bluuebunny/crossref_metadata_2025 huggingface dataset:
KOC (K homology domain containing protein Overexpressed in Cancer) and S100A4‐protein immunoreactivity improves the diagnostic sensitivity of biliary brushing cytology for diagnosing pancreaticobiliary malignancies
Authors: Ligato Saverio , Zhao Huicong , Mandich Daniza , Cartun Richard W.
Published: July 2008

Biliary tract brush cytology is one of the favored methods of evaluating lesions of the pancreatobiliary tract. However, although its specificity has been reported to be high (91–100%), the sensitivity is lower (30–88%). In this study we applied KOC and S100A4 protein immunocytochemistry to assess their potential use as adjunct markers in differentiating benign from malignant cells, and improve the diagnostic sensitivity of this method for pancreatobiliary malignancies.

The authors examined KOC and S100A4 protein expression in 44 alcohol‐fixed cytology specimens obtained by biliary brushings. Diagnoses included: (1) benign/atypical favor reactive (20 cases), (2) atypical/not diagnostic of malignancy (3 cases), and (3) suspicious for malignancy/malignant (21 cases). Alcohol‐fixed Papanicolaou‐stained slides (PAP) were stained with monoclonal antibody to KOC/L523S and polyclonal antibody to S100A4 protein. Results were recorded as negative or positive.

Twenty‐four cases were confirmed positive for adenocarcinoma and 20 cases were negative. The sensitivity and specificity of cytology was 83 and 95%, KOC showed a sensitivity of 92% and specificity of 95%. S100A4 protein showed a sensitivity of 79% and a specificity of 95%. The combined use of KOC and S100A4 protein showed a sensitivity of 100% and a specificity of 95%, respectively.

The concurrent use of KOC and S100A4 protein improves the diagnostic sensitivity of biliary brushings cytology and demonstrates similar specificity as cytology alone in the diagnosis of pancreatobiliary malignancy. Diagn. Cytopathol. 2008; 36: 561–567. © 2008 Wiley‐Liss, Inc.
Fine‐needle aspiration biopsy of primary osteosarcoma of the thyroid: Report of a case and review of the literature
Authors: Tong Guo‐Xia , Hamele‐Bena Diane , Liu Jeffrey C. , Horst Basil , Remotti Fabrizio
Published: July 2008

Primary osteosarcoma of the thyroid is an extremely rare tumor, with only 27 well‐documented cases reported in the literature, including only one in the cytology literature. We describe here an additional case with fine‐needle aspiration biopsy findings. A 60‐year‐old woman presented with a 1‐month history of progressive midline neck swelling. CT and ultrasound demonstrated a large thyroid mass with tracheal compression. Fine‐needle aspiration biopsies were performed and showed pleomorphic spindle and epithelioid neoplastic cells, multinucleated giant cells, and scant metachromatic extracellular matrix material. Cell block sections contained minute tissue fragments with neoplastic spindle cells. Immunohistochemical stains showed the tumor cells to be positive for vimentin and negative for cytokeratins, TTF‐1, calcitonin, synatophysin, chromogranin, and S‐100 protein, suggesting a sarcoma; however, the differential diagnosis also included anaplastic thyroid carcinoma and medullary thyroid carcinoma. Tissue biopsy revealed a high‐grade spindle cell neoplasm with osteoid production, consistent with osteosarcoma of the thyroid. The patient developed a large pulmonary embolus and superior vena cava syndrome and no further surgical intervention was performed. She died 5 weeks after the initial diagnosis. Upon retrospective review, the cytologic features resemble osteosarcoma in other areas. Although cytologic features on fine‐needle aspiration biopsy may suggest a diagnosis of this rare entity, definitive diagnosis should be deferred to histologic examination. Diagn. Cytopathol. 2008; 36: 589–594. © 2008 Wiley‐Liss, Inc.
HBME‐1 and CK19 are highly discriminatory in the cytological diagnosis of papillary thyroid carcinoma
Authors: Nga Min‐En , Lim Gkeok Stzuan , Soh Chai Hong , Kumarasinghe Marian Priyanthi
Published: July 2008

The cytologic diagnosis of papillary thyroid carcinoma is straightforward in most instances. However, there are some mimics including goitrous nodules and Hurthle cell neoplasms. Many studies have shown the combination of HBME‐1 and CK19 expression to be useful in reaching a correct histologic diagnosis on tissue sections. We aim to assess the value of these markers in the setting of cell blocks prepared from needle aspiration specimens. We performed immunohistochemical staining of HBME‐1 and CK19 on cell block material from 22 thyroid nodules that also had follow‐up histology. Both CK19 and HBME‐1 were strongly positive in all nine cases of papillary thyroid carcinoma, the latter showing distinct luminal accentuation. In the non‐papillary carcinomas, none showed positivity for both HBME‐1 and CK19. Two of six Hurthle cell neoplasms were positive for CK19, however all were negative for HBME‐1. One of nine goitrous nodules was strongly positive for HBME‐1 with luminal/membranous staining, but this were negative for CK19.

The sensitivity, specificity and positive predictive value of HBME‐1 in distinguishing between papillary thyroid carcinoma and goitrous nodules/Hurthle cell neoplasms were found to be 100%, 92.9% and 0.9, respectively; and that of HBME‐1 and CK19 combination was 100%, 100% and 1.

We thus conclude that the combination of positive HBME‐1 (luminal/membranous) and CK 19 (cytoplasmic) staining on cell blocks of thyroid cytologic specimens is highly discriminatory in the diagnostic workup for papillary thyroid carcinoma. Diagn. Cytopathol. 2008; 36: 550–556. © 2008 Wiley‐Liss, Inc.
WCAFTI: Worrisome cytologic alterations following tissue infarction; a mimicker of malignancy in breast cytology
Authors: Kavdia Reeti , Kini Usha
Published: July 2008

The acronym WCAFTI (cafti)—(Worrisome cytologic alterations following tissue infarction) is introduced here for the first time for the entity which describes the spectrum of cytologic changes seen in spontaneous infarction of an epithelial lesion. The pathology may be responsible for abnormal cytologic findings such as cellular dyshesiveness, nuclear enlargement with cytoplasmic blurring and irregular nuclei. Although, it is a rare event, it is essential for a cytologist to be aware of this new acronym WCAFTI to avoid misinterpretation of atypical cells and necrosis as indicators of malignancy. It is typically described here in a fibroadenoma from a 49‐year‐old female who sought medical help for pain in left breast mass. Diagn. Cytopathol. 2008; 36: 586–588. © 2008 Wiley‐Liss, Inc.
Fine‐needle aspiration cytology of pulmonary mucinous cystadenocarcinoma
Authors: Chhieng David C.
Published: July 2008

A 64‐year‐old man presented with symptoms of a lung infection. Radiologic work‐up revealed opacity in the upper lobe of right lung. A computer tomographic (CT) guided fine‐needle aspiration biopsy revealed sheets and clusters of mild to moderately atypical epithelial cells, small amount of mucin, histiocytes, multinucleated giant cells, and stromal fragments. The differential diagnosis included an inflammatory process and a well‐differentiated adenocarcinoma. A lobectomy was performed and revealed abundant extracellular mucin surrounded partially by a thick fibrous wall, which was lined by neoplastic glandular cells. The histology was consistent with a pulmonary mucinous cystadenocarcinoma. Fibroblastic proliferation and foreign‐body giant reaction secondary to extravasation of mucin were also noted. The patient was disease free 1 year after initial diagnosis. The relative lack of mucin as well as the presence of well‐differentiated neoplastic cells, the inflammatory response to extravasated mcuin constitutes a potential pitfall in recognizing pulmonary mucinous cystadenocarcinoma cytologically. Diagn. Cytopathol. 2008; 36: 581–585. © 2008 Wiley‐Liss, Inc.
Fine‐needle aspiration of metastatic prostatic neuroendocrine carcinomas: Cytomorphologic and immunophenotypic features
Authors: Cai Guoping , Ramdall Risha B. , Levine Pascale , Yang Grace C. H.
Published: July 2008

Metastatic prostatic carcinoma may, in rare occasions, present as a neuroendocrine tumor. Its recognition is crucial to avert a wrongful exclusion of prostate as a primary site. We report five cases of metastatic prostatic neuroendocrine carcinoma diagnosed by image‐guided fine‐needle aspiration biopsy. The aspirate smears showed loosely cohesive or dyscohesive clusters of tumor cells with scanty (three cases) to moderate amount (two cases) of cytoplasm, speckled or coarse chromatin and inconspicuous nucleoli. Nuclear molding and necrosis were focally present in two cases. Immunohistochemically, the tumor cells were positive for synaptophysin or/and chromogranin, but negative for prostatic specific antigen and prostatic specific acid phosphatase. Review of prior prostate biopsies/resections revealed adenocarcinoma with focal neuroendocrine differentiation in all cases, with two cases being newly recognized on retrospective review. Confirming neuroendocrine differentiation in the prior biopsy/resection may help to establish a link between metastasis and prostate primary. Diagn. Cytopathol. 2008; 36: 545–549. © 2008 Wiley‐Liss, Inc.
Adoption of Virtual Try-on technology for online apparel shopping
Authors: Kim Jiyeon , Forsythe Sandra
Published: July 2008

Virtual try-on technology (referred to in this article as Virtual Try-on) can deliver product information that is similar to the information obtained from direct product examination. In addition, the interactivity and customer involvement created by Virtual Try-on can enhance the entertainment value of the online shopping experience. We used focus group interviews and an online national survey to investigate online apparel shoppers’ use of Virtual Try-on to reduce product risks and increase enjoyment in online shopping.We also examined the impact of two important external variables (innovativeness and technology anxiety) that are not included in the electronic Technology Acceptance Model (e-TAM) but were expected to influence adoption of Virtual Try-on and whether or not gender differences existed in the Virtual Try-on adoption process. We examined this dual (functional and hedonic) role of Virtual Try-on by applying a modified e-TAM model to the Virtual Try-on technology adoption process and tested model invariance among male and female shoppers using Virtual Try-on in a simulated online shopping experience. The extended research model was validated in the context of Virtual Try-on adoption.Technology anxiety and innovativeness had significant moderating effects on the relationship between attitude and use of Virtual Try-on technology; however, there was no significant gender difference in the overall adoption process for Virtual Try-on.
Effects of androgens on insulin action in women: is androgen excess a component of female metabolic syndrome?
Authors: Corbould A.
Published: July 2008

Hyperinsulinemia as a consequence of insulin resistance causes hyperandrogenemia in women. The objective was to review evidence for the converse situation, i.e. whether androgens adversely influence insulin action. Androgen excess could potentially contribute to the pathogenesis of insulin resistance in women with polycystic ovary syndrome (PCOS), metabolic syndrome/type 2 diabetes, and in obese peripubertal girls. An Entrez‐PubMed search was conducted to identify studies addressing the relationship of androgens with metabolic syndrome/type 2 diabetes in women. Studies reporting outcomes of androgen administration, interventions to reduce androgen effects in hyperandrogenemic women, and basic studies investigating androgen effects on insulin target tissues were reviewed. Multiple studies showed associations between serum testosterone and insulin resistance or metabolic syndrome/type 2 diabetes risk in women, but their cross‐sectional nature did not allow conclusions about causality. Androgen administration to healthy women was associated with development of insulin resistance. Intervention studies in women with hyperandrogenism were limited by small subject numbers and use of indirect methods for assessing insulin sensitivity. However, in three of the seven studies using euglycemic hyperinsulinemic clamps, reduction of androgen levels or blockade of androgen action improved insulin sensitivity. Testosterone administration to female rats caused skeletal muscle insulin resistance. Testosterone induced insulin resistance in adipocytes of women in vitro. In conclusion, the metabolic consequences of androgen excess in women have been under‐researched. Studies of long‐term interventions that lower androgen levels or block androgen effects in young women with hyperandrogenism are needed to determine whether these might protect against metabolic syndrome/type 2 diabetes in later life. Copyright © 2008 John Wiley & Sons, Ltd.
Genetic variants in protein kinase C zeta gene and type 2 diabetes risk: a case‐control study of a Chinese Han population
Authors: Qin Lei , Zhou Ling , Wu Xueji , Cheng Jinluo , Wang Jingsong , Du Yunfeng , Hu Jihong , Shen Moyu , Zhou Jinyi
Published: July 2008

Background

Previous investigations of the protein kinase C zeta (PRKCZ) gene, a susceptibility factor for type 2 diabetes mellitus (T2DM), have focussed on its single nucleotide polymorphisms (SNPs). In a departure from these earlier studies, we tested six tagging markers of PRKCZ based on the Hapmap database to evaluate their association with T2DM.

Methods

PCR‐RFLP was performed to test the genotypes in type 2 diabetes patients (n = 343) and normal controls (n = 429). Insulin‐related indexes were calculated from levels of fasting plasma insulin (FPI) and fasting plasma glucose (FPG).

Results

The variant genotypes, rs3753242TT, rs2503706CT, rs2503706CT/ TT and rs262654TT were associated with T2DM. And the significance remained for rs3753242 TT (p < 0.001) after the false discovery rate (FDR) correction. There was a doubling in the prevalence of the TTGCCC haplotype in the case subjects (14.2%) compared with the control subjects (6.9%) [OR (95% CI) = 2.19(1.49–3.22)]. In the control group, none of the haplotypes studied was associated with insulin‐related indexes.

Conclusions

The PRKCZ gene variants associated with the development of T2DM in this study must be investigated in a larger population to reveal any potential effects on metabolism. Copyright © 2008 John Wiley & Sons, Ltd.
Globular adiponectin stimulates glucose transport in type 2 diabetic muscle
Authors: Kuoppamaa Heidi , Skrobuk Paulina , Sihvo Maarit , Hiukka Anne , Chibalin Alexander V. , Zierath Juleen R. , Koistinen Heikki A.
Published: July 2008

Background

Adiponectin acts as an insulin sensitizer in rodent models. The direct effect of adiponectin in intact type 2 diabetic muscle is unknown. We examined whether adiponectin stimulates glucose transport in isolated skeletal muscle strips from type 2 diabetic men.

Methods

We obtained open muscle biopsies from 12 men with type 2 diabetes (56 ± 1 years, 30.5 ± 1.1 kg/m2), and from 15 non‐diabetic men (59 ± 1 years, 28.0 ± 1.0 kg/m2). Skeletal muscle strips were isolated and exposed to globular adiponectin (2.5 µg/mL), insulin (120 nM) and/or AICAR (1 mM) in vitro for 1 h. Glucose transport was analysed by accumulation of intracellular 3‐O‐methyl [3H] glucose, phosphorylation of Akt‐Ser473 and Akt‐Thr308 was determined using phosphospecific antibodies, and adiponectin receptor 1 and 2 content was measured using specific antibodies.

Results

Globular adiponectin increased glucose transport rate by 1.3‐fold (P < 0.01) in type 2 diabetic, but not in non‐diabetic muscle. Insulin‐stimulated glucose transport rate was unaltered by exposure to globular adiponectin in either group. AICAR increased glucose transport and enhanced insulin‐stimulated glucose transport in type 2 diabetic and non‐diabetic muscles. Insulin‐stimulated phosphorylation of Akt‐Ser473 or Akt‐Thr308 was comparable in type 2 diabetic and non‐diabetic muscles, and unaltered by the addition of globular adiponectin in either group. Adiponectin receptor expression was similar in skeletal muscle from type 2 diabetic and non‐diabetic men.

Conclusions

Globular adiponectin directly increases glucose transport in skeletal muscle from type 2 diabetic patients. This may occur via Akt‐independent signalling routes. Copyright © 2008 John Wiley & Sons, Ltd.
Two Hexanickel‐Substituted Keggin‐Type Germanotungstates
Authors: Zhao Jun‐Wei , Zhang Jie , Song You , Zheng Shou‐Tian , Yang Guo‐Yu
Published: July 2008

Two new inorganic–organic hybrid germanotungstates built from trivacant Keggin fragments and in situ generated hexanickel clusters [Ni(en)2]0.5[{Ni6(μ3‐OH)3(en)3(H2O)6}(B‐α‐GeW9O34)]·3H2O (1) and [{Ni6(μ3‐OH)3(dap)3(H2O)6}(B‐α‐GeW9O34)]·H3O·4H2O (2) (en = ethylenediamine and dap = 1,2‐diaminopropane) were hydrothermally synthesized and characterized by IR spectroscopy, elemental analysis, thermogravimetric analysis, single‐crystal X‐ray diffraction and magnetic analysis. Compound 1 crystallizes in the monoclinic space group P21/n; whereas compound 2 crystallizes in the monoclinic space group P21/c. Single‐crystal X‐ray diffraction indicates that both contain a hexa‐NiII‐substituted trivacant Keggin unit [{Ni6(μ3‐OH)3(L)3(H2O)6}(B‐α‐GeW9O34)]– (L = en or dap). Magnetic susceptibility measurements show the presence of ferromagnetic coupling interactions within the hexa‐NiII clusters for 1 and 2. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Metal‐Ion‐Mediated Base Pairs in Nucleic Acids
Authors: Müller Jens
Published: July 2008

Nucleic acids and their analogues raise more and more interest in research areas outside biology and biochemistry. The functionalization of these evolutionary optimized self‐assembling macromolecules with metal ions widens their applicability even further. Previous efforts to incorporate metal ions site‐specifically into nucleic acids focused on the covalent attachment of appropriate ligands to either the sugar phosphate backbone or the nucleobases. More recently, the use of metal‐ion‐mediated base pairs, i.e. the replacement of natural nucleobases by ligands, was suggested as an alternative means. This microreview discusses selected examples of metal‐ion‐mediated base pairs, including those that comprise unmodified natural nucleobases, and describes possible applications for the resulting metal‐modified nucleic acids. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Lanthanide Complexes and Quantum Dots: A Bright Wedding for Resonance Energy Transfer (Eur. J. Inorg. Chem. 21/2008)
Authors: Charbonnière Loïc J. , Hildebrandt Niko
Published: July 2008

The cover picture shows the schematic realization of a homogeneous fluoroimmunoassay using Förster resonance energy transfer (FRET) from luminescent lanthanide complexes (LLCs – an example of a Tb complex is shown in the top right corner) to a biocompatible CdSe/ZnS quantum dot (QD). Excitation of the immunocomplex formed by the association of QD‐labeled antibodies, antigen and LLC‐labeled antibodies by UV light (e.g. 315 nm) leads to a long‐lived Tb and QD luminescence (luminescence spectra shown in the bottom right corner) due to FRET sensitization by the LLCs. This new immunoassay approach opens doors to extremely sensitive background‐free fluoroimmunoassays suitable for multiplexing by using several different QDs as FRET acceptors with a single LLC donor. Details are discussed in the Microreview by L. J. Charbonnière and N. Hildebrandt on p. 3241 ff.
Regioselective Three‐Component Synthesis of Highly Fluorescent 1,3,5‐Trisubstituted Pyrazoles
Authors: Willy Benjamin , Müller Thomas J. J.
Published: July 2008

3,5‐Disubstituted and 1,3,5‐trisubstituted pyrazoles are readily synthesized from acyl chlorides, terminal alkynes, and hydrazines by a consecutive one‐pot three‐component Sonogashira coupling/Michael addition/cyclocondensation sequence in good to excellent yields. These pyrazoles are highly fluorescent, both in solution and in the solid state. Investigation of the electronic properties by UV/Vis and fluorescence spectroscopy and by DFT and ZINDO CI computations reveal that the excited state is highly polar and allows fine‐tuning of the absorption and emission properties. X‐ray structure analyses of 3,5‐disubstituted pyrazoles reveal self‐organization by hydrogen bonding and π‐stacking. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)
Field‐Effect Nanoparticle‐Based Glucose Sensor on a Chip: Amplification Effect of Coimmobilized Redox Species
Authors: Gun Jenny , Schöning Michael J. , Abouzar Maryam H. , Poghossian Arshak , Katz Evgeny
Published: July 2008

A capacitive EIS (electrolyte‐insulator‐semiconductor) structure was modified with gold nanoparticles together with glucose oxidase and used as field‐effect‐based glucose biosensor using the constant capacitance mode. Co‐immobilization of ferrocene redox species resulted in a two‐fold increase of the biosensor sensitivity. The effect was explained by the hydrogen peroxide‐mediated oxidation of ferrocene resulting in a pool of charged species at the interface increasing the sensor response towards glucose. The studied approach was suggested as a general means to amplify signals from Si chip‐based field‐effect enzyme biosensors.
Direct Electrochemistry and Electrocatalysis of Myoglobin Immobilized on Gold Nanoparticles/Carbon Nanotubes Nanohybrid Film
Authors: Cao Wei , Wei Cuimei , Hu Jingbo , Li Qilong
Published: July 2008

A novel nanohybrid material, constructed by gold nanoparticles (GNPs) and multiwalled carbon nanotubes (MWNTs), was designed for immobilization and biosensing of myoglobin (Mb). Morphology of the nanohybrid film was characterized by SEM. UV‐vis spectroscopy demonstrated that Mb on the composite film could retain its native structure. Direct electrochemistry of Mb immobilized on the GNPs/MWNTs film was investigated. The immobilized Mb showed a couple of quasireversible and well‐defined cyclic voltammetry peaks with a formal potential of about −0.35 V (vs. Ag/AgCl) in pH 6.0 phosphate buffer solution (PBS) solution. Furthermore, the modified electrode also displayed good sensitivity, wide linear range and long‐term stability to the detection of hydrogen peroxide. The experiment results demonstrated that the hybrid matrix provided a biocompatible microenvironment for protein and supplied a necessary pathway for its direct electron transfer.
Calculation of the isoelectric point of tryptic peptides in the pH 3.5–4.5 range based on adjacent amino acid effects
Authors: Cargile Benjamin J. , Sevinsky Joel R. , Essader Amal S. , Eu Jerry P. , Stephenson James L.
Published: July 2008

Current algorithms for the calculation of peptide or protein pI, based on the charge associated with individual amino acids, can calculate pI values to within ±0.2 pI units. Here, we present a new pI calculation algorithm that takes into account the effect of adjacent amino acids on the pI value. The algorithm accounts for the effect of adjacent amino acids ± 3 residues away from a charged aspartic or glutamic acid, as well as effects on the free C terminus, and applies a correction term to the corresponding pK values. The correction increments are derived from a 5000‐peptide training set using a genetic optimization approach. The accuracy of the new pI values obtained with this method approaches the error associated with the manufacture of the IPG strip (<±0.03 pI units). The approach is demonstrated for cytosolic cell extracts derived from the breast‐cancer cell line DU4475, and from membrane preparations from human lung‐tissue samples. One potential application of a more highly accurate pI calculation is data filtering of MS/MS outputs that will allow for more complex database searches including gene finding, and validation, and detection of coding single‐nucleotide polymorphisms in their expressed form.
Surface modification of polymer microfluidic devices using in‐channel atom transfer radical polymerization
Authors: Sun Xuefei , Liu Jikun , Lee Milton L.
Published: July 2008

In‐channel atom transfer radical polymerization (ATRP) was used to graft a PEG layer on the surface of microchannels formed in poly(glycidyl methacrylate)‐co‐(methyl methacrylate) (PGMAMMA) microfluidic devices. The patterned and cover plates were first anchored with ATRP initiator and then thermally bonded together, followed by pumping a solution containing monomer, catalyst, and ligand into the channel to perform ATRP. A PEG‐functionalized layer was grafted on the microchannel wall, which resists protein adsorption. X‐ray photoelectron spectroscopy (XPS) was used to investigate the initiator‐bound surface, and EOF was measured to evaluate the PEG‐grafted PGMAMMA microchannel. Fast, efficient, and reproducible separations of amino acids, peptides, and proteins were obtained using the resultant microdevices. Separation efficiencies were higher than 1.0×104 plates for a 3.5 cm separation microchannel. Compared with microdevices modified using a previously reported ATRP technique, these in‐channel modified microdevices demonstrated better long‐term stability.
Use of quasi‐isoelectric buffers to limit protein adsorption in capillary zone electrophoresis
Authors: Poitevin Martine , Hammad Karim , Ayed Ichraf , Righetti Pier Giorgio , Peltre Gabriel , Descroix Stephanie
Published: July 2008

The use of quasi‐isoelectric buffers consisting of narrow pH cuts of carrier ampholytes (NC) has been investigated to limit protein adsorption on capillary walls during capillary zone electrophoresis experiments. To quantify protein adsorption on the silica surface, a method derived from that of Towns and Regnier has been developed. α‐Lactalbumin (14 kDa, pI 4.8) and α–chymotrypsinogen A (25 kDa, pI 9.2) have been used as model proteins. Acidic narrow pH cuts of carrier ampholytes (NC, pH 3.0) obtained from fractionation of Serva 4‐9 carrier ampholytes were used as BGE in bare‐silica capillaries, and allowed to decrease significantly protein adsorption, as compared to experiments performed with classical formate buffer. The use of NC as BGE appeared to be as efficient as the use of polydimethylacrylamide coating to prevent protein adsorption. This increase of protein recovery when using NC was attributed to the interaction of carrier ampholytes with the silica surface, leading to a shielding of the capillary wall.
Preparation of a PET‐Hydrolyzing Lipase fromAspergillus oryzaeby the Addition of Bis(2‐hydroxyethyl) Terephthalate to the Culture Medium and Enzymatic Modification of PET Fabrics
Authors: Wang X. , Lu D. , Jönsson L. J. , Hong F.
Published: July 2008

Optimization of cultivation conditions for lipase production and the preparation of a specific lipase catalyzing the hydrolysis of polyethylene terephthalate (PET) by Aspergillus oryzae CCUG 33812 as well as modification of PET fabrics by the enzyme were investigated. The lipase activity produced by the fungus after the addition of olive oil was not efficient in changing the properties of PET samples. In order to obtain lipase activity directed toward the hydrolysis of PET, two derivatives of terephthalic acid (TPA), namely diethyl p‐phthalate (DP) and bis(2‐hydroxyethyl) terephthalate (BHT), and PET short fibers were used as inducers. The results showed that BHT was the best inducer. The BHT‐induced extracellular lipase could catalyze the hydrolysis of the PET model substrate DP. The formation of new carboxyl groups is consistent with the increase in K/S values of dyed PET fabrics after the enzymatic treatment. Additionally, treatment with the BHT‐induced lipase resulted in increased moisture regain and weight loss of PET fiber/fabric, while the water contact angle and the static half decay time decreased slightly. This indicates that hydrophilicity and anti‐static ability were improved after the treatment with the BHT‐induced lipase. Compounds that were solubilized by the enzymatic treatment were analyzed by spectrophotometry and high performance liquid chromatography (HPLC) with UV detection. Both analyses indicated that hydrolysis of PET occurred and that products were formed due to the catalytic action of the BHT‐induced enzyme; however, no significant changes in UV absorbance and no new peaks were found in HPLC‐UVD analyses of reaction mixtures with olive oil‐induced lipase or PET‐induced lipase. This investigation has resulted in detailed procedures for the production of PET‐hydrolyzing lipase by A. oryzae and is the first report regarding the successful use of BHT as an inducer for the enzyme production.
Stabilization of Membrane Proteins: the Case of G‐Protein‐Coupled Receptors
Authors: Reyes‐Alcaraz A. , Tzanov T. , Garriga P.
Published: July 2008

G‐protein‐coupled receptors are integral membrane proteins which constitute the largest family of signal transduction molecules participating in the majority of normal physiological processes. G‐protein‐coupled receptors are responsible for the control of enzyme activity, ion channels and vesicle transport, and they respond to a wide variety of stimuli, like signals involved in sensory systems such as vision, taste and olfaction, but also to a diverse set of chemical signals such as lipids, hormones, neurotransmitters, amino acids, nucleotides, peptides and proteins. This family of receptors is being widely studied because of its potential use as pharmacological targets in drug development, and recently also for its potential use in the development of novel biosensors. G‐protein‐coupled receptors are specifically designed to fold and function in a lipid bilayer environment, where these membrane proteins are remarkably stable and achieve their optimal performance. The currently used technology for the purification of G‐protein‐coupled receptors consists in their extraction from the cell membrane and solubilization into detergent micelles. A common drawback of this strategy is that G‐protein‐coupled receptors solubilized in typical detergents show rather poor conformational stability, which may result in relatively rapid inactivation. The poor stability of detergent‐solubilized samples renders many membrane proteins biochemically intractable. This precludes the determination of a high‐resolution structure and imposes severe limitations for the development of applications. Thus, the enhancement of the stability of G‐protein‐coupled receptors is a major issue in order to facilitate structural determination and to unravel their potential in biotechnological applications. This work provides a brief overview of some current advances in the experimental methods for stabilizing G‐protein‐coupled receptors that can also be extended to other types of membrane proteins.
In‐situ Enzymatic Generation of Hydrogen Peroxide for Bleaching Purposes
Authors: López C. , Cavaco‐Paulo A.
Published: July 2008

Bleaching detergent formulations contain environmentally unfriendly bleaching agents (perborates and percarbonates), which cause aquatic eutrophication, although without these compounds detergents are much less efficient for the washing processes. In an effort to replace these compounds, in this study, hydrogen peroxide was generated as a bleaching compound by means of enzymatic reactions. Three different pathways were investigated. The first one was the H2O2 production from glucose by glucose oxidase. The second one was the production of H2O2 from carboxymethylcellulose (CMC) by the action of both cellulase, which promotes the hydrolysis of the polymeric chain, and glucose oxidase, which oxidizes the smaller fractions to produce H2O2. Finally, H2O2 was also obtained from ethanol, which is present in liquid detergents, by the action of the enzyme alcohol oxidase. In the search for maximal peroxide production, substrate concentration and enzymatic activities were optimized. The effect of H2O2 produced in the washing process was simulated by means of a process of cotton bleaching. Although enzymatic‐reaction oxidations produced higher levels of hydrogen peroxide (up to 1 g/L after 8 h), higher improvement of cotton whiteness was achieved from CMC and from ethanol. The milder conditions of temperature and pH, biodegradability and less consumption of water and energy are advantageous for enzymes as good substitutes for H2O2 precursors and make them appropriate to be considered in detergent formulations. These enzymes could be combined with other oxidative enzymes, such as peroxidases, in order to lower the required temperature and use a pH close to the neutral value during the bleaching processes.
Biological Coloration of Flax Fabrics with Flavonoids using Laccase fromTrametes hirsuta
Authors: Kim S. , López C. , Güebitz G. , Cavaco‐Paulo A.
Published: July 2008

Biological environmentally friendly concepts are emerging to replace chemical treatments of fabrics. In this work, a new process for the coloration of flax fabrics via enzymatic oxidation of natural flavonoids (morin, quercetin) has been developed. Laccase fromTrametes hirsutais able to react with flavonoids and polymerize them, resulting in a strongly colored polymeric solution which can be applied to the coloration of flax fabrics. Two methods were investigated:(i)the simultaneous enzymatic polymerization and coloration of fabrics and(ii)the polymerization of flavonoids with laccase, followed by a further coloration of the flax fabrics. Factors such as temperature, reaction time, presence of NaCl or the use of bleached or unbleached fabrics were evaluated in order to increase the color of the fabrics and the color fastness. The increase of temperature, the presence of salt and the use of unbleached fabrics allowed the final color to be improved. Colorized flax fabrics with oxidized quercetin solution showed a color fixation two times higher than the fabrics colorized with oxidized morin. Finally, the polymerization of flavonoids and their binding to fibers were verified using Fourier transform infrared spectroscopy (FT‐IR). The results confirmed this environmentally friendly process as useful for the coloration of flax fabrics. A similar technique could also be extended to the treatment of other types of fabrics in textile processes.
Potential Applications of Oxidoreductases for the Re‐oxidation of Leuco Vat or Sulfur Dyes in Textile Dyeing
Authors: Xu F. , Salmon S.
Published: July 2008

Conventional textile dyeing by vat and sulfur dyes includes reduction and re‐oxidation steps (with chemical reductants and oxidants), so that the insoluble dyes can be solubilized in the dyeing solution, adsorbed by the fabric, and fixed onto the dyed fabric. The treatments often involve hazardous chemicals, expensive catalysts, or conditions that are suboptimally effective, energy‐intensive, caustic, or polluting. Improving these steps with enzyme technology could be of significant interest in terms of better dyeing, handling of hazardous chemicals, disposal of waste, or production economy. The idea of an enzymatic re‐oxidation step for vat and sulfur dyeings was tested under simplified laboratory conditions. Selected vat and sulfur dyes, including Vat Blue 43, Vat Orange 7, Vat Green 3, Vat Orange 2, Vat Red 13, Vat Yellow 2, and Sulfur Black 1, were first chemically reduced. The reduced (leuco) dyes were then re‐oxidized by aerated buffer solutions or H2O2, in the presence or absence of an oxidoreductase, selected from seven laccases from Myceliophthora thermophila, Scytalidium thermophilum, Coprinus cinereus, Trametes villosa, Rhizoctonia solani, Pycnoporus cinnabarinus, Botrytis cinerea, a bilirubin oxidase from Myrothecium verrucaria, and a heme peroxidase from Coprinus cineresu. It was shown that the enzymes were able to catalyze and accelerate the re‐oxidation of the reduced dyes, even when they were adsorbed on cotton fabric, by dissolved air (O2) or H2O2. Small redox‐active mediators could facilitate the enzymatic re‐oxidation. For Sulfur Black 1, a higher conversion of the leuco dye was achieved with laccase‐catalyzed re‐oxidation. The further development of this potential enzyme application is discussed.
Genotoxicity, cytotoxicity, and reactive oxygen species induced by single‐walled carbon nanotubes and C60 fullerenes in the FE1‐Muta™Mouse lung epithelial cells
Authors: Jacobsen Nicklas Raun , Pojana Giulio , White Paul , Møller Peter , Cohn Corey Alexander , Smith Korsholm Karen , Vogel Ulla , Marcomini Antonio , Loft Steffen , Wallin Håkan
Published: July 2008

Viability, cell cycle effects, genotoxicity, reactive oxygen species production, and mutagenicity of C60 fullerenes (C60) and single‐walled carbon nanotubes (SWCNT) were assessed in the FE1‐Muta™Mouse lung epithelial cell line. None of these particles induced cell death within 24 hr at doses between 0 and 200 μg/ml or during long‐term subculture exposure (576 hr) at 100 μg/ml, as determined by two different assays. However, cell proliferation was slower with SWCNT exposure and a larger fraction of the cells were in the G1 phase. Exposure to carbon black resulted in the greatest reactive oxygen species generation followed by SWCNT and C60 in both cellular and cell‐free particle suspensions. C60 and SWCNT did not increase the level of strand breaks, but significantly increased the level of FPG sensitive sites/oxidized purines (22 and 56%, respectively) determined by the comet assay. The mutant frequency in the cII gene was unaffected by 576 hr of exposure to either 100 μg/ml C60 or SWCNT when compared with control incubations, whereas we have previously reported that carbon black and diesel exhaust particles induce mutations using an identical exposure scenario. These results indicate that SWCNT and C60 are less genotoxic in vitro than carbon black and diesel exhaust particles. Environ. Mol. Mutagen., 2008. © 2008 Wiley‐Liss, Inc.
Effects of low dose radiation and vitamin C treatment on chloroquine‐induced genotoxicity in mice
Authors: Roy Lopamudra Das , Mazumdar Mehnaz , Giri Sarbani
Published: July 2008

Chloroquine (CHQ) is a commonly used antimalarial agent. We evaluated the genotoxic potential of CHQ using chromosome aberration (CA), micronucleus (MN), and sperm head abnormality (SA) assays in vivo in Swiss albino mice. The interaction between a low dose of radiation and CHQ, as well as the effect of vitamin C on CHQ‐induced genotoxicity, was also evaluated. It was observed that CHQ induced CA, as well as MN, in the bone marrow cells under certain treatment conditions. Further, CHQ induced significant increase in the frequency of SA both at 24 hr and 21 days of the treatment. In the present study vitamin C pretreatment apparently reduced the frequency of CA, MN, and SA induced by CHQ. In the combination studies with radiation and CHQ, we found that exposure to low doses of radiation (0.5 Gy) either prior to or following CHQ treatment, in the dose ranges tested, has little or no synergistic effect in the mutagenic evaluations in somatic cells. However, radiation exposure along with CHQ treatment resulted in significant increase in the frequency of SA as compared to the groups receiving CHQ alone at 21 days of the treatment. In summary, CHQ has the potential to induce genotoxicity in mammalian cells. Further, germ cells may be relatively more sensitive as compared to the somatic cells. Environ. Mol. Mutagen., 2008. © 2008 Wiley‐Liss, Inc.
Dynamic systems with high damping rubber: Nonlinear behaviour and linear approximation
Authors: Dall'Asta Andrea , Ragni Laura
Published: July 2008

High damping rubber (HDR) shows a quite complex constitutive behaviour, which is nonlinear with respect to strain and is dependent on the strain rate. In addition, it exhibits a transient response during which the material properties change (scragging or more generally the Mullins effect). A number of recent works were dedicated to analysing and modelling material behaviour. This paper studies the nonlinear dynamics of systems with restoring force produced by HDR‐based devices in order to propose a procedure to define equivalent linear models considering both transient and stationary behaviours. The reliability of these linear models is tested by evaluating the upper and lower bounds of the seismic response of a structural system equipped with HDR‐based devices (structural system with dissipative bracings and isolated systems). Copyright © 2008 John Wiley & Sons, Ltd.
Modelling exterior beam–column joints for seismic analysis of RC frame structures
Authors: Favvata Maria J. , Izzuddin Bassam A. , Karayannis Chris G.
Published: July 2008

In common practice, the local response of beam–column joints is not considered for the seismic analysis of multistorey reinforced concrete (RC) frame structures, where these critical regions are typically assumed as rigid. Studies that incorporate the local effect of the joints in the seismic analysis of multistorey RC frame structures are limited. Identifying the main disadvantages of the analytical models that have been proposed so far, a behavioural model is developed for the simulation of the local inelastic response of exterior RC beam–column joints in multistorey RC frame structure. Special attention is given to the description of the main characteristics of the actual seismic response of the joints, including strength and stiffness degradation. The proposed model is incorporated as a rotational spring element in a general program for nonlinear static and dynamic analysis of structures, and a procedure for the evaluation of the required model parameters is also presented. The effectiveness of the proposed joint element model is demonstrated through comparisons with experimental data of 12 RC exterior joints reported in the literature. Moreover, using the proposed element, the influence of the local nonlinear response of RC exterior beam–column joints on the ductility requirements of columns and on the failure mode and overall seismic response of a multistorey RC frame structure is investigated. From the results of these analyses, it is concluded that the modelling of exterior RC joints with reduced capacity as rigid joints can lead to unconservative results and therefore to unsafe design. Copyright © 2008 John Wiley & Sons, Ltd.
A stochastic ground motion model with separable temporal and spectral nonstationarities
Authors: Rezaeian Sanaz , Der Kiureghian Armen
Published: July 2008

A fully nonstationary stochastic model for strong earthquake ground motion is developed. The model employs filtering of a discretized white‐noise process. Nonstationarity is achieved by modulating the intensity and varying the filter properties in time. The formulation has the important advantage of separating the temporal and spectral nonstationary characteristics of the process, thereby allowing flexibility and ease in modeling and parameter estimation. The model is fitted to target ground motions by matching a set of statistical characteristics, including the mean‐square intensity, the cumulative mean number of zero‐level up‐crossings and a measure of the bandwidth, all expressed as functions of time. Post‐processing by a second filter assures zero residual velocity and displacement, and improves the match to response spectral ordinates for long periods. Copyright © 2008 John Wiley & Sons, Ltd.
Numerical simulation of reinforcement strengthening for high‐arch dams to resist strong earthquakes
Authors: Long Yuchuan , Zhang Chuhan , Jin Feng
Published: July 2008

This paper focuses on analyzing the nonlinear seismic response of high‐arch dams with cantilever reinforcement strengthening. A modified embedded‐steel model is presented to evaluate the effects of the strengthening measure on alleviating the extension and opening of cracks under strong earthquakes. By stiffening reinforced steel, this model can easily consider the steel–concrete interaction for lightly reinforced concrete (RC) members without the need of dividing them into RC and plain concrete zones. The new tensile constitutive relations of reinforced steel are derived from the load–deformation relationship of RC members in direct tension. This model has been implemented in the finite element code and its applicability is verified by two numerical simulations for RC tests. Subsequently, numerical analyses for a 210‐m high‐arch dam (Dagangshan arch dam) are conducted with and without the presence of cantilever reinforcement. Numerical results show that reinforcement strengthening can reduce the nonlinear response of the arch dam, e.g. joint opening and crest displacement, and limit the extension and opening width of concrete cracks. Copyright © 2008 John Wiley & Sons, Ltd.
Personal standards, self‐evaluation and perceived benefits of thinness in girls and young women with disturbed eating
Authors: Aila Gustafsson Sanna , Edlund Birgitta , Kjellin Lars , Norring Claes
Published: July 2008

The aim of this study was to examine personal standards, self‐evaluation and perceived benefits of thinness in Swedish females 14–21 years with disturbed eating (DE) and to compare these to a group with other psychosocial problems and to a symptom free group. Seventy subjects with DE‐group, 65 subjects with psychosocial problems and 70 symptom free subjects were compared regarding items selected from four questionnaires. High personal standards expressed in a competitive way were specific for the DE‐group. In comparison with the other groups the DE‐group also reported significantly more perceived benefits of thinness and they more frequently believed that thinness would make them more popular. The DE‐group also reported a more negative self‐evaluation, although this was a trait shared with the subjects with other psychosocial problems and consequently not specific for the DE‐group. Identifying specific factors that perpetuate DE habits is important in order to improve our understanding and enhance the treatment of eating disorders. Copyright © 2008 John Wiley & Sons, Ltd and Eating Disorders Association.
A numerical study of heat island flows: Stationary solutions
Authors: Dubois Thierry , Touzani Rachid
Published: July 2008

We present two‐dimensional numerical simulations of a natural convection problem in an unbounded domain. The flow circulation is induced by a heat island located on the ground and thermal stratification is applied in the vertical direction. The main effect of this stably stratified environment is to induce the propagation of thermal perturbations in the horizontal direction far from the local thermal source. Numerical stationary solutions at Ra⩽105 are computed in large elongated computational domains: convergence with respect to the domain sizes is investigated at different resolutions. On fine grids, with mesh size ${h} = {{1} \over {128}}$, a thermal sponge layer is added at the vertical boundaries: this local damping technique improves the convergence with respect to the domain length. Boussinesq equations are discretized with a second‐order finite volume scheme on a staggered grid combined with a second‐order projection method for the time integration. Copyright © 2008 John Wiley & Sons, Ltd.