bluuebunny/crossref_metadata_2025_split huggingface dataset:
Sox10 is required for Schwann‐cell homeostasis and myelin maintenance in the adult peripheral nerve
Authors: Bremer Magdalena , Fröb Franziska , Kichko Tatjana , Reeh Peter , Tamm Ernst R. , Suter Ueli , Wegner Michael 
Published: April 2011

AbstractThe transcription factor Sox10 functions during multiple consecutive stages of Schwann‐cell development in the peripheral nervous system (PNS). Although Sox10 continues to be expressed in mature Schwann cells of the adult peripheral nerve, it is currently unclear whether it is still functional. Here, we used a genetic strategy to selectively delete Sox10 in glia of adult mice in a tamoxifen‐dependent manner. The tamoxifen‐treated mice developed a severe peripheral neuropathy that was associated with dramatic alterations in peripheral nerve structure and function. Demyelination and axonal degeneration were as much evident as signs of neuroinflammation. Compound action potentials exhibited pathophysiological alterations. Sox10‐deleted Schwann cells persisted in the peripheral nerve, but did not exhibit a mature, myelinating phenotype arguing that Sox10 is rather required for differentiation and maintenance of the differentiated state than for survival. Our report is the first evidence that Sox10 is still essentially required for Schwann‐cell function in the adult PNS and establishes a useful model in which to study human peripheral neuropathies. © 2011 Wiley‐Liss, Inc.
Occurrence and formation of endogenous histidine hexa‐coordination in cold‐adapted hemoglobins
Authors: Merlino Antonello , Howes Barry D. , Prisco Guido di , Verde Cinzia , Smulevich Giulietta , Mazzarella Lelio , Vergara Alessandro 
Published: April 2011

AbstractSpectroscopic and crystallographic evidence of endogenous (His) ligation at the sixth coordination site of the heme iron has been reported for monomeric, dimeric, and tetrameric hemoglobins (Hbs) in both ferrous (hemochrome) and ferric (hemichrome) oxidation states. In particular, the ferric bis‐ histidyl adduct represents a common accessible ordered state for the β chains of all tetrameric Hbs isolated from Antarctic and sub‐Antarctic fish. Indeed, the crystal structures of known tetrameric Hbs in the bis‐His state are characterized by a different binding state of the α and β chains. An overall analysis of the bis‐histidyl adduct of globin structures deposited in the Protein Data Bank reveals a marked difference between hemichromes in tetrameric Hbs compared to monomeric/dimeric Hbs. Herein, we review the structural, spectroscopic and stability features of hemichromes in tetrameric Antarctic fish Hbs. The role of bis‐histidyl adducts is also addressed in a more evolutionary context alongside the concept of its potential physiological role. © 2011 IUBMB IUBMB Life, 63(5): 295–303, 2011
Polymerization of hemoglobins in Arctic fish: Lycodes reticulatus and Gadus morhua
Authors: Riccio Alessia , Mangiapia Gaetano , Giordano Daniela , Flagiello Angela , Tedesco Roberta , Bruno Stefano , Vergara Alessandro , Mazzarella Lelio , di Prisco Guido , Pucci Piero , Paduano Luigi , Verde Cinzia 
Published: April 2011

AbstractIn vitro, and possibly in vivo, hemoglobin polymerization and red blood cell sickling appear to be widespread in codfish. In this article, we show that the hemoglobins of the two Arctic fish Lycodes reticulatus and Gadus morhua also have the tendency to polymerize, as monitored by dynamic light scattering experiments. The elucidation of the primary structure of the single hemoglobin of the zoarcid L. reticulatus shows the presence of a large number of cysteyl residues in α and β chains. Their role in eliciting the ability to produce polymers was also addressed by MALDI‐TOF and TOF‐TOF mass spectrometry. The G.morhua globins are also rich in Cys, but unlike in L. reticulatus, polymerization does not seem to be disulfide driven. The widespread occurrence of the polymerization phenomenon displayed by hemoglobins of Arctic fish supports the hypothesis that this feature may bea response to stressful environmental conditions. © 2011 IUBMB IUBMB Life, 63(5): 346–354, 2011
Reaming debris as a novel source of autologous bone to enhance healing of bone defects
Authors: Bakker Astrid D. , Kroeze Robert Jan , Korstjens Clara , de Kleine Ruben H. , Frölke Jan Paul M. , Klein‐Nulend Jenneke 
Published: April 2011

AbstractReaming debris is formed when bone defects are stabilized with an intramedullary nail, and contains viable osteoblast‐like cells and growth factors, and might thus act as a natural osteoinductive scaffold. The advantage of using reaming debris over stem cells or autologous bone for healing bone defects is that no extra surgery is needed to obtain the material. To assess the clinical feasibility of using reaming debris to enhance bone healing, we investigated whether reaming debris enhances the healing rate of a bone defect in sheep tibia, compared to an empty gap. As golden standard the defect was filled with iliac crest bone. Bones treated with iliac crest bone and reaming debris showed larger callus volume, increased bone volume, and decreased cartilage volume in the fracture gap, and increased torsional toughness compared to the empty gap group at 3 weeks postoperative. In addition, bones treated with reaming debris showed increased torsional stiffness at 6 weeks postoperatively compared to the empty defect group, while bending stiffness was marginally increased. These results indicate that reaming debris could serve as an excellent alternative to iliac crest bone for speeding up the healing process in bone defects that are treated with an intramedullary nail. © 2011 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 2011.
Alkali metal atom‐aromatic ring: A novel interaction mode realizes large first hyperpolarizabilities of M@AR (M = Li, Na, and K, AR = pyrrole, indole, thiophene, and benzene)
Authors: Yu Guangtao , Huang Xu‐Ri , Chen Wei , Sun Chia‐Chung 
Published: April 2011

AbstractSeveral new electride compounds M@pyrrole (M = Li, Na, and K), Li@AR (AR = indole, thiophene, and benzene), Li@tryptophan and Li@serotonin were designed and investigated, which exhibit considerably large first hyperpolarizabilities (β0) (6705, 1116, 11399, 5781, 4808, 1536, 8106, and 9389 au, respectively) by comparison with their corresponding sole molecules pyrrole (β0 = 30 au), indole (104 au), thiophene (6 au), benzene (0 au), tryptophan (159 au) and serotonin (151 au), respectively. The computational results revealed that the interaction of the alkali metal atom with π‐conjugated aromatic ring (AR) is one effectively new approach to produce diffuse excess electron to get a large β0 value, which is advantageous for the design of the novel high‐performance NLO materials with π‐conjugated AR: alkali metal atoms doped nanomaterials and biomolecules. © 2011 Wiley Periodicals, Inc. J Comput Chem 2011
EDF phytolith analysis from Heying site, southeast China, Shang‐Zhou dynasties
Authors: Wu Yan , Wang Changsui 
Published: April 2011

AbstractIn this article, we propose to make morphotypological phytolith analysis of Heying site during Shang‐Zhou Period by two methods: measuring based on extended depth of focus (EDF) image and measuring directly under microscope, and then compare their results. The comparison shows that the results by these two methods match each other for paleoenvironmental and agricultural analysis. Results of two methods show that Heying site's environment should be warm and moist based on the predominance of some specific phytolith assemblages. The phytolith morpho‐types originated from crop plants also indicates that rice planting was the mainstay agricultural economy. In comparison, the morphotypological analysis method based on EDF image took only about 1/10 the time as the original method by directly measuring under microscope. Thus, we can process more samples and make a more thorough and systematic morphotypological phytolith analysis with the same amount of time. Furthermore, the constructed EDF image can also be archived for future examination and for education. The above experiments indicate that the morphotypological analysis method based on EDF image is very promising for phytolith analysis. Microsc. Res. Tech. 2011. © 2011 Wiley Periodicals, Inc.
Synthesis, insecticidal activities, and molecular docking studies of 1,5‐disubstituted‐1,3,5‐hexahydrotriazine‐2‐(N‐nitro)imines
Authors: Sun Chuan‐Wen , Wang Hai‐Feng , Zhu Jun , Yang Ding‐Rong , Jin Jia , Xing Jia‐Hua 
Published: April 2011

AbstractA series of novel neonicotinoids analogs were designed by modifying the pharmacophore of imidacloprid to 1,3,5‐hexahydrotriazine conjugated to nitroimine (NNO2) and introducing the phenyl or arylmethyl at the 5‐position, and their insecticidal activities were evaluated. Introducing a heterocyclic methyl at 5‐position increased the insecticidal activities, whereas other phenyl, phenylmethyl or phenylethyl substituents were unfavorable to activities. Molecular docking study was also performed to clarify the interactions of the most potent analog 1‐((6‐chloropyridin‐3‐yl)methyl)‐5‐(3‐pyridylmethyl)‐1,3,5‐hexahydrotriazine‐2‐(N‐nitro) imine (7s) with the target nicotinic acetylcholine receptor, which explained the structure‐activity relationships observed in vitro, and revealed further possibilities for insecticide development. J. Heterocyclic Chem., (2011).
Synthesis of dispiro[oxindole‐pyrrolidine]‐thiazolo[3,2‐a][1,3,5]triazines by 1,3‐dipolar cycloaddition
Authors: Li Xiaofang , Li Zhikui , Zheng Aiting , Li Guobin , Yu Xianyong , Yi Pinggui 
Published: April 2011

AbstractThe 1,3‐dipolar cycloaddition of an azomethine ylide generated by a decarboxylative route from sarcosine and isatin to 7‐arylmethylidene‐3‐aryl‐3,4‐dihydro‐2H‐thiazolo[3,2‐a][1,3,5]triazin‐6(7H)‐ones afforded novel dispiro[oxindole‐pyrrolidine]‐thiazolo[3,2‐a][1,3,5]triazines in moderate yields. The structures of the products were determined and characterized thoroughly by NMR, MS, IR, and elemental analysis. The results of experiment indicated that this 1,3‐dipolar cycloaddition proceeded with high stereoselectivity and regioselectivity. J. Heterocyclic Chem., (2011).
Extraction and preconcentration technique for triazole pesticides from cow milk using dispersive liquid–liquid microextraction followed by GC‐FID and GC‐MS determinations
Authors: Farajzadeh Mir Ali , Djozan Djavanshir , Mogaddam M. R. Afshar , Bamorowat Mehdi 
Published: April 2011

AbstractA simple and rapid dispersive liquid–liquid microextraction (DLLME) technique coupled with gas chromatography‐flame ionization detection (GC‐FID) and gas chromatography‐mass spectrometry (GC‐MS) was developed for the extraction, preconcentration, and analysis of triazole pesticides (penconazole, hexaconazole, tebuconazole, triticonazole, and difenoconazole) in cow milk samples. Initially to 5 mL milk sample, NaCl and acetonitrile were added as salting‐out agent and extraction solvent, respectively. After manual shaking, the mixture was centrifuged. In the presence of sodium chloride, a two‐phase system was formed: upper phase, acetonitrile containing triazole pesticides and lower phase, aqueous phase containing soluble compounds and the precipitated proteins. After the extraction of pesticides from milk, a portion of supernatant phase (acetonitrile) was removed, mixed with chloroform at microliter level and rapidly injected by syringe into 5 mL distilled water. In this process, triazole pesticides were extracted into fine droplets of chloroform (as extraction solvent). After centrifugation, the fine droplets of chloroform were sedimented in bottom of the conical test tube. Finally, GC‐FID and GC‐MS were used for the separation and determination of analytes in the sedimented phase. Some important parameters like type of solvent for extraction of pesticides from milk, salt amount, the volume of extraction solvent, etc., which affect the extraction efficiency, were completely studied. Under the optimum conditions, enrichment factors were in the range of 156–380. The linear ranges of calibration curves were wide and limits of detection (LODs) and limits of quantification (LOQs) were between 4–58 and 13–180 μg/L, respectively. This method is very simple and rapid, requiring <15 min for sample preparation.
Development of a rapid and convenient method to separate eight ginsenosides from Panax ginseng by high‐speed counter‐current chromatography coupled with evaporative light scattering detection
Authors: Shehzad Omer , Jin Ha In , Park Youmie , Wan Ha Young , Shik Kim Yeong 
Published: April 2011

AbstractGinsenosides exhibit diverse biological activities and are major well‐known components isolated from the radix of Panax ginseng C.A. Meyer. In the present work, a rapid and facile method for the separation and purification of eight ginsenosides from P. ginseng by high‐speed counter‐current chromatography coupled with evaporative light scattering detector (HSCCC‐ELSD) was successfully developed. The crude samples for HSCCC separation were first purified from ginseng extract using a macroporous resin; the extract was loaded onto a Diaion‐HP20 column and fractionated by methanol and water gradient elution. The ginsenosides‐protopanaxadiol (PPD) and protopanaxatriol (PPT) fractions were subsequently eluted with 65 and 80% methanol and water gradient elution, respectively. Furthermore, these two fractions were separated by HSCCC‐ELSD. The two‐phase solvent system used for separation was composed of chloroform/methanol/water/isopropanol at a volume ratio of 4:3:2:1. Each fraction obtained was collected and dried, yielding the following eight ginsenosides: Rg1, Re, Rf, Rh1, Rb1, Rc Rb2 and Rd. The purity of these ginsenosides was greater than 97% as assessed by HPLC‐ELSD, and their structures were characterized by electrospray‐ionization mass spectrometry (ESI‐MS) and nuclear magnetic resonance spectroscopy. This is the first report regarding the separation of the ginsenosides Rh1, Rb2 and Rc from P. ginseng by HSCCC.
Drugs of abuse and their metabolites in waste and surface waters by liquid chromatography‐tandem mass spectrometry
Authors: Pedrouzo Marta , Borrull Francesc , Pocurull Eva , Marcé Rosa Maria 
Published: April 2011

AbstractA solid‐phase extraction and liquid chromatography‐tandem mass spectrometry (SPE/LC‐MS‐MS) method was developed and validated for the simultaneous determination of nicotine, five drugs of abuse (morphine, cocaine, codeine, methadone, and 2‐ethylidene‐1,5‐dimethyl‐3,3‐diphenylpyrrolidine) and four metabolites (dihydrocodeine, 6‐acetylmorphine, 11‐nor‐carboxy‐Δ9‐tetrahydrocannabinol, and benzoylecgonine) in water samples. A Fused‐Core™ particle column was used as an alternative to sub‐2‐μm particles in chromatographic separations to work with low backpressures and high efficiencies in short analysis times. Drugs were extracted from waste and surface water with SPE using Oasis MCX cartridges. Electrospray (ESI) in positive and negative mode and tandem MS selected reaction monitoring mode were used for identification and quantification. Calibration by linear regression analysis with deuterated internal standards was used to compensate the matrix effects. Limits of detection were found as low as 0.5–1 ng/L (surface water) and 1–50 ng/L (wastewater). The method was applied to the analysis of different kinds of samples. Wastewater from a sewage treatment plant was collected from three sampling points (after primary, secondary, and tertiary treatments) for a week. The analysis of the samples revealed a significant presence of these drugs in samples from primary treatments, where maximum concentrations of nicotine (1105 ng/L) and benzoylecgonine (3336 ng/L) were found. Most of the compounds showed values between <LOQ and 52 ng/L after tertiary treatment. When surface waters from the Ebro River were analyzed, only benzoylecgonine showed levels between 19 and 35 ng/L.
Pretreatment swallowing assessment in head and neck cancer patients
Authors: Starmer Heather , Gourin Christine , Lua Lannah L. , Burkhead Lori 
Published: April 2011

AbstractObjectives/Hypothesis:To discuss patient variables associated with swallowing dysfunction in head and neck cancer (HNCA) patients prior to intervention.Study Design:Prospective, multi‐institutional cohort study.Methods:All patients included had newly diagnosed head and neck malignancies. Patients undergoing instrumental swallowing evaluations prior to oncologic management were included for analysis. Pretreatment Penetration Aspiration Scores (PAS) were analyzed by primary tumor site, tumor stage, and standard demographic variables.Results:The final study sample was comprised of 204 consecutive individuals with newly diagnosed HNCA. Patients with advanced primary tumor (T) stage laryngeal/hypopharyngeal tumors had higher mean PAS scores (5.18) in contrast to early stage larynx/hypopharynx (1.93), advanced stage oral cavity/oropharynx (2.24), and early stage oral cavity/oropharynx (1.54, P < .0001), indicative of poorer function. Age, race, and sex were not associated with PAS scores. Multivariate logistic regression revealed significantly poorer PAS scores in patients with advanced primary tumors (odds ration [OR] = 3.83, 95% confidence interval [CI], 1.84‐8.00, P < .0001) and laryngeal/hypopharyngeal primary site disease (OR = 3.04, 95% CI, 1.41‐6.54, P = .004), after controlling for all other variables.Conclusions:This series demonstrates that swallowing dysfunction in high‐risk patients may be present in the pretreatment state and should be considered when determining candidacy for organ preservation modalities. These data highlight the importance of instrumental swallowing evaluations prior to intervention, particularly for those individuals with advanced stage and/or laryngeal/hypopharyngeal tumors.
Cell Specific Peptide‐Conjugated Polysaccharide Nanogels for Protein Delivery
Authors: Shimoda Asako , Sawada Shin‐ichi , Akiyoshi Kazunari 
Published: April 2011

AbstractA cell specific peptide (Arg‐Gly‐Asp; RGD)‐modified nanogel was prepared and evaluated for its potential to act as a protein delivery carrier. A bovine serum albumin (BSA)/RGD‐modified nanogel complex was efficiently internalized into cells through integrin‐mediated endocytosis. Endosomal escape of the RGD‐modified nanogel was observed after 24 h incubation. The nanogel proved useful for targeted protein delivery.
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Microstructure Evolution and Dynamic Stages of Cold‐Crystallized Poly(trimethylene terephthalate) Revealed by Synchronous Fluorescence Scanning
Authors: Luo Wei‐ang , Liao Zhengfu , Yang Jin , Chen Xudong , Zheng Xindan , Mai Kancheng 
Published: April 2011

AbstractThe nonisothermal cold crystallization of PTT films is studied by means of SFS. Detailed information on the glass transition and different stages of crystallization is presented. Crystallization kinetics and activation energy obtained from SFS are in good agreement with values determined from DSC. The results show that SFS is a simple, sensitive, selective in situ method for determining structure/dynamics relationships during relaxation and crystallization of polymers. SFS overcomes the drawbacks of conventional methods and combines the advantages of resonance light scattering (high sensitivity) and fluorescence spectroscopy (a structural technique). It can provide detailed information about structural evolution at molecular level, in particular about cohesive entanglement of polymer chains.
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Synthesis of Heterobifunctional Hyperbranched Polyethylenes Tethered with Dual Acryloyl and 2‐Bromoisobutyryl Functionalities via One‐Pot Chain‐Walking Terpolymerization
Authors: Xu Yuanqing , Campeau Patrick , Ye Zhibin 
Published: April 2011

AbstractA one‐step synthesis of heterobifunctional hyperbranched polyethylenes covalently tethered with dual acryloyl and 2‐bromoisobutyryl functionalities at controllable contents is reported. It is achieved in one pot by chain‐walking terpolymerization of ethylene with two functional acrylate comonomers, 1,6‐hexanediol diacrylate and 2‐(2‐bromoisobutyryloxy) ethyl acrylate. The unique chain‐walking mechanism renders the hyperbranched polymer chain topology and its remarkable capability in incorporating acrylate comonomers enables the incorporation of both comonomers to give two valuable functionalities. The two comonomers exhibit nearly equal vinyl reactivity and are incorporated independently in the terpolymerization with their molar contents controlled by adjusting the comonomer feed concentrations. magnified image
When referring physicians and researchers disagree on equipoise: the TOTAL trial experience
Authors: Rodrigues H. C. M. L. , Deprest J. , Berg P. P. v. d. 
Published: April 2011

AbstractObjectiveIn this article, we reflect on whether randomized controlled trials (RCTs) are adequate for the clinical evaluation of maternal–fetal surgery for congenital diaphragmatic hernia (CDH), focusing on the role of patients' preferences in the setting up of research protocols, on the requirement of equipoise and on the concept of therapeutic misconception (TM).MethodWe describe the conception and setting up of the tracheal occlusion (TO) to accelerate lung growth trial and analyze the ethical dilemmas faced by the research team during that time.ResultsDepending on the view adopted regarding the scope of equipoise, there are two ways of dealing with patient's preferences concerning fetoscopic endoluminal TO and expectant management during pregnancy for CDH.ConclusionThe solution adopted for fetoscopic endoluminal tracheal occlusion (FETO) is justified by the extended period of time it has been available to patients before the start of the RCT. Strong patient and referring physician preferences do not entail a right to have FETO, since it is a procedure of yet unproven efficacy and safety. In the future, to avoid the dilemmas posed by the TM and in name of the right of future generations of patients to have access to treatment of proven safety and efficacy, researchers must be able to plan RCT in due time. Copyright © 2011 John Wiley & Sons, Ltd.
Preparation and characterization of PET/clay nanocomposites by melt compounding
Authors: Ghasemi Hesam , Carreau Pierre J. , Kamal Musa R. , Uribe‐Calderon Jorge 
Published: April 2011

AbstractPoly(ethylene terephthalate) (PET) nanocomposites were prepared via melt compounding using a twin‐screw extruder at 265°C. Three different types of organomodified clay were melt compounded with PET: a commercial ammonium‐modified silicate clay (Cloisite 30B) and specially prepared thermally stable phosphonium‐ and imidazolium‐modified montmorillonites. X‐ray diffraction, scanning electron microscopy, transmission electron microscopy (TEM), and thermogravimetric analysis were used to characterize and evaluate the quality of the nanocomposites. To obtain quantitative evaluation of the dispersion level in nanocomposites, statistical analysis of TEM micrographs was performed using a dispersion parameter, D0.1, based on free‐path spacing measurements. The results showed that the ammonium surfactant yielded the best intercalation results in nanocomposites. POLYM. ENG. SCI., 2011. © 2011 Society of Plastics Engineers