bluuebunny/crossref_metadata_2025_split huggingface dataset:
Methyltrioxorhenium Catalysis in Nonconventional Solvents: A Great Catalyst in a Safe Reaction Medium
Authors: Crucianelli Marcello , Saladino Raffaele , De Angelis Francesco 
Published: April 2010

AbstractThe requirement that chemical processes are sustainabable, reflected in waste reduction and the use of safe reagents and reaction conditions, is becoming even more stringent as a result of pressure by society and governments to preserve the environment and protect human health. Catalysis offers numerous benefits related to green chemistry, including lowered energetic reaction requirements; catalytic, rather than stoichiometric, amounts of materials; increased selectivity; lowered consumption of processing and separation agents; and, in many cases, the use of less‐toxic compounds. Our research group has for a long time been studying methyltrioxorhenium in the oxyfunctionalization of different substrates, by using H2O2 or its urea‐hydrogen peroxide complex as the primary oxidant. In this Review paper we aim to provide a full literature account on the catalytic activity and selectivity of methyltrioxorhenium in the oxyfunctionalization reaction, either in nonconventional solvents or under solvent‐free conditions, with a particular emphasis on the use of ionic liquids as green reaction media.
The checkpoint kinase ATM protects against stress‐induced elevation of cyclin D1 and potential cell death in neurons
Authors: Hitomi Masahiro , Stacey Dennis W. 
Published: April 2010

AbstractQuantitative cytometric studies show that cyclin D1 levels must decline during S phase for proper cell cycle progression, and that cyclin D1 decline follows phosphorylation induced by the checkpoint kinases ataxia telangiectasia mutated (ATM) and ATM and Rad3‐related (ATR). ATM is mutated in ataxia telangiectasia (AT), a disease characterized by progressive neurodegeneration. Importantly, neurodegeneration in many cases has been linked to the increased expression of cyclin D1 in neurons leading to inappropriate cell cycle entry. These facts prompted us to test the possibility that ATM normally protects against neural degeneration by suppressing cyclin D1 levels, particularly following genotoxic stress. For this purpose, neural stem cells were induced to differentiate into mature neural cells, including neurons. ATM activity in these cultures was inhibited with a specific chemical inhibitor in the presence or absence of hydrogen peroxide treatment, and the effect on cyclin D1 expression was determined by quantitative, single cell cytometric analyses. As predicted, inhibition of ATM did promote elevation of cyclin D1 in differentiated neurons, particularly under conditions of oxidative stress. The survival of differentiated neurons and of neural stem cells was reduced by such treatments. These data support our suggestion that ATM functions to maintain low levels of cyclin D1 expression in differentiated neurons; and may provide important clues in understanding neural degeneration in general. © 2010 International Society for Advancement of Cytometry
Temporal and spatial expression of CCN genes in zebrafish
Authors: Fernando Carol A. , Conrad Patricia A. , Bartels Cynthia F. , Marques Tomas , To Michael , Balow Stephanie A. , Nakamura Yukio , Warman Matthew L. 
Published: April 2010

AbstractThe six mammalian CCN genes (Cyr61, CTGF, Nov, WISP1, WISP2, WISP3) encode a family of secreted, cysteine‐rich, multimodular proteins having roles in cell proliferation, adhesion, migration, and differentiation during embryogenesis, wound healing, and angiogenesis. We used bioinformatics to identify 9 CCN genes in zebrafish (zCCNs), 6 of which have not been previously described. When compared with mammalian CCN family members, 3 were paralogs of Cyr61, 2 of CTGF, 2 of WISP1, 1 of WISP2, and 1 of WISP3. No paralog of Nov was found. In situ hybridization was performed to characterize the sites of expression of the zCCNs during early zebrafish development. zCCNs demonstrated both unique and overlapping patterns of expression, suggesting potential division of labor between orthologous genes and providing an alternate approach to gene function studies that will complement studies in mammalian models. Developmental Dynamics 239:1755–1767, 2010. © 2010 Wiley‐Liss, Inc.
Staying alive: Dalmatian mediated blocking of apoptosis is essential for tissue maintenance
Authors: Kerman Bilal E. , Andrew Deborah J. 
Published: April 2010

AbstractIn an EMS screen for mutations disrupting tracheal development, we identified new alleles of the dalmation (dmt) gene, which had previously been shown to affect peripheral nervous system (PNS) development. Here, we demonstrate that dmt loss results in programmed cell death, disrupting PNS patterning and leading to large gaps in the salivary duct and trachea. Dmt loss results in increased expression of the proapoptotic regulator genes head involution defective (hid) and reaper (rpr), and deletion of these genes or tissue‐specific expression of the baculoviral apoptotic inhibitor P35 rescues the dmt defects. dmt is also required to protect cells from irradiation induced expression of hid and rpr during the irradiation resistant stage, which begins as cells become irreversibly committed to their final fates. Thus, we propose that Dmt keeps cells alive by blocking activation of hid and rpr as cells become irreversibly committed. Developmental Dynamics 239:1609–1621, 2010. © 2010 Wiley‐Liss, Inc.
Prickle1b mediates interpretation of migratory cues during zebrafish facial branchiomotor neuron migration
Authors: Mapp Oni M. , Wanner Sarah J. , Rohrschneider Monica R. , Prince Victoria E. 
Published: April 2010

AbstractThe facial branchiomotor neurons undergo a characteristic tangential migration in the vertebrate hindbrain. Several signaling mechanisms have been implicated in this process, including the non‐canonical Wnt/planar cell polarity (PCP) pathway. However, the role of this signaling pathway in controlling the dynamics of these neurons is unclear. Here, we describe the cellular dynamics of the facial neurons as they migrate, focusing on the speed and direction of migration, extension of protrusions, cell shape, and orientation. Furthermore, we show that the PET/LIM domain protein Prickle1b (Pk1b) is required for several aspects of these migratory behaviors, including cell orientation. However, we find that centrosome localization is not significantly affected by disruption of Pk1b function, suggesting that polarization of the neurons is not completely lost. Together, our data suggest that Pk1b function may be required to integrate the multiple migratory cues received by the neurons into polarization instructions for proper posterior movement. Developmental Dynamics 239:1596–1608, 2010. © 2010 Wiley‐Liss, Inc.
Embryonic and not maternal trisomy causes developmental attenuation in the Ts65Dn mouse model for Down syndrome
Authors: Blazek Joshua D. , Billingsley Cherie N. , Newbauer Abby , Roper Randall J. 
Published: April 2010

AbstractTrisomy 21 results in Down syndrome (DS) and causes phenotypes that may result from alterations of developmental processes. The Ts65Dn mouse is the most widely used genetic and phenotypic model for DS. We used over 1,500 offspring from Ts65Dn and two nontrisomic genetically similar control strains to investigate the influence of trisomy on developmental alterations and number of offspring. For the first time, we demonstrate gross developmental attenuation of Ts65Dn trisomic offspring at embryonic day (E) 9.5 and E13.5 and show that the major determinant of the developmental changes is segmental trisomy of the embryo and not the trisomic maternal uterine environment. Maternal alleles of nontrisomic genes linked to Pde6b may also influence the development of Ts65Dn offspring. Both developmental attenuation and the contribution of trisomic and nontrisomic genes are important components in the genesis of DS phenotypes. Developmental Dynamics 239:1645–1653, 2010. © 2010 Wiley‐Liss, Inc.
Natural killer cells become tolerogenic after interaction with apoptotic cells
Authors: Chong Wai Po , Zhou Jianfang , Law Helen K. W. , Tu Wenwei , Lau Yu Lung 
Published: April 2010

AbstractNK cells are effectors in innate immunity and also participate in immunoregulation through the release of TGF‐β1 and lysis of activated/autoreactive T cells. Apoptotic cells (AC) have been shown to induce tolerogenic properties in innate immune cells, including macrophages and dendritic cells, but not NK cells. In this study, we demonstrated that after interaction with AC, NK cells released TGF‐β1, which in turn suppressed the production of IFN‐γ by NK cells upon IL‐12 and IgG activation. We further identified phosphatidylserine as a potential target on AC for the NK cells, as phosphatidylserine could stimulate NK cells to release TGF‐β1, which in turn suppressed CD4+ T‐cell proliferation and activation. Moreover, AC‐treated NK cells displayed cytotoxicity against autologous‐activated CD4+ T cells by upregulating NKp46. This lysis occurred in part through the NKp46‐vimentin pathway, as activated CD4+ T cells expressed vimentin on the cell surface and blocking of vimentin or NKp46, but not other NK‐cell receptors, significantly suppressed the NK‐cell cytotoxicity. We report here a novel interaction between NK cells and AC, resulting in the tolerogenic properties of NK cells required for immune contraction.
Differential subcellular localization of the regulatory T‐cell protein LAG‐3 and the coreceptor CD4
Authors: Woo Seng‐Ryong , Li Nianyu , Bruno Tullia C. , Forbes Karen , Brown Scott , Workman Creg , Drake Charles G. , Vignali Dario A. A. 
Published: April 2010

AbstractCD4 binds to MHC class II molecules and enhances T‐cell activation. The CD4‐related transmembrane protein LAG‐3 (lymphocyte activation gene‐3, CD223) binds to the same ligand but inhibits T‐cell proliferation. We have previously shown that LAG‐3 cell surface expression is tightly regulated by extracellular cleavage in order to regulate its potent inhibitory activity. Given this observation and the contrasting functions of CD4 and LAG‐3, we investigated the cell distribution, location and transport of these related cell surface molecules. As expected, the vast majority of CD4 is expressed at the cell surface with minimal intracellular localization, as determined by flow cytometry, immunoblotting and confocal microscopy. In contrast, nearly half the cellular content of LAG‐3 is retained in intracellular compartments. This significant intracellular storage of LAG‐3 appears to facilitate its rapid translocation to the cell surface following T‐cell activation, which was much faster for LAG‐3 than CD4. Increased vesicular pH inhibited translocation of both CD4 and LAG‐3 to the plasma membrane. While some colocalization of the microtubule organizing center, early/recycling endosomes and secretory lysosomes was observed with CD4, significantly greater colocalization was observed with LAG‐3. Analysis of CD4:LAG‐3 chimeras suggested that multiple domains may contribute to intracellular retention of LAG‐3. Thus, in contrast with CD4, the substantial intracellular storage of LAG‐3 and its close association with the microtubule organizing center and recycling endosomes may facilitate its rapid translocation to the cell surface during T‐cell activation and help to mitigate T‐cell activation.
New Mixed‐Valence MnII/III6 Complexes Bearing Oximato and Azido Ligands: Synthesis, and Structural and Magnetic Characterization
Authors: Lampropoulos Christos , Stamatatos Theocharis C. , Manos Manolis J. , Tasiopoulos Anastasios J. , Abboud Khalil A. , Christou George 
Published: April 2010

AbstractThe combined use of the anion of methyl 2‐pyridyl ketone oxime (mpko–) and azides (N3–) in non‐carboxylate Mn chemistry has afforded two new Mn6 clusters, [Mn6O3(N3)3(mpko)6(H2O)3](ClO4)2 (1) and [Mn6O3(N3)5(mpko)6(H2O)] (2), which are mixed‐valence (MnII, 5 MnIII). The 1:1:1:1 reaction of Mn(ClO4)2·6H2O, mpkoH, NaN3 and NEt3 in MeOH gave the cationic complex 1, while a similar reaction using additional NaO2CMe led instead to the neutral complex 2. The structurally unprecedented cores of the two cages are very similar, and contain the six Mn ions in a topology comprising three vertex‐sharing oxide‐centered triangles bridged by two end‐on azides. Variable‐temperature, solid‐state dc and ac magnetization studies were carried out for 1 and 2 in the 1.8–300 K range. The data reveal S = 5/2 ground states for both complexes, and fitting of magnetization vs. field (H) and temperature (T) data by matrix diagonalization for 1 gave S = 5/2, D = –1.4(3) cm–1, and g = 1.99(1), where D is the axial zero‐field splitting (ZFS) parameter. The combined results demonstrate the versatility of 2‐pyridyl ketone oxime anions in the presence of suitable ancillary ligands, such as azides, for the synthesis of new Mn clusters, without requiring the co‐presence of carboxylate ligands.
Indium‐Promoted Allylation Reaction of Imino‐Isatins in Aqueous Media: Synthesis of Quaternary 3‐Aminooxindoles
Authors: Alcaide Benito , Almendros Pedro , Aragoncillo Cristina 
Published: April 2010

AbstractQuaternary 3‐amino‐2‐oxindoles have been obtained viaallylation and propargylation reactions of imino‐isatins in aqueous media promoted by In and Zn respectively, under Barbier conditions, in good to excellent yields. A quaternary new stereocenter has been formed without hydrolysis of the starting imino‐isatin.
Ultrasound‐guided mechanical fragmentation of sialoliths (sonoguide forceps)
Authors: Geisthoff Urban W. , Maune Steffen 
Published: April 2010

AbstractBackgroundLittle data about the efficacy and limitations of ultrasound‐guided mechanical intraductal stone fragmentation and removal of sialoliths (Sonoguide Forceps) exist.MethodsThis was a chart review of patients treated within the last 4 years at 2 tertiary care centers.ResultsSonoguide Forceps were used as a second‐line treatment in 22 patients with sialolithiasis. Ten patients were free of stones and symptoms afterwards (7 of 17 submandibular, 2 of 4 parotid, 1 of 1 sublingual). Six patients were primarily treated for parotid sialolithiasis, 4 with successful stone retrieval. The reasons for failure were a lack of accessibility to the stone by the forceps (n = 9), the impossibility of grasping the stone (n = 5), and/or the concomitant grabbing of soft tissue together with the stone (n = 3).ConclusionThe efficacy of Sonoguide Forceps as both a secondary and primary treatment modality makes it an interesting, simple, and inexpensive therapeutic alternative. Relevant parameters for treatment success include the size and position of the stones. © 2010 Wiley Periodicals, Inc. Head Neck, 2010
Evaluation of lymphangiogenesis in premalignant conditions of the head and neck mucosa
Authors: Palomba Annarita , Gallo Oreste , Brahimi Arta , Franchi Alessandro 
Published: April 2010

AbstractBackgroundOur aim was to determine whether lymphangiogenesis occurs in the early steps of cancerogenesis of the upper aerodigestive tract.MethodsWe assessed the number of lymphatics per unit area (lymphatic vascular density [LVD]) and the percent area occupied by the lymphatic vessels (lymphatic vascular area [LVA]) by computer‐assisted morphometric analysis in 56 samples immunohistochemically stained with the lymphatic marker D2‐40. The results were compared to those obtained in 63 invasive squamous cell carcinomas.ResultsNo significant difference was observed between normal mucosa, hyperplasia/mild dysplasia, and moderate/severe dysplasia for LVD (p = .8) and LVA (p = .7). Conversely, invasive carcinomas presented a higher LVD than normal mucosa and precancerous lesions (p < .001), whereas there was no difference for LVA (p = .1).ConclusionLymphangiogenesis does not occur in premalignant lesions of the upper aerodigestive tract and it is rather a late event associated with the development of an invasive phenotype. © 2010 Wiley Periodicals, Inc. Head Neck, 2010
Visualizing meltwater flow through snow at the centimetre‐to‐metre scale using a snow guillotine
Authors: Williams Mark W. , Erickson Tyler A. , Petrzelka Jennifer L. 
Published: April 2010

AbstractMovement of liquid water through snowpacks remains one of the least understood aspects of snow hydrology. Liquid water movement through snowpacks is generally recognized to occur in distinct flow paths rather than as uniform flow through a homogeneous porous medium. Dye tracer experiments have been used in studies of meltwater flow through snow since the 1930s. Although dye tracer experiments have provided valuable qualitative information about meltwater pathways, quantitative descriptions of their spacing and location are not commonly available because of the difficulty in precisely excavating and measuring pathways. Here we provide a new proof‐of‐concept instrument we term a ‘snow guillotine’ that provides more quantitative information from dye tracer experiments conducted on melting snowpacks. Photographs are taken of each cross‐section over a 1‐m distance. Application of image processing and geostatistical analysis allows collection of high‐resolution (1 cm3), three‐dimensional data on meltwater flow through a snowpack.The results show preferential flowpaths, with the majority of vertical flow occurring in the upper 20–55 cm of the snowpack, while fewer preferential flowpaths are apparent below 100 cm. The number of vertical flowpaths in the upper half of the snowpack averaged almost 100 per m2, with the highest number of flowpaths reaching almost 300 per m2. Layer interfaces were found to significantly increase the volume of dye, indicating dominance by lateral flow at these boundaries. At each stratigraphic interface, the number of individual clusters decreased and it was more likely for a dyed pixel to be part of a large cluster. Geostatistical analyses showed that there were large increases in correlation lengths and the connectivity function at stratigraphic layers in contrast to low values between layers. For example, the buried ice layer in Experiment A at 169–170 cm showed separation distances of 20 cm. In contrast, two rows above this layer the separation distance was only 2 cm. Implementation of the snow guillotine provides the ability to conduct geostatistical analyses on field measurements of meltwater flow while providing three‐dimensional, quantitative data of unprecedented spatial resolution. Copyright © 2010 John Wiley & Sons, Ltd.
Mapping of road‐salt‐contaminated groundwater discharge and estimation of chloride load to a small stream in southern New Hampshire, USA
Authors: Harte Philip T. , Trowbridge Philip R. 
Published: April 2010

AbstractConcentrations of chloride in excess of State of New Hampshire water‐quality standards (230 mg/l) have been measured in watersheds adjacent to an interstate highway (I‐93) in southern New Hampshire. A proposed widening plan for I‐93 has raised concerns over further increases in chloride. As part of this effort, road‐salt‐contaminated groundwater discharge was mapped with terrain electrical conductivity (EC) electromagnetic (EM) methods in the fall of 2006 to identify potential sources of chloride during base‐flow conditions to a small stream, Policy Brook. Three different EM meters were used to measure different depths below the streambed (ranging from 0 to 3 m). Results from the three meters showed similar patterns and identified several reaches where high EC groundwater may have been discharging. Based on the delineation of high (up to 350 mmhos/m) apparent terrain EC, seven‐streambed piezometers were installed to sample shallow groundwater. Locations with high specific conductance in shallow groundwater (up to 2630 mmhos/m) generally matched locations with high streambed (shallow subsurface) terrain EC. A regression equation was used to convert the terrain EC of the streambed to an equivalent chloride concentration in shallow groundwater unique for this site. Utilizing the regression equation and estimates of one‐dimensional Darcian flow through the streambed, a maximum potential groundwater chloride load was estimated at 188 Mg of chloride per year. Changes in chloride concentration in stream water during streamflow recessions showed a linear response that indicates the dominant process affecting chloride is advective flow of chloride‐enriched groundwater discharge. Published in 2010 by John Wiley & Sons, Ltd.
Regional classification, variability, and trends of northern North Atlantic river flow
Authors: Kingston Daniel G. , Hannah, David M. , Lawler Damian M. , McGregor Glenn R. 
Published: April 2010

AbstractRegional classification techniques can help in identifying spatial structure in river flow variation. As such, a framework can be provided around which to test hypotheses, making regional classification an important tool for hydrological research, particularly over large and complex geographical domains. Here, the results of a regional classification of monthly river flow for the northern North Atlantic region over the period 1968–1997 are presented. Importantly, regional classes are identified on the basis of inter‐annual variation in river flow time series, rather than the more commonly used intra‐annual flow regime. This is beneficial because it provides an improved basis for the investigation of regional‐scale inter‐annual trends in river flow: an important aim given the potential for future changes in river discharge linked to climate change and land‐use change. Seven regions (four in northern Europe and three in eastern North America) are identified using hierarchical cluster analysis (Wards algorithm). Analysis of the hydrological homogeneity of the emergent river flow regions reveals them to be useful groupings to frame further analyses. Investigation of the statistical characteristics of each mean regional time series follows, including the annual flow regime, time series variability, and the presence of trends (as indicated by the Mann‐Kendall test). Key findings identified by the latter analysis include an increasing trend in late winter discharge for some northern European regions for 1968–1997, but overall few statistically significant trends. Copyright © 2010 John Wiley & Sons, Ltd.