has been investigated. The parameters studied include equilibration time, acid concentration, amount of resin, metal concentration, kinetics, temperature, loading, elution, regeneration and recycling.

RESULTS: FT‐IR results confirm the physical interaction of the extractant with the resin. The extraction of terbium with TOPS 99 impregnated Amberlite XAD 4 resin was acid dependent and transfer of metal follows a cation exchange mechanism. The loading capacity of TOPS 99‐impregnated resin for terbium was calculated to be 23.8 mg g−1 resin. Controlling mechanism of the adsorption was found to be a chemical reaction following pseudo‐second‐order kinetics. The endothermic nature of extraction was confirmed by temperature studies. Among the various eluants studied, H2SO4 was the best. Regeneration and recycling of the resin indicated the resin can be used for continuous cycles.

CONCLUSIONS: Terbium was successfully extracted from phosphoric acid using TOPS 99 extractant impregnated into Amberlite XAD4 with a maximum loading of 23.8 mg g−1 resin and fully recovered with 1 mol L−1sulfuric acid. The resin was subjected to seven cycles of extraction and elution without any loss of performance. Further studies showed that terbium could be separated from lutetium. Copyright © 2010 Society of Chemical Industry
Decomposition of hydrogen peroxide in the presence of activated carbons with different characteristics
Authors: Aguinaco Almudena , Pocostales Juan Pablo , García‐Araya Juan F. , Beltrán Fernando J.
Published: March 2011

BACKGROUND: Catalytic ozonation promoted by activated carbon is a promising advanced oxidation process used in water treatment. Hydrogen peroxide generated as a by‐product from the reaction of ozone with some surface groups on the activated carbon or from the oxidation of some organic compounds present in the water being treated seems to play a key role in the catalytic ozonation process. Hydrogen peroxide decomposition promoted by two granular activated carbons (GAC) of different characteristics (Hydraffin P110 and Chemviron SSP‐4) has been studied in a batch reactor. The operating variables investigated were the stirring speed, temperature, pH and particle size. Also, the influence of metals on the GAC surface, that can catalyze hydrogen peroxide decomposition, was observed.

RESULTS: Chemviron SSP‐4 showed a higher activity to decompose hydrogen peroxide than HydraffinP110 (70 and 50% of hydrogen peroxide removed after 2 h process, respectively). Regardless of the activated carbon used, hydrogen peroxide decomposition was clearly controlled by the mass transfer, although temperature and pH conditions exerted a remarkable influence on the process. Catalytic ozonation in the presence of activated carbon and hydrogen peroxide greatly improved the mineralization of oxalic acid (a very recalcitrant target compound). About 70% TOC (total organic carbon) depletion was observed after 1 h reaction in this combined system, much higher than the mineralization achieved by the single processes used.

CONCLUSIONS: Of the two activated carbons studied, Chemviron SSP‐4 with an acidic nature presented a higher activity to decompose hydrogen peroxide. However the influence of the operating variables was quite similar in both cases. Experiments carried out in the presence of tert‐butanol confirmed the appearance of radical species. A kinetic study indicated that the process was controlled by the internal mass transfer and the chemical reaction on the surface of the activated carbon. The catalytic activity of hydrogen peroxide in oxalic acid ozonation promoted by activated carbon (O3/AC/H2O2) was also studied. The results revealed the synergetic activity of the system O3/AC/H2O2 to remove oxalic acid. Copyright © 2010 Society of Chemical Industry
Sox‐9 facilitates differentiation of adipose tissue‐derived stem cells into a chondrocyte‐like phenotype in vitro
Authors: Yang Zhe , Huang Chun‐Yuh. Charles , Candiotti Keith A. , Zeng Xiaoling , Yuan Taiyi , Li Jinliang , Yu Hong , Abdi Salahadin
Published: March 2011

The purpose of this study is to test whether ectopic expression of Sox‐9 can induce adipose tissue‐derived stem cells (ASCs) to function as real nucleus pulposus (NP) cells in vitro. Adenoviral vectors expressing Sox‐9 were reported to infect the chondroblastic and human disc cells, which resulted in increased Sox‐9 and type II collagen production. ASCs were isolated from rat inguinal adipose pad, characterized, and transduced in vitro with a retroviral vector encoding the Sox‐9 gene. Sox‐9‐engineered ASCs (ASCs/Sox‐9) were induced for the chondrocyte‐like cell differentiation by 3D cultured in alginate beads and TGF‐β3 for 2 weeks. Expression of exogenous Sox‐9 protein was detected. Type II collagen and Aggrecan gene expressions of induced ASCs/Sox‐9 were measured using real‐time PCR; proteoglycans expressions were measured by checking the glycosaminoglycan content and type II collagen production by enzyme‐linked immunosorbent assay. Isolated ASCs were CD 29+/CD44+/C‐Kit−/Lin−/CD34−/CD45−. ASCs/Sox‐9 expressed marked increase in exogenous Sox‐9 protein. After induction, type II collagen gene expression was sevenfold higher in mRNA levels, with an approximately twofold increase in protein levels of ASCs/Sox‐9 compared to ASCs. Type II collagen and proteoglycan productions were significantly increased in the ASCs/Sox‐9 compared to the ASCs. In addition, co‐culture of induced ASCs/Sox‐9 with matured NP cells resulted in enhanced increase in proteoglycan and type II collagen production. Constitutive retroviral expression of Sox‐9 could efficiently induce ASCs differentiation into chondrocyte‐like cells. This novel approach may provide a practicable system for a simple and rapid differentiation of ASCs into chondrocyte‐like cells which may be potentially used as a stem cell‐based therapeutic tool for the treatment of degenerative disc diseases. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 1291–1297, 2011
Histopathological, clinical, and electrophysiological features influencing postoperative outcomes in carpal tunnel syndrome
Authors: Galasso Olimpio , Mariconda Massimo , Donato Giuseppe , Di Mizio Giulio , Padua Luca , Brando Antonio , Conforti Francesco , Valentino Paola , Gasparini Giorgio
Published: March 2011

Data on the outcome predictors of surgical result of carpal tunnel syndrome (CTS) is sparse and often conflicting. The purpose of this prospective comparative study was to evaluate the neurophysiologic findings and histological characteristics of the flexor tenosynovium in patients with CTS, assessing possible associations between these findings and preoperative patient status or surgical outcome. We evaluated 30 consecutive patients with a diagnosis of idiopathic CTS who were referred for surgery. Demographic data, subjective and objective data, and responses on an expanded assessment set, were collected before and 6 months after surgery. All patients underwent diagnostic neurophysiological testing prior to surgery, and histological analysis of tenosynovium specimens that were removed during surgery. Ten fresh‐frozen cadavers served as controls. There was significant improvement in most of the disease specific (Boston questionnaire and Hi‐Ob scale) and health generic (SF‐36 questionnaire) evaluation tools used in the study at the 6‐month follow‐up. Vascular changes were noted in the tenosynovium of the flexor tendon of patients with CTS when compared with controls. Greater synovial vascularization was negative predictor of the SF‐36's physical summary score before surgery. Bilateral presentation of symptoms and low nerve conduction velocity were negative predictors of the quality of life of patients after surgery for CTS. These findings have to be considered when discussing with patients as for the expected and desired outcomes of CTS surgery. The increased vascularization of flexor tenosynovium is associated with patients' functional status. © 2011 Orthopaedic Research Society Published by Wiley Periodicals, Inc. J Orthop Res 29: 1298–1304, 2011
Network meta‐analysis of parametric survival curves
Authors: Ouwens Mario J. N. M. , Philips Zoe , Jansen Jeroen P.
Published: March 2011

To inform health‐care decision‐making, treatments are often compared by synthesizing results from a number of randomized controlled trials. The meta‐analysis may not only be focused on a particular pairwise comparison, but can also include multiple treatment comparisons by means of network meta‐analysis.

For time‐to‐event outcomes such as survival, pooling is typically based on the hazard ratio (HR). The proportional hazards assumption that underlies current approaches of evidence synthesis is not only often implausible, but can also have a huge impact on decisions based on differences in expected outcomes, such as cost‐effectiveness analysis. The application of a constant HR implies the assumption that the treatment only has an effect on one characteristic of the survival distribution, while commonly used survival distributions, like the Weibull distribution, have both a shape and a scale parameter.

Instead of using constant HRs, this paper proposes meta‐analysis of treatment effects based on the shape and scale parameters of parametric survival curves. The model for meta‐analysis is extended for network meta‐analysis and illustrated with an example. Copyright © 2011 John Wiley & Sons, Ltd.
Tumor vascularization and histopathologic regression of soft tissue sarcomas treated with isolated limb perfusion with TNF‐α and melphalan
Authors: Grabellus Florian , Kraft Corinna , Sheu‐Grabellus Sien‐Yi , Bauer Sebastian , Podleska Lars E. , Lauenstein Thomas C. , Pöttgen Christoph , Konik Margarethe J. , Schmid Kurt W. , Taeger Georg
Published: March 2011

Background

Isolated limb perfusion (TM‐ILP) achieves high response rates in soft tissue sarcomas (STS). Some tumors show an insufficient association between radiological and pathological response. We investigated STS after TM‐ILP with a primary emphasis on histologic regression patterns.

Methods

In 53 patients with STS, TM‐ILP with subsequent tumor resection was performed. Regression was assessed by the Salzer‐Kuntschik regression scale. Microvessel density (MVD) of primary biopsies of 37 patients was determined by immunohistochemistry. Tumor regression was correlated with MVD of primary biopsies and other clinico‐pathological parameters.

Results

Regression presented mainly as necrosis or fibrosis/sclerosis upon histopathology. MFH, leiomyosarcoma, or clear cell sarcoma (CCS) responded well; whereas liposarcomas, synovial sarcomas, or MPNST were poor responders. MFH often had abundant necrosis; while other STS mainly presented with fibrosis/sclerosis. MVD had no influence on regression grade but modulated histologic regression patterns. Excellent regression demonstrated a trend toward an association with improved survival and local control.

Conclusion

TM‐ILP yielded high response rates in STS. Regression after TM‐ILP exhibits MVD‐dependent histopathologic patterns and variable efficacy in different sarcoma types. Complete regression seems to be a favorable prognostic factor. A concerted consideration of histopathology and clinical findings may contribute to a better clinical assessment of regression after TM‐ILP. J. Surg. Oncol. 2011; 103:371–379. © 2011 Wiley‐Liss, Inc.
Tracer agents for the detection of sentinel lymph nodes in breast cancer: Current concerns and directions for the future
Authors: Kelley Leah M. , Holmes Dennis R.
Published: March 2011

Tracer agents play a central role in axillary lymphatic mapping for sentinel node identification during breast cancer surgery. This article reviews the data concerning safety, efficacy, and availability of tracers currently in use. Alternate tracer materials are introduced, with review of the current literature. J. Surg. Oncol. 2011;104:91–96. © 2011 Wiley‐Liss, Inc.
Separation of regioisomers and enantiomers of underivatized saturated and unsaturated fatty acid monoacylglycerols using enantioselective HPLC
Authors: García Patricia , Franco Pilar , Álvarez Rosana , de Lera Ángel R.
Published: March 2011

The challenging separation of regioisomers and enantiomers of monoacylglycerols (MAGs) of fatty acids has been achieved using a single chiral HPLC column (Chiralpak® IC or Chiralpak® IA) and hexane/2‐propanol eluent mixtures, without previous derivatization of the samples. The efficacy of the method is independent of the chain length and the degree of unsaturation of the fatty acids of the MAG. In addition, the separation method allows monitoring the time course for the loss of enantiomeric purity of the fatty acid‐derived MAGs in polar hydroxylic solvents.
Cytokine Loaded Biopolymers as a Novel Strategy to Study Stem Cells during Wound‐Healing Processes
Authors: Grimaldi Annalisa , Banfi Serena , Vizioli Jacopo , Tettamanti Gianluca , Noonan Douglas M. , de Eguileor Magda
Published: March 2011

The biopolymer matrigel loaded with cytokine can be used for the recruitment in vivo of specific cell populations and as a vector for the preparation of cell cultures. Data demonstrate that the injection of the matrigel biopolymer supplemented with interleukin‐8 (IL‐8) in the leech Hirudo medicinalis can be used to purify cell populations showing the same morphofunctional and molecular mechanisms of specific populations of vertebrate hematopoietic precursor cells involved in tissue repair. These cells spontaneously differentiated into myofibroblasts. This approach highlights how the innovative use of a cytokine‐loaded biopolymer for an in vivo cell sorting method, applied to a simple invertebrate model, can be a tool for studying myofibroblast cell biology and its regulation, step by step.

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Enzyme‐Catalyzed Synthesis of a Novel Thermosensitive Polyester with Pendant Ketoprofen
Authors: Wang Hai‐Yang , Zhou Yu‐Jie , Wang Zao , Wang Na , Li Kun , Yu Xiao‐Qi
Published: March 2011

A novel thermosensitive polyester with pendant ketoprofen was synthesized by copolymerization of PEG 800 with 2‐ketoprofendimethylmalate using CAL‐B at 70 °C. The products were characterized by NMR spectra and GPC. The in vitro study demonstrated that the polyester could release ketoprofen in physiological conditions, which indicates that the polyester could be a promising prodrug.

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Ricci flow with hyperbolic warped product metrics
Authors: Ma Li , Xu Xingwang
Published: March 2011

In this short note, we show an example that the negative curvature is preserved in the deformation of hyperbolic warped product metrics under Ricci flow. It is showed that the flow converges to a flat metric in the sense of Cheeger‐Gromov as time going to infinity. © 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim
A Superhydrophobic to Superhydrophilic In Situ Wettability Switch of Microstructured Polypyrrole Surfaces
Authors: Chang Jean H. , Hunter Ian W.
Published: March 2011

We present an electrochemical layered system that allows for the fast, in situ wettability switch of microstructured PPy upon the application of an electric stimulus. We have eliminated the need for PPy to be immersed in an electrolyte to switch between wetting states, laying the groundwork for PPy to be used as a viable material in many applications, including microfluidics or smart textiles. The PPy surface was switched from the superhydrophobic state (contact angle = 159) to the superhydrophilic state (contact angle = 0) in 3 s. A wettability gradient was also created on a PPy surface using the layered system, causing a 3 µL droplet to travel approximately 2 mm in 0.8 s.

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Opto‐Mechanical Effect in Photoactive Nematic Side‐Chain Liquid‐Crystalline Elastomers
Authors: Sánchez‐Ferrer Antoni , Merekalov Alexey , Finkelmann Heino
Published: March 2011

The mechanical behaviour of monodomain nematic side‐chain liquid‐crystalline elastomers containing azoderivatives as pendant groups or crosslinkers has been studied under UV irradiation and in the darkness at different temperatures. From the evaluation of the opto‐mechanical experiments, the mechanical efficiency, kinetic rates, activation energies and the isomerization mechanism of the azocompounds in the liquid‐crystalline matrix could be determined, as well as the effect of the chemical constitution of the azobenzene derivatives and their role in the elastomeric network.

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Kinetics of polymerization of methyl methacrylate initiated by Ce(IV) ‐ disaccharide redox systems
Authors: Fernández M. D. , Guzmán G. M.
Published: March 2011

The polymerization of methyl methacrylate (MMA) initiated by ceric ammonium nitrate ‐ disaccharide redox systems has been studied in aqueous nitric acid at 30°C. The rate of polymerization and the rate of ceric ion disappearance were measured. The dependence of the rates on disaccharide and Ce(IV) concentrations have been evaluated. The reaction involves the formation of a complex between the metal ion and the reductants, whose decomposition gives rise to the initiating free radicals. The termination step takes place predominantly by mutual interaction between growing polymeric radicals.
Determination of kinetic constants for bulk polymerization of octyl acrylate at different temperatures
Authors: Katime Issa A. , Nuño T.
Published: March 2011

The bulk self‐initiated polymerization kinetics, assuming complete conversion of the octyl acrylate was determined by DTA in the temperature range 463‐493 K. Likewise, the overall activation energy, EA, and the polymerization enthalpies involved in the process have been calculated, as well as the overall rate constants and the reaction order.
Helical and sheet structures in the nylon 4 derivatives poly (α‐benzyl‐L‐glutamate) and poly‐(α‐methyl‐L‐glutamate)
Authors: Puiggali J. , MuñOz‐Guerra S. , Rodríguez‐Galán A. , Alegre C. , Subirana J. A.
Published: March 2011

We have synthesized and characterized the two stereoregular title compounds with a chemical formula:

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They form helical structures, similar to α‐helices (Form II), which are rather stable, in spite of the lower density of hydrogen bonds when compared with the standard α‐helix, found in proteins. We have determined the helical parameters of these structures by X‐ ray diffraction, and electron microscopy. Thin (10–40 nm) cylindrical threads are observed by the latter technique. The helix‐coil transition has been studied by proton NMR in the system chloroform/dichloroacetic acid. In the case of poly (α‐benzyl‐L‐glutamate) we have also found a sheet structure (Form I), similar to the extended sheets found in polyamides. The benzyl rings in the side chains appear to be stacked between such sheets.
The physical state of polycarbonate/hytrel blends
Authors: Gaztelumendi M. , Mondragón I. , Nazábal J.
Published: March 2011

Blends of bisphenol A polycarbonate (PC) with Hytrel (Hy), a thermoplastic elastomer, were melt mixed at different compositions and processing times. The blends thus obtained were progressively opaque as the Hy content of the blends increased due to the Hy crystallization, but showed a single Tg at all the blend contents. Torque of blending‐time and torque‐composition plots are discussed and related to the physical state of the blends.
Viscoelastic behaviour of poly (trimethylene terephthalate) and related polyesters
Authors: González César C. , Pereña José M. , Bello Antonio
Published: March 2011

Poly(oxytrimethyleneoxyterephthaloyl) (PTMT), poly(oxytrimethyleneoxytrimethyleneoxyterephthaloyl) (PTMTMT) and two copolymers derived from them have been studied by the use of a dynamic viscoelastometer. The four polymers show three relaxations α, β and γ in the temperature range between −150 and 200 °C. The α relaxation is the glass transition of the polymers, the β relaxation normally occurs in the vicinity of −70 °C, and the γ relaxation, usually overlapped by the β one, takes place at temperatures around −120 °C. The influence of the thermal history on the nature, location and intensity of the three relaxations is discussed.
Sub‐Tg storage of amorphous polymers
Authors: Zhou Y. Q. , Tong G. , Qi Z. N.
Published: March 2011

The sub‐T storage of PET(polyethylene terephthalate) and PEN(gpolyethylene naphthalate) has been investigated by means of TSC(thermally stimulated current) and DSC(differential scanning calorimetry). An apparent activation energy of sub‐T storage equal to one fourth of the activation energyg of glass transition has been obtained.
Physical interpretation of the rheological behaviour of amorphous polymers in the glass transition temperature range
Authors: Perez J. , Cavaille J. Y. , Jourdan C.
Published: March 2011

In a previous work, we developed, from physical basis, a theory of the non‐elastic deformation of amorphous polymers which is observed through the glass transition temperature. In this model, it is assumed that density fluctuations (or defects) exist in thermal equilibrium (TTg) or are frozen in (T< Tg). The application of a stress results in the nucleation of shear ‐ microdomains (smd) near the defects (anelasticity). A subsequent Irreversible expansion of shear ‐ loops might occur thanks to monomer diffusion which is shown to be dependent on (I) the defect concentration Cd and (II) on hierarchical correlation effects. The dynamic modulus G' and G' (and tanφ) are calculated as a function of parameters which can be known from Independent experimental ways and all have a precise physical meaning. The most Important parameter is the mechanical relaxation time τm linked to Cd; thus, all changes in the microstructure (i. e. Cd) imply a variation of the dynamic modulus.

The purpose of the present work is to make a comparison between the predictions of the model and experimental results obtained with polystyrene after different thermal histories.
Charge decay of corona‐charged electrets of amorphous polyethylene terephthalate
Authors: Belana J. , Pujal M. , Menéndez E.
Published: March 2011

During the formation of corona‐charged electrets of amorphous poly(ethylene terephthalate) at Tp between room temperature and 100°C, the charge injected from the electrodes to the sample is trapped from Tp to temperatures higher than 100°C. This fact determines that the measure of the initial charge of the electret is homocharge which is unstable with the time. The stored charge in the deep levels is the main cause for the internal field limiting the decrease of the heterocharge which finishes dominating in the decay process. The application of the thermally stimulated discharge to these electrets gives three relaxations whose behaviour has been analysed and has helped to interpret the decay of the charge.
Polypyrrole films formation by square waves in NaClO4 aqueous medium: Consecutive potential steps study
Authors: Fernándezotero T. , De Larreta E. , Tejada R.
Published: March 2011

The electrosynthesis of polypyrrole films was devised by consecutive potential steps. The time of each anodic and cathodic step, the number of consecutive steps, and the anodic potential of polarization influence the structure of the obtained polymer film, its adherence to the metal electrode and its electrochromic answer. Larger anodic polarization times (per step) give a polymer film formed by dendrites. Shorter anodic polarization times (per step) give smooth and adherent films. Darker colours were obtained when the number of polymerization potential steps increases.