bluuebunny/crossref_metadata_2025_split huggingface dataset:
Conjoined twins: A worldwide collaborative epidemiological study of the International Clearinghouse for Birth Defects Surveillance and Research
Authors: Mutchinick Osvaldo M. , Luna‐Muñoz Leonora , Amar Emmanuelle , Bakker Marian K. , Clementi Maurizio , Cocchi Guido , da Graça Dutra Maria , Feldkamp Marcia L. , Landau Danielle , Leoncini Emanuele , Li Zhu , Lowry Brian , Marengo Lisa K. , Martínez‐Frías María‐Luisa , Mastroiacovo Pierpaolo , Métneki Julia , Morgan Margery , Pierini Anna , Rissman Anke , Ritvanen Annukka , Scarano Gioacchino , Siffel Csaba , Szabova Elena , Arteaga‐Vázquez Jazmín 
Published: October 2011

AbstractConjoined twins (CT) are a very rare developmental accident of uncertain etiology. Prevalence has been previously estimated to be 1 in 50,000 to 1 in 100,000 births. The process by which monozygotic twins do not fully separate but form CT is not well understood. The purpose of the present study was to analyze diverse epidemiological aspects of CT, including the different variables listed in the Introduction Section of this issue of the Journal. The study was made possible using the International Clearinghouse for Birth Defects Surveillance and Research (ICBDSR) structure. This multicenter worldwide research includes the largest sample of CT ever studied. A total of 383 carefully reviewed sets of CT obtained from 26,138,837 births reported by 21 Clearinghouse Surveillance Programs (SP) were included in the analysis. Total prevalence was 1.47 per 100,000 births (95% CI: 1.32–1.62). Salient findings including an evident variation in prevalence among SPs: a marked variation in the type of pregnancy outcome, a similarity in the proportion of CT types among programs: a significant female predominance in CT: particularly of the thoracopagus type and a significant male predominance in parapagus and parasitic types: significant differences in prevalence by ethnicity and an apparent increasing prevalence trend in South American countries. No genetic, environmental or demographic significant associated factors were identified. Further work in epidemiology and molecular research is necessary to understand the etiology and pathogenesis involved in the development of this fascinating phenomenon of nature. © 2011 Wiley Periodicals, Inc.
Synthesis, characterization, and properties of long‐chain branched poly(butylene succinate)
Authors: Wang Guoli , Guo Baohua , Li Rui 
Published: October 2011

AbstractLong‐chain branched poly(butylene succinate) were synthesized through a two‐step process of esterification and polycondensation, using 1,2,4‐butanetriol (1,2,4‐BT) as a long‐chain branching agent. The effect of long‐chain branches on the crystallization behaviors, rheological properties, and tensile properties was investigated systematically. The results of differential scanning calorimetry and polarized optical microscopy showed that with the increasing of 1,2,4‐BT segments, the crystallization temperatures and glass transition temperatures increase slightly, while the relative crystallinity degree decreases gradually. Also, the double‐banded extinction patterns with periodic distance along the radial direction were observed in the spherulites of long‐chain branched poly(butylene succinate), similar to that of linear poly(butylene succinate) (PBS). The result of wide‐angle X‐ray diffraction indicated that the incorporation of 1,2,4‐BT segments had little effect on the crystal structure of PBS. However, based on data from rheology and tensile testing, the viscoelastic properties of long‐chain branched PBS under shear flow were different from the linear PBS. For example, the complex viscosities, storage modulus, and loss modulus of long‐chain branched PBS at low frequency were significantly enhanced in comparison with those of linear PBS. In addition, long‐chain branched PBS showed higher tensile strength than that of linear PBS without notable decrease in the elongation at break when compared with linear PBS. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012
Comparison of parameter‐adapted segmentation methods for fluorescence micrographs
Authors: Held Christian , Palmisano Ralf , Häberle Lothar , Hensel Michael , Wittenberg Thomas 
Published: October 2011

AbstractInterpreting images from fluorescence microscopy is often a time‐consuming task with poor reproducibility. Various image processing routines that can help investigators evaluate the images are therefore useful. The critical aspect for a reliable automatic image analysis system is a robust segmentation algorithm that can perform accurate segmentation for different cell types. In this study, several image segmentation methods were therefore compared and evaluated in order to identify the most appropriate segmentation schemes that are usable with little new parameterization and robustly with different types of fluorescence‐stained cells for various biological and biomedical tasks. The study investigated, compared, and enhanced four different methods for segmentation of cultured epithelial cells. The maximum‐intensity linking (MIL) method, an improved MIL, a watershed method, and an improved watershed method based on morphological reconstruction were used. Three manually annotated datasets consisting of 261, 817, and 1,333 HeLa or L929 cells were used to compare the different algorithms. The comparisons and evaluations showed that the segmentation performance of methods based on the watershed transform was significantly superior to the performance of the MIL method. The results also indicate that using morphological opening by reconstruction can improve the segmentation of cells stained with a marker that exhibits the dotted surface of cells. © 2011 International Society for Advancement of Cytometry
Utility of Screen Printed Electrodes for in Vitro Metabolic Stability Assays: Application to Acetaminophen and its Thioconjugates
Authors: Kauffmann Jean‐Michel , Van Antwerpen Pierre , Sarakbi Ahmad , Feier Bogdan , Tarik Sidali , Aydogmus Zeynep 
Published: October 2011

AbstractScreen printed electrodes (SPEs), in addition to their utility in the electrochemical quantification of compounds of pharmacological interest may be used (i) for studying the redox pattern of drug candidates by cyclic voltammetry, (ii) for electrochemical synthesis in microvolumes (microelectrosynthesis) at a selected applied potential with subsequent off‐line LC‐MS identification of the generated products, and (iii) for monitoring enzymatic reactions in microvolumes of samples. The resulting data are of valuable predictive value for in vitro metabolic stability assays. Acetaminophen (APAP) was used as relevant model drug compound to illustrate potential applications of SPEs in pharmaceutical research. The electrooxidation of APAP was studied, in the absence and presence of endogenous thiols, in microvolume sample by cyclic voltammetry and by microelectrolysis at a carbon based SPE (CSPE) and the generated products were identified off‐line by liquid chromatography coupled to mass spectrometry (LC‐MS).
A competent extraction method of plant proteins for 2‐D gel electrophoresis
Authors: Ashoub Ahmed , Berberich Thomas , Beckhaus Tobias , Brüggemann Wolfgang 
Published: October 2011

AbstractThe efficient extraction of high‐quality proteins is a key factor for a successful proteomic analysis approach. In the method suggested here, absolute ethanol containing 10 mM DTT was used to precipitate the proteins in plant tissue homogenates followed by their resuspension in a urea‐/thiourea‐ and NP‐40‐containing solution. Protein profiles were examined on pH 3–11 non‐linear IEF strips and SDS‐PAGE and compared with extracts using the established method of acetone‐10% TCA/0.07% 2‐mercaptoethanol precipitation (V. Méchin et al., Methods Mol. Biol. 2006, 355, 1–8). In addition to protein profile similarity for the two extracts, the acidic part of the acetone containing 10% TCA/0.07% 2‐mercaptoethanol extraction showed protein spots with high molecular weight in the range of 250–150 kDa, while the ethanol containing 10 mM DTT extracts indicated extra proteins spots at the basic part of the gels with molecular weights in the range of 25–15 kDa. The MALDI‐TOF‐MS of differential spots from acetone containing 10% TCA/0.07% 2‐mercaptoethanol precipitation method and absolute ethanol containing 10mM DTT indicated no similarity, ruling out the possibility that the two clusters shown represent identical proteins. The described method is easy in implementation, chemicals used are less toxic and proteins are easier to resuspend therefore presents an additional choice to implement towards finding the optimum method for extraction.
Electrophoretic isolation of saponin fractions from Saponinum album and their evaluation in synergistically enhancing the receptor‐specific cytotoxicity of targeted toxins
Authors: Thakur Mayank , Weng Alexander , Bachran Diana , Riese Sebastian B. , Böttger Stefan , Melzig Matthias F. , Fuchs Hendrik 
Published: October 2011

AbstractSaponinum album (SA) is a commercial mixture of saponins isolated from Gypsophila species. In the previously published work, we reported that SA dramatically improves the inhibition of tumor growth by targeted toxins in mice in a synergistic way. Here we report a simplified electrophoretic method for the isolation of a highly effective fraction of SA with a relative electrophoretic mobility to the dye front (Rf) of 0.63 from the mixture. In total, four different fractions were separated at a preparative scale, and evaluated by ESI‐MS, HPLC and TLC analysis. Electrophoretic mobility and electrochemical properties of the different fractions of saponins from SA were set into relation to their ability to enhance the cytotoxicity of epidermal growth factor (EGF)‐based targeted toxins. We here treated HER‐14 cells, which are NIH‐3T3 Swiss mouse embryo cells transfected with the human EGF receptor. Untransfected NIH‐3T3 cells served as control. The major bulk of SA (72.3%) (Rf=0.78) migrated the farthest and was found to be significantly ineffective (p<0.05) in enhancing the cytotoxicity of the targeted toxin, while the second fraction (Rf=0.63) showed an enhancement of 9800‐fold. The third (Rf=0.56) had an enhancement factor of 3200, the fourth (Rf=0.08) was again significantly ineffective (p<0.05) in exhibiting any enhancement of cytotoxicity.
Anion separations with pressure‐assisted capillary electrophoresis using a sequential injection analysis manifold and contactless conductivity detection
Authors: Mai Thanh Duc , Hauser Peter C. 
Published: October 2011

AbstractIt is demonstrated that a hydrodynamic flow superimposed on the mobility of analyte anions can be used for the optimization of analysis time in capillary zone electrophoresis. It was also possible to use the approach for counter‐balancing the electroosmotic flow and this works as well as the use of surface modifiers. To avoid any band‐broadening due to the bulk flow narrow capillaries of 10 μm internal diameter were employed. This was enabled by the use of capacitively coupled contactless conductivity detection, which does not suffer from the downscaling, and detection down to between 1 and 20 μM for a range of inorganic and small organic anions was found feasible. Precisely controlled hydrodynamic flow was generated with a sequential injection manifold based on a syringe pump. Sample injection was carried out with a new design relying on a simple piece of capillary tubing to achieve the appropriate back‐pressure for the required split‐injection procedure.
Aqueous suspension methods of carbon-based nanomaterials and biological effects on model aquatic organisms
Authors: Gao Jie , Llaneza Veronica , Youn Sejin , Silvera-Batista Carlos A. , Ziegler Kirk J. , Bonzongo Jean-Claude J. 
Published: October 2011

Abstract
The preparation of aqueous suspensions of carbon-based nanomaterials (NMs) requires the use of dispersing agents to overcome their hydrophobic character. Although studies on the toxicity of NMs have focused primarily on linking the characteristics of particles to biological responses, the role of dispersing agents has been overlooked. This study assessed the biological effects of a number of commonly used dispersing agents on Pseudokirchneriella subcapitata and Ceriodaphnia dubia as model test organisms. The results show that for a given organism, NM toxicity can be mitigated by use of nontoxic surfactants, and that a multispecies approach is necessary to account for the sensitivity of different organisms. In addition to the intrinsic physicochemical properties of NMs, exposure studies should take into account the effects of used dispersing fluids. Environ. Toxicol. Chem. 2012;31:210–214. © 2011 SETAC
Impact of carbon nanotube morphology on phenanthrene adsorption
Authors: Apul Onur Guven , Shao Ting , Zhang Shujuan , Karanfil Tanju 
Published: October 2011

Abstract
The present study examined the roles of the specific surface area (SSA), diameter, and length of carbon nanotubes (CNT) on the adsorption of phenanthrene (PNT) by analyzing the adsorption isotherms obtained with several single-walled carbon nanotubes (SWNT) and multiwalled carbon nanotubes (MWNT). At low equilibrium concentrations (e.g., 1 ppb), MWNTs with larger outer diameters exhibited higher PNT adsorption capacity on an SSA basis than those with smaller diameters. With increasing equilibrium concentration, adsorption on an SSA basis became independent of MWNT diameter, and the total surface area controlled maximum adsorption capacity. A similar analysis for the adsorption of naphthalene, a planar molecule with one less benzene ring but 20 times higher solubility than PNT, showed no correlation with respect to MWNT outer diameter. The results indicated that the surface curvature of MWNT was more important on the adsorption of PNT than on the adsorption of naphthalene. Specific surface area normalized isotherms did not show a correlation between PNT adsorption and lengths of SWNTs and MWNTs. Characterization results indicated that the morphology of CNTs plays an important role on the SSA and pore volume. Data from the manufacturer may not always represent the characteristics of CNTs in a particular batch. Therefore, accurate characterization of CNTs is critical to systematically examine the behavior of CNTs, such as adsorption and transport, in environmental systems. Environ. Toxicol. Chem. 2012;31:73–78. © 2011 SETAC
Correlation between Different Hand Force Assessment Methods from an Epidemiological Study
Authors: Coelho Denis A. , Harris‐Adamson Carisa , Lima Tânia M. , Janowitz Ira , Rempel David M. 
Published: October 2011

AbstractThis article presents the outcome of correlation analyses of data results obtained from using different methods for objectively and subjectively assessing hand force from a prospective study of 450 blue‐collar workers from several companies and industries, followed for up to 3 years. The study collected detailed ergonomic exposure data at baseline and upper extremity health outcome data at baseline and every 4 months during the study. Ultimately, the study was intended to evaluate dose‐response relationships of specific upper extremity disorders with detailed physical and psychosocial exposure data at the workplace while controlling for important individual factors. This article presents the methods used to collect data, as well as the hand force results of the epidemiological study in aggregate correlated form, as a means of exploring the degree of independence between the variables considered. These insights are useful in identifying musculoskeletal disorder (MSD) causation and predicting MSD risk based on work exposures. An enhanced understanding of the independence of MSD causal factors is instrumental in establishing more accurate multivariable models of MSD causation that will play an important role in extrapolating from the understanding of mechanisms of causation to establishing effective recommendations and programs to prevent the occurrence of MSDs. © 2011 Wiley Periodicals, Inc.
Affecting osteoblastic responses with in vivo engineered potato pectin fragments
Authors: Kokkonen Hanna , Verhoef Renè , Kauppinen Kyösti , Muhonen Virpi , Jørgensen Bodil , Damager Iben , Schols Henk A. , Morra Marco , Ulvskov Peter , Tuukkanen Juha 
Published: October 2011

AbstractPectins, complex plant‐derived polysaccharides, are novel candidates for biomaterial nanocoatings. Pectic rhamnogalacturonan‐I regions (RG‐I) can be enzymatically treated to so‐called modified hairy regions (MHR). We surveyed the growth and differentiation of murine preosteoblastic MC3T3‐E1 cells on Petri dishes coated with RG‐Is from native or genetically engineered potato tubers. Uncoated tissue culture polystyrene (TCPS) and aminated (AMI) dishes served as controls. MHRPTR_GAL sample was depleted of galactose (9 mol % galactose; 23 mol % arabinose) and MHRPTR_ARA of arabinose (61 mol % galactose; 6 mol % arabinose). Wild‐type (modified hairy region from potato pectin (MHRP)_WT) fragment contained default amounts (58 mol % galactose; 13 mol % arabinose) of both sugars. Focal adhesions (FAs) indicating cellular attachment were quantified. Reverse transcriptase polymerase chain reaction (RT‐PCR) of alkaline phosphatase and osteocalcin genes indicating osteoblastic differentiation was performed along with staining the produced calcium with tetracycline as an indicator of osteoblastic differentiation. Osteoblasts proliferated on all the samples to some extent. The control surfaces performed better than any of the pectin samples, of which the MHRP_WT seemed to function best. FA length was greater on MHRPTR_GAL than on other pectin samples, otherwise the mutants did not significantly deviate. RT‐PCR results indicate that differences between the samples at the gene expression level might be even subtler. However, tetracycline‐stained calcium‐containing mineral was detected merely only on uncoated TCPS. These results indicate the possibility to affect bone cell growth with in vivo‐modified pectin fragments, consecutively providing information on the significance of certain monosaccharides on the biocompatibility of these polysaccharides. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2012.
Ultrastructural analysis of human bone marrow mesenchymal stem cells during in vitro osteogenesis and chondrogenesis
Authors: Teti Gabriella , Cavallo Carola , Grigolo Brunella , Giannini Sandro , Facchini Andrea , Mazzotti Antonio , Falconi Mirella 
Published: October 2011

AbstractThe main purpose of this article was to describe the morphology of mesenchymal stem cells (MSCs) differentiated in vitro towards osteogenic and chondrogenic lineages and to focus on the ultrastructural features associated with these processes. Human mononuclear cells (hMNC) were isolated, expanded, and analyzed for the expression of specific cell surface markers to demonstrate their stem cell characteristics. Human mononuclear cells were differentiated in vitro in an osteogenic and in a chondrogenic sense for 7, 14, 21, and 28 days. Subsequently, they were processed using electron microscopic analysis (FEISEM). Alizarin red and alcian blue staining were carried out to demonstrate the deposition of mineral salts and proteoglycans in the extracellular matrix. Undifferentiated MSCs showed a cell surface covered by filopodia and ondulopodia. During differentiation, the MSCs changed their shape from a round to a fibroblastic‐like shape. At the end of the differentiation, several filaments with a parallel orientation in the osteogenic samples as well as a network organization in the chondrogenic samples were detected in the extracellular spaces. This study demonstrated that there are morphological features associated with the undifferentiated and differentiated states of the MSCs, which could be utilized as new parameters for identifying and classifying these cells. Microsc. Res. Tech., 2012. © 2011 Wiley Periodicals, Inc.
Impaired regional left ventricular strain after repair of tetralogy of fallot
Authors: Ordovas Karen G. , Carlsson Marcus , Lease Katy E. , Foster Elyse , Meadows Alison K. , Martin Alastair J. , Hope Michael , Do Loi , Higgins Charles B. , Saeed Maythem 
Published: October 2011

AbstractPurpose:To test the potential of magnetic resonance imaging (MRI) in early detection of left ventricular (LV) dysfunction in patients with pulmonary regurgitation and normal LV ejection fraction after repair of tetralogy of Fallot.Materials and Methods:Patients (n = 18) with repaired tetralogy of Fallot and pulmonary regurgitation were prospectively recruited. Healthy volunteers (n = 10) were used as control. Tagging MR images were acquired at the base, mid, and apical LV levels for assessing segmental rotation and circumferential strain. Cine MR images and velocity‐encoded MR images were also acquired for assessment of biventricular volumes and biventricular function and pulmonary regurgitant fraction, respectively. Mean values were compared between groups using unpaired Student's t‐test.Results:Patients presented with preserved global LV function (LVEF of 59 ± 5%). A significant decrease in LV peak circumferential strain was seen in patients compared with normal volunteers at the basilar (−15.6 ± 4.5% vs. −17.6 ± 4.4%; P < 0.01) and apical (−14.4± 6.1% vs. −17.3± 5.1%, P < 0.01) slices. LV peak rotation was also delayed in patients compared with volunteers at the basilar (6.1 ± 2.6° vs. 4.2 ± 0.6°; P < 0.01) and mid (8.0 ± 1.7° vs. 4.9 ± 1.0°; P < 0.01) slices.Conclusion:MRI can detect early regional LV dysfunction in patients with preserved LVEF after repair of tetralogy of Fallot. MR may be a useful technique for guiding clinical decisions in these patients in order to prevent future global LV deterioration. J. Magn. Reson. Imaging 2012;35:79‐85. © 2011 Wiley Periodicals, Inc.
Characterization of adrenal lesions using chemical shift MRI: Comparison between 1.5 tesla and two echo time pair selection at 3.0 tesla MRI
Authors: Nakamura Shinichi , Namimoto Tomohiro , Morita Kosuke , Utsunomiya Daisuke , Oda Seitaro , Nakaura Takeshi , Hirai Toshinori , Yamashita Yasuyuki 
Published: October 2011

AbstractPurpose:To compare chemical shift MRI obtained at 1.5 Tesla (T) and two pairs of echo time (TE) in‐phase and opposed‐phase 3.0T MRI to assess their usefulness for the differentiation between adrenal adenomas and non‐adenomas.Materials and Methods:We evaluated 91 adrenal masses (75 adenomas, 16 non‐adenomas) in 85 patients. The MR imaging parameters were: T1‐dual‐gradient‐echo(GRE) [echo times (TEs) = 1.1/2.3 ms (first‐echo‐pair) or 3.5/4.6 ms (second‐echo‐pair)] at 3.0T, and T1‐dual‐GRE (TEs = 2.4/4.8 ms) at 1.5T. Scans were quantitatively assessed for the signal intensity (SI) index, calculated as [(SIin‐phase‐SIopposed‐phase)/(SIin‐phase)] × 100(%). To test for differences between adenomas and non‐adenomas, we performed quantitative analysis and analysis of variance.Results:For all images, the SI index differed significantly between adenomas and non‐adenomas. The sensitivity /specificity of SI index at the first‐echo‐pair of 3.0T was 100%/ 100%, that of 95.6%/ 100% at the second‐echo‐pair of 3.0T, and 91.7%/ 88.9% at 1.5T, respectively. At intra‐individual comparisons, the SI indices obtained with the second‐echo‐pair at 3.0T were significantly lower than on the first‐echo‐pair at 3.0T and 1.5T.Conclusion:Chemical shift MRI at 3.0T provides more accurate differentiation between adenomas and non‐adenomas than at 1.5T. The SI index of the first‐echo‐pair at 3.0T is the most reliable evaluation method for differentiating adrenal adenomas from non‐adenomas. J. Magn. Reson. Imaging 2012;35:95‐102. © 2011 Wiley Periodicals, Inc.