bluuebunny/crossref_metadata_2025_split huggingface dataset:
Notch gain of function inhibits chondrocyte differentiation via Rbpj-dependent suppression of Sox9
Authors: Chen Shan , Tao Jianning , Bae Yangjin , Jiang Ming-Ming , Bertin Terry , Chen Yuqing , Yang Tao , Lee Brendan 
Published: September 2012

Abstract
Notch signaling plays a critical role during development by directing the binary cell fate decision between progenitors and differentiated cells. Previous studies have shown sustained Notch activation in cartilage leads to chondrodysplasia. Genetic evidence indicates that Notch regulates limb bud mesenchymal stem cell differentiation into chondrocytes via an Rbpj-dependent Notch pathway. However, it is still unknown how Notch governs chondrogenesis in the axial skeleton where Notch serves a primary patterning function. We hypothesized that both Rbpj-dependent and Rbpj-independent Notch signaling mechanisms might be involved. Cartilage-specific Notch gain-of-function (GOF) mutant mice display chondrodysplasia accompanied by loss of Sox9 expression in vertebrae. To evaluate the contribution of an Rbpj-dependent Notch signaling to this phenotype, we deleted Rbpj on the Notch GOF background. These mice showed persistent spine abnormalities characterized by “butterfly” vertebrae suggesting that removal of Rbpj does not fully rescue the axial skeleton deformities caused by Notch GOF. However, Sox9 protein level was restored in Rbpj-deficient Notch GOF mice compared with Notch GOF mutants, demonstrating that regulation of Sox9 expression is canonical or Rbpj-dependent. To further understand the molecular basis of this regulation, we performed chromatin immunoprecipitation (ChIP) assays and detected the recruitment of the Rbpj/NICD transcription complex to Rbpj-binding sites upstream of the Sox9 promoter. The association of the Rbpj/NICD complex with the Sox9 promoter is associated with transcriptional repression of Sox9 in a cellular model of chondrocyte differentiation. Hence, Notch negatively regulates chondrocyte differentiation in the axial skeleton by suppressing Sox9 transcription, and Rbpj-independent Notch signaling mechanisms may also contribute to axial skeletogenesis. © 2013 American Society for Bone and Mineral Research.
Activin A is essential for Feeder‐free culture of human induced pluripotent stem cells
Authors: Tomizawa Minoru , Shinozaki Fuminobu , Sugiyama Takao , Yamamoto Shigenori , Sueishi Makoto , Yoshida Takanobu 
Published: September 2012

AbstractFeeder‐free culture of human induced pluripotent stem (hiPS) cells is necessary for their clinical application to avoid adverse effects of foreign proteins. hiPS cells were cultured with combinations of activin (A), CHIR99021 (C), basic fibroblast growth factor (F), and leukemia inhibitory factor (L) under feeder‐free conditions. Culture was terminated after 12 passages or when the cell morphology changed from pluripotency. Pluripotency was analyzed by alkaline phosphatase (ALP) staining and immunostaining with antibodies to Oct3/4, Nanog, SSEA4, and TRA‐1‐60. SB431542 (SB), an activin inhibitor, was added to the culture, and the morphology of the cells was observed. hiPS cells cultured with A, AC, and ACL after 12 passages were positive for ALP staining. Oct3/4 was positive in hiPS cells cultured with A, AC, and ACL. hiPS cells were positive for Nanog when cultured with A and AC; however, Nanog signal was weaker in cells cultured with ACL. SSEA4 was positive in hiPS cells cultured with A and AC but almost negative in those cultured with ACL. hiPS cells were positive for TRA‐1‐60 when cultured with A, AC, and ACL. hiPS cells lose their undifferentiated morphology at six passages when cultured with A + SB, five passages with AC + SB, and nine passages with ACL. We conclude that feeder‐free culture of hiPS cells requires A or AC to maintain pluripotency. J. Cell. Biochem. 114: 584–588, 2013. © 2012 Wiley Periodicals, Inc.
SUMOylation of ATF3 alters its transcriptional activity on regulation of TP53 gene
Authors: Wang Chiung‐Min , Brennan Victoria C. , Gutierrez Ninoska M. , Wang Xirui , Wang Lizhong , Yang Wei‐Hsiung 
Published: September 2012

AbstractCyclic AMP‐dependent transcription factor‐3 (ATF3), a stress sensor, plays an essential role in cells to maintain homeostasis and has diverse functions in cellular survival and death signal pathways. ATF3 is a novel regulator of p53 protein stability and function. The activities of ATF3 are modulated by post‐translational modifications (PTMs), such as ubiquitination, but whether it is modified by small ubiquitin‐related modifier (SUMO) remains unknown. The aim of this study was to investigate whether ATF3 is post‐translationally modified by SUMO proteins and also to elucidate SUMOylation of ATF3 on TP53 gene activity. Here we report that ATF3 is clearly defined as a SUMO target protein both in vitro SUMOylation assay using recombinant proteins and at the cellular levels. Furthermore, ATF3 interacted with UBE2I, the only SUMO E2 enzyme found so far. In addition, PIAS3β (a SUMO E3 ligase) enhanced and SENP2 and SENP7 (two SUMOylation proteases) decreased SUMOylation of ATF3, respectively. Finally, we found that ATF3 is selectively SUMOylated at lysine residue 42 but the SUMOylation does not alter subcellular localization of ATF3. We then characterized the functional role of ATF3 SUMOylation on TP53 gene expression. We found that SUMOylation of ATF3 is required for full repression of TP53 gene. Overall, we provide the first evidence that ATF3 is post‐translationally modified by SUMO and SUMOylation of ATF3 plays a functional role in regulation of TP53 gene activity. J. Cell. Biochem. 114: 589–598, 2013. © 2012 Wiley Periodicals, Inc.
Sonographic diagnosis and monitoring of localized langerhans cell histiocytosis of the skull
Authors: Kosiak Wojciech , Piskunowicz Maciej , Swieton Dominik , Bien Ewa , Batko Tomasz 
Published: September 2012

AbstractPurpose.Langerhans cell histiocytosis (LCH) is an infrequent disorder of unknown origin associated with histiocytic proliferation. The bones' involvement (including cranial bones) is the most frequent manifestation of pediatric LCH. Imaging of skull LCH is based predominantly on conventional radiography, CT, scintigraphy, and sometimes MRI. The aim of the study was to investigate the role of sonography (US) in the diagnosis and monitoring of bone lesions in children with localized LCH of the skull.Methods.Twenty‐seven children (15 boys/12 girls, mean age 6.1 years) were diagnosed between 1991 and 2005 in the Department of Pediatrics at the Medical University of Gdansk, Poland. Fourteen children (52%) had localized LCH of the skull.Results.All lesions of the skull visible on CT were visualized on US examination. Overall, 30 focal lesions were revealed by US. The largest bone lesions were accompanied by changes within the adjacent soft tissues. CT revealed 26 lesions, the location and size of which corresponded to the lesions seen on US, but soft‐tissue changes adjacent to the bony lesions were difficult to visualize.Conclusions.The US appearance of focal LCH lesions in cranial bones in children is not pathognomonic, but is characteristic enough to suggest an initial diagnosis and to monitor the evolution of lesions during treatment. US should be considered an additional diagnostic tool for LCH of the skull. Although US of localized LCH cannot replace CT, it could reduce the number of follow‐up CT examinations. © 2012 Wiley Periodicals, Inc. J Clin Ultrasound, 2013
Prognostic value of acute fluid collections diagnosed by ultrasound in the early assessment of severity of acute pancreatitis
Authors: Zerem Enver , Imamović Goran , Latić Ferid , Mavija Zoran 
Published: September 2012

AbstractPurpose:To evaluate the prognostic value of acute fluid collections (AFC) diagnosed by conventional transabdominal ultrasound in the early assessment of severity acute pancreatitis (AP).Methods:We studied 128 consecutive patients with AP between March 2006 and March 2011. The predictor was the number of AFC. Outcome measure was the occurrence of complications. Abdominal sonogram, contrast‐enhanced CT, and pancreatitis‐specific clinical and laboratory findings were performed.Results:AFC were associated with complications (p< 0.0001), Balthazar grade (p = 0.004), Ranson score (p < 0.0001), and the majority of clinical, radiologic, and biochemical parameters for predicting complications of AP (p < 0.05). Univariate logistic regression also revealed significant association between the number of AFC and the occurrence of complications (OR 4.4; 95% CI 2.5–7.6). After the adjustment for covariates, AFC remained prognostic for complications and a cutoff point of >1 AFC was prognostic of their occurrence with 88% sensitivity and 82% specificity.Conclusions:AFC are related to the clinical course of AP and can predict its severity.© 2012 Wiley Periodicals, Inc., J Clin Ultrasound, 2013
Motion artifact reduction of diffusion‐weighted MRI of the liver: Use of velocity‐compensated diffusion gradients combined with tetrahedral gradients
Authors: Ozaki Masanori , Inoue Yusuke , Miyati Tosiaki , Hata Hirohumi , Mizukami Sinya , Komi Shotaro , Matsunaga Keiji , Woodhams Reiko 
Published: September 2012

AbstractPurpose:To assess the effect of motion artifact reduction on the diffusion‐weighted magnetic resonance imaging (DWI‐MRI) of the liver, we compared velocity‐compensated DWI (VC‐DWI) and VC‐DWI combined with tetrahedral gradients (t‐VC‐DWI) to conventional DWI (c‐DWI) in the assessment of apparent diffusion coefficients (ADCs) of the liver.Materials and Methods:In 12 healthy volunteers, the liver was scanned with c‐DWI, VC‐DWI, and t‐VC‐DWI sequences. The signal‐to‐noise ratio (SNR) and ADC of the liver parenchyma were measured and compared among sequences.Results:The image quality was visually better for t‐VC‐DWI than for the others. The SNR for t‐VC‐DWI was significantly higher than that for VC‐DWI (P < 0.05) and comparable to that for c‐DWI. ADCs in both hepatic lobes were significantly lower for t‐VC‐DWI than for c‐DWI (P < 0.01). ADC in the left lobe was significantly lower for VC‐DWI than for c‐DWI (P < 0.01). Although ADC in the left lobe was significantly higher for c‐DWI (P < 0.01), no significant differences in ADCs were found between the right and left lobes for VC‐DWI and t‐VC‐DWI.Conclusion:The use of a t‐VC‐DWI sequence enables us to correct ADCs of the liver for artificial elevation due to cardiac motion, with preserved SNR. J. Magn. Reson. Imaging 2013;37:172–178. © 2012 Wiley Periodicals, Inc.
fMRI of human olfaction at the individual level: Interindividual variability
Authors: Morrot Gil , Bonny Jean‐Marie , Lehallier Benoist , Zanca Michel 
Published: September 2012

AbstractPurpose:To determine whether the range of normal variation of human olfactory functional magnetic resonance imaging (fMRI) activations in healthy single subjects is compatible with the detection of atypical patterns.Materials and Methods:In an event‐related olfactory experiment, the variability of fMRI activation in six bilateral olfactory areas known to be affected in neurodegenerative diseases was measured in a region of interest (ROI) analysis in terms of intensity, localization, and overlap on 51 subjects. fMRI measurements were compared against measurements from a visual experiment performed on 25 subjects.Results:Olfaction induced activations with low intensity, high variability, and a 4‐fold lower contrast‐to‐noise ratio (CNR) than vision. Even in the best case (piriform cortex), mean pairwise activation overlap was still less than 40%. None of the olfactory ROIs showed significant activation for all subjects at the permissive threshold of P < 0.001. A gender‐dependent significantly stronger activation was found in the bilateral piriform cortex of male subjects.Conclusion:Linking t‐statistics and CNR showed that for all olfactory ROIs, CNR is either near or below the estimated threshold of 0.73 found to be necessary to obtain significant activations. In our experimental conditions the low reliability of olfactory activations should prompt major reservations over using fMRI of human olfaction as a diagnostic tool in single subjects. J. Magn. Reson. Imaging 2013;37:92–100. © 2012 Wiley Periodicals, Inc.
Antecedents and outcomes of employee perceptions of intra‐organizational mobility channels
Authors: Webster Jennica R. , Beehr Terry A. 
Published: September 2012

SummaryEmployees' beliefs about how promotions are awarded within their organizations can have important consequences. We conducted two studies that focus on perceptions of the criteria used to make promotion decisions. In Study 1, we identified two types of perceived promotion criteria, performance‐based and nonperformance‐based. Then we use justice and social exchange theories to develop a model linking employee perceptions of promotion criteria to performance via their relationships with promotional justice and organizational commitment. In a sample of 305 employee–supervisor pairs, we found that both promotional justice and organizational commitment mediated between perceptions of promotion criteria and supervisor rated in‐role and extra‐role performance, and that having received a promotion in the past predicted attributions that promotions were based relatively more on performance or nonperformance criteria. Study 2 further examined the role of promotions themselves in the formation of perceptions of promotion criteria. Drawing from image and attribution theories, we hypothesized that the relationship between having received a promotion or not and perceptions of promotion criteria depends on ego defensiveness. In a sample of 145 employees, we found that those who scored high on ego defensiveness and who had not been promoted were especially likely to attribute promotion decisions to nonperformance criteria. Copyright © 2012 John Wiley & Sons, Ltd.
Effects of leadership consideration and structure on employee perceptions of justice and counterproductive work behavior
Authors: Holtz Brian C. , Harold Crystal M. 
Published: September 2012

SummaryIn this paper, we examine the effects of leadership consideration and structure on two important organizational behavior outcomes: employee perceptions of organizational justice and counterproductive work behavior (CWB). We examine these effects across two studies using multisource data (employees and supervisors in Study 1; employees and coworkers in Study 2). Results reveal that consideration and structure have distinct effects across distributive, procedural, informational, and interpersonal dimensions of justice. Moreover, results suggest that consideration and structure have multiplicative effects on employee CWB. We find the highest levels of CWB among employees of supervisors who exhibit high structure and low consideration. Interestingly, results also suggest that the effects of structure on CWB may be curvilinear (u‐shaped) such that moderate levels of structure are associated with the lowest levels of CWB. We discuss implications for future consideration and structure research as well as managerial practice. Copyright © 2012 John Wiley & Sons, Ltd.
Optimizing the fat and water content of impaction bone allograft
Authors: McKenna Paul B. , Leahy J.J. , Masterson Eric L. , McGloughlin Timothy M. 
Published: September 2012

AbstractFresh morselized impacted bone graft usually fails due to shear forces. The presence of fat, water, and marrow particles act as interparticle lubricants, reducing the interlocking of particles and allowing the graft to move more freely. Furthermore, the presence of this incompressible fluid damps and resists compressive forces during impaction, preventing the graft particles from moving into a closer formation. We believe there exists an ideal concentration of fat and water that will maximize resistance to shear forces. We performed mechanical shear testing in vitro on morselized human femoral heads, varying the amount of fat and water to determine their optimum concentrations. Level of fat and water were determined that increased strength by 36% over unaltered bone graft. This is most closely approximated in an operating room by washing and subsequently squeezing the bone graft. Optimizing the fat and water content of bone graft produces a stronger graft that is more resistant to shear stresses, protecting the surgical construct until bone growth can occur. © 2012 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 31: 243–248, 2013
Obligations and Permissions
Authors: Fox Chris 
Published: September 2012

AbstractUtterances and statements that are concerned with obligations and permissions are known as deontic expressions. They can present something of a challenge when it comes to formalising their meaning and behaviour. The content of these expressions can appear to support entailment relations similar to those of classical propositions, but such behaviour can sometimes lead to counter‐intuitive outcomes. Historically, much of the descriptive work in this area has been philosophical in outlook, concentrating on questions of morality and jurisprudence. Some additional contributions have come from computer science, in part due to the need to specify normative behaviour. There are a number of formal proposals that seek to account for obligations and permissions, such as Standard Deontic Logic. In the literature, there has also been discussion of various conundrums and dilemmas that need to be resolved, such as the Good Samaritan, the Knower, the Gentle Murderer, Contrary to Duty Obligations, Ross's Paradox, Jørgensen's Dilemma, Sartre's Dilemma, and Plato's Dilemma. Despite all this work, there still appears to be no definite consensus about how these kinds of expressions should be analysed, or how all the deontic dilemmas should be resolved. It is possible that obligations themselves, as opposed to their satisfaction criteria, do not directly support a conventional logical analysis. It is also possible that a linguistically informed analysis of obligations and permissions may help to resolve some of the deontic dilemmas, and clarify intuitions about how best to formulate a logic of deontic expressions.
Configurational Fluctuation Effects on Counterion Condensation for a Polyelectrolyte Chain
Authors: Miao Bing , Vilgis Thomas A. 
Published: September 2012

AbstractWe investigate the effects of a polyelectrolyte chain's configurational fluctuations on the counterion condensation theoretically. Starting with a straight‐line configuration where the polyelectrolyte chain is totally stretched, the configurational fluctuations are developed by relaxing the stretch. The amount of relaxation appears as a control parameter for configurational fluctuations in this model. The electrostatic potential generated by the fluctuating polyion is obtained through a perturbation calculation around the straight‐line configuration. Adopting the obtained electrostatic potential and using a two‐phase model calculation, the fraction of condensed counterions in the system is calculated. Effects of the Manning parameter and the fluctuations are discussed. In particular, it is shown that configurational fluctuations lead more counterions to be condensed. These observations can be understood in a transparent way in the model. magnified image
Thermal dehydrogenation of amorphous silicon deposited on c‐Si: Effect of the substrate temperature during deposition
Authors: de Calheiros Velozo A. , Lavareda G. , Nunes de Carvalho C. , Amaral A. 
Published: September 2012

AbstractSamples of doped and undoped a‐Si:H were deposited at temperatures ranging from 100 ºC to 350 ºC and then submitted to different dehydrogenation temperatures (from 350 ºC to 550 ºC) and times (from 1 h to 4 h). a‐Si:H films were characterised after deposition through the measurements of specific material parameters such as: the optical gap, the conductivity at 25 ºC, the thermal activation energy of conductivity and its hydrogen content. Hydrogen content was measured after each thermal treatment. Substrate dopant contamination from phosphorus‐doped a‐Si thin films was evaluated by SIMS after complete dehydrogenation and a junction depth of 0.1 mm was obtained. Dehydrogenation results show a strong dependence of the hydrogen content of the as‐deposited film on the deposition temperature. Nevertheless, the dehydrogenation temperature seems to determine the final H content in a way almost independent from the initial content in the sample. H richer films dehydrogenate faster than films with lower hydrogen concentration (© 2012 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Comparison of electrospray ionisation, atmospheric pressure chemical ionisation and atmospheric pressure photoionisation for the identification of metabolites from labile artemisinin‐based anti‐malarial drugs using a QTRAP® mass spectrometer
Authors: Louw Stefan , Njoroge Mathew , Chigorimbo‐Murefu Nyaradzo , Chibale Kelly 
Published: September 2012

RATIONALEArtemisinin‐based drugs and their metabolites are prone to in‐source fragmentation under atmospheric pressure ionisation mass spectrometry (API‐MS) conditions. To facilitate correct and efficient identification of all possible drug metabolites using full scan MS analyzer methods, stable [M + NH4]+ ions should be produced in the MS source.METHODSUsing a high‐performance liquid chromatography (HPLC) hybrid triple quadrupole linear ion trap MS system, electrospray ionisation (ESI), atmospheric pressure chemical ionisation (APCI) and atmospheric pressure photoionisation (APPI) methods were developed for the detection of [M + NH4]+ ions of the test compounds dihydroartemisinin, artemisinin, artemether and artesunic acid. The optimised methods employed ammonium formate buffered HPLC mobile phase in combination with moderate source temperatures (100–200 °C) and showed satisfactorily reduced in‐source fragmentation.RESULTSWith a full scan MS analyser method for the detection of the in vitro metabolites of the test compounds, the respective performance of the ESI and APCI methods was found to be comparable. ESI generally resulted in less in‐source fragmentation. Incorrect assignment of metabolites resulted from strong in‐source fragmentation of artemether using the APPI method. The most number of metabolites could be detected using ESI in combination with a selective MS analyser method.CONCLUSIONSESI and APCI full scan methods proved to be capable of detecting any drug metabolites present in reasonable concentrations, and are useful when employed in addition to selective scan methods that target low level expected metabolites. APPI can be a valuable alternative for detecting expected metabolites due to good signal‐to‐noise (S/N) ratio. Copyright © 2012 John Wiley & Sons, Ltd.
Joint signal‐labeling optimization under peak power constraint
Authors: Kayhan F. , Montorsi G. 
Published: September 2012

SUMMARYIn this paper, we introduce a variation of simulated annealing algorithm for optimizing two‐dimensional constellations with finite number of signals by maximizing the symmetric and pragmatic capacity. Our method also allows the joint optimization of constellation and binary labeling when the objective function is the pragmatic capacity. The algorithm can be applied with constraints on both the peak power and the average and peak power of the constellation. The proposed algorithm does not impose any a priori geometrical structure on the constellation and labeling. Here, we provide results only for the peak power constraints and constellations with up to 32 signals. For the symmetric capacity, optimal constellations depend on the signal to noise ratio and match in several cases the amplitude phase shift keying (APSK). On the other hand, for the pragmatic capacity several novel labeling constellation schemes are introduced, showing interesting differences between the two approaches. For modulation schemes with 32 signals, our optimized constellations perform up to 0.6 dB better than the optimized 4+12+16‐APSK used as the digital video broadcasting (DVB‐S2) standard. Copyright © 2012 John Wiley & Sons, Ltd.