bluuebunny/crossref_metadata_2025_split huggingface dataset:
Endo-anal ultrasound versus endo-anal magnetic resonance imaging for the depiction of external anal sphincter pathology in patients with faecal incontinence: a systematic review
Authors: Sajid MS , Khatri K , Siddiqui MRS , Baig MK 
Published: February 2010

Abstract

Objective: To evaluate the endo-anal ultrasound (EAUS) versus endo-anal magnetic resonance imaging (EAMRI) in the diagnosis of external anal sphincter defects (EAS) in patients with faecal incontinence (FI). Methods: Studies on EAUS and EAMRI were selected and analyzed to generate summative data. Results: Five studies encompassing 347 patients of FI were included in this review. Three studies validated the results of EAUS and EAMRI by surgery (61 patients). In the fixed effect model, EAUS was superior to EAMRI in the depiction of EAS defects. On combined analysis of five studies using fixed effect model, both EAUS and EAMRI were equally effective. However, there was a significant heterogeneity between studies. Conclusion: EAUS and EAMRI are comparable in the diagnosis of EAS defects in patients of FI. Since EAUS is an economical, quicker and easily available imaging modality, it may be used a preferable investigation for the diagnosis of EAS defects in patients of FI.
Flexible Silk–Inorganic Nanocomposites: From Transparent to Highly Reflective
Authors: Kharlampieva Eugenia , Kozlovskaya Veronika , Gunawidjaja Ray , Shevchenko Valeriy V. , Vaia Richard , Naik Rajesh R. , Kaplan David L. , Tsukruk Vladimir V. 
Published: February 2010

AbstractA novel type of all‐natural, biocompatible, and very robust nanoscale free‐standing biohybrids are reported. They are obtained by integrating a silk fibroin matrix with functional inorganic nanoplatelets using a spin‐assisted layer‐by‐layer assembly. The organized assembly of the silk fibroin with clay (montmorillonite) nanosheets results in highly transparent nanoscale films with significantly enhanced mechanical properties, including strength, toughness, and elastic modulus, as compared to those for the pristine silk nanomaterials. Moreover, replacing clay nanoplatelets with a highly reflective Langmuir monolayer of densely packed silver nanoplates causes a similar enhancement of the mechanical properties, but in contrast to the materials above, highly reflective, mirror‐like, nanoscale flexible films are created. This strategy offers a new perspective for the fabrication of robust all‐natural flexible nanocomposites with exceptional mechanical properties important for biomedical applications, such as reinforced tissue engineering. On the other hand, the ability to convert silk‐based nanoscale films into mirror‐like biocompatible flexible films can be intriguing for prospective photonics and optical exploitation of these nanobiohybrids.
Stable Anticancer Gold(III)–Porphyrin Complexes: Effects of Porphyrin Structure
Authors: Sun Raymond Wai‐Yin , Li Carrie Ka‐Lei , Ma Dik‐Lung , Yan Jessie Jing , Lok Chun‐Nam , Leung Chung‐Hang , Zhu Nianyong , Che Chi‐Ming 
Published: February 2010

AbstractIn the design of physiologically stable anticancer gold(III) complexes, we have employed strongly chelating porphyrinato ligands to stabilize a gold(III) ion [Chem. Commun. 2003, 1718; Coord. Chem. Rev. 2009, 253, 1682]. In this work, a family of gold(III) tetraarylporphyrins with porphyrinato ligands containing different peripheral substituents on the meso‐aryl rings were prepared, and these complexes were used to study the structure–bioactivity relationship. The cytotoxic IC50 values of [Au(Por)]+ (Por=porphyrinato ligand), which range from 0.033 to >100 μM, correlate with their lipophilicity and cellular uptake. Some of them induce apoptosis and display preferential cytotoxicity toward cancer cells than to normal noncancerous cells. A new gold(III)–porphyrin with saccharide conjugation [Au(4‐glucosyl‐TPP)]Cl (2 a; H2(4‐glucosyl‐TPP)=meso‐tetrakis(4‐β‐D‐glucosylphenyl)porphyrin) exhibits significant cytostatic activity to cancer cells (IC50=1.2–9.0 μM) without causing cell death and is much less toxic to lung fibroblast cells (IC50>100 μM). The gold(III)–porphyrin complexes induce S‐phase cell‐cycle arrest of cancer cells as indicated by flow cytometric analysis, suggesting that the anticancer activity may be, in part, due to termination of DNA replication. The gold(III)–porphyrin complexes can bind to DNA in vitro with binding constants in the range of 4.9×105 to 4.1×106 dm3 mol−1 as determined by absorption titration. Complexes 2 a and [Au(TMPyP)]Cl5 (4 a; [H2TMPyP]4+=meso‐tetrakis(N‐methylpyridinium‐4‐yl)porphyrin) interact with DNA in a manner similar to the DNA intercalator ethidium bromide as revealed by gel mobility shift assays and viscosity measurements. Both of them also inhibited the topoisomerase I induced relaxation of supercoiled DNA. Complex 4 a, a gold(III) derivative of the known G‐quadruplex‐interactive porphyrin [H2TMPyP]4+, can similarly inhibit the amplification of a DNA substrate containing G‐quadruplex structures in a polymerase chain reaction stop assay. In contrast to these reported complexes, complex 2 a and the parental gold(III)–porphyrin 1 a do not display a significant inhibitory effect (<10 %) on telomerase. Based on the results of protein expression analysis and computational docking experiments, the anti‐apoptotic bcl‐2 protein is a potential target for those gold(III)–porphyrin complexes with apoptosis‐inducing properties. Complex 2 a also displays prominent anti‐angiogenic properties in vitro. Taken together, the enhanced stabilization of the gold(III) ion and the ease of structural modification render porphyrins an attractive ligand system in the development of physiologically stable gold(III) complexes with anticancer and anti‐angiogenic activities.
Noncovalent Assembly of Picket‐Fence Porphyrins on Nitrogen‐Doped Carbon Nanotubes for Highly Efficient Catalysis and Biosensing
Authors: Tu Wenwen , Lei Jianping , Jian Guoqiang , Hu Zheng , Ju Huangxian 
Published: February 2010

AbstractA water‐insoluble picket‐fence porphyrin was first assembled on nitrogen‐doped multiwalled carbon nanotubes (CNx MWNTs) through FeN coordination for highly efficient catalysis and biosensing. Scanning electron micrographs, Raman spectra, X‐ray photoelectron spectra, UV/Vis absorption spectra, and electrochemical impedance spectra were employed to characterize this novel nanocomposite. By using electrochemical methods on the porphyrin at low potential in neutral aqueous solution, the presence of CNx MWNTs led to the direct formation of a high‐valent iron(IV)–porphyrin unit, which produced excellent catalytic activity toward the oxidation of sulfite ions. By using sulfite ions, a widely used versatile additive and preservative in the food and beverage industries, as a model, a highly sensitive amperometric biosensor was proposed. The biosensor showed a linear range of four orders of magnitude from 8.0×10−7 to 4.9×10−3 mol L−1 and a detection limit of 3.5×10−7 mol L−1 due to the highly efficient catalysis of the nanocomposite. The designed platform and method had good analytical performance and could be successfully applied in the determination of sulfite ions in beverages. The direct noncovalent assembly of porphyrin on CNx MWNTs provided a facile way to design novel biofunctional materials for biosensing and photovoltaic devices.
Synthesis and Photovoltaic Properties of Cyclopentadithiophene‐Based Low‐Bandgap Copolymers That Contain Electron‐Withdrawing Thiazole Derivatives
Authors: Jung In Hwan , Yu Jinyoung , Jeong Eunjae , Kim Jinseck , Kwon Sooncheol , Kong Hoyoul , Lee Kwanghee , Woo Han Young , Shim Hong‐Ku 
Published: February 2010

AbstractWe have synthesized four types of cyclopentadithiophene (CDT)‐based low‐bandgap copolymers, poly[{4,4‐bis(2‐ethylhexyl)‐4H‐cyclopenta[2,1‐b:3,4‐b′]dithiophene‐2,6‐diyl}‐alt‐(2,2′‐bithiazole‐5,5′‐diyl)] (PehCDT‐BT), poly[(4,4‐dioctyl‐4H‐cyclopenta[2,1‐b:3,4‐b′]dithiophene‐2,6‐diyl)‐alt‐(2,2′‐bithiazole‐5,5′‐diyl)] (PocCDT‐BT), poly[{4,4‐bis(2‐ethylhexyl)‐4H‐cyclopenta[2,1‐b:3,4‐b′]dithiophene‐2,6‐diyl}‐alt‐{2,5‐di(thiophen‐2‐yl)thiazolo[5,4‐d]thiazole‐5,5′‐diyl}] (PehCDT‐TZ), and poly[(4,4‐dioctyl‐4H‐cyclopenta[2,1‐b:3,4‐b′]dithiophene‐2,6‐diyl)‐alt‐{2,5‐di(thiophen‐2‐yl)thiazolo[5,4‐d]thiazole‐5,5′‐diyl}] (PocCDT‐TZ), for use in photovoltaic applications. The intramolecular charge‐transfer interaction between the electron‐sufficient CDT unit and electron‐deficient bithiazole (BT) or thiazolothiazole (TZ) units in the polymeric backbone induced a low bandgap and broad absorption that covered 300 nm to 700–800 nm. The optical bandgap was measured to be around 1.9 eV for PehCDT‐BT and PocCDT‐BT, and around 1.8 eV for PehCDT‐TZ and PocCDT‐TZ. Gel permeation chromatography showed that number‐average molecular weights ranged from 8000 to 14 000 g mol−1. Field‐effect mobility measurements showed hole mobility of 10−6–10−4 cm2 V−1 s−1 for the copolymers. The film morphology of the bulk heterojunction mixtures with [6,6]phenyl‐C61‐butyric acid methyl ester (PCBM) was also examined by atomic force microscopy before and after heat treatment. When the polymers were blended with PCBM, PehCDT‐TZ exhibited the best performance with an open circuit voltage of 0.69 V, short‐circuit current of 7.14 mA cm−2, and power conversion efficiency of 2.23 % under air mass (AM) 1.5 global (1.5 G) illumination conditions (100 mW cm−2).
Two Versatile and Parallel Approaches to Highly Symmetrical Open and Closed Natural Product‐Based Structures
Authors: Montenegro Héctor E. , Ramírez‐López Pedro , de la Torre María C. , Asenjo María , Sierra Miguel A. 
Published: February 2010

AbstractTwo parallel approaches for preparing diverse and highly symmetrical homohybrids derived from a series of mono‐ and diterpenes, steroids, and alkaloids are reported. Both procedures are based on the mono‐addition of bis(alkynyl) dilithium reagents to natural products having a carbonyl group to produce the corresponding alkynyl derivatives. The Glaser–Hay Cu‐promoted homocoupling of these alkynyl natural product mono‐adducts as well as the Huisgen Cu‐catalyzed azide–alkyne cycloaddition (CuAAC) reaction resulted in the synthesis of steroid‐, terpene‐, and alkaloid‐based homohybrid derivatives incorporating diverse spacers to join the natural product scaffolds. Straightforward entries to novel closed highly symmetrical and complex estrone‐based macrocyclic and cage architectures by means of the Glaser–Eglinton homocoupling and the CuAAC reaction have been devised.
Expression of the embryonal isoform (0N/3R) of the microtubule‐associated protein tau in the adult rat central nervous system
Authors: Bullmann Torsten , Härtig Wolfgang , Holzer Max , Arendt Thomas 
Published: February 2010

AbstractTau is a microtubule‐associated protein expressed predominantly in neurons. The transcript of the tau gene is alternatively spliced. Resulting isoforms contain three or four microtubule‐binding repeats. The shortest tau isoform contains only three repeats (3R) and is expressed at birth. Previous data on rodents suggested that this isoform is no longer expressed during adulthood. It is replaced by tau isoforms containing four repeats (4R). The adult 4R tau isoforms bind to microtubules with higher affinity than 3R tau isoforms. Therefore, this isoform switch may reflect a need for more dynamic microtubules during development. Recently, we observed in rats that the 3R tau isoform is transiently expressed in adult neurogenesis. Subsequently, we performed an immunohistochemical labeling of the 3R tau isoform on serial sections of the adult rat brain. Interestingly, the 3R tau isoform is not only expressed in neuronal precursor cells. It is also present in mature neurons of the olfactory bulb, magnocellular neurosecretory system, posterolateral hypothalamus, locus coeruleus, raphe nucleus, solitary nucleus, medial septum and diagonal band, olfactory tuberculus, and piriform/olfactory cortex. This expression pattern is similar to that observed for the polysialylated form of the neuronal cell adhesion molecule (PSA‐NCAM) and the microtubule‐associated proteins doublecortin and collapsin response mediating protein (CRMP‐4/TUC‐4/Ulip‐1), which are also highly expressed during early development. The retention of a juvenile phenotype in some neurons might be associated with a functionally significant neuronal plasticity. J. Comp. Neurol. 518:2538–2553, 2010. © 2010 Wiley‐Liss, Inc.
Optimized DNA hybridization detection on nanocolloidal particles by dielectrophoresis
Authors: Gagnon Zachary , Senapati Satyajyoti , Chang Hsueh‐Chia 
Published: February 2010

AbstractOligonucleotides of varying surface coverage are functionalized onto the surface of 100 nm silica particles and the corresponding hybridization reaction with target ssDNA is studied using dielectrophoresis (DEP). The measured DEP cross‐over frequency (cof) is found to be sensitive to the oligonucleotide surface conformation. Zeta potential and particle size measurements suggest that at low oligo surface concentrations, non‐specific binding of oligo to the particle surface prevents efficient hybridization. At high surface coverage, steric hindrance due to the fully stretched, tightly packed oligo conformation prevents diffusion of DNA molecules to the particle surface. The optimum surface coverage exists at intermediate coverage where the particle is found to be the least electrically conductive, and hence exhibits the lowest measured cof. A simple DEP cof measurement hence allows one to determine the optimal oligo surface coverage for increased hybridization efficiency and detection sensitivity.
Enhanced multi‐objective optimization of a dimpled channel through evolutionary algorithms and multiple surrogate methods
Authors: Husain Afzal , Lee Ki‐Don , Kim Kwang‐Yong 
Published: February 2010

AbstractUsing a multi‐objective evolutionary algorithm (MOEA) and enhanced surrogate approximations, the present study demonstrates the numerical analysis and optimization of staggered‐dimple channels. Two surrogates, the response surface approximation (RSA) model and the Kriging (KRG) model, are applied in light of the surrogate fidelity of the approximate analysis. An enhanced Pareto‐optimal front is obtained by performing local resampling of the Pareto‐optimal front, which provides relatively more accurate Pareto‐optimal solutions in the design space for each surrogate model. Three dimensionless design variables are selected, which are related to geometric parameters, namely, the channel height, dimple print diameter, dimple spacing, and dimple depth. Two objective functions are selected that are related to the heat transfer and pressure loss, respectively. The objective‐function values are numerically evaluated through Reynolds‐averaged Navier–Stokes analysis at the design points that are selected through the Latin hypercube sampling method. Using these numerical simulations two surrogates, viz, the RSA and Kriging models, are constructed for each objective function and a hybrid MOEA is applied to obtain the Pareto‐optimal front. For the particular implementation of surrogate models, it is observed that Pareto‐optimal predictions of the RSA model are better than those of the KRG model, whereas the KRG model predicts equally well at the off‐Pareto‐region (region away from the Pareto‐optimal solutions), which is not the case with the RSA model. The local resampling of the Pareto‐optimal front increases the fidelity of the approximate solutions near the Pareto‐optimal region. The ratios of the channel height to the dimple print diameter and of the dimple print diameter to the dimple pitch are found to be more sensitive along the Pareto‐optimal front than the ratio of the dimple depth to the print diameter. The decrease of the ratio of the channel height to the dimple diameter and the increase of the ratio of the dimple print diameter to the pitch lead to greater heat transfer at the expense of the pressure loss, whereas the ratio of the dimple depth to the print diameter is rather insensitive to Pareto‐optimal solutions. Pareto‐optimal solutions at higher values of the Nusselt number are associated with higher values of the pressure loss due to the increased recirculation, mixing of fluid and vorticity generation. Copyright © 2010 John Wiley & Sons, Ltd.
Thalamocortical sensorimotor circuit in multiple sclerosis: An integrated structural and electrophysiological assessment
Authors: Dell'Acqua Maria Luisa , Landi Doriana , Zito Giancarlo , Zappasodi Filippo , Lupoi Domenico , Rossini Paolo M. , Filippi Maria M. , Tecchio Franca 
Published: February 2010

AbstractDemyelination and axonal damage are pathologic hallmarks of multiple sclerosis (MS), leading to loss of neuronal synchronization, functional disconnection amongst brain relays, and clinical sequelae. To investigate these properties, the primary component of the sensorimotor network was analyzed in mildly disabled Relapsing‐Remitting MS patients without sensory symptoms at the time of the investigation. By magnetoencephalography (MEG), the recruitment pattern within the primary sensory (S1) and motor (M1) areas was estimated through the morphology of the early components of somatosensory evoked magnetic fields (SEFs), after evaluating the S1 responsiveness to sensory inputs from the contralateral arm. In each hemisphere, network recruitment properties were correlated with ispilateral thalamus volume, estimated by morphometric techniques upon high‐resolution 3D structural magnetic resonance images (MRI). S1 activation was preserved, whereas SEF morphology was strikingly distorted in MS patients, marking a disruption of primary somatosensory network patterning. An unbalance of S1–M1 dynamic recruitment was documented and correlated with the thalamic volume reduction in the left hemisphere. These findings support the model of MS as a disconnection syndrome, with major susceptibility to damage experienced by nodes belonging to more frequently recruited and highly specialized networks. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.
Abnormal water diffusivity in corticostriatal projections in children with Tourette syndrome
Authors: Govindan Rajkumar Munian , Makki Malek I. , Wilson Benjamin J. , Behen Michael E. , Chugani Harry T. 
Published: February 2010

AbstractThe fronto‐striato‐thalamic circuit has been implicated in the pathomechanism of Tourette Syndrome (TS). To study white and gray matter comprehensively, we used a novel technique called Tract‐Based Spatial Statistics (TBSS) combined with voxel‐based analysis (VBA) of diffusion tensor MR images in children with TS as compared to typically developing controls. These automated and unbiased methods allow analysis of cerebral white matter and gray matter regions. We compared 15 right‐handed children with TS (mean age: 11.6 ± 2.5 years, 12 males) to 14 age‐matched right‐handed healthy controls (NC; mean age: 12.29 ± 3.2 years, 6 males). Tic severity and neurobehavioral scores were correlated with FA and ADC values in regions found abnormal by these methods. For white matter, TBSS analysis showed regions of increased ADC in the corticostriatal projection pathways including left external capsule and left and right subcallosal fasciculus pathway in TS group compared to NC group. Within the TS group, ADC for the left external capsule was negatively associated with tic severity (r= −0.586, P = 0.02). For gray matter, VBA revealed increased ADC for bilateral orbitofrontal cortex, left putamen, and left insular cortex. ADC for the right and left orbitofrontal cortex was highly correlated with internalizing problems (r = 0.665; P = 0.009, r = 0.545; P = 0.04, respectively). Altogether, this analysis revealed focal diffusion abnormalities in the corticostriatal pathway and in gray matter structures involved in the fronto‐striatal circuit in TS. These diffusion abnormalities could serve as a neuroimaging marker related to tic severity and neurobehavioral abnormalities in TS subjects. Hum Brain Mapp, 2010. © 2010 Wiley‐Liss, Inc.
Tubulin tyrosine ligase like 12 links to prostate cancer through tubulin posttranslational modification and chromosome ploidy
Authors: Wasylyk Christine , Zambrano Alberto , Zhao Chunhua , Brants Jan , Abecassis Joseph , Schalken Jack A. , Rogatsch Hermann , Schaefer Georg , Pycha Armin , Klocker Helmut , Wasylyk Bohdan 
Published: February 2010

AbstractProstate cancer is a common cause of death, and an important goal is to establish the pathways and functions of causative genes. We isolated RNAs that are differentially expressed in macrodissected prostate cancer samples. This study focused on 1 identified gene, TTLL12, which was predicted to modify tubulins, an established target for tumor therapy. TTLL12 is the most poorly characterized member of a recently discovered 14‐member family of proteins that catalyze posttranslational modification of tubulins. We show that human TTLL12 is expressed in the proliferating layer of benign prostate. Expression increases during cancer progression to metastasis. It is highly expressed in many metastatic prostate cancer cell lines. It partially colocalizes with vimentin intermediate filaments and cellular structures containing tubulin, including midbodies, centrosomes, intercellular bridges and the mitotic spindle. Downregulation of TTLL12 affects several posttranslational modifications of tubulin (detyrosination and subsequent deglutamylation and polyglutamylation). Overexpression alters chromosomal ploidy. These results raise the possibility that TTLL12 could contribute to tumorigenesis through effects on the cytoskeleton, tubulin modification and chromosome number stability. This study contributes a step toward developing more selective agents targeting microtubules, an already successful target for tumor therapy.
Abrasion resistance of oxidized zirconium in comparison with CoCrMo and titanium nitride coatings for artificial knee joints
Authors: Galetz Mathias C. , Fleischmann Ernst W. , Konrad Christian H. , Schuetz Adelheid , Glatzel Uwe 
Published: February 2010

AbstractMost total knee replacement joints consist of a metal femoral component made from a cobalt‐chromium‐ molybdenum (CoCrMo)‐alloy and a tibial component with an ultrahigh molecular weight polyethylene (UHMWPE) bearing surface. Wear of the UHMWPE remains the primary disadvantage of these implants. The allergic potential ascribed to CoCrMo‐alloys is a further concern. Other metallic alloys with and without ceramic coatings are clinically used to avoid these problems. This study compared the mechanical surface properties of an oxidized zirconium alloy with those of cast and wrought CoCrMo and TiAlV6‐4. Additionally, the influence of a titanium nitride (TiN)‐plasma coating on the surface properties was investigated. The composition of the oxidized zirconium layer was analyzed. Micro‐ and macrohardness tests as well as adhesion tests were used to reveal material differences in terms of their abrasive wear potential in artificial joints. © 2010 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2010