bluuebunny/crossref_metadata_2025_split huggingface dataset:
Mislocalization of CDK11/PITSLRE, a regulator of the G2/M phase of the cell cycle, in Alzheimer disease
Authors: Bajić Vladan , Su Bo , Lee Hyoung-Gon , Kudo Wataru , Siedlak Sandra , Živković Lada , Spremo-Potparević Biljana , Djelic Ninoslav , Milicevic Zorana , Singh Avneet , Fahmy Lara , Wang Xinglong , Smith Mark , Zhu Xiongwei 
Published: April 2011

AbstractPost-mitotic neurons are typically terminally differentiated and in a quiescent status. However, in Alzheimer disease (AD), many neurons display ectopic re-expression of cell cycle-related proteins. Cyclin-dependent kinase 11 (CDK11) mRNA produces a 110-kDa protein (CDK11p110) throughout the cell cycle, a 58-kDa protein (CDK11p58) that is specifically translated from an internal ribosome entry site and expressed only in the G2/M phase of the cell cycle, and a 46-kDa protein (CDK11p46) that is considered to be apoptosis specific. CDK11 is required for sister chromatid cohesion and the completion of mitosis. In this study, we found that the expression patterns of CDK11 vary such that cytoplasmic CDK11 is increased in AD cellular processes, compared to a pronounced nuclear expression pattern in most controls. We also investigated the effect of amyloid precursor protein (APP) on CDK11 expression in vitro by using M17 cells overexpressing wild-type APP and APP Swedish mutant phenotype and found increased CDK11 expression compared to empty vector. In addition, amyloid-β25–35 resulted in increased CDK11 in M17 cells. These data suggest that CDK11 may play a vital role in cell cycle re-entry in AD neurons in an APP-dependent manner, thus presenting an intriguing novel function of the APP signaling pathway in AD.
Stress-induced expression of p53 target genes is insensitive to SNW1/SKIP downregulation
Authors: Tolde Ondřej , Folk Petr 
Published: April 2011

AbstractPharmacological inhibition of protein kinases that are responsible for the phosphorylation of the carboxy-terminal domain (CTD) of RNA Pol II during transcription by 5,6-dichloro-1-beta-D-ribofuranosyl-benzimidazole (DRB) leads to severe inhibition of mRNA synthesis and activates p53. Transcription of the p53 effectors that are induced under these conditions, such as p21 or PUMA, must bypass the requirement for CTD phosphorylation by the positive elongation factor P-TEFb. Here, we have downregulated SNW1/SKIP, a splicing factor and a transcriptional co-regulator, which was found to interact with P-TEFb and synergistically affect Tat-dependent transcription elongation of HIV 1. Using the colon cancer derived cell line HCT116, we have found that both doxorubicin- and DRB-induced expression of p21 or PUMA is insensitive to SNW1 downregulation by siRNA. This suggests that transcription of stress response genes, unlike, e.g., the SNW1-sensitive mitosis-specific genes, can proceed uncoupled from regulators that normally function under physiological conditions.
Stereoselective synthesis of the polar part of mycestericins E and G
Authors: Martinková Miroslava , Gonda Jozef , Uhríková Alena , Kováčvá Margaréta 
Published: April 2011

Abstract5-O-(t-Butyldimethylsilyl)-3-deoxy-3-C-hydroxymethyl-1,2-O-isopropylidene-3-(methoxycarbonylamino)-α-d-xylofuranose IV has been proved to be an appropriate building block in the stereoselective synthesis of methyl (4S)-4-[(1′R)-1′-acetoxy-4′-oxobutyl]-3-benzyl-2-oxooxazolidine-4-carboxylate III representing the polar part of the naturally occurring mycestericins E and mycestericins G.
Synthesis and crystal and molecular structures of N,N′-methylenedipyridinium tetrachlorozincate(II) and N,N′-methylenedipyridinium tetrachlorocadmate(II)
Authors: Al-Ktaifani Mahmoud , Rukiah Mwaffak 
Published: April 2011

AbstractTreatment of N,N′-methylenedipyridinium dichloride [C5H5N-CH2-NC5H5]Cl2 with MCl2 (M = Zn or Cd) in aqueous solution gives the organic-inorganic hybrid ionic compounds [C5H5N-CH2-NC5H5] · [MCl4]. Both complex salts were fully characterised by multinuclear NMR spectroscopy, elemental analysis, and their molecular structures confirmed by powder X-ray diffraction studies. The most striking feature in both solid state structures was the presence of the C…Cl-M short contacts between the organic [C5H5N-CH2-NC5H5] dication and inorganic [MCl4] anion, which led to different crystal packing. For [C5H5N-CH2-NC5H5]·[ZnCl4], the C…Cl-Zn interactions led to the alternating arrangement of [C5H5N-CH2-NC5H5]2+[ZnCl4]2− to form 1-D chains in the direction [010], and each individual chain had a two-fold rotational axis along the b axis, while for [C5H5N-CH2-NC5H5] · [CdCl4] the C…Cl-Cd associations gave 2-D network. In both solid state structures, the presence of Cl-ring centroid distances gave a strong indication of some form of Cl-π interactions.
Properties of poly(γ-benzyl l-glutamate) membrane modified by polyurethane containing carboxyl group
Authors: Zhu Guo-Quan , Wang Fa-Gang , Gao Qiao-Chun , Li Guo-Chang , Wang Ping 
Published: April 2011

AbstractA series of poly(γ-benzyl l-glutamate) (PBLG)/polyurethane (PU) containing carboxyl group blend membranes was prepared by casting the polymer blend solution in dimethylformamide (DMF). The surface morphology of the PBLG/PU blend membranes was investigated by atomic force microscopy (AFM) and scanning electron microscopy (SEM). Thermal, mechanical, and chemical properties of PBLG/PU blend membranes were studied by differential scanning calorimetry (DSC), tensile tests and other physical methods. It was revealed that the introduction of PU could exert outstanding effects on the morphology and the properties of PBLG membrane.
Hydrogel for Cell Housing in the Brain and in the Spinal Cord
Authors: Perale Giuseppe , Giordano Carmen , Bianco Fabio , Rossi Filippo , Tunesi Marta , Daniele Francesco , Crivelli Filippo , Matteoli Michela , Masi Maurizio 
Published: April 2011

Purpose Neurons in the adult mammalian central nervous system do not proliferate or renew themselves and consequently strong interest in cell replacement therapies to repair brain and spinal cord damages has emerged in the last decade. Methods An injectable resorbable hydrogel with a controlled nanostructure, specifically designed for neural cell housing, was developed together with a new protocol for building three-dimensional (3D) biohybrid cell/hydrogel constructs: cells are housed within the polymeric matrix which is directly built with a specific cell culture media. This matrix was tested with standard glial populations, primary astrocytes and mesenchymal stem cells. Results Physico-chemical characterization of the hydrogel matrix confirmed a 2- week (+ 2 days) stability before massive degradation; mean mesh size of about 5 nm and thixotropic behavior with transition yield stress at 60+5 Pa. Cell survival within the hydrogel resulted in about 55±5% (minimum value) survivals, data also confirmed by optical assessments. Cell viability also remained high after extraction from the gel, indicating survival to inclusion latency period. Conclusions Since the intimate structure of the gel mimics extracellular matrix cells as would be expected to be found in an in vivo context, this polymeric formulation is a promising base for building 3D constructs for neural cell housing, in which cells are embedded and kept alive directly from the time of polycondensation.
Method for Autologous Single Skin Cell Isolation for Regenerative Cell Spray Transplantation with Non-Cultured Cells
Authors: Gerlach Jörg C. , Johnen Christa , Ottoman Christian , Bräutigam Kirsten , Plettig Jörn , Belfekroun Claudia , Münch Sandra , Hartmann Bernd 
Published: April 2011

Background There is a therapeutic gap for patients with deep partial-thickness wounds (Grade IIb) of moderate size that were initially not treated with split- or mesh grafting to avoid overgrafting, but developed delayed wound healing around two weeks after injury - at which time grafting is typically not indicated anymore. Delayed wound healing is often associated with esthetically unsatisfactory results and sometimes functional problems. An innovative cell isolation method for cell spray transplantation at the point of care, which eliminates cell culture prior to treatment, was implemented for this population of burn patients in our center. Methods Autologous skin cell spray transplantation was initiated by taking healthy skin. The dermal/epidermal layers were separated using enzymatic digestion with 40 min dispase application, followed by 15 min trypsin application for basal kerationcyte isolation, 7 min cell washing by centrifugation, followed by transferring the cells for spraying into Ringer lactate solution. The procedure was performed on site in a single session immediately following the biopsy. After sharp wound debridement, cells were immediately transplanted by deposition with a cell sprayer for even distribution of the cell suspension. Results and Conclusions Eight patients were treated (mean age 30.3 years, mean burn total body surface area 14%, mean Abbreviated Burn Severity Index (5 points). The mean time to complete re-epithelialization was 12.6 days. All patients exhibited wound healing with improved esthetic and functional quality. Our initial experience for the use of non-cultured cells using a two-enzyme approach with cell washing suggests shortened time for wound closure, suggesting that the method may potentially avoid longer-term complications.
Brief communication: Correcting overestimation when determining two‐dimensional occlusal area in human molars
Authors: Schmidt Christopher , Ousley Stephen , Schmidt Molly 
Published: April 2011

AbstractThe robustness index (RI) is determined by multiplying dental mesiodistal and buccolingual diameters, and is used to estimate occlusal area. However, because teeth are not rectangular its calculation consistently causes overestimations. Moreover, teeth, in particular molars, are not identically shaped so overestimations vary. The current study seeks to determine the extent to which overestimations are affected by tooth shape and to improve RI's efficacy. Initially, 120 molars were sorted into six shape groups, which were determined by hypocone/hypoconulid expression. Three maxillary and three mandibular shape groups were set using the Arizona State University Dental Anthropology System. ANOVA results determined that RI overestimations, which averaged around 20%, were not the same for each shape category. Maxillary molars with large hypocones and mandibular molars with no hypoconulids were overestimated significantly less than the other molar groups. Regression‐based correction formulae were generated and applied to the original sample. These formulae far more precisely estimated tooth area than RI and there were no differences in estimation based upon tooth shape. A subsequent validation study of 24 additional molars was undertaken to test the formulae on teeth not from the original sample. Overestimation/underestimation averaged 0.5% and was about the same for each of the tooth shape groups. Finally, six new correction formulae were generated using all 144 molars. The correction formulae provide, what is termed here, an adjusted robustness index (ARI), and it is recommended that ARI is used in future studies of molar occlusal area. Am J Phys Anthropol, 2011. © 2011 Wiley‐Liss, Inc.
Degradation of thiram in water, soil and plants: a study by high‐performance liquid chromatography
Authors: Gupta Bina , Rani Manviri , Kumar Rahul 
Published: April 2011

ABSTRACTA comprehensive study was conducted to evaluate the persistence of thiram in water and soil under controlled conditions and on two plants, namely tomato and radish, in field conditions. In order to follow the decay of the pesticide, an HPLC procedure was developed employing an octadecyl endcapped RP‐C18 column using a mixture of acetonitrile and water as the mobile phase and an ultraviolet detector. Studies conducted in water at different temperature, pH and organic content revealed that the persistence of the pesticide decreases with the increase in all the three variables. In the three different types of soils studied, the effect of pH was more or less apparent on a similar line. On average a slower decay was observed in the case of plants than in water and soil. Copyright © 2011 John Wiley & Sons, Ltd.
Toward the Assignment of the Manganese Oxidation Pattern in the Water‐Oxidizing Complex of Photosystem II: A Time‐Dependent DFT Study of XANES Energies
Authors: Jaszewski Adrian R. , Petrie Simon , Pace Ronald J. , Stranger Rob 
Published: April 2011

AbstractDensity functional theory (DFT) and time‐dependent DFT (TDDFT) calculations are reported on three sets of isomeric models of the {Mn4/Ca} water‐oxidizing complex of photosystem II (PS II), which share the general formula [CaMn4O4(N2C3H4)(RCOO)6]q⋅(H2O)n (R=H, CH3; q=−1, 0, +1, +2; n=3, 4, 5, 6, 7). Comparison with the full range of available data on Mn K‐edge X‐ray absorption energy values determined for the photosystem allows us to validate the structures that correspond to the particular S states and to determine their Mn oxidation patterns. By using a new TDDFT procedure, it is shown that variations in the absolute K‐edge energy values for a particular S state, reported by different research groups, can be quantitatively explained by different geometries adopted by the Mn cluster, which demonstrates flexibility in the position of the fourth ‘dangling’ Mn atom in relation to a cubane structure created by the Ca atom and the three other Mn atoms. Computational results show that each step of the S cycle occurs by removal of one electron directly from the Mn cluster. This Mn‐centered oxidation still agrees with the small difference observed experimentally between the K‐edge energy values of the S2 and S3 states of the photosystem, thus resolving a controversy as to whether this represents ligand‐centered or metal‐centered oxidation. The overall oxidation state of Mn atoms in the tetramanganese cluster during functional turnover changes from 2.75 for S0, 3.00 for S1, and 3.25 for S2 up to 3.50 for the S3 state, which is systematically 0.50 lower than the previously proposed oxidation states of the cluster. The calculations give insight into why these earlier, purely empirical, assignments of the Mn oxidation levels in PS II could be in error.
Semiclathrates of the Ge–P–Te System: Synthesis and Crystal Structures
Authors: Kirsanova Maria A. , Reshetova Liudmila N. , Olenev Andrei V. , Abakumov Artem M. , Shevelkov Andrei V. 
Published: April 2011

AbstractNovel compounds [Ge46−xPx]Tey (13.9≤x≤15.6, 5.92≤y≤7.75) with clathrate‐like structures have been prepared and structurally characterized. They crystallize in the space group Fm$\bar 3$ with the unit cell parameter changing from 20.544(2) to 20.698(2) Å (Z=8) on going from x=13.9 to x=15.6. Their crystal structure is composed of a covalently bonded GeP framework that hosts tellurium atoms in the guest positions and can be viewed as a peculiar variant of the type I clathrate superstructure. In contrast to the conventional type I clathrates, [Ge46−xPx]Tey contain tricoordinated (3b) atoms and no vacancies in the framework positions. As a consequence of the transformation of the framework, the majority of the guest tellurium atoms form a single covalent bond with the host framework and thus the title compounds are the first representative of semiclathrates with covalent bonding. A comparison is made with silicon clathrates and the evolution of the crystal structure upon changing the tellurium content is discussed.
UARA in edge routers: an effective approach to user fairness and traffic shaping
Authors: Khosroshahy Masood 
Published: April 2011

SUMMARYThe ever‐increasing share of the peer‐to‐peer (P2P) traffic flowing in the Internet has unleashed new challenges to the quality of service provisioning. Striving to accommodate the rise of P2P traffic or to curb its growth has led to many schemes being proposed: P2P caches, P2P filters, ALTO mechanisms and re‐ECN. In this paper, we propose a scheme named ‘UARA:textbfUser/Application‐aware RED‐based AQM’ which has a better perspective on the problem: UARA is proposed to be implemented at the edge routers providing real‐time near‐end‐user traffic shaping and congestion avoidance. UARA closes the loopholes exploited by the P2P traffic by bringing under control the P2P users who open and use numerous simultaneous connections. In congestion times, UARA monitors the flows of each user and caps the bandwidth used by ‘power users’ which leads to the fair usage of network resources. While doing so, UARA also prioritizes the real‐time traffic of each user, further enhancing the average user quality of experience (QoE). UARA hence centralizes three important functionalities at the edge routers: (1) congestion avoidance; (2) providing user fairness; (3) prioritizing real‐time traffic. The simulation results indicate that average user QoE is significantly improved in congestion times with UARA at the edge routers. Copyright © 2011 John Wiley & Sons, Ltd.
Synthesis, Crystal Structures and Magnetic Properties of a Phenoxo‐Bridged Dinuclear CuII Complex and a Dicyanamide Bridged Novel Molecular Rectangle Based on It
Authors: Biswas Apurba , Drew Michael G. B. , Ribas Joan , Diaz Carmen , Ghosh Ashutosh 
Published: April 2011

AbstractThe phenoxo‐bridged dinuclear CuII complex [Cu2L2(NCNCN)2] (1) and the dicyanamide‐bridged molecular rectangle [Cu4L4{μ1,5‐(NCNCN)2}]·(ClO4)2(H2O)2 (2) were synthesized using the tridentate reduced Schiff‐base ligand HL {2‐[(2‐dimethylamino‐ethylamino)methyl]phenol}. The complexes were characterized by X‐ray structural analyses and variable‐temperature magnetic susceptibility measurements. Complex 2 was formed through the joining of the phenoxo‐bridged dinuclear Cu2O2 cores of 1 via the μ1,5‐bridging mode of dicyanamide. The structural properties of the Cu2O2 cores in two complexes are significantly different. The geometry of the copper ions is distorted trigonal bipyramid in 1 but is nearly square‐pyramidal in 2. These differences have a marked effect on the magnetic properties of two compounds. Although both are antiferromagnetically coupled, the coupling constants (J = –185.2 and –500.9 cm–1 for 1 and 2, respectively) differ considerably.
Three New Antimicrobial Metabolites from the Endophytic Fungus Phomopsis sp.
Authors: Ahmed Ishtiaq , Hussain Hidayat , Schulz Barbara , Draeger Siegfried , Padula Daniele , Pescitelli Gennaro , van Ree Teunis , Krohn Karsten 
Published: April 2011

AbstractTwo new chromones, phomochromone A and B (1 and 2), and one new natural cyclopentenone derivative, phomotenone (3), together with six known compounds, phomosines A–D (4–7), (1S,2S,4S)‐trihydroxy‐p‐menthane (8), and 5‐methylmellein (9), have been isolated from the endophytic fungus Phomopsis sp. through a bioassay‐guided procedure. The structures of the new compounds were assigned on the basis of the 1H and 13C NMR spectra, DEPT, and 2D COSY, HMQC, HMBC, and NOESY experiments, supported by molecular modelling. The absolute configurations of compounds 1–3 were assigned by TD‐DFT CD calculations and, surprisingly, the two related phomochromones A and B have an opposite configuration at C‐2. Compounds 1–3 show good antifungal (Microbotryum violaceum), antibacterial (Escherichia coli, Bacillus megaterium), and antialgal (Chlorella fusca) activities. Compound 8 shows good antialgal and antibacterial activity.
Pilot study of absorption of NO2 with Na2S aqueous solutions
Authors: Chen Luke , Lin Kun‐Fon , Yang Chen‐Lu 
Published: April 2011

AbstractA pilot‐scale study of sodium sulfide (Na2S) aqueous solutions for NO2 absorption was conducted to obtain field data for process design and system operations. Considered parameters include Na2S concentrations in the scrubbing solutions, gas mass flow rate, liquid mass flow rate, liquid/gas ratio (L/G), pH, and gas residence time. The effects of these parameters on NO2 absorption in a packed tower were investigated thoroughly. The height of transfer unit of the system was deducted as a function of the tested parameters that can be used for designing a NOx scrubbing system. The absorption of NO2 is not sensitive to the inlet NO2 concentration. However, as expected, the NO2 absorption increases with the increase of L/G ratio. An L/G greater than 2.5 is essential to a practical NO2 scrubbing application. The pilot test suggested that the scrubbing solution is with Na2S concentration greater than 0.0015 M at pH 9. The solution effectively removed more than 90% of the incoming NO2 in the five‐foot height packed bed scrubber. The study also indicates that a gas residence time of 4.5 s is essential to achieve more than 80% NO2 absorption. © 2011 American Institute of Chemical Engineers Environ Prog, 2011.
Katian prelude to the Hirnantian (Late Ordovician) mass extinction: a Baltic perspective
Authors: Kaljo Dimitri , Hints Linda , Hints Olle , Männik Peep , Martma Tõnu , Nõlvak Jaak 
Published: April 2011

AbstractThe diversity of several groups of Late Ordovician fossils in the Baltic is discussed and corresponding curves are presented. The curves are correlated with the latest δ13C trend and probable sea surface temperatures of the equatorial ocean in order to link biodiversity and environmental changes. Most groups of macrofossils and acritarchs showed a high‐level biodiversity in the Sandbian and early Katian during a sea level high stand and optimal temperatures. Conodont diversity peaked in the mid‐Katian, scolecodonts in the late Katian and rugose corals even in the Hirnantian, indicating their different ecological demands and the evolutionary status of each group. The diversity peak close to the Guttenberg δ13C excursion marks a turning point in environmental evolution when a new global cooling began but tropical conditions persisted in Baltica due to its northward drift. Biodiversity fluctuated during the Katian. Two diversity peaks noted in the Katian are followed by low‐diversity episodes showing a general step by step decrease in diversity, and a correlation with variable sea level and episodes of climatic cooling. It suggests that the Hirnantian mass extinction was preceded by a rather prolonged period of biodiversity change here called the Katian prelude. Katian biodiversity curves and their links with different facies parameters show that environmental conditions within the ecosystem were the main drivers of change, not solely temperature or more generally climate, but also sedimentary environments including water dynamics together with depth and substrate conditions. The biotic component is less well known, but also important. Copyright © 2011 John Wiley & Sons, Ltd.