bluuebunny/crossref_metadata_2025 huggingface dataset:
An effective interferon-gamma-mediated inhibition of hepatitis C virus replication by natural killer cells is associated with spontaneous clearance of acute hepatitis C in human immunodeficiency virus-positive patients
Authors: Kokordelis Pavlos , Krämer Benjamin , Körner Christian , Boesecke Christoph , Voigt Esther , Ingiliz Patrick , Glässner Andreas , Eisenhardt Marianne , Wolter Franziska , Kaczmarek Dominik , Nischalke Hans Dieter , Rockstroh Jürgen K. , Spengler Ulrich , Nattermann Jacob
Published: January 2014

Hepatitis C virus (HCV) coinfection is an increasing health problem in human immunodeficiency virus-positive (HIV+) individuals. However, a considerable proportion of HIV+ patients manage to overcome acute hepatitis C (AHC) spontaneously. In the present study, we analyzed the role of natural killer (NK) cells in modulating the course of AHC in HIV+ patients. Twenty-seven HIV+ patients with AHC (self-limited course: n = 10; chronic course: n = 17), 12 HIV+ patients with chronic hepatitis C (CHC), 8 HIV monoinfected individuals, and 12 healthy controls were studied. NK cells were phenotypically analyzed by flow cytometry. Interferon-gamma (IFN-γ) secretion, degranulation (CD107a), and anti-HCV (= inhibition of HCV replication) activity of NK subpopulations were analyzed using the HuH7A2HCVreplicon cell system. NK cell frequency did not differ significantly between HIV+ patients with chronic and self-limited course of AHC. However, we found NK cells from patients with self-limiting infection to be significantly more effective in inhibiting HCV replication in vitro than NK cells from patients developing CHC. Of note, antiviral NK cell activity showed no significant correlation with NK cell degranulation, but was positively correlated with IFN-γ secretion, and blocking experiments confirmed an important role for IFN-γ in NK cell-mediated inhibition of HCV replication. Accordingly, NK cells from patients that spontaneously cleared the virus displayed a stronger IFN-γ secretion than those developing chronic infection. Finally, we observed high expression of NKG2D and NKp46, respectively, to be associated with self-limiting course of aHCV. Accordingly, we found that blocking of these NK cell receptors significantly impaired antiviral NK cell activity. Conclusion: Our data suggest a strong IFN-γ-mediated antiviral NK cell response to be associated with a self-limited course of AHC in HIV+ patients. (HEPATOLOGY 2014;59:814–827)
Epigenetic reprogramming modulates malignant properties of human liver cancer
Authors: Raggi Chiara , Factor Valentina M. , Seo Daekwan , Holczbauer Agnes , Gillen Matthew C. , Marquardt Jens U. , Andersen Jesper B. , Durkin Marian , Thorgeirsson Snorri S.
Published: January 2014

Reversal of DNA hypermethylation and associated gene silencing is an emerging cancer therapy approach. Here we addressed the impact of epigenetic alterations and cellular context on functional and transcriptional reprogramming of hepatocellular carcinoma (HCC) cells. Our strategy employed a 3-day treatment of established and primary human HCC-derived cell lines grown as a monolayer at various cell densities with the DNMT1 inhibitor zebularine (ZEB) followed by a 3D culture to identify cells endowed with self-renewal potential. Differences in self-renewal, gene expression, tumorigenicity, and metastatic potential of spheres at generations G1-G5 were examined. Transient ZEB exposure produced differential cell density-dependent responses. In cells grown at low density, ZEB caused a remarkable increase in self-renewal and tumorigenicity associated with long-lasting gene expression changes characterized by a stable overexpression of cancer stem cell-related and key epithelial-mesenchymal transition genes. These effects persisted after restoration of DNMT1 expression. In contrast, at high cell density, ZEB caused a gradual decrease in self-renewal and tumorigenicty, and up-regulation of apoptosis- and differentiation-related genes. A permanent reduction of DNMT1 protein using short hairpin RNA (shRNA)-mediated DNMT1 silencing rendered HCC cells insensitive both to cell density and ZEB effects. Similarly, WRL68 and HepG2 hepatoblastoma cells expressing low DNMT1 basal levels also possessed a high self-renewal, irrespective of cell density or ZEB exposure. Spheres formed by low-density cells treated with ZEB or shDNMT1 displayed a high molecular similarity which was sustained through consecutive generations, confirming the essential role of DNMT1 depletion in the enhancement of cancer stem cell properties. Conclusion: These results identify DNA methylation as a key epigenetic regulatory mechanism determining the pool of cancer stem cells in liver cancer and possibly other solid tumors. (Hepatology 2014;59:2251–2262)
Human papillomavirus (HPV) genotypes in an Australian sample of anal cancers
Authors: Hillman Richard J. , Garland Suzanne M. , Gunathilake Manoji P.W. , Stevens Matthew , Kumaradevan Nirmala , Lemech Charlotte , Ward Robyn L. , Meagher Alan , McHugh Leo , Jin Fengyi , Carroll Susan , Goldstein David , Grulich Andrew E. , Tabrizi Sepehr N.
Published: January 2014

Human papillomavirus (HPV) causes most cases of anal cancers. In this study, we analyzed biopsy material from 112 patients with anal cancers in Australia for the presence of HPV DNA by the INNO LiPA HPV genotyping assay. There were 82% (92) males and 18% (20) females. The mean age at diagnosis was significantly (p = 0.006) younger for males (52.5 years) than females (66 years). HIV‐infected males were diagnosed at a much earlier mean age (48.2 years) than HIV negative (56.3 years) males (p = 0.05). HPV DNA was detected in 96.4% (108) of cases. HPV type 16 was the commonest, at 75% (81) of samples and being the sole genotype detected in 61% (66). Overall, 79% (85) of cases had at least one genotype targeted by the bivalent HPV (bHPV) vaccine, 90% (97) by the quadrivalent HPV (qHPV) vaccine and 96% (104) by the nonavalent HPV (nHPV) vaccine. The qHPV vaccine, which is now offered to all secondary school students in Australia, may prevent anal cancers in Australia. However, given the mean age of onset of this condition, the vaccine is unlikely to have a significant impact for several decades. Further research is necessary to prove additional protective effects of the nHPV vaccine.
Interaction of Integrin β4 With S1P Receptors in S1P‐ and HGF‐Induced Endothelial Barrier Enhancement
Authors: Ni Xiuqin , Epshtein Yulia , h  , Chen Weiguo , Zhou Tingting , Xie Lishi , Garcia Joe G.N. , Jacobson Jeffrey R.
Published: January 2014

We previously reported sphingosine 1‐phosphate (S1P) and hepatocyte growth factor (HGF) augment endothelial cell (EC) barrier function and attenuate murine acute lung inury (ALI). While the mechanisms underlying these effects are not fully understood, S1P and HGF both transactivate the S1P receptor, S1PR1 and integrin β4 (ITGB4) at membrane caveolin‐enriched microdomains (CEMs). In the current study, we investigated the roles of S1PR2 and S1PR3 in S1P/HGF‐mediated EC signaling and their associations with ITGB4. Our studies confirmed ITGB4 and S1PR2/3 are recruited to CEMs in human lung EC in response to either S1P (1 µM, 5 min) or HGF (25 ng/ml, 5 min). Co‐immunoprecipitation experiments identified an S1P/HGF‐mediated interaction of ITGB4 with both S1PR2 and S1PR3. We then employed an in situ proximity ligation assay (PLA) to confirm a direct ITGB4–S1PR3 association induced by S1P/HGF although a direct association was not detectable between S1PR2 and ITGB4. S1PR1 knockdown (siRNA), however, abrogated S1P/HGF‐induced ITGB4–S1PR2 associations while there was no effect on ITGB4–S1PR3 associations. Moreover, PLA confirmed a direct association between S1PR1 and S1PR2 induced by S1P and HGF. Finally, silencing of S1PR2 significantly attenuated S1P/HGF‐induced EC barrier enhancement as measured by transendothelial resistance while silencing of S1PR3 significantly augmented S1P/HGF‐induced barrier enhancement. These results confirm an important role for S1PR2 and S1PR3 in S1P/HGF‐mediated EC barrier responses that are associated with their complex formation with ITGB4. Our findings elucidate novel mechanisms of EC barrier regulation that may ultimately lead to new therapeutic targets for disorders characterized by increased vascular permeability including ALI. J. Cell. Biochem. 115: 1187–1195, 2014. © 2013 Wiley Periodicals, Inc.
MicroRNA‐190 Regulates Hypoxic Pulmonary Vasoconstriction by Targeting a Voltage‐Gated K+ Channel in Arterial Smooth Muscle Cells
Authors: Li Shan‐Shan , Ran Ya‐Juan , Zhang Dan‐Dan , Li Shu‐Zhen , Zhu Daling
Published: January 2014

Pulmonary arterial hypertension (PAH) is associated with sustained vasoconstriction, profound structural remodeling of vasculatures and alterations in Ca2+ homeostasis in arterial smooth muscle cells (SMCs), while the underlying mechanisms are still elusive. By regulating the expression of proteins, microRNAs (miRNAs) are known to play an important role in cell fates including differentiation, apoptosis and proliferation, and may be involved in the development of PAH. Based on our previous study, hypoxia produced a significant increase of the miR‐190 level in the pulmonary artery (PA), here, we used synthetic miR‐190 to mimic the increase in hypoxic conditions and showed evidence for the effects of miR‐190 on pulmonary arterial vasoconstriction and Ca2+ influx in arterial SMCs. Synthetic miR‐190 remarkably enhanced the vasoconstriction responses to phenylephrine (PE) and KCl. The voltage‐gated K+ channel subfamily member, Kcnq5, mRNA was shown to be a target for miR‐190. Meanwhile, miR‐190 antisense oligos can partially reverse the effects of miR‐190 on PASMCs and PAs. Therefore, these results suggest that miR‐190 appears to be a positive regulator of Ca2+ influx, and plays an important role in hypoxic pulmonary vascular constriction. J. Cell. Biochem. 115: 1196–1205, 2014. © 2013 Wiley Periodicals, Inc.
Vinculin Regulates Assembly of Talin: β3 Integrin Complexes
Authors: Nanda Suman Yadav , Hoang Thuy , Patel Priya , Zhang Hao
Published: January 2014

Vinculin is a talin‐binding protein that promotes integrin‐mediated cell adhesion, but the mechanisms are not understood. Because talin is a direct activator of integrins, we asked whether and how vinculin regulates the formation of integrin: talin complexes. We report that VD1 (aa 1‐258) and its talin‐binding mutant, VD1A50I, bind directly and equally to several β integrin cytoplasmic tails (βCT). Results from competition assays show that VD1, but not VD1A50I, inhibits the interaction of talin (Tn) and talin rod (TnR), but not talin head (TnH) with β3CT. The inhibition observed could be the result of VD1 binding to one or more of the 11 vinculin binding sites (VBSs) in the TnR domain. Our studies demonstrate that VD1 binding to amino acids 482‐911, a VBS rich region, in TnR perturbs the interaction of rod with β3CT. The integrin activation assays done using CHOA5 cells show that activated vinculin enhances αIIbβ3 integrin activation and that the effect is dependent on talin. The TnR domain however shows no integrin activation unlike TnH that shows enhanced integrin activation. The overall results indicate that activated vinculin promotes talin‐mediated integrin activation by binding to accessible VBSs in TnR and thus displacing the TnR from the β3 subunit. The study presented, defines a novel direct interaction of VD1 with β3CT and provides an attractive explanation for vinculin's ability to potentiate integrin‐mediated cell adhesion through directly binding to both TnR and the integrin cytoplasmic tail. J. Cell. Biochem. 115: 1206–1216, 2014. © 2013 Wiley Periodicals, Inc.
Endocan Elicits Severe Vascular Inflammatory Responses In Vitro and In Vivo
Authors: Lee Wonhwa , Ku Sae‐Kwang , Kim Shin‐Woo , Bae Jong‐Sup
Published: January 2014

Endocan is a proteoglycan secreted by endothelial cells under the control of inflammatory cytokines. The aim of this study was to evaluate the effects of endocan on proinflammatory responses and on septic mice and underlying mechanisms. Human umbilical vein endothelial cells (HUVECs) or mice were exposed to lipopolysaccharide (LPS) or endocan with or without neutralizing endocan antibody. Mice were subjected to cecal ligation and puncture (CLP) surgery with or without neutralizing endocan antibody. Endocan was highly released by LPS and it enhanced proinflammatory responses. In a CLP‐induced sepsis model, endocan was also highly released, but this release was prevented by administration of neutralizing endocan antibody. Circulating levels of endocan measured in patients admitted to the intensive care unit with sepsis were significantly elevated compared with control donors. Furthermore, the administration of endocan antibody reduced CLP‐induced sepsis mortality. This study shows endocan can elicit severe inflammatory responses and inhibiting endocan release offers a potential strategy for treating sepsis. J. Cell. Physiol. 229: 620–630, 2014. © 2013 Wiley Periodicals, Inc.
Microvesicle‐Shuttled miR‐130b Reduces Fat Deposition in Recipient Primary Cultured Porcine Adipocytes by Inhibiting PPAR‐γ Expression
Authors: Pan Shifeng , Yang Xiaojing , Jia Yimin , Li Runsheng , Zhao Ruqian
Published: January 2014

Obesity is a worldwide epidemic, and a risk factor for cardiovascular disease and type 2 diabetes. Consequently, the development of safe and effective anti‐obesity drugs is an area of ongoing clinical interest. MicroRNAs play a vital role in anti‐obesity by inhibiting the expression of genes involved in adipogenesis and lipogenesis. However, the clinical application of miRNAs has been limited by a lack of appropriate delivery systems. The discovery of microvesicles (MVs) has shed new light on the search for more efficient drug transport tools. In a previous study, we demonstrated that miRNA‐130b suppressed fat deposition by inhibiting PPAR‐γ expression. In order to demonstrate whether miRNA‐130b can be packaged into MVs and function as an endogenous form of miRNA‐130b in recipient cells, we transfected HeLa‐229 cells with plasmid to overexpress miRNA‐130b. This enabled HeLa‐229 cells to selectively package miRNA‐130b into MVs and actively secrete the miRNA‐130b enriched MVs into the culture media. We further verified that MVs enriched with miRNA‐130b contain elevated concentrations of Argonaute 2 and heat shock protein 90α which are known to protect the circulating miRNAs from degradation. Exposure of primary cultured porcine adipocytes to purified, miRNA‐130b‐enriched MVs resulted in a significant down‐regulation of PPAR‐γ expression which was associated with reduced adipogenesis and lipogenesis. Taken together, our results suggest that MVs may provide an effective transport systems for the deliver of miRNAs for therapeutic use. We also showed that MV‐shuttled miRNA‐130b inhibited adipogenesis and lipogenesis, and reduced fat deposition in recipient adipocytes by targeting PPAR‐γ. J. Cell. Physiol. 229: 631–639, 2014. © 2013 Wiley Periodicals, Inc.
Enzymatic and Regulatory Attributes of Trehalose‐6‐Phosphate Phosphatase from Candida utilis and its Role During Thermal Stress
Authors: Lahiri Sagar , Banerjee Shakri , Dutta Trina , Sengupta Shinjinee , Dey Sandip , Roy Rusha , Sengupta Devlina , Chattopadhyay Krishnananda , Ghosh Anil K.
Published: January 2014

Trehalose‐6‐phosphate phosphatase (TPP) catalyzes the final step in the biosynthesis of the anti‐stress sugar trehalose. An 82 kDa TPP enzyme was isolated from Candida utilis with 61% yield and 43‐fold purification. The protein sequence, determined by N‐terminal sequencing and MALDI‐TOF analysis, showed significant homology with known TPP sequences from related organisms. The full length gene sequence of TPP of C. utilis was identified using rapid amplification of cDNA ends‐PCR reaction (RACE‐PCR). The gene was cloned and expressed in Escherichia coli BL21. Recombinant TPP enzyme was isolated using affinity chromatography. CD spectroscopy and steady‐state fluorescence revealed that the structural and conformational aspects were identical in both native and recombinant forms. The biochemical properties of the two forms were also similar. Km was determined to be ~0.8 mM. Optimum temperature and pH were found to be 30 °C and 8.5, respectively. Activity was dependent on the presence of divalent cations and inhibited by metal chelators. Methylation‐mediated regulation of TPP enzyme and its effect on the overall survival of the organism under stress were investigated. The results indicated that enhancement of TPP activity by methylation at the Cysteine residues increased resistance of Candida cells against thermal stress. This work involves extensive investigations toward understanding the physico‐chemical properties of the first TPP enzyme from any yeast strain. The mechanism by which methylation regulates its activity has also been studied. A correlation between regulation of trehalose synthesis and survivability of the organism under thermal stress was established. J. Cell. Physiol. 229: 1245–1255, 2014. © 2014 Wiley Periodicals, Inc.
The Purα/Purβ Single‐Strand DNA‐Binding Proteins Attenuate Smooth‐Muscle Actin Gene Transactivation in Myofibroblasts
Authors: Hariharan Seethalakshmi , Kelm Robert J. , Strauch Arthur Roger
Published: January 2014

Expression of smooth muscle alpha‐actin (SMαA) is essential for myofibroblast‐mediated wound contraction following tissue injury. The Pur α/β and YB‐1 transcriptional repressors govern the DNA‐binding activity of serum response factor (SRF) and phosphorylated Smad3 (pSmad3) transcriptional activators during induction of SMαA gene expression in human pulmonary myofibroblasts. In quiescent fibroblasts, Pur α exhibited a novel function in enhancing stability of pre‐existing SRF complexes with SMαA core promoter DNA, whereas Pur β was more effective in disrupting SRF‐DNA interaction. Pur proteins were less efficient competitors of pre‐existing, core‐promoter complexes containing both SRF and pSmad3 in nuclear extracts from TGFβ1‐activated myofibroblasts. TGFβ1 signaling dissociated a SRF/Pur protein complex with concurrent formation of a transient pSmad3/MRTF‐A/Pur β complex during early phase myofibroblast differentiation. Pur β was replaced by Pur α in the pSmad3/MRTF‐A complex in mature myofibroblasts. Combining all three repressors potently inhibited SRF and pSmad3 binding to promoter DNA in quiescent fibroblasts and TGFβ1‐activated myofibroblasts, respectively. The results point to dynamic interplay between transcriptional activators and repressors in regulating SMαA gene output during myofibroblast differentiation. Therapeutic targeting of nucleoprotein complexes regulating the SMαA promoter may prevent excessive myofibroblast accumulation associated with chronic cardiopulmonary fibrosis and dysfunctional tissue remodeling. J. Cell. Physiol. 229: 1256–1271, 2014. © 2014 Wiley Periodicals, Inc.
Purification, characterization and partial sequence of a pro‐inflammatory lectin from seeds of Canavalia oxyphylla Standl. & L. O. Williams
Authors: Santiago Mayara Q. , Leitão Cintia C. F. , Pereira‐Junior Francisco N. , Pinto‐Junior Vanir R. , Osterne Vinicius J. S. , Lossio Claudia F. , Cajazeiras João B. , Silva Helton C. , Arruda Francisco V. S. , Pereira Livia P. , Assreuy Ana M. S. , Nascimento Kyria S. , Nagano Celso S. , Cavada Benildo S.
Published: January 2014

Recent studies have shown that lectins are promising tools for use in various biotechnological processes, as well as studies of various pathological mechanisms, isolation, and characterization of glycoconjugates and understanding the mechanisms underlying pathological mechanisms conditions, including the inflammatory response. This study aimed to purify, characterize physicochemically, and predict the biological activity of Canavalia oxyphylla lectin (CoxyL) in vitro and in vivo. CoxyL was purified by a single‐step affinity chromatography in Sephadex® G‐50 column. Sodium dodecyl sulfate polyacrylamide gel electrophoresis showed that the pure lectin consists of a major band of 30 kDa (α‐chain) and two minor components (β‐chain and γ‐chain) of 16 and 13 kDa, respectively. These data were further confirmed by electrospray ionization mass spectrometry, suggesting that CoxyL is a typical ConA‐like lectin. In comparison with the average molecular mass of α‐chain, the partial amino acid sequence obtained corresponds to approximately 45% of the total CoxyL sequence. CoxyL presented hemagglutinating activity that was specifically inhibited by monosaccharides (D‐glucose, D‐mannose, and α‐methyl‐D‐mannoside) and glycoproteins (ovalbumin and fetuin). Moreover, CoxyL was shown to be thermostable, exhibiting full hemagglutinating activity up to 60°C, and it was pH‐sensitive for 1 h, exhibiting maximal activity at pH 7.0. CoxyL caused toxicity to Artemia nauplii and induced paw edema in rats. This biological activity highlights the importance of lectins as important tools to better understand the mechanisms underlying inflammatory responses. Copyright © 2014 John Wiley & Sons, Ltd.
Does MRI Breast “Density” (Degree of Background Enhancement) Correlate With Mammographic Breast Density?
Authors: Hansen Nienke L. , Kuhl Christiane K. , Barabasch Alexandra , Strobel Kevin , Schrading Simone
Published: January 2014

Purpose

To investigate whether mammographic breast densities and the respective degree of MRI background enhancement would correlate. Mammographic breast density is coded to communicate how likely a cancer is obscured by parenchyma. Similarly, background enhancement in breast MRI could obscure enhancing cancer tissue.

Materials and Methods

A total of 468 women underwent standard full‐field digital mammography and dynamic contrast‐enhanced breast MRI in our institution. Mammographic breast density was scored according to the American College of Radiology‐classification; background enhancement in MRI was scored on a 4‐point scale from absent to severe. Breast “density classes” were retrospectively compared by analyzing the differences between scores for mammography and MRI. Statistical correlation was calculated using the Spearman coefficient.

Results

Scores matched in 19% of women (90/468) but differed in 81% (378/468). A deviation by 1 point was observed in 33% (157/468), by 2 points in 38% (179/468), by 3 in 9% (42/468). Scores for background enhancement were lower than mammographic scores in 371/468 (79.3%), equivalent in 90/468 (19.2%), and higher in 7/468 (1.5%).

Conclusion

Mammographic breast density does not correlate with the degree of background enhancement in MRI. In the majority of women, scores for background enhancement in MRI will be lower than the respective mammographic density scores. J. Magn. Reson. Imaging 2014;40:483–489. © 2014 Wiley Periodicals, Inc.
Towards new response criteria in neuroendocrine tumors: Which changes in MRI parameters are associated with longer progression‐free survival after radioembolization of liver metastases?
Authors: Ceelen Felix , Theisen Daniel , de Albéniz Xabier García , Auernhammer Christoph J. , Haug Alexander R. , D'Anastasi Melvin , Paprottka Philipp M. , Rist Carsten , Reiser Maximilian F. , Sommer Wieland H.
Published: January 2014

Purpose

To evaluate the association of therapy‐related changes in imaging parameters with progression‐free survival (PFS) of patients with unresectable liver metastases from neuroendocrine tumors (NETLMs).

Materials and Methods

Forty‐five radioembolized patients (median age: 62 years; range: 43–75) received a pre‐ and 3 months posttherapeutic magnetic resonance imaging (MRI) examination. The latter were evaluated for tumor size, arterial enhancement, and necrosis pattern. Influences of therapy‐related changes on PFS were analyzed. Statistical analysis included Student's t‐test, Wilcoxon test, Cox regression analysis, and Kaplan–Meier curves.

Results

The median percentage decrease in sum of diameters was 9.7% (range: 43.9% decrease to 15.4% increase). Twenty‐one patients (47%) showed increased necrosis. Three parameters were associated with significantly longer PFS: a decrease of diameter (hazard ratio [HR]: 0.206; 95% confidence interval [CI]: 0.058–0.725; P = 0.0139), a decrease in tumor arterial enhancement (HR: 0.143; 95% CI: 0.029–0.696; P = 0.0160), and an increase in necrosis after 3 months (HR: 0.321; 95% CI: 0.104–0.990; P = 0.0480). Multivariate analysis revealed that changes in diameter and arterial enhancement have complementary information and are associated independently with long PFS.

Conclusion

A decrease both in sum of diameters and arterial enhancement of metastases, as well as an increase in necrosis, are associated with significantly longer PFS after radioembolization. J. Magn. Reson. Imaging 2015;41:361–368.© 2013 Wiley Periodicals, Inc.
Influence of APOE genotype and the presence of Alzheimer's pathology on synaptic membrane lipids of human brains
Authors: Oikawa Naoto , Hatsuta Hiroyuki , Murayama Shigeo , Suzuki Akemi , Yanagisawa Katsuhiko
Published: January 2014

The APOE genotype is the major risk factor for Alzheimer's disease (AD); however, it remains unclarified how the ε4 allele accelerates whereas the ε2 allele suppresses AD development, compared with the more common ε3 allele. On the basis of the previous finding that the assembly of the amyloid‐β protein (Aβ) into fibrils in the brain, an early and invariable pathological feature of AD, depends on the lipid environment, we determined the levels of synaptic membrane lipids in aged individuals of different APOE genotypes. In the comparison between amyloid‐free ε2/ε3 and ε3/ε3 brains, the presence of the ε2 allele significantly decreased the level of cholesterol. Alternatively, in the comparison among ε3/ε3 brains, the presence of AD pathology substantially decreased the levels of cholesterol. This study suggests that the ε2 allele suppresses the initiation of AD development by lowering the cholesterol levels in synaptic membranes. © 2014 Wiley Periodicals, Inc.
Palmitic acid affects proliferation and differentiation of neural stem cells in vitro
Authors: Wang Zhen , Liu Dexiang , Zhang Qun , Wang Jianmei , Zhan Jingmin , Xian Xiuying , Du Zhaoxia , Wang Xueer , Hao Aijun
Published: January 2014

High‐lipid diet composed of saturated fatty acids (SFAs) has significant detrimental effects on brain homeostasis, and deleterious effects of SFAs on various cells have been well documented. However, the effects of SFAs on neural stem Cells (NSCs) function have not been fully explored. The aim of this study was to determine whether palmitic acid (PA) affected the proliferation and differentiation of murine‐derived NSCs. The results showed that PA dose dependently suppressed viability of NSCs and was cytotoxic at high concentrations. The toxic levels of PA inhibited the proliferation of NSCs as shown by reduced bromodeoxyuridine labeling of NSCs, which is correlated with reactive oxygen species generation. Pretreatment of the cells with the antioxidant N‐acetyl‐L‐cysteine inhibitor significantly attenuated the effects of PA on the proliferation of NSCs. Furthermore, nontoxic levels of PA promoted astrocytogenesis in the differentiated NSCs, associated with Stat3 activation and altered expression of serial of basic helix–loop–helix transcription factor genes. Altogether, our data have demonstrated that PA has a significant impact on proliferation and differentiation of NSCs in vitro and may be useful for elucidating the role of SFAs in regulating NSCs fate in physiological and pathological settings. © 2014 Wiley Periodicals, Inc.
Nonredundant function of two highly homologous octopamine receptors in food‐deprivation‐mediated signaling in Caenorhabditis elegans
Authors: Yoshida Midori , Oami Eitaro , Wang Min , Ishiura Shoichi , Suo Satoshi
Published: January 2014

It is common for neurotransmitters to possess multiple receptors that couple to the same intracellular signaling molecules. This study analyzes two highly homologous G‐protein‐coupled octopamine receptors using the model animal Caenorhabditis elegans. In C. elegans, the amine neurotransmitter octopamine induces activation of cAMP response element‐binding protein (CREB) in the cholinergic SIA neurons in the absence of food through activation of the Gq‐coupled octopamine receptor SER‐3 in these neurons. We also analyzed another Gq‐coupled octopamine receptor, SER‐6, that is highly homologous to SER‐3. As seen in ser‐3 deletion mutants, octopamine‐ and food‐deprivation‐mediated CREB activation was decreased in ser‐6 deletion mutants compared with wild‐type animals, suggesting that both SER‐3 and SER‐6 are required for signal transduction. Cell‐specific expression of SER‐6 in the SIA neurons was sufficient to restore CREB activation in the ser‐6 mutants, indicating that SER‐6, like SER‐3, functions in these neurons. Taken together, these results demonstrate that two similar G‐protein‐coupled receptors, SER‐3 and SER‐6, function in the same cells in a nonredundant manner. © 2014 Wiley Periodicals, Inc.
Decomposition of in vivo spatially offset Raman spectroscopy data using multivariate analysis techniques
Authors: Buckley Kevin , Kerns Jemma G. , Parker Anthony W. , Goodship Allen E. , Matousek Pavel
Published: January 2014

The decomposition of spatially offset Raman spectra for complex multilayer systems, such as biological tissues, requires advanced techniques such as multivariate analyses. Often, in such situations, the decomposition methods can reach their limits of accuracy well before the limits imposed by signal‐to‐noise ratios. Consequently, more effective reconstruction methods could yield more accurate results with the same data set. In this study we process spatially offset Raman spectroscopy (SORS) data with three different multivariate techniques (band‐target entropy minimization (BTEM), multivariate curve resolution and parallel factor analysis (PARAFAC)) and compare their performance when analysing a spectrally challenging plastic model system and an even more challenging problem, the analysis of human bone transcutaneously in vivo. For the in vivo measurements, PARAFAC's requirement of multidimensional orthogonal data is addressed by recording SORS spectra both at different spatial offsets and at different anatomical points, the latter providing added dimensionality through the variation of skin/soft tissue thickness.

The BTEM and PARAFAC methods performed the best on the plastic system with the BTEM more faithfully reconstructing the major Raman bands and PARAFAC the smaller more heavily overlapped features. All three methods succeeded in reconstructing the bone spectrum from the transcutaneous data and gave good figures for the phosphate‐to‐carbonate ratio (within 2% of excised human tibia bone); the PARAFAC gave the most accurate figure for the mineral‐to‐collagen ratio (20% less than excised human tibia bone).

Previous studies of excised bones have shown that certain bone diseases (such as osteoarthritis, osteoporosis and osteogenesis imperfecta) are accompanied by compositional abnormalities that can be detected with Raman spectroscopy, the utility of a technique which could reconstruct bone spectra accurately is manifest. The results have relevance on the use of SORS in general. © 2014 Crown copyright. Journal of Raman Spectroscopy published by John Wiley & Sons, Ltd.
In‐situ Raman spectroscopy of current‐carrying graphene microbridge
Authors: Choi Minkyung , Son Jangyup , Choi Heechae , Shin Hyun‐Joon , Lee Sangho , Kim Sanghoon , Lee Soogil , Kim Seungchul , Lee Kwang‐Ryeol , Kim Sang Jin , Hong Byung Hee , Hong Jongill , Yang In‐Sang
Published: January 2014

In‐situ Raman spectroscopy was performed on chemical vapor deposited graphene microbridge (3 μm × 80 μm) under electrical current density up to 2.58 × 108 A/cm2 in ambient conditions. We found that both the G and the G′ peak of the Raman spectra do not restore back to the initial values at zero current, but to slightly higher values after switching off the current through the microbridge. The up‐shift of the G peak and the G′ peak, after switching off the electrical current, is believed to be due to p‐doping by oxygen adsorption, which is confirmed by scanning photoemission microscopy. Both C–O and C=O bond components in the C1s spectra from the microbridge were found to be significantly increased after high electrical current density was flown. The C=O bond is likely the main source of the p‐doping according to our density functional theory calculation of the electronic structure. Copyright © 2014 John Wiley & Sons, Ltd.
A novel diazoresin/poly(N‐vinyl aminobutyric acid) covalent capillary coating for the analysis of proteins by capillary electrophoresis
Authors: Yu Bing , Jiao Mingming , Cong Hailin , Shu Xi , Yang Shujing
Published: January 2014

A novel method for the preparation of covalently linked capillary coatings of poly(N‐vinyl aminobutyric acid) (PVAA) obtained from hydrolyzed polyvinylpyrrolidone was demonstrated using photosensitive diazoresin (DR) as a coupling agent. A layer‐by‐layer self‐assembled film of DR and PVAA based on ionic bonding was first fabricated on the inner wall of capillary, then ionic bonding was converted into covalent bonding after treatment with UV light through a unique photochemical reaction of DR. The covalently bonded coatings suppressed protein adsorption on the inner surface of the capillary, and thus a baseline separation of lysozyme, cytochrome c, BSA, amyloglucosidase, and myoglobin was achieved using CE. Compared with bare capillary or noncovalently bonded DR/PVAA coatings, the covalently linked DR/PVAA capillary coatings not only improved the CE separation performance for proteins, but also exhibited good stability and repeatability. Due to the replacement of the highly toxic and moisture‐sensitive silane coupling agent by DR in the covalent coating preparation, this method may provide a green and easy way to make covalently coated capillaries for CE.
Separation and purification of steroidal saponins from Paris polyphylla by microwave‐assisted extraction coupled with countercurrent chromatography using evaporative light scattering detection
Authors: Xiao Xiao‐Hua , Yuan Zhi‐Quan , Li Gong‐Ke
Published: January 2014

A method of microwave‐assisted extraction coupled with countercurrent chromatography using evaporative light scattering detection was successfully developed for the separation and purification of steroidal saponins from Paris polyphylla. The main extraction conditions including microwave power, liquid/solid ratio, irradiation time, and extraction temperature were optimized using an orthogonal array design method. A suitable two‐phase solvent system consisting of n‐heptane/n‐butanol/acetonitrile/water (10:19:6:20, v/v/v/v) was employed in the separation and purification of the extracts of P. polyphylla. A total of 7.1 mg polyphyllin VII, 4.3 mg gracillin, 9.2 mg dioscin, and 10.2 mg polyphyllin I were obtained from 1.5 g P. polyphylla in less than 300 min, the purities of which determined by HPLC were 96.7, 97.3, 98.7, and 98.6%, respectively. The identification and characterization of these compounds were performed by LC–ESI‐MS and 1H NMR spectroscopy. The results demonstrated that the proposed method is feasible, economical and efficient for the extraction, separation and purification of effective compounds from natural products.
The Effect of Polyglycerol Sulfate Branching On Inflammatory Processes
Authors: Paulus Florian , Schulze Ronny , Steinhilber Dirk , Zieringer Maximilian , Steinke Ingo , Welker Pia , Licha Kai , Wedepohl Stefanie , Dernedde Jens , Haag Rainer
Published: January 2014

In this study, the extent to which the scaffold architecture of polyglycerol sulfates affects inflammatory processes and hemocompatibility is investigated. Competitive L‐selectin binding assays, cellular uptake studies, and blood compatibility readouts are done to evaluate distinct biological properties. Fully glycerol based hyperbranched polyglycerol architectures are obtained by either homopolymerization of glycidol (60% branching) or a new copolymerization strategy of glycidol with ethoxyethyl glycidyl ether. Two polyglycerols with 24 and 42% degree of branching (DB) are synthesized by using different monomer feed ratios. A perfectly branched polyglycerol dendrimer is synthesized according to an iterative two‐step protocol based on allylation of the alcohol and subsequent catalytic dihydroxylation. All the polyglycerol sulfates are synthesized with a comparable molecular weight and degree of sulfation. The DB make the different polymer conjugates perform different ways. The optimal DB is 60% in all biological assays.
Improvement in mechanical properties of grafted polylactic acid composite fibers via hot melt extrusion
Authors: Gunning Michael A. , Geever Luke M. , Killion John A. , Lyons John G. , Higginbotham Clement L.
Published: January 2014

The aim of this study was to develop fiber reinforced polylactic acid (PLA) composites via twin screw extrusion with the addition of a compatibilizer. Initial studies were performed to establish the optimum initiator percentage in terms of grafting efficiency between PLA and maleic anhydride (MA). Results show that PLA MA 7 obtained the highest level of grafting efficiency. Subsequent viscometric titration analysis on the compatibilized and uncompatibilized PLA composites showed an increase in the interfacial adhesion for the compatibilized PLA composites. Tensile and flexural properties also confirmed this increase in interfacial adhesion for the compatibilized composites, where the mechanical properties improved considerably, compared with virgin PLA and uncompatibilized composites. Results showed that the mechanical properties increase as PLA‐g‐MA loading increased. Finally, the rate of compostability of compatibilized composites decreased with the addition of PLA‐g‐MA. This was attributed to a lack of water absorption due to the bonding of hydroxyl groups on the fibers surface with MA. POLYM. COMPOS., 35:1792–1797, 2014. © 2014 Society of Plastics Engineers
Mechanical and thermal properties of exfoliated graphite nanoplatelets reinforced polyethylene terephthalate/polypropylene composites
Authors: Inuwa Ibrahim Mohammed , Hassan Azman , Samsudin Sani Amril , Mohamad Kassim Mohamad Haafiz , Jawaid Mohamad
Published: January 2014

Exfoliated graphite nanoplatelets (GNP) reinforced composites materials based on blend of poly(ethylene terephthalate) (PET) and polypropylene (PP) were prepared by melt extrusion followed by injection molding. 10 parts per hundred resin (phr) styrene‐ethylene‐butylene‐styrene‐g‐maleic anhydride was added to the base formulation PET/PP (70/30) as a compatibilizer. PET/PP/GNP composites 0–5 phr were prepared and characterized using field emission scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, and Fourier transform infrared (FTIR) spectroscopy analysis. The morphological studies revealed a homogenous dispersion of GNPs in PET/PP blends up to 3 phr loading after which agglomeration occurred. Flexural strength was enhanced by 80% at 3 phr GNPs loading which was the highest value obtained. Interestingly, the highest value for the impact strength was also recorded at 3 phr loading. The thermal stability of the composites were generally improved at all filler loading with the highest at 3 phr. From the overall results, it is clear that the optimum concentration of GNPs in the PET/PP/GNP system in terms of both mechanical and thermal properties was 3 phr loading. Although, the mechanical and thermal properties of the composites were improved, the FTIR analysis did not reveal any chemical interaction between GNP and the polymer matrix. POLYM. COMPOS., 35:2029–2035, 2014. © 2014 Society of Plastics Engineers
Functionalizing carbon nanotubes by grafting cyclotriphosphazene derivative to improve both mechanical strength and flame retardancy
Authors: Ma Haiyun , Zhao Lici , Liu Jiawei , Wang Jun , Xu Jianzhong
Published: January 2014

An intumescent flame‐retardant, hex(4‐carboxylphenoxy) cyclotriphosphazene (HCPCP) was synthesized and covalently grafted on to the surface of multiwalled carbon nanotubes (MWNTs) to obtain MWNT‐HCPCP. MWNT/epoxy resin (EP) and MWNT‐HCPCP/ EP nanocomposites were prepared via thermal curing. Transmission electron microscopy results showed that a core–shell structure with MWNTs as the hard core and HCPCP as the soft shell were formed after HCPCP (10 wt%) were attached to the MWNTs. The results of flammability tests showed an increased limited oxygen index value for MWNT‐HCPCP/EP nanocomposites. The mechanical properties including tensile strength and elongation were both dramatically improved due to the better dispersion of MWNT‐HCPCP in the EP matrix. The grafting of HCPCP can improve both the dispersion of nanotubes in polymer matrix and flame retardancy of the nanocomposites. POLYM. COMPOS., 35:2187–2193, 2014. © 2014 Society of Plastics Engineers
Characterizations of basalt unsaturated polyester laminates under static three‐point bending and low‐velocity impact loadings
Authors: Gideon Rotich K. , Hu Hangjun , Wambua Paul , Gu Bohong
Published: January 2014

This paper reports the responses of basalt unsaturated polyester laminates under static three‐point bending loading and low‐velocity impact. Three kinds of composite materials, unidirectional (0°), cross‐ply (0°/90°) and woven laminates were considered. The laminates were fabricated by layup process and hot pressed under pressure. Static three‐point bending tests and low‐velocity impact tests were conducted to obtain the force–deflection, force–time, deflection–time, velocity–time, and energy–time curves. The results showed that unidirectional (0°) laminates carried more load during static loading, but in the event of dynamic loading, cross‐ply, and woven laminates were more superior. It was observed that the failure of 0° laminates was along the fiber direction while for cross‐ply and woven, the damage was localized, around the impacted locations. From the different combinations of unidirectional (0°), cross‐ply (0°/90°) and woven lamina, the impact behaviors could be optimized with the lowest area density. POLYM. COMPOS., 35:2203–2213, 2014. © 2014 Society of Plastics Engineers
Proteomic analysis of human substantia nigra identifies novel candidates involved in Parkinson's disease pathogenesis
Authors: Licker Virginie , Turck Natacha , Kövari Enikö , Burkhardt Karim , Côte Mélanie , Surini‐Demiri Maria , Lobrinus Johannes A. , Sanchez Jean‐Charles , Burkhard Pierre R.
Published: January 2014

Parkinson's disease (PD) pathology spreads throughout the brain following a region‐specific process predominantly affecting the substantia nigra (SN) pars compacta. SN exhibits a progressive loss of dopaminergic neurons responsible for the major cardinal motor symptoms, along with the occurrence of Lewy bodies in the surviving neurons. To gain new insights into the underlying pathogenic mechanisms in PD, we studied postmortem nigral tissues dissected from pathologically confirmed PD cases (n = 5) and neurologically intact controls (n = 8). Using a high‐throughput shotgun proteomic strategy, we simultaneously identified 1795 proteins with concomitant quantitative data. To date, this represents the most extensive catalog of nigral proteins. Of them, 204 proteins displayed significant expression level changes in PD patients versus controls. These were involved in novel or known pathogenic processes including mitochondrial dysfunction, oxidative stress, or cytoskeleton impairment. We further characterized four candidates that might be relevant to PD pathogenesis. We confirmed the differential expression of ferritin‐L and seipin by Western blot and demonstrated the neuronal localization of gamma glutamyl hydrolase and nebulette by immunohistochemistry. Our preliminary findings suggest a role for nebulette overexpression in PD neurodegeneration, through mechanisms that may involve cytoskeleton dynamics disruption. All MS data have been deposited in the ProteomeXchange with identifier PXD000427 (http://proteomecentral.proteomexchange.org/dataset/PXD000427).
The role of O‐GlcNAc signaling in the pathogenesis of diabetic retinopathy
Authors: Semba Richard D. , Huang Hu , Lutty Gerard A. , Van Eyk Jennifer E. , Hart Gerald W.
Published: January 2014

Diabetic retinopathy is a leading cause of blindness worldwide. Despite laser and surgical treatments, antiangiogenic and other therapies, and strict metabolic control, many patients progress to visual impairment and blindness. New insights are needed into the pathophysiology of diabetic retinopathy in order to develop new methods to improve the detection and treatment of disease and the prevention of blindness. Hyperglycemia and diabetes result in increased flux through the hexosamine biosynthetic pathway, which, in turn, results in increased PTM of Ser/Thr residues of proteins by O‐linked β‐N‐acetylglucosamine (O‐GlcNAc). O‐GlcNAcylation is involved in regulation of many nuclear and cytoplasmic proteins in a manner similar to protein phosphorylation. Altered O‐GlcNAc signaling has been implicated in the pathogenesis of diabetes and may play an important role in the pathogenesis of diabetic retinopathy. The goal of this review is to summarize the biology of the hexosamine biosynthesis pathway and O‐GlcNAc signaling, to present the current evidence for the role of O‐GlcNAc signaling in diabetes and diabetic retinopathy, and to discuss future directions for research on O‐GlcNAc in the pathogenesis of diabetic retinopathy.
Application of proteomic technologies to discover and identify biomarkers for periodontal diseases in gingival crevicular fluid: A review
Authors: Tsuchida Sachio , Satoh Mamoru , Sogawa Kazuyuki , Kawashima Yusuke , Kado Sayaka , Ishige Takayuki , Beppu Minako , Sawai Setsu , Nishimura Motoi , Kodera Yoshio , Matsushita Kazuyuki , Nomura Fumio
Published: January 2014

Periodontal disease is a bacterial infection that destroys the gingiva and surrounding tissues of the oral cavity. In recent years, studies have shown a definite association between periodontal disease and other inflammatory conditions of the body. High‐throughput analysis of proteins has become possible with the development of MS technology. This breakthrough in proteome technology enables comparative studies of comprehensive protein expression and identification of protein. In case of periodontal disease, proteome analysis using 2DE, as well as gel‐free methods, has been reported. As a fluid lying in close proximity to periodontal tissue, the gingival crevicular fluid (GCF) is the principal target in the search for biomarkers of periodontal disease, because its protein composition may reflect the disease pathophysiology. Biochemical marker analysis of GCF is effective for objective diagnosis in the early and advanced stages of periodontal disease. Increasing numbers of recent reports have provided evidence that the proteomic approach is a promising tool for the discovery and identification of biochemical markers of periodontal disease. This search is of continuing interest in the field of experimental and clinical periodontal disease research. In this article, we summarize recent comprehensive proteomic studies aimed at discovering and identifying biomarkers of periodontal disease in GCF.
Position‐specific induction of ectopic limbs in non‐regenerating blastemas on axolotl forelimbs
Authors: McCusker Catherine , Lehrberg Jeffrey , Gardiner David
Published: January 2014

Ectopic retinoic acid (RA) has been hypothesized to reprogram the positional identity of cells in developing and regenerating limbs to a single positional value corresponding to the posterior‐ventral‐proximal (PVPr) position on the limb. We tested this hypothesis by using RA to reprogram the information of blastema cells that were induced to form at different positions around the limb circumference. We observed that RA treatment of blastemas in anterior and dorsal locations, but not posterior and ventral locations, resulted in the induction of complete ectopic limbs. These position‐specific differences in limb induction are probably due to differences in the positional disparity between the RA‐reprogrammed blastema cells and the cells at the periphery of the wound. These observations are consistent with the hypothesis that RA treatment reprograms the information in blastema cells to the PVPr position on the limb, since anterior and dorsal positions have the largest disparity and posterior and ventral have the smallest disparity from the PVPr identity.