bluuebunny/crossref_metadata_2025_split huggingface dataset:
Genetic evidence for the vital function of osterix in cementogenesis
Authors: Cao Zhengguo , Zhang Hua , Zhou Xin , Han Xianglong , Ren Yinshi , Gao Tian , Xiao Yin , de Crombrugghe Benoit , Somerman Martha J , Feng Jian Q 
Published: January 2012

Abstract
To date, attempts to regenerate a complete tooth, including the critical periodontal tissues associated with the tooth root, have not been successful. Controversy still exists regarding the origin of the cell source for cellular cementum (epithelial or mesenchymal). This disagreement may be partially due to a lack of understanding of the events leading to the initiation and development of the tooth roots and supportive tissues, such as the cementum. Osterix (OSX) is a transcriptional factor essential for osteogenesis, but its role in cementogenesis has not been addressed. In the present study, we first documented a close relationship between the temporal- and spatial-expression pattern of Osx and the formation of cellular cementum. We then generated 3.6-kilobase (kb) collagen type I (3.6-kb Col 1)-Osx transgenic mice, which displayed accelerated cementum formation versus wild-type (WT) controls. Importantly, the conditional deletion of Osx in the mesenchymal cells with two different Cre systems (the 2.3-kb Col 1 and an inducible CAG–Cre estrogen receptor [CreER]) led to a sharp reduction in cellular cementum formation (including the cementum mass and mineral deposition rate) and gene expression of dentin matrix protein 1 (DMP1) by cementocytes. However, the deletion of the Osx gene after cellular cementum formed did not alter the properties of the mature cementum as evaluated by backscattered scanning electron microscopy (SEM) and resin-casted SEM. Transient transfection of Osx in the cementoblasts in vitro significantly inhibited cell proliferation and increased cell differentiation and mineralization. Taken together, these data support: (1) the mesenchymal origin of cellular cementum (from periodontal ligament [PDL] progenitor cells); (2) the vital role of OSX in controlling the formation of cellular cementum; and (3) the limited remodeling of cellular cementum in adult mice. © 2012 American Society for Bone and Mineral Research.
Highlighting and trying to overcome a serious drawback with qspr studies; data collection in different experimental conditions (mixed‐QSPR)
Authors: Beheshti Abolghasem , Riahi Siavash , Ganjali Mohammad Reza , Norouzi Parviz 
Published: January 2012

AbstractThe experimental conditions in quantitative structure–property relationship (QSPR) studies need to be the same for each dataset in case one wishes to relate the property, only to the structure. This major drawback limits QSPR studies due to two reasons: (1) Gathering of physicochemical data obtained under the same experimental condition is difficult. (2) The obtained model is just useful to predict the physicochemical properties under the specific experimental condition. In this article, we report an attempt to highlight the shortcoming of QSPR studies for a property that was measured under different experimental conditions. In addition, we reveal inadequacies that correlating the fluorescence properties and the descriptor of the solvent has. These defects are eventually removed by taking into account the solvent–solute interactions in descriptor calculations. Quantum chemical calculations (HF/6‐31G*) were carried out to optimize geometry and calculate the structural descriptors. The genetic algorithm combined with multiple linear regression method was utilized to construct the linear QSPR models. Because of the better nonlinear relationship between the quantum yield of fluorescence and structural descriptors in comparison with those of a linear relationship, support vector machine was used to construct the nonlinear QSPR model. Result analyses demonstrated that the proposed models meet our goal. © 2012 Wiley Periodicals, Inc. J Comput Chem, 2012
Electronic structure and thermochemical properties of silicon‐doped lithium clusters LinSi0/+, n = 1–8: New insights on their stability
Authors: Tai Truong Ba , Nguyen Minh Tho 
Published: January 2012

AbstractA theoretical investigation on small silicon‐doped lithium clusters LinSi with n = 1–8, in both neutral and cationic states is performed using the high accuracy CCSD(T)/complete basis set (CBS) method. Location of the global minima is carried out using a stochastic search method and the growth pattern of the clusters emerges as follows: (i) the species LinSi with n ≤ 6 are formed by directly binding one Li to a Si of the smaller cluster Lin−1Si, (ii) the structures tend to have an as high as possible symmetry and to maximize the coordination number of silicon. The first three‐dimensional global minimum is found for Li4Si, and (iii) for Li7Si and Li8Si, the global minima are formed by capping Li atoms on triangular faces of Li6Si (Oh). A maximum coordination number of silicon is found to be 6 for the global minima, and structures with higher coordination of silicon exist but are less stable. Heats of formation at 0 K (ΔfH0) and 298 K (ΔfH298), average binding energies (Eb), adiabatic (AIE) and vertical (VIE) ionization energies, dissociation energies (De), and second‐order difference in total energy (Δ2E) of the clusters in both neutral and cationic states are calculated from the CCSD(T)/CBS energies and used to evaluate the relative stability of clusters. The species Li4Si, Li6Si, and Li5Si+ are the more stable systems with large HOMO–LUMO gaps, Eb, and Δ2E. Their enhanced stability can be rationalized using a modified phenomenological shell model, which includes the effects of additional factors such as geometrical symmetry and coordination number of the dopant. The new model is subsequently applied with consistency to other impure clusters LinX with X = B, Al, C, Si, Ge, and Sn. © 2012 Wiley Periodicals, Inc.
Alteration of energy metabolism in Enterobacter aerogenes by external addition of pyrophosphates and overexpression of polyphosphate kinase for enhanced hydrogen production
Authors: Lu Yuan , Lai Qiheng , Zhang Chong , Zhao Hongxin , Xing Xin‐Hui 
Published: January 2012

AbstractBACKGROUND: Bacterial hydrogen evolution releases excess electrons or energy formed during the metabolic oxidations. Until now, few studies have investigated the global regulation of cellular energy flows, pertaining to bacterial hydrogen production for the improvement of hydrogen production. In this study, the cellular energy metabolism of Enterobacter aerogenes was regulated by the addition of pyrophosphate (PPi) and the overexpression of polyphosphate kinase (PPK), to improve hydrogen production.RESULTS: By overexpressing PPK at 10 mmol L−1 PPi, total hydrogen yields were increased by 32.7%. Metabolic flux analysis demonstrated that overexpression of PPK in E. aerogenes resulted in a higher cellular ATP level and a higher NADH consumption rate, which changed the cellular redox state and allowed more electrons to flow into the hydrogen production pathway.CONCLUSION: Alteration of the energy metabolism in E. aerogenes can affect hydrogen production. This implies that if one could accurately control the energy flow or the electron flow in the cells, hydrogen productivity would be further greatly improved. Copyright © 2012 Society of Chemical Industry
Full‐scale biotrickling filtration of volatile organic compounds from air emission in wood‐coating activities
Authors: Lafita Carlos , Penya‐Roja Josep‐Manuel , Gabaldón Carmen , Martínez‐Soria Vicente 
Published: January 2012

AbstractBACKGROUND: Biotrickling filtration could be considered as a suitable and viable technology for controlling the industrial emissions of volatile organic compounds (VOCs) in waste gases. In this study, the performance of a full‐scale biotrickling system, including a passively activated carbon‐smoothing prefilter was investigated for the treatment of exhaust gases from two different paint spray sources at a furniture facility.RESULTS: The VOC profiles were uneven for both sources, but the second source was more irregular, with highly variable VOC loads. The plant was operated at empty bed residence times (EBRTs) between 20 and 100 s. The system was able to control the VOC emissions, so air treated could comply with local legal emission limits under suitable operating conditions (EBRT ∼20 s and EBRT ∼85 s for the first and the second source, respectively). Economic evaluation of the treatment, including investment amortization, showed a total cost per 10,000 m3 of treated air of around 8 € and 35 € for the first and the second sources, respectively.CONCLUSION: The profile, type, and composition of VOC sources were shown to be crucial parameters determining the VOC removal ability and the viability of the biotrickling system. Copyright © 2012 Society of Chemical Industry
Catalytic degradation of aqueous Fischer–Tropsch effluents to fuel gas over oxide‐supported Ru catalysts and hydrothermal stability of catalysts
Authors: Chen Lungang , Zhu Yulei , Zheng Hongyan , Zhang Chenghua , Li Yongwang 
Published: January 2012

AbstractBACKGROUND: The catalytic degradation of aqueous Fischer–Tropsch (FT) effluents to fuel gas over Ru/AC has been investigated. In order to understand the catalytic performance and stability of oxide‐supported Ru catalysts, several oxide supports (titania, zirconia, γ‐alumina and silica) were selected for study, with a focus on the hydrothermal stability of catalysts.RESULTS: The catalytic efficiency for transforming the oxygenates in aqueous FT effluents to C1–C6 alkanes decreased in the order: Ru/ZrO2∼ Ru/TiO2 > Ru/SiO2 > Ru/Al2O3. The conversion of alcohols was greatly suppressed over Ru/γ‐Al2O3. The former two catalysts (Ru/ZrO2 and Ru/TiO2) exhibited enhanced efficiency and long‐term stability (400 h) relative to Ru/SiO2 and Ru/Al2O3. N2‐physisorption, XRD and SEM showed that titania and zirconia exhibited high structural stability in an aqueous environment. However, the structures of γ‐alumina and silica were unstable due to significant drop in surface area and adverse changes in surface morphology. Especially for the case of the Ru/γ‐Al2O3 catalyst, the γ‐alumina was transformed into boehmite structure after reaction, and metal leaching and carbon deposition were extensive.CONCLUSION: Ru/ZrO2 or Ru/TiO2 may be a promising alternative for degrading aqueous FT effluents due to their long‐term stability. Copyright © 2012 Society of Chemical Industry
Time course study on the effects of iodinated contrast medium on intrarenal water transport function using diffusion‐weighted MRI
Authors: Wang Jing , Zhang Yudong , Yang Xuedong , Wang Xiaoying , Zhang Jue , Fang Jing , Jiang Xuexiang 
Published: January 2012

AbstractPurpose:To assess the effects of intravenous‐injected iodinated contrast medium (CM) on intrarenal water diffusion using noninvasive diffusion‐weighted MRI (DW‐MRI).Materials and Methods:Ten New Zealand White rabbits were randomized to receive a 6 mL/kg body weight intravenous injection of clinically used iopamidol‐370 (n = 7) or an equivalent amount of 0.9% physiological saline (n = 3). A sequential DW‐MRI was performed to estimate the intrarenal apparent diffusion coefficient (ADC) at 24 h before and 1 h, 24 h, 48 h, and 72 h after administration.Results:Iopamidol produced a progressive ADC reduction in inner stripes of the renal outer medulla (IS) by 13.92% (P = 0.05) at 1 h, 17.52% (P = 0.02) at 24 h, 20.23% (P = 0.01) at 48 h and 16.31% (P = 0.04) at 72 h after injection. Cortical ADC was decreased by 14.14% (P = 0.01) at 48 h and 14.12% (P = 0.01) at 72 h after injection. Iopamidol produced slight decrease of ADCs in outer stripes of the outer medulla (OS) and inner medulla (IM) of kidney but without statistical difference. In control group, no significant ADC changes was observed in each anatomic compartment due to saline injection (P > 0.05).Conclusion:As demonstrated by DW‐MRI, intravenous iopamidol injection resulted in a successive reduction of intrarenal water diffusion, particularly in IS of kidney. This MR technique may be used as a noninvasive tool to perform a time course study of the pathogenesis associated with contrast‐induced nephropathy (CIN). J. Magn. Reson. Imaging 2012;35:1139‐1144. © 2012 Wiley Periodicals, Inc.
T2‐weighted and diffusion‐weighted MRI for discriminating benign from malignant focal liver lesions: Diagnostic abilities of single versus combined interpretations
Authors: Haradome Hiroki , Grazioli Luigi , Morone Mario , Gambarini Sebastiana , Kwee Thomas C. , Takahara Taro , Colagrande Stefano 
Published: January 2012

AbstractPurpose:To compare the diagnostic accuracies of diffusion‐weighted imaging (DWI), T2‐weighted imaging (T2WI), and the combination of both sequences in discriminating benign from malignant focal liver lesions (FLLs).Materials and Methods:In all, 166 patients with 269 FLLs (153 benign and 116 malignant) were retrospectively evaluated. Two abdominal readers visually assessed the DWI, T2WI, and the combined (DWI+T2WI) image sets in an independent and blinded manner. The diagnostic abilities of each image set in discriminating the benign from the malignant FLLs set were compared using a binary logistic regression model. Pathologic results, consensus reading, and follow‐up imaging were used as the reference standard.Results:The overall characterization accuracy in all lesions of the combined set (80.3%) was significantly higher than those of the T2WI set (68.8%) and DWI set (73.2%) (combined vs. T2WI, P < 0.001; combined vs. DWI, P = 0.001), while there was no significant difference between the T2WI and DWI sets (P = 0.058). All image sets were more accurate in the characterization of malignant FLLs than of benign FLLs (P < 0.001).Conclusion:T2WI and DWI are complementary in discriminating benign from malignant FLLs; their combination improves diagnostic confidence. J. Magn. Reson. Imaging 2012;35:1388–1396. © 2012 Wiley Periodicals Inc.
Ischemic extent as a biomarker for characterizing severity of coronary artery stenosis with blood oxygen‐sensitive MRI
Authors: Tsaftaris Sotirios A. , Tang Richard , Zhou Xiangzhi , Li Debiao , Dharmakumar Rohan 
Published: January 2012

AbstractPurpose:To investigate whether a statistical analysis of myocardial blood‐oxygen‐level‐dependent (mBOLD) signal intensities can lead to the identification and quantification of the ischemic area supplied by the culprit artery.Materials and Methods:Cardiac BOLD images were acquired in a canine model (n = 9) with controllable LCX stenosis at rest and during adenosine infusion on a 1.5T clinical scanner. Statistical distributions of myocardial pixel‐intensities derived from BOLD images were used to compute an area metric (ischemic extent, IE). True myocardial perfusion was estimated from microsphere analysis. IE was compared against a standard metric (segment‐intensity‐response, SIR). Additional animals (n = 3) were used to investigate the feasibility of the approach for identifying ischemic territories due to LAD stenosis from mBOLD images.Results:Regression analyses showed that IE and myocardial flow ratio between rest and adenosine infusion (MFR) were exponentially related (R2 > 0.70, P < 0.001, for end‐systole and end‐diastole), while SIR and MFR were linearly related to end‐systole (R2 = 0.51, P < 0.04) and unrelated to end‐diastole (R2 ≈ 0, P = 0.91). Receiver‐operating‐characteristic analysis that IE was superior to SIR for detecting critical stenosis (MFR ≤2) in end‐systole and end‐diastole. Feasibility studies on LAD narrowing demonstrated that the proposed approach could also identify oxygenation changes in the LAD territories.Conclusion:The proposed evaluation of cardiac BOLD magnetic resonance imaging (MRI) offers marked improvement in sensitivity and specificity for detecting critical coronary stenosis at 1.5T compared to the mean segmental intensity approach. Patient studies are now warranted to determine its clinical utility. J. Magn. Reson. Imaging 2012;35:1338–1348. © 2012 Wiley Periodicals Inc.
Estimation of intersubject variability of cerebral blood flow measurements using MRI and positron emission tomography
Authors: Henriksen Otto M. , Larsson Henrik B.W. , Hansen Adam E. , Grüner Julie M. , Law Ian , Rostrup Egill 
Published: January 2012

AbstractPurpose:To investigate the within and between subject variability of quantitative cerebral blood flow (CBF) measurements in normal subjects using various MRI techniques and positron emission tomography (PET).Materials and Methods:Repeated CBF measurements were performed in 17 healthy, young subjects using three different MRI techniques: arterial spin labeling (ASL), dynamic contrast enhanced T1 weighted perfusion MRI (DCE) and phase contrast mapping (PCM). All MRI measurements were performed within the same session. In 10 of the subjects repeated CBF measurements by 15O labeled water PET had recently been performed. A mixed linear model was used to estimate between subject (CVbetw) and within subject (CVwith) coefficients of variation.Results:Mean global CBF, CVbetw and CVwith using each of the four methods were for PCM 65.2 mL/100 g/min, 17.4% and 7.4%, for ASL 37.1 mL/100 g/min, 16.2% and 4.8%, for DCE 43.0 mL/100 g/min, 20.0%, 15.1% and for PET 41.9 mL/100 g/min, 16.5% and 11.9%, respectively. Only for DCE and PCM a significant positive correlation between measurements was demonstrated.Conclusion:These findings confirm large between subject variability in CBF measurements, but suggest also that in healthy subjects a subject‐method interaction is a possible source of between subject variability and of method differences. J. Magn. Reson. Imaging 2012;35:1290–1299. © 2012 Wiley Periodicals, Inc.
Accuracy of MR elastography and anatomic MR imaging features in the diagnosis of severe hepatic fibrosis and cirrhosis
Authors: Rustogi Rahul , Horowitz Jeanne , Harmath Carla , Wang Yi , Chalian Hamid , Ganger Daniel R. , Chen Zongming E. , Bolster Bradley D. , Shah Saurabh , Miller Frank H. 
Published: January 2012

AbstractPurpose:To compare the diagnostic accuracy of magnetic resonance imaging elastography (MRE) and anatomic MRI features in the diagnosis of severe hepatic fibrosis and cirrhosis.Materials and Methods:Three readers independently assessed presence of morphological changes associated with hepatic fibrosis in 72 patients with liver biopsy including: caudate to right lobe ratios, nodularity, portal venous hypertension (PVH) stigmata, posterior hepatic notch, expanded gallbladder fossa, and right hepatic vein caliber. Three readers measured shear stiffness values using quantitative shear stiffness maps (elastograms). Sensitivity, specificity, and diagnostic accuracy of stiffness values and each morphological feature were calculated. Interreader agreement was summarized using weighted kappa statistics. Intraclass correlation coefficient was used to assess interreader reproducibility of stiffness measurements. Binary logistic regression was used to assess interreader variability for dichotomized stiffness values and each morphological feature.Results:Using 5.9 kPa as a cutoff for differentiating F3‐F4 from F0‐2 stages, overall sensitivity, specificity, and diagnostic accuracy for MRE were 85.4%, 88.4%, and 87%, respectively. Overall interreader agreement for stiffness values was substantial, with an insignificant difference (P = 0.74) in the frequency of differentiating F3‐4 from F0‐2 fibrosis. Only hepatic nodularity and PVH stigmata showed moderately high overall accuracy of 69.4% and 72.2%. Interreader agreement was substantial only for PVH stigmata, moderate for C/R m, deep notch, and expanded gallbladder fossa. Only posterior hepatic notch (P = 0.82) showed no significant difference in reader rating.Conclusion:MRE is a noninvasive, accurate, and reproducible technique compared with conventional features of detecting severe hepatic fibrosis. J. Magn. Reson. Imaging 2012;35:1356–1364. © 2012 Wiley Periodicals, Inc.
Improving quality of arterial spin labeling MR imaging at 3 tesla with a 32‐channel coil and parallel imaging
Authors: Ferré Jean‐Christophe , Petr Jan , Bannier Elise , Barillot Christian , Gauvrit Jean‐Yves 
Published: January 2012

AbstractPurpose:To compare 12‐channel and 32‐channel phased‐array coils and to determine the optimal parallel imaging (PI) technique and factor for brain perfusion imaging using Pulsed Arterial Spin labeling (PASL) at 3 Tesla (T).Materials and Methods:Twenty‐seven healthy volunteers underwent 10 different PASL perfusion PICORE Q2TIPS scans at 3T using 12‐channel and 32‐channel coils without PI and with GRAPPA or mSENSE using factor 2. PI with factor 3 and 4 were used only with the 32‐channel coil. Visual quality was assessed using four parameters. Quantitative analyses were performed using temporal noise, contrast‐to‐noise and signal‐to‐noise ratios (CNR, SNR).Results:Compared with 12‐channel acquisition, the scores for 32‐channel acquisition were significantly higher for overall visual quality, lower for noise and higher for SNR and CNR. With the 32‐channel coil, artifact compromise achieved the best score with PI factor 2. Noise increased, SNR and CNR decreased with PI factor. However mSENSE 2 scores were not always significantly different from acquisition without PI.Conclusion:For PASL at 3T, the 32‐channel coil at 3T provided better quality than the 12‐channel coil. With the 32‐channel coil, mSENSE 2 seemed to offer the best compromise for decreasing artifacts without significantly reducing SNR, CNR. J. Magn. Reson. Imaging 2012;35:1233‐1239. © 2012 Wiley Periodicals, Inc.
Rubella immune status among immigrant and nonimmigrant women in Spain
Authors: Ramos J.M. , Milla A. , Rodríguez J.C. , Gutiérrez F. 
Published: January 2012

AbstractA cross‐sectional study of seroprevalence of rubella antibodies was carried out in all immigrant pregnant women (1,627) from February 2006 to June 2010. For each immigrant woman one Spanish pregnant woman was recruited. The seroprevalence of IgG antibodies against rubella in immigrant women was 92% (95% confidence interval [CI]: 90.4–93.3), and in native women was 97.7% (95%CI: 96.7–98.4) (P < 0.001). Immunity against was lowest among women from Latin America (odds ratio [OR]: 0.17), followed by women from Asia (OR: 0.20), Sub‐Saharan Africa (OR: 0.27) and Northern Africa (OR: 0.37). Female immigrants from developing countries should be targeted for immunization to reduce the risk of congenital rubella. J. Med. Virol. 84:548–550, 2012. © 2011 Wiley Periodicals, Inc.