bluuebunny/crossref_metadata_2025 huggingface dataset:
Investigation of a DNA‐Based Biosensor with Chitosan‐Carbon Nanotubes Interface by Cyclic and Elimination Voltammetry
Authors: Galandova Julia , Trnkova Libuse , Mikelova Radka , Labuda Jan
Published: January 2009

The paper presents a disposable DNA biosensor based on a composite of multiwalled carbon nanotubes (MWCNT) in chitosan (CHIT) used as an interface at the screen printed carbon electrode (SPCE). Double stranded herring sperm DNA was immobilized over the MWCNT‐CHIT layer. The response of the modified SPCE with and without DNA was characterized using the redox probe [Fe(CN)6]3−/4− in the mode of cyclic voltammetry and elimination voltammetry with linear scan (EVLS), which enables the elimination of selected partial voltammetric currents contributing to the total current. The elimination functions providing a significant increase in the voltammetric current sensitivity and improving the peak resolution enable to indicate an adsorbed state of depolarizers, to discover hidden electrode processes, and to determine their nature. The SPCE surface modification was evaluated using (a) the charge transfer coefficient α of the redox probe calculated from the Tafel plot analysis (TPA) and EVLS and (b) the polarization resistance RP for both cathodic and anodic processes.
Bismuth‐Coated Screen‐Printed Microband Electrodes for On‐Field Labile Cadmium Determination
Authors: Zaouak Olivier , Authier Laurent , Cugnet Cyril , Castetbon Alain , Potin‐Gautier Martine
Published: January 2009

Performances of a screen‐printed microband electrode prepared by ex situ bismuth deposition are reported. According to the low bismuth toxicity, this electrode represents an environmentally friendly alternative to mercury modified sensors, particularly for on‐field measurements. The electrochemical behaviour of the microband electrode has been studied and is in agreement with microelectrode theory before and after bismuth modification. Sensitive cadmium analysis achieved in nondeaerated and unstirred solutions leads to a detection limit of 1.3 μg L−1 using SWASV for 120 s deposition time. This sensor has been successfully applied to a nontreated river water sample.
Zinc hydroxystannate‐coated metal hydroxides as flame retardant and smoke suppression for flexible poly vinyl chloride
Authors: Qu Hongqiang , Wu Weihong , Xie Jixing , Xu Jianzhong
Published: January 2009

Zinc hydroxystannate (ZHS)‐coated metal hydroxides were prepared. The effects of ZHS‐coated metal hydroxides on flame retardancy and smoke suppression of flexible poly vinyl chloride were studied by means of the limiting oxygen index, smoke density rating and the char yield test. The mechanism was investigated by thermogravimerty (TG), differential thermal analysis, and differential TG analysis and scanning electron microscopy. The results showed that ZHS‐coated metal hydroxides are more effective flame retardant and smoke suppressant than metal hydroxides, and it appears that tin compound may exert its action in both the condensed and vapor phases, but mainly in condensed phases as a Lewis acid. Copyright © 2009 John Wiley & Sons, Ltd.
Alpha fetoprotein is a novel protein‐binding partner for caspase‐3 and blocks the apoptotic signaling pathway in human hepatoma cells
Authors: Li Mengsen , Li Hui , Li Chaoying , Zhou Sheng , Guo Liyuan , Liu Han , Jiang Wei , Liu Xinhua , Li Pingfeng , McNutt Michael A. , Li Gang
Published: January 2009

Although there is increasing evidence that alpha fetoprotein (AFP) may function as regulatory factor in the growth of tumor cells, the precise mechanism is still unclear. In the current study, we investigated the role of the cytoplasmic AFP in caspase‐3‐mediated signaling of apoptosis. Our results showed that low doses of TNF‐related apoptosis‐inducing ligand (TRAIL) elevated the activity of caspase‐8, but not caspase‐3. Caspase‐3 colocalized and interacted with AFP in the cytoplasm of Bel 7402 cells, and translocated into nuclei in association with the occurrence of apoptosis while cells were under cotreatment with all‐trans retinoic acid (ATRA) or TRAIL. AFP was able to form complexes with caspase‐3 and block onward transmission of signaling from caspase‐8. Knockdown of AFP increased the sensitivity of Bel 7402 cells to TRAIL, and thereby, triggered caspase‐3 signaling. No intermolecule interaction occurred between AFP and caspase‐8, nor was caspase‐8 activity altered after AFP knockdown, demonstrating the selectivity of AFP in interfering with the apoptotic signaling pathway. The effect of AFP on caspase‐3 was further confirmed by transfection of the AFP gene into HLE cells (AFP negative). We conclude that ATRA or TRAIL resistance in AFP producing hepatoma is at least, in part, attributable to the high level of the cytoplasmic AFP. Therefore, it is possible that the combination of AFP gene silencing together with ATRA/TRAIL cotreatment will benefit the enhancement of the chemotherapeutic efficiency of these agents on tumors. © 2009 UICC
Nmi (N‐Myc interactor) inhibits Wnt/β‐catenin signaling and retards tumor growth
Authors: Fillmore Rebecca A. , Mitra Aparna , Xi Yaguang , Ju Jingfang , Scammell Jonathan , Shevde Lalita A. , Samant Rajeev S.
Published: January 2009

We found that the expression levels of N‐Myc interactor (Nmi) were low in aggressive breast cancer cell lines when compared with less aggressive cell lines. However, the lower levels in the aggressive lines were inducible by interferon‐γ (IFN‐γ). Because Nmi has been reported to be a transcription cofactor that augments IFN‐γ induced transcription activity, we decided to test whether Nmi regulates expression of Dkk1, which is also inducible by IFN‐γ. We established stable clones constitutively expressing Nmi in MDA‐MB‐231 (breast) and MDA‐MB‐435 (melanoma) cell lines. Dkk1 was significantly up‐regulated in the Nmi expressing clones concurrent with reduced levels of the critical transcription cofactor of Wnt pathway, β‐catenin. Treatment of the Nmi expressors with blocking antibody to Dkk1 restored β‐catenin protein levels. c‐Myc is a known downstream target of activated β‐catenin signaling. Treatment of Nmi expressors with the proteosome inhibitor MG132, resulted in elevated β‐catenin levels with concomitant elevation of c‐Myc levels. Our functional studies showed that constitutive expression of Nmi reduced the ability of tumor cells for the invasion, anchorage independent growth and tumor growth in vivo. Collectively, the data suggest that overexpression of Nmi inhibits the Wnt/β‐catenin signaling via up‐regulation of Dkk1 and retards tumor growth. © 2009 UICC
Proteomic and phosphoproteomic alterations in benign, premalignant and tumor human breast epithelial cells and xenograft lesions: Biomarkers of progression
Authors: Kim So Hee , Miller Fred R. , Tait Larry , Zheng Jie , Novak Raymond F.
Published: January 2009

The MCF10A human breast epithelial cell lineage includes the benign MCF10A cells, premalignant cells (MCF10AT, MCF10ATG3B) and malignant MCF10CA1a tumor cells. The premalignant and tumor cells recapitulate the progressive alterations associated with the temporal development of PBD and carcinoma. Ras protein levels were elevated by 6.9‐, 22.4‐ and 32.2‐fold in 10AT, 10ATG3B and 10CA1a cells, respectively, relative to 10A cells. K‐Ras was not detected, N‐Ras levels were unchanged; Rac and Rho levels increased in 10CA1a tumor cells. Phospho‐phosphatidylinositol 3‐kinase, phosphoinositide‐dependent protein kinase 1 (PDK1), phospho‐PDK1, phospho‐eukaryotic translation initiation factor 4E (eIF4E) and phospho‐eukaryotic initiation factor 4E binding protein 1 (4E‐BP1) levels progressively increased in the cell lineage, with the greatest increase monitored in 10CA1a tumor cells. Phospho Ser 473 and Thr 408 Akt levels increased 10.2‐ and 136‐fold in 10CA1a cells, respectively, relative to 10A cells. Phospho‐p70S6 kinase (p70S6K) increased >2‐fold in 10CA1a cells, relative to 10A cells. Immunohistochemistry confirmed Ras, phospho‐Akt and phospho‐p70S6K (Thr 421/ Ser 424) expression in lesions arising from premalignant and tumor cells. FOXO 1, phospho‐FOXO 1 and phospho‐FOXO 4 were significantly elevated in 10ATG3B premalignant and 10CA1a tumor cells. Phospho‐FOXO 3a was progressively elevated, with the greatest levels detected in 10CA1a tumor cells. Immunohistochemistry revealed that phospho‐FOXO 1, 3a and 4 staining was less in benign lesions, but elevated in advanced 10ATG3B and malignant 10CA1a lesions, showing a correspondence between the cells and lesions. Hence, phospho‐Akt and phospho‐FOXO 1, 3a and 4 merit consideration as biomarkers of tumorigenic risk from hyperplastic breast tissue. © 2009 UICC
PTD4‐apoptin protein therapy inhibits tumor growth in vivo
Authors: Sun Jun , Yan Ying , Wang Xiao‐Ting , Liu Xiao‐Wen , Peng Dong‐Jun , Wang Min , Tian Jun , Zong Yi‐Qiang , Zhang Ying‐Hui , Noteborn Mathieu H.M. , Qu Shen
Published: January 2009

Apoptin protein harbors tumor‐selective cell death activity, which makes it a potential anticancer therapy candidate. This study reports an apoptin therapy approach based on protein transduction domain 4 (PTD4)‐mediated transduction of recombinant apoptin protein. In vitro, the PTD4‐apoptin fusion protein is located in the nucleus and induces cell death in, e.g., human hepatocarcinoma HepG2 cells. In normal human L‐02 hepatocytes, PTD4‐apoptin protein retained mainly cytoplasmic and did not induce detectable levels of cell death, illustrating that the PTD4 domain does not affect apoptin's tumor‐selective characteristics. In vivo, liver, cervix and gastric carcinoma xenografts treated with PTD4‐apoptin protein for 6 days via the tumor epidermis exhibited a significant tumor growth inhibition because of apoptin‐mediated cell death. In addition, treatment of human hepatocarcinoma xenografts during 3 weeks showed that PTD4‐apoptin protein has significant anticancer activity, whereas control treatment with PTD4‐enhanced green fluorescence protein or saline did not. Cell death and disruption of the tumor integrity were apparent in the PTD4‐apoptin transduced xenografted tumors. As important, although PTD4‐apoptin protein could be detected in the epidermal tissue covering the subcutaneous tumor tissue and in several organs, such as liver and brain, of the treated mice, no tissue disruption or signs of cell death could be detected. Our in vivo data reveal that apoptin protein delivery constitutes a novel powerful and safe anticancer therapy. © 2009 UICC
ΔNp63α‐dependent expression of Id‐3 distinctively suppresses the invasiveness of human squamous cell carcinoma
Authors: Higashikawa Koichiro , Yoneda Shingo , Tobiume Kei , Saitoh Masao , Taki Masayuki , Mitani Yoshitsugu , Shigeishi Hideo , Ono Shigehiro , Kamata Nobuyuki
Published: January 2009

p63 is a member of the p53 family and ΔNp63α is the dominant‐expressing isoform of p63 in basal layer of normal stratified epithelium and human squamous cell carcinoma (SCC) cells. We have previously reported that down‐regulation of p63 was accompanied with epithelial‐to‐mesenchymal transition (EMT) by Snail‐expressing SCC cells, in which re‐expression of ΔNp63α diminished their invasiveness (Higashikawa K, Yoneda S, Tobiume K, Taki M, Shigeishi H, Kamata N. Snail‐induced down‐regulation of ΔNp63α acquires invasive phenotype of human squamous cell carcinoma. Cancer Res 2007;67:9207–13). In this study, we found that ΔNp63α positively regulated inhibitor of differentiation‐3 (Id‐3) expression. Id is a dominant negative regulator of E2A which is a transcriptional repressor of E‐cadherin. Enforced expression of Id‐3 was incapable of invoking E‐cadherin expression in the SCC cells with EMT phenotype, whereas it significantly impaired their invasiveness with down‐regulation of matrix‐metalloproteinase‐2 (MMP‐2) expression. Reporter gene assay revealed that the Ets‐1‐induced MMP‐2 promoter activity was suppressed by the Id‐3, while the Id‐3‐dependent E‐cadherin promoter activity was remarkably reduced in the presence of Snail. Furthermore, knockdown of p63 in SCC cells significantly decreased Id‐3 expression, in which up‐regulation of MMP‐2 expression was concomitant with the acquired invasiveness. These findings propose a particular role of the off‐signaling of the ΔNp63α‐Id‐3 axis incident to Snail‐mediated EMT for the MMP‐2‐dependent invasiveness in SCC cells. © 2009 UICC
Ghrelin inhibits early osteogenic differentiation of C3H10T1/2 cells by suppressing Runx2 expression and enhancing PPARγ and C/EBPα expression
Authors: Kim Sang Wan , Choi Ok Kyung , Jung Ju Yeon , Yang Jae‐Yeon , Cho Sun Wook , Shin Chan Soo , Park Kyong Soo , Kim Seong Yeon
Published: January 2009

Ghrelin is a 28‐residue peptide identified in the stomach as an endogenous ligand of the growth hormone secretagogue receptor that is expressed in a variety of peripheral tissues, as well as in the brain. In previous studies, ghrelin has been shown to stimulate both adipogenic differentiation from preadipocytes and osteogenic differentiation from preosteoblasts or primary osteoblasts. This study was undertaken to investigate the direct effect of ghrelin on the lineage allocation of mesenchymal stem cells (MSCs). We identified ghrelin receptor mRNA in C3H10T1/2 cells, and we found the levels of this mRNA to be attenuated during osteogenic differentiation. Treatment of cells with ghrelin resulted in both proliferation and inhibition of caspase‐3 activity. In addition, ghrelin decreased serum deprivation‐induced bax protein expression and release of cytochrome c from the mitochondria, whereas it increased bcl‐2 protein expression. Moreover, ghrelin inhibited early osteogenic differentiation, as shown by alkaline phosphatase activity and staining, and inhibited osteoblast‐specific genes expression by altering Runx2, PPARγ, and C/EBPα protein expression. J. Cell. Biochem. 106: 626–632, 2009. © 2009 Wiley‐Liss, Inc.
The TRβ1 is essential in mediating T3 action on Akt pathway in human pancreatic insulinoma cells
Authors: Verga Falzacappa Cecilia , Patriarca Valentina , Bucci Barbara , Mangialardo Claudia , Michienzi Simona , Moriggi Giulia , Stigliano Antonio , Brunetti Ercole , Toscano Vincenzo , Misiti Silvia
Published: January 2009

Thyroid hormone action, widely recognized on cell proliferation and metabolism, has recently been related to the phosphoinositide 3 kinase (PI3K), an upstream regulator of the Akt kinase and the involvement of the thyroid hormone receptor β1 has been hypothesized. The serine‐threonine kinase Akt can regulate various substrates that drive cell mass proliferation and survival. Its action has also been characterized in pancreatic β‐cells. We previously demonstrated that Akt activity and its activation in the insulinoma cell line hCM could be considered a specific target of the non‐genomic action of T3. In this study we analyzed the molecular pathways involved in the regulation of cell proliferation, survival, size, and protein synthesis by T3 in a stable TRβ1 interfered insulinoma cell line, derived from the hCM, and evidenced a strong regulation of both physiological and molecular events by T3 mediated by the thyroid hormone receptor β1. We showed that the thyroid receptor β1 mediates the T3 regulation of the cdk4·cyc D1·p21CIP1·p27KIP1 complex formation and activity. In addition TRβ1 is essential for the T3 upregulation of the Akt targets β‐catenin, p70S6K, and for the phosphorylation of Bad and mTOR. We demonstrated that the β1 receptor mediates the T3 upregulation of protein synthesis and cell size, together with the cell proliferation and survival, playing a crucial role in the T3 regulation of the PI3K/Akt pathway. J. Cell. Biochem. 106: 835–848, 2009. © 2009 Wiley‐Liss, Inc.
Unusual sterolic mixture, and 24‐isopropylcholesterol, from the sponge Ciocalypta sp. reduce cholesterol uptake and basolateral secretion in Caco‐2 cells
Authors: Do Hong Quang , Van Landeghem Laurianne , Wielgosz‐Collin Gaëtane , Takoudju Martin , Huvelin Jean‐Michel , Kornprobst Jean‐Michel , Bard Jean‐Marie , Barnathan Gilles , Nazih Hassan
Published: January 2009

An unusual sterolic mixture (82.3% of 24‐isopropylated sterols) and its major component, 24‐isopropylcholesterol, isolated from a marine sponge, Ciocalypta sp. (Halichondriidae), reduce cholesterol uptake, basolateral secretion and ACAT‐2 mRNA expression and increase the expression of ABCA1 mRNA in Caco‐2 cells. The decreases of cholesterol uptake and secretion induced by 24‐isopropylcholesterol alone were more than that of both the sterolic mixture and β‐sitosterol. These data add a new sterol, 24‐isopropylcholesterol, to sterols that may reduce intestinal cholesterol absorption. J. Cell. Biochem. 106: 659–665, 2009. © 2009 Wiley‐Liss, Inc.
The autonomous notch signal pathway is activated by baicalin and baicalein but is suppressed by niclosamide in K562 cells
Authors: Wang An‐Ming , Ku Hung‐Hai , Liang Yu‐Chih , Chen Yen‐Chou , Hwu Yuh‐Ming , Yeh Tien‐Shun
Published: January 2009

The Notch signaling pathway plays important roles in a variety of cellular processes. Aberrant transduction of Notch signaling contributes to many diseases and cancers in humans. The Notch receptor intracellular domain, the activated form of Notch receptor, is extremely difficult to detect in normal cells. However, it can activate signaling at very low protein concentration to elicit its biological effects. In the present study, a cell based luciferase reporter gene assay was established in K562 cells to screen drugs which could modulate the endogenous CBF1‐dependent Notch signal pathway. Using this system, we found that the luciferase activity of CBF1‐dependent reporter gene was activated by baicalin and baicalein but suppressed by niclosamide in both dose‐ and time‐dependent manners. Treatment with these drugs modulated endogenous Notch signaling and affected mRNA expression levels of Notch1 receptor and Notch target genes in K562 cells. Additionally, erythroid differentiation of K562 cells was suppressed by baicalin and baicalein yet was promoted by niclosamide. Colony‐forming ability in soft agar was decreased after treatment with baicalin and baicalein, but was not affected in the presence of niclosamide. Thus, modulation of Notch signaling after treatment with any of these three drugs may affect tumorigenesis of K562 cells suggesting that these drugs may have therapeutic potential for those tumors associated with Notch signaling. Taken together, this system could be beneficial for screening of drugs with potential to treat Notch signal pathway‐associated diseases. J. Cell. Biochem. 106: 682–692, 2009. © 2009 Wiley‐Liss, Inc.
Correct identification of oxidized histidine residues using electron‐transfer dissociation
Authors: Srikanth Rapole , Wilson Jonathan , Vachet Richard W.
Published: January 2009

Oxidative modification to the side chain of histidine can noticeably change the collision‐induced dissociation (CID) pathways of peptides containing this oxidized residue. In cases where an oxidized peptide consists two or more isomers differing only in the site of modification, oxidation to histidine usually causes the other oxidized sites to be mis‐assigned in CID spectra. These spectral misassignments can sometimes be avoided by using multiple stages of MS/MS (MSn) or via specially optimized liquid chromatographic separation conditions. In this manuscript, we demonstrate that these misassignments can be more readily and easily avoided by using electron‐transfer dissociation (ETD) to dissociate the oxidized peptides. Furthermore, we find that the relative insensitivity of ETD to side‐chain chemistry allows the extent of oxidative modification to be determined readily for peptide isomers having more than one site of oxidation. The current results along with previous studies of oxidized peptides suggest that ETD is probably a better technique than CID for obtaining correct sequence and modification information for oxidized peptides. Copyright © 2009 John Wiley & Sons, Ltd.
A small high‐irradiance laser ionization time‐of‐flight mass spectrometer
Authors: He Jian , Huang Rongfu , Yu Quan , Lin Yiming , Hang Wei , Huang Benli
Published: January 2009

A small high‐irradiance laser ionization time‐of‐flight mass spectrometer (LI‐TOFMS) with orthogonal sample introduction was described. High irradiance of 6 × 1010 W/cm2 at 532 nm from a Nd : YAG laser was applied in the experiment to get a high ionization degree in plasma and to dissociate the interferential polyatomic ions. Meanwhile, the interferential multiply charged ions resulted by high‐irradiance were nearly eliminated in the spectrum by utilizing helium as the buffer gas in the ion source due to three‐body recombination, which resulted in a relatively clean background. Improved signal stability was obtained by automated step moving of the sample stage in short time intervals. By using two sets of Einzel lens in transport system, nearly uniform relative sensitivity coefficients (RSCs) were achieved for most of metal elements including light ions which were detected in extremely low sensitivity in previous hexapole transportation instrument. The resolving power reaches 2200, and the detection limits (DLs) are 10−6 g/g for metal elements in the steel standard. Copyright © 2009 John Wiley & Sons, Ltd.
Determination and quantification of astragalosides in Radix Astragali and its medicinal products using LC–MS
Authors: Zu Yuangang , Yan Mingming , Fu Yujie , Liu Wei , Zhang Lin , Gu Chengbo , Efferth Thomas
Published: January 2009

In the present study, a liquid chromatography–tandem mass spectrometry method was developed for the separation and simultaneous quantification of astragalosides I–IV in samples of Radix Astragali and a medicinal product thereof (Jinqi Jiangtang tablets). Chromatographic separation was achieved on an Agilent Eclipse XDB (ODS)‐C18 column with a mobile phase consisting of acetonitrile and 0.05% formic acid aqueous solution by use of an efficient 17‐min program. A triple quadrupole mass spectrometer was operated in positive ionization mode with multiple reaction monitoring for the detection of four astragalosides. The saponin ginsenoside Rg1 (similar structure to astralagosides) was used as an internal standard. All calibration curves showed excellent linear regressions (r2 ⪈ 0.9912) within the range of tested concentrations. The intra‐ and inter‐day variations were below 4.57% in terms of RSD. The recoveries were 94.38–103.53% with RSD of 1.39–3.58% for spiked Radix Astragali samples. The method was successfully used for the analysis of samples of Radix Astragali and Jinqi Jiangtang tablets. In conclusion, we have developed a rapid, efficient, and accurate LC–MS/MS method for the detection of astragalosides, which can be applied for quality control of Radix Astragali and related medicinal products.
Prediction of supercritical fluid chromatographic retention factors at different percents of organic modifiers in mobile phase
Authors: Fatemi Mohammad H. , Malekzadeh Hanieh , Shamseddin Hoda
Published: January 2009

In this work quantitative structure‐retention relationship models were developed to predict the solute retention factors in supercritical fluid chromatography (SFC) in various organic modifiers. Data set contains the retention data of 35 various organic compounds in 0, 2, 4 and 6% of methanol in mobile phase. The obtained 140 data points were divided into training, internal and external test sets which have 93, 23 and 24 retention data. The diversity validation test was performed on data the set to ensure that the structure of the training and/or test sets can represent those of the whole ones. Descriptors which were selected by stepwise multiple linear regression (MLR) methods are: the percent of organic modifier in mobile phase, salvation connectivity index chi‐2, salvation connectivity index chi‐5, H attached to heteroatom, the 2nd structural information content and polarity parameter. These descriptors were used as features in generation of linear and non‐linear models using MLR and artificial neural network (ANN) methods, respectively. The root mean square error of MLR model are 0.116, 0.138 and 0.260 for training, internal and external test sets, respectively, while these values are 0.036, 0.097 and 0.244 for ANN model, respectively. Comparison between these values and other statistical parameters obtained from these two models reveals the credibility of ANN in prediction of solute retention factors in SFC.
HPLC of fluoroquinolone antibacterials using chiral stationary phase based on enantiomeric (3,3′‐diphenyl‐1,1′‐binaphthyl)‐20‐crown‐6
Authors: Choi Hee Jung , Cho Hwan Sun , Han Sang Cheol , Hyun Myung Ho
Published: January 2009

A residual silanol group‐protecting chiral stationary phase (CSP) based on optically active (3,3′‐diphenyl‐1,1′‐binaphthyl)‐20‐crown‐6 was successfully applied to the resolution of fluoroquinolone compounds including gemifloxacin mesylate. The chiral recognition ability of the residual silanol group‐protecting CSP was generally greater than that of the residual silanol group‐containing CSP. From these results, it was concluded that the simple protection of the residual silanol groups of the latter CSP with lipophilic n‐octyl groups can improve its chiral recognition ability for the resolution of racemic fluoroquinolone compounds. The chromatographic resolution behaviors were investigated as a function of the content and type of organic and acidic modifiers and the ammonium acetate concentration in aqueous mobile phase and the column temperature. Especially, the addition of ammonium acetate to the mobile phase was found to be a quite effective means of reducing the enantiomer retentions without sacrificing the chiral recognition efficiency of the CSP.
Acute vocal fold hemorrhage caught on video during office exam
Authors: Carroll Thomas L. , Smith Libby J.
Published: January 2009

This article presents a unique video of a laryngeal exam during which a vocal fold hemorrhage occurs. This patient had likely been suffering from intermittent vocal fold hemorrhages for the last decade due to a persistent vascular lesion and an underlying chronic cough. Laryngoscope, 2009
Novel compact laptop‐based image‐guidance system: Preliminary study
Authors: Nogueira Joao F. , Stamm Aldo C. , Lyra Macos
Published: January 2009

Objectives:

To describe a novel portable laptop‐based image‐guidance system and its preliminary navigational results.

Methods:

An optic‐based, specially developed navigational system and a life‐size endoscopic sinus anatomic model were used. The model was submitted to computer tomography (CT), and predefined anatomic landmarks were used to test the image‐guidance accuracy according to the real model.

Results:

All anatomic landmarks were identified by the image‐guidance system and all matched with endoscopic or eye views.

Conclusions:

This novel compact navigation device was shown to be fast and reliable. A larger series, involving more models, cadavers, and patients, with the evaluation of multiple anatomic points needs to be done before we can reliably determine the overall accuracy of this novel device. However, this new system is promising, and in the future it can be part of the armamentarium of otolaryngologists' personal equipment in order to perform low‐cost image‐guided surgeries in different places with the same equipment. Laryngoscope, 2009
Neuromonitoring of the external branch of the superior laryngeal nerve during minimally invasive thyroid surgery under local anesthesia: A prospective study of 10 patients
Authors: Inabnet William B. , Murry Thomas , Dhiman Shamly , Aviv Jonathan , Lifante Jean‐Christophe
Published: January 2009

Objectives/Hypothesis:

Avoiding alterations of the voice is a challenge in thyroid surgery. Identification and preservation of the external branch of the superior laryngeal nerve (EBSLN) is paramount for normal vocal function preservation after thyroidectomy. Conventional nerve monitoring requires a general anesthesia and placement of a special endotracheal tube equipped with electrodes to evoke the laryngeal nerves. This study aims to assess feasibility and efficacy of a novel technique of neuromonitoring of the EBSLN under local anesthesia during minimally invasive thyroidectomy.

Study Design; Prospective Study:

This study is a prospective trial to evaluate the efficacy of nerve monitoring of the EBSLN during minimally invasive thyroidectomy under local anesthesia. Patient self‐assessment of changes in perceived voice severity prior to and 3 weeks after surgery was assessed with the Voice Handicap Index‐10 (VHI‐10).

Results:

Thyroidectomy was successfully completed under local anesthesia in all cases. The recurrent laryngeal nerve(s) was identified and preserved in each patient as demonstrated by normal perioperative transnasal flexible laryngoscopy. A total of 15 EBSLNs were at risk, but only 8 EBSLNs (53%) were definitively identified. Neuromonitoring demonstrated preservation of the EBSLN in 100% of cases. The analysis of the results of the VHI‐10 questionnaire before and 3 weeks after surgery indicated no significant change in patients' perception of voice severity.

Conclusion:

Monitoring of the EBSLN during thyroidectomy under local anesthesia is a feasible alternative to conventional nerve monitoring under general anesthesia. This technique may be useful for the preservation of voice quality during a minimally invasive thyroidectomy under local anesthesia. Laryngoscope, 2009
Roles of vascular endothelial growth factor, Angiopoietin 1, and Angiopoietin 2 in nasal polyp
Authors: Park Seong Kook , Kim Hyeong In , Yang Young Il
Published: January 2009

Objectives/Hypothesis:

To determine the roles of vascular endothelial growth factor (VEGF), Angiopoietin (Ang)‐1, and Ang‐2 in nasal polyps (NPs) by assaying expression patterns and evaluating the effects of dexamethasone (DEX) on these factors in organ cultured NPs.

Study Design:

Prospective.

Methods:

Expression patterns of VEGF, Ang‐1, and Ang‐2 in NPs were compared with those in inferior turbinate mucosa samples. Tissue samples were analyzed using the enzyme‐linked immunosorbent assay (ELISA) and immunofluorescent staining methods. To determine the effects of DEX, NP tissues were cultured using an air‐liquid interface method. Cultures were maintained in the absence or presence of DEX (10 μM or 100 μM) for 24 hours, and tissue samples analyzed with ELISA.

Results:

VEGF and Ang‐1 levels were significantly higher, whereas the Ang‐2 level was significantly lower in NPs, compared to inferior turbinate mucosa (P < .05). In NPs, VEGF and Ang‐1 were detected in glandular epithelial, vascular endothelial, as well as stromal inflammatory cells, whereas Ang‐2 was detected only in stromal inflammatory cells. VEGF and Ang‐1 levels were significantly lower, while Ang‐2 levels were significantly higher in 100 μM DEX‐treated group than nontreated group (P < .01).

Conclusions:

Imbalance among VEGF, Ang 1, and Ang 2 may be important in the angiogenesis of NPs. Moreover, DEX can control the expression of these factors in NPs. We suggest that VEGF and Ang‐1 act as positive regulatory factors, and Ang‐2 functions as a negative regulatory factor of angiogenesis in NPs. Laryngoscope, 2009
Sonography‐assisted cutting needle biopsy in the head and neck for the diagnosis of lymphoma: Can it replace lymph node extirpation?
Authors: Pfeiffer Jens , Kayser Gian , Ridder Gerd J.
Published: January 2009

Objectives:

Malignant lymphoma frequently present with cervical lymph node enlargement. Before adequate therapy can be instituted, appropriate biopsy specimens must enable definite subclassification of the disease. While lymph node extirpation, traditionally considered the gold standard in the diagnostic evaluation of lymphoma, is invasive, diagnoses from fine needle aspiration cytology are often clinically insufficient on which to base treatment decisions. The aim of this study was to evaluate the diagnostic accuracy of cutting needle biopsy (CNB) in the management of patients in whom lymphoma was diagnosed or suspected in the head and neck.

Study Design:

Prospective quality assessment study in an academic tertiary care medical center.

Methods:

A systematic clinicopathological follow‐up study was performed over a period of 54 months, including the results of 347 CNBs in 160 patients with cervico‐facial masses. Ninety‐seven CNBs were done in 45 patients with malignant lymphoma as the final or the tentative diagnosis.

Results:

We experienced 100% success in obtaining high‐quality tissue cores. The target lymph node was correctly sampled in 41 of the 45 patients. Within these 41 patients, no false positive or false negative results were recorded. Full subclassification of the disease with prompt institution of therapy was possible in 92.3% of the lymphoma patients.

Conclusions:

CNB proved to be a sufficient alternative to open biopsy with excellent diagnostic yield and clinical usefulness. We recommend this procedure as the initial diagnostic step in patients with suspected lymphoma, either at presentation or at recurrence, and advocate its use in peripheral lymphadenopathy of the neck. Laryngoscope, 2009
The Effect of Clay Loading on the Morphology and Properties of Poly(styrene‐co‐butyl acrylate)/Clay Nanocomposites
Authors: Greesh Nagi , Hartmann Patrice C. , Sanderson Ronald D.
Published: January 2009

This paper investigates the effect of both the clay loading and the monomer feed rate on the morphology and properties of poly(styrene‐co‐butyl acrylate)‐clay nanocomposites prepared in emulsion polymerization. Analysis by X‐ray diffraction (XRD) and transmission electron microscopy (TEM) of the nanocomposites prepared by batch polymerization showed that the polymer clay nanocomposites (PCNs) with 1–3 wt.‐% clay loading resulted in intercalated structures, while exfoliated structures were obtained at 10 wt.‐% clay loading. The polymerization was also carried out with semi‐batch polymerization. The morphology, thermal stability, and mechanical properties of nanocomposites obtained were found to be more strongly dependent on the clay/polymer ratio than the monomer feed rate.

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Copolymer Sequence Distributions in Controlled Radical Polymerization
Authors: Zargar Amin , Schork F. Joseph
Published: January 2009

Although simulations of polymerizations have been performed using population‐balance and method‐of‐moments techniques to determine the properties of copolymers, the method used most often to estimate copolymer composition distribution is based on probabilistic arguments and is not entirely compatible with the population balance approach. In this paper, a model based on the method of moments is presented that determines not only the molecular weight and copolymer composition characteristics, but also allows prediction of the copolymer distribution. The method is applied to controlled‐radical polymerization. Batch polymerizations are simulated to illustrate the effect of composition drift, and shot polymerizations are simulated to show the potential to produce copolymers with customized sequence distributions.

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A new efficient explicit formulation for linear tetrahedral elements non‐sensitive to volumetric locking for infinitesimal elasticity and inelasticity
Authors: De Micheli P. O. , Mocellin K.
Published: January 2009

We introduce an innovative formulation for simple linear tetrahedral elements non‐sensitive to volumetric locking. Tetrahedral meshes enable to deal with high deformation by using efficient and robust adaptive meshers—while standard explicit formulations based on linear hexahedral elements with reduced integration and hourglassing stabilization cannot be coupled with efficient remeshing procedures. The principle of this anti‐locking modification is to impose the volumetric constraints at each node instead of at each integration point, as been done in the averaged nodal pressure formulation proposed by Bonet in 1998. However, the modification made here is material independent: the strain tensor is directly modified before any stress or pressure calculus. The formulation is extended to incompressible elasticity and von Mises incompressible isotropic inelasticity (elastic–visco‐plasticity). An infinitesimal strain formulation has been chosen in order to obtain a very simple and thus computational time saving algorithm. This choice can be easily justified taking into account the value of the critical time step in explicit simulations, especially for metal‐forming processes. Standard elastic and inelastic benchmarks issued from the literature validate qualitatively and quantitatively this promising formulation for quasi‐incompressible deformations cases. Copyright © 2009 John Wiley & Sons, Ltd.
ARGET ATRP of methyl methacrylate in the presence of nitrogen‐based ligands as reducing agents
Authors: Kwak Yungwan , Matyjaszewski Krzysztof
Published: January 2009

BACKGROUND: Activators regenerated by electron transfer for atom transfer radical polymerization (ARGET ATRP) employs reducing agents (e.g. ascorbic acid, tin(II) 2‐ethylhexanoate) to continuously reduce a deactivator Cu(II) to an activator Cu(I) species. In this work, copper‐mediated ARGET ATRP of methyl methacrylate (MMA) was studied in the presence of excess aliphatic nitrogen‐based ligands that served not only as ligands but also as reducing agents.

RESULTS: Reduction of Cu(II) to Cu(I) by an excess amount of nitrogen‐based ligand was followed by UV‐visible spectroscopy. Well‐controlled poly(methyl methacrylate) (PMMA) with low polydispersity index (PDI) was prepared in the presence of Cu(II)Br2/excess ligand via ARGET ATRP. Chain extension of PMMA with MMA was successful, resulting in low‐PDI PMMA and demonstrating well‐maintained end‐group functionality.

CONCLUSION: Well‐controlled PMMA with low PDI was prepared via ARGET ATRP in the presence of Cu(II) and nitrogen‐based ligands without any additional reducing agent. Aliphatic nitrogen‐based ligands for ATRP can serve as reducing agents as well as ligands. Copyright © 2009 Society of Chemical Industry
Unraveling theS‐nitrosoproteome: Tools and strategies
Authors: López‐Sánchez Laura M. , Muntané Jordi , de la Mata Manuel , Rodríguez‐Ariza Antonio
Published: January 2009

One of the major tasks to be accomplished in the postgenomic era is the characterization of PTMs in proteins. TheS‐nitrosation of protein thiols is a redox‐based PTM that modulating enzymatic activity, subcellular localization, complex formation, and degradation of proteins, largely contributes to the complexity of cellular proteomes. Although the detection ofS‐nitrosated proteins is problematical due to the lability ofS‐nitrosothiols, with the improvement of molecular tools an increasing range of proteins has been shown to undergoS‐nitrosation. We here review recent proteomic approaches for the systematic assessment of potential targets for proteinS‐nitrosation. The development of new analytical methods and strategies over the past several years now allows us to investigate the nitrosoproteome on a global scale.
A role for lipid droplets in inter‐membrane lipid traffic
Authors: Zehmer John K. , Huang Youguo , Peng Gong , Pu Jing , Anderson Richard G. W. , Liu Pingsheng
Published: January 2009

All cells have the capacity to accumulate neutral lipids and package them into lipid droplets. Recent proteomic analyses indicate that lipid droplets are not simple lipid storage depots, but rather complex organelles that have multiple cellular functions. One of these proposed functions is to distribute neutral lipids as well as phospholipids to various membrane‐bound organelles within the cell. Here, we summarize the lipid droplet‐associated membrane‐trafficking proteins and review the evidence that lipid droplets interact with endoplasmic reticulum, endosomes, peroxisomes, and mitochondria. Based on this evidence, we present a model for how lipid droplets can distribute lipids to specific membrane compartments.
Time‐dependent morphology development in segmented polyetherurea copolymers based on aromatic diisocyanates
Authors: Yilgor I. , Yilgor E. , Das S. , Wilkes G. L.
Published: January 2009

Time‐dependent morphology development in segmented polyureas obtained by the stoichiometric reactions between amine terminated poly(tetramethylene oxide) (PTMO) and aromatic diisocyanates were investigated. Polyureas were prepared by reacting aminopropyl terminated PTMO oligomer (Mn = 1100 g/mol) and various aromatic diisocyanates, such as 1,4‐phenylene diisocyanate (PPDI), 1,3‐phenylene diisocyanate (MPDI), diphenylmethane diisocyanate (MDI), and tolylene diisocyanate (TDI). Time‐dependent FTIR studies were conducted on thin films cast onto KBr discs, which were annealed at 200 °C for 10 min in an air oven. After removing from the oven, samples were placed into the FTIR spectrometer at room temperature, where time‐dependent spectra were recorded until equilibrium was reached. Time‐dependent peak reorganization in 3500–3100 cm−1 (NH region), 1750–1450 cm−1 (CO region or amide I and amide II regions), and 1180–1020 cm−1 (COC) were monitored. Depending on the chemical structure and the symmetry of the diisocyanate, major differences were observed in the time needed to reach an equilibrium morphology in these homologous poly(ether urea) copolymers. Symmetric PPDI‐based polyurea reached equilibrium in about 1 h compared with its asymmetric MPDI‐based counterpart, which needed about 150 h. Microphase development of the MPDI urea was also characterized by AFM, which gave similar results. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 471–483, 2009
Simulation study of aggregate morphologies formed by ABC linear triblock copolymers in a selective solvent through the self‐consistent field theory
Authors: Ma Zengwei , Jiang Wei
Published: January 2009

The effect of the hydrophobic properties of blocks B and C on the aggregate morphologies formed by ABC linear triblock copolymers in selective solvent was studied through the self‐consistent field theory. Five typical micelles, such as core‐shell‐corona, hamburger‐like, segmented‐wormlike, were obtained by changing the hydrophobic properties of blocks B and C. The simulation results indicate that the shape and size of micelle are basically controlled by the hydrophobic degree of the middle block B, whereas the type of micelle is mainly determined by the hydrophobic degree of the end block C. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 484–492, 2009
Fabrication of carbon fibers with nanoporous morphologies from electrospun polyacrylonitrile/poly(L‐lactide) blends
Authors: Ji Liwen , Medford Andrew J. , Zhang Xiangwu
Published: January 2009

Porous carbon nanofibers were prepared through electrospinning a blend solution of polyacrylonitrile and poly(L‐lactide), followed by carbonization at different temperatures and in different atmospheres. Structural features of these porous carbon nanofibers were characterized using scanning electron microscopy, transmission electron microscopy, thermogravimetric analysis, X‐ray powder diffraction, and Raman spectroscopy. Surface area and pore structure were evaluated using the nitrogen adsorption technique. It was found that carbon fibers prepared by this scalable and relatively economical method exhibited a porous surface morphology with high specific surface area and large pore volume. The fiber diameter, surface area, pore volume, bulky crystalline structure, and surface crystalline structure of these carbon nanofibers showed a strong dependence on the polymer precursor composition and carbonization condition. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 493–503, 2009
X‐ray diffraction study of the thermal expansion behavior of cellulose triacetate I
Authors: Wada Masahisa , Hori Ritsuko
Published: January 2009

Highly crystalline samples of cellulose triacetate I (CTA I) were prepared from highly crystalline algal cellulose by heterogeneous acetylation. X‐ray diffraction of the prepared samples was carried out in a helium atmosphere at temperatures ranging from 20 to 250 °C. Changes in seven d‐spacings were observed with increasing temperature due to thermal expansion of the CTA I crystals. Unit cell parameters at specific temperatures were determined from these d‐spacings by the least squares method, and then thermal expansion coefficients (TECs) were calculated. The linear TECs of the a, b, and c axes were αa = 19.3 × 10−5 °C−1, αb = 0.3 × 10−5 °C−1 (T < 130 °C), αb = −2.5 × 10−5 °C−1 (T > 130 °C), and αc = −1.9 × 10−5 °C−1, respectively. The volume TEC was β = 15.6 × 10−5 °C−1, which is about 1.4 and 2.2 times greater than that of cellulose Iβ and cellulose IIII, respectively. This large thermal expansion could occur because no hydrogen bonding exists in CTA I. © 2009 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 47: 517–523, 2009
Amorphous and microcrystalline GeC:H films prepared by magnetron sputtering
Authors: Saito N. , Iwata H. , Nakaaki I. , Nishioka K.
Published: January 2009

Hydrogenated germanium‐carbon alloy (GeC:H) films have been deposited by a reactive rf magnetron sputtering of Ge in methane–argon gas mixtures. As the second sputtering gas, helium is utilized in order to control the film properties. The effect of helium partial pressure ratio R to the total sputtering gas on the structural, optical and electrical properties of the films was investigated. The films show the amorphous nature in the low‐R range up to 60%. In the high‐R range above 60%, the bonding configuration in IR spectra changes, the diffraction lines of XRD appear, the optical bandgap decreases, and the dc conductivity increases clearly. It is found from these data that the microcrystallization of GeC:H films could be achieved by introducing helium during the sputtering process. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Nanoscale granular boundaries in polycrystalline Pb0.75Sn0.25Te: an innovative approach to enhance the thermoelectric figure of merit
Authors: Ji Xiaohua , Zhang Bo , Su Zhe , Holgate Tim , He Jian , Tritt Terry M.
Published: January 2009

Pb0.75Sn0.25Te is an important PbTe‐based thermoelectric material that has been extensively applied in thermoelectric power generation for intermediate‐temperature use. Alkali metal (Na, K) hydrothermal treatments were performed on micro‐sized Pb0.75Sn0.25Te particles. After treatment, numerous nanorods with diameters of ∼20 nm and lengths of up to 200 nm were found uniformly embedded onto the surface of bulk particles. These nanorods contained surfaces that were subsequently transformed into nanosized fractal granular grain boundaries upon hot pressing of the treated Pb0.75Sn0.25Te bulk particles. The presence of this nanoscaled grain boundary results in an improvement of the ratio of the electrical conductivity to the thermal conductivity, via significantly reducing the lattice thermal conductivity while without appreciably affecting the Seebeck coefficient or the electrical resistivity. As a result, a thermoelectric figure of merit Z ∼ 1.1 × 10–3 K–1 (∼0.8 × 10–3 K–1) is obtained in Na (K)‐processed samples at ∼425 K (475 K), which is notably improved from Z ∼ 0.7 × 10–3 K–1 at ∼490 K in a bulk reference sample. The present work provides a new and novel avenue by which the lattice thermal conductivity of a polycrystalline system can be ‘essentially decoupled’ from the electronic properties and thus independently ‘tuned’ via controlling the micro‐morphology of the inter‐grain boundary. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Electrochemical characterization of the effect of gold nanoparticles on the electron transfer of cytochrome c
Authors: Caban Karolina , Offenhäusser Andreas , Mayer Dirk
Published: January 2009

In this work cytochrome c (cyt c), a heme‐containing redox protein, was used as a model system for studying general aspects of wiring proteins into conceptual metal–biomolecule–metal nanoparticle junctions. Electron transfer kinetics of cyt c immobilized on Au(111) via MUA spacer has been investigated in the absence and presence of surface‐bound gold nanoparticles. The combined effect of size and immobilization time of AuNPs as well as their binding site to cyt c on the tunnelling rate of the protein has been explored. It has been observed that electrostatic binding of 5 nm‐in‐diameter gold nanoparticles obviously accelerates the electron transfer rate of cyt c. Potential applications of gold nanoparticles as electric contacts in nanodevices as well as their beneficial or adverse health effects have been suggested. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)