bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dynamics of Polycomb and Trithorax activities during development
Authors: Soshnikova Natalia 
Published: February 2011

AbstractDynamic changes in gene expression are tightly controlled during development, as a single totipotent zygote gives rise to distinct cell lineages. The establishment and maintenance of these diverse transcriptional programs rely on changes of chromatin state, mainly through histone modifications. Polycomb and Trithorax complexes participate in setting apart active and inactive genes by respectively repressing and activating key developmental regulators in different cell types. Over the last decade, our understanding of the biochemical mechanisms underlying their activities has greatly improved, but the signals targeting these proteins to specific regions of the genome are still poorly understood, particularly in vertebrates. Recent findings highlight the highly dynamic activities of Polycomb and Trithorax complexes in vivo. Surprisingly, although their role in transcriptional regulation is deeply conserved during evolution, the time sequence in which they act seems to vary across species. Birth Defects Research (Part A), 2011. © 2011 Wiley‐Liss, Inc.
Signalling pathways and the host‐parasite relationship: Putative targets for control interventions against schistosomiasis
Authors: You Hong , Gobert Geoffrey N. , Jones Malcolm K. , Zhang Wenbao , McManus Donald P. 
Published: February 2011

AbstractA better understanding of how schistosomes exploit host nutrients, neuro‐endocrine hormones and signalling pathways for growth, development and maturation may provide new insights for improved interventions in the control of schistosomiasis. This paper describes recent advances in the identification and characterisation of schistosome tyrosine kinase and signalling pathways. It discusses the potential intervention value of insulin signalling, which may play an important role in glucose uptake and carbohydrate metabolism in schistosomes, providing the nutrients essential for parasite growth, development and, notably, female fecundity. Significant progress has also been made in the characterisation of other schistosome growth factor receptors, such as transforming growth factor beta receptor and epidermal growth factor receptor, and in our understanding of their roles in the host‐parasite molecular dialogue and parasite development. The use of parasite signal transduction components as novel vaccine or drug targets may prove invaluable in prevention, treatment and control strategies to combat schistosomiasis.
How will fish that evolved at constant sub‐zero temperatures cope with global warming? Notothenioids as a case study
Authors: Patarnello Tomaso , Verde Cinzia , di Prisco Guido , Bargelloni Luca , Zane Lorenzo 
Published: February 2011

AbstractCurrent climate change has raised concerns over the fate of the stenothermal Antarctic marine fauna (animals that evolved to live in narrow ranges of cold temperatures). The present paper focuses on Notothenioidei, a taxonomic group that dominates Antarctic fish. Notothenioids evolved in the Southern Ocean over the last 20 million years, providing an example of a marine species flock with unique adaptations to the cold at morphological, physiological and biochemical levels. Their phenotypic modifications are often accompanied by ‘irreversible’ genomic losses or gene amplifications. On a micro‐evolutionary scale, relatively ‘shallow’ genetic variation is observed, on account of past fluctuations in population size, and a significant genetic structure is evident, suggesting low population connectivity. These features suggest that Antarctic fish might have relatively little potential to adapt to global warming, at least at a genetic level. The extent of their phenotypic plasticity, which is evident to some degree, awaits further research.
Effectiveness of an instructional DVD in training college students to implement functional analyses
Authors: Trahan Maranda A. , Worsdell April S. 
Published: February 2011

AbstractA functional analysis is a valuable assessment technique that requires a unique kind of precision on behalf of the therapist. However, there is a lack of empirically validated tools for training functional analysis skills. This study examined the effectiveness of an instructional DVD in training college students to perform five functional analysis conditions. During simulated sessions, participants acted as therapists, and observers measured the accuracy with which they implemented programmed antecedents and consequences. Results showed that the DVD was effective in improving all participants' accuracy above baseline levels; however, in order to meet the 90% performance criterion, all participants required feedback. These results suggest that an instructional video is a useful training tool in providing basic skills for conducting functional analyses. Copyright © 2011 John Wiley & Sons, Ltd.
Flow cytometric analysis of glyoxalase‐1 expression in human leukocytes
Authors: Skapare Elina , Riekstina Una , Liepinsh Edgars , Konrade Ilze , Makrecka Marina , Maurina Baiba , Dambrova Maija 
Published: February 2011

AbstractAltered glyoxalase‐1 (GLO‐1) activity and expression is associated with the development of late diabetic complications, malignancy and oxidative stress‐ and aging‐related diseases. In the present study, we developed a flow cytometry method for GLO‐1 detection in human leukocytes isolated from peripheral blood samples to investigate GLO‐1 expression in leukocyte subsets from type 1 and 2 diabetes mellitus patients (n = 11) and healthy subjects (n = 8). The flow cytometry analysis of GLO‐1 in leukocytes showed that expression index of GLO‐1‐positive cells was slightly increased in mononuclear leukocytes from diabetic patients. This result correlated with the increase in GLO‐1 activity in the whole blood samples of type 2 diabetes patients. In conclusion, the present study demonstrates that flow cytometry is suitable for the detection of the GLO‐1 enzyme in human leukocytes and that this method could be used to investigate the fast adaptation of the glyoxalase system related to the pathogenesis of late complications of diabetes mellitus and other glycation stress‐related disorders. Copyright © 2011 John Wiley & Sons, Ltd.
Estrogen receptor alpha is essential for the proliferation of prostatic smooth muscle cells stimulated by 17β‐estradiol and insulin‐like growth factor 1
Authors: Zhou Dawei , Li Shiwen , Wang Xinghuan , Cheng Bei , Ding Xiegang 
Published: February 2011

AbstractEstradiol (E2) and its receptor estrogen receptor alpha (ERα) are implicated in the pathology of stromal‐predominant benign prostatic hyperplasia (BPH). Insulin‐like growth factor 1(IGF1) is produced primarily by stromal cells in the prostate. Recent study showed that E2‐mediated regulation of IGF1 in mouse uterus requires the DNA binding ability of ERα. However, the crosstalk between ERα and IGF1 in the prostate has not been addressed yet. Therefore, in this study we employed mouse prostatic smooth muscle cells (PSMCs) as a model to demonstrate that E2 stimulated the proliferation of PSMCs and up‐regulated the expression of IGF1 and its receptor IGF1R as well as cyclin D1 in PSMCs, all of which could be inhibited by shRNA‐mediated knockdown of ERα. Furthermore, we found that exogenous IGF1 could not promote cell proliferation and cyclin D1 expression in PSMCs subjected to shRNA‐mediated knockdown of ERα. Interestingly, blockage of IGF1R by antibody could inhibit E2‐stimulated PSMCs proliferation. Altogether our present study provides the first line of evidence that there is crosstalk between ERα and IGF1 signaling in PSMCs proliferation in which ERα up‐regulates the expression of IGF1 and IGF1R, and IGF1 signaling is indispensable to mediate downstream effects of E2 and ERα. Copyright © 2011 John Wiley & Sons, Ltd.
Effects of structural analogues of nociceptin(1–13)NH2 on brain antioxidant status in kainic acid‐treated rats
Authors: Tzvetanova Elina , Nenkova Galina , Georgieva Almira , Alexandrova Albena , Girchev Radoslav , Kirkova Margarita 
Published: February 2011

AbstractThe in vivo effects of nociceptin (N/OFQ(1–13)NH2) and its structural analogues ([Dab9]N/OFQ(1–13)NH2, [Dap9]N/OFQ(1–13)NH2 and [Cav9]N/OFQ(1–13)NH2) on the levels of lipid peroxidation and cell antioxidants (enzyme and non‐enzyme) in brain of control and kainic acid (KA)‐treated rats were studied. In control animals, [Dab9]N/OFQ(1–13)NH2 and [Dap9]N/OFQ(1–13)NH2, unlike N/OFQ(1–13)NH2 and [Cav9]N/OFQ(1–13)NH2, slightly increased the brain lipid peroxidation; the rest of the parameters were unchanged by all neuropeptides tested. KA (0.25 µg in 0.5 µl, i.c.v) increased the lipid peroxidation (4 and 24 h after KA‐injection) and decreased the glutathione level (1 h after KA‐administration). One hour after KA‐administration, the neuropeptides (2 µg in 0.5 µl, injected 30 min before KA) showed the following effects: a slight decrease in the KA‐induced lipid peroxidation by all nociceptin analogues and an enhancement of the KA‐decreased GSH level, but by [Cav9]N/OFQ(1–13)NH2 only. The brain antioxidant enzyme activities were unchanged in all used experimental groups. In addition, the nociceptin analogues, especially [Can9]N/OFQ(1–13)NH2, showed a good antioxidant capacity in chemical systems, generating reactive oxygen species. In conclusion, the substitution of lysin (Lys) in N/OFQ(1–13)NH2 molecule with other amino acids might contribute to changes in its antioxidant properties. Copyright © 2011 John Wiley & Sons, Ltd.
Stacked PLS for calibration transfer without standards
Authors: Ni Wangdong , Brown Steven D. , Man Ruilin 
Published: February 2011

AbstractWe report the successful application of stacked partial least‐squares (SPLS) regression for direct application of multivariate calibration models to data from a secondary spectrometer, without use of any calibration transfer. Unlike a conventional calibration that requires transfer methods which need measurement of a set of transfer samples to make useful predictions from data obtained on a secondary instrument, SPLS regression can be used to generate regression models with good predictive power on both primary and secondary instruments. Results of direct application of SPLS to lake sediment data without use of any transfer standards show predictive results comparable to those obtained from conventional PLS calibration followed by a model updating (MUP) step. We also demonstrate the use of calibration MUP applied to stacked PLS regression, which further minimizes local differences between two instruments. Copyright © 2011 John Wiley & Sons, Ltd.
Novel and Efficient Copper‐Catalysed Synthesis of Nitrogen‐Linked Medium‐Ring Biaryls
Authors: Kenwright Jayne L. , Galloway Warren R. J. D. , Blackwell David T. , Isidro‐Llobet Albert , Hodgkinson James , Wortmann Lars , Bowden Steven D. , Welch Martin , Spring David R. 
Published: February 2011

AbstractHerein, a new copper‐catalysed strategy for the synthesis of rare nitrogen‐linked seven‐, eight‐ and nine‐membered biaryl ring systems is described. It is proposed that the reaction proceeds through a highly activated intramolecularly co‐ordinated copper catalyst. The process is technically simple, proceeds under relatively mild conditions, displays a broad substrate scope and forms biologically valuable products that are difficult to synthesise by other methods. We envisage that this methodology will prove useful in a wide synthetic context, with possible applications in both target‐oriented and diversity‐oriented synthesis.
Lob des CO2. Das verrufene Gas
Authors: Soentgen Jens 
Published: February 2011

AbstractDie in der öffentlichen Diskussion verbreitete Charakterisierung von CO2 als Klimakiller wird in diesem Essay als Projektion kritisiert: Mit der Vokabel “Klimakiller” wird aus einem politischen und kulturellen Problem ein technisches gemacht. Zugleich wird der Blick auf das CO2 selbst verstellt. Daher stellt sich der Autor in die Tradition der enkomia paradoxa, der paradoxen Lobreden und stimmt eine Laudatio auf das CO2 an. Er zieht dazu Fakten aus der Religionsgeschichte, aus der Wissenschaftsgeschichte, aus der Kulturgeschichte und insbesondere aus der ökologischen Chemie heran und stellt sie in einen größeren Zusammenhang. Ziel ist es, durch notwendige Provokationen zu einem realitätsnäheren Bild des Stoffes CO2 zu gelangen. Experimente mit CO2, darunter auch das einfachstmögliche Experiment zum Treibhauseffekt, ergänzen die Darstellung.
Raman‐Spektroskopie. Biomedizinische Diagnostik
Authors: Schmitt Michael , Popp Jürgen 
Published: February 2011

AbstractDie Raman‐Mikrospektroskopie hat sich in den letzten Jahren aufgrund ihrer Labelfreiheit und ihrer hohen molekularen Selektivität als extrem leistungsstarke Analysenmethode für die biomedizinische Diagnostik etabliert. So gelingt es mittels der Raman‐Mikrospektroskopie Mikroorganismen wie bakterielle Krankheiterreger auf Einzelzellebene schnell zu identifizieren und charakterisieren. Lineare Raman‐Spektroskopie und nichtlineare Raman‐Techniken wie die CARS‐Mikroskopie besitzen großes Potenzial zur objektiven Beurteilung von Zellen oder Gewebe zur Frühdiagnose von Krankheiten wie Krebs.
Ein Elektronisches Laborjournal
Authors: Gooßen Lukas , Rudolphi Felix 
Published: February 2011

AbstractMancher Chemiker wird sich fragen, warum wir heutzutage Briefe mit dem Computer schreiben, unsere Zeitung im Internet lesen, aber unsere Experimente und Beobachtungen in vielen Fällen von Hand in Laborbüchern beschreiben. Warum verzichten wir an dieser Stelle auf die Vorzüge der Computertechnik?
Mangan
Authors: Schwedt Georg 
Published: February 2011

AbstractDas seit fast 200 Jahren bestehende Mineralogische Museum der Universität Bonn, das 1874 eine bedeutende Sammlung vom Gründer des heutigen Rheinischen Mineralien‐Kontors A. Krantz erhielt, zeigt unter anderem systematisch geordnet Minerale zu ausgewählten chemischen Elementen. Sie werden in dieser Serie zum Internationalen Jahr der Chemie 2011 näher vorgestellt.
Das Diamant‐Gitter, Kristallstrukturen und Molekül‐Modelle
Authors: Quadbeck‐Seeger Hans‐Jürgen 
Published: February 2011

AbstractDie Bemühungen, kostengünstige Molekül‐Modelle für Schule und Studium zu entwerfen, haben zu ungewöhnlichen Ergebnissen geführt. Das Ziel ist einfach und klar: Junge Menschen sollen sich eigene Modelle bauen können, die das räumliche Vorstellungsvermögen fördern und fordern. Die Wege von den anfänglichen DNA‐Modellen zu einer Reihe von interessanten, jedermann zugänglichen Konzepten verliefen – und das ist charakteristisch für Innovationen – alles andere als geradlinig.
Nanopartikel zur Rettung von Maya‐Kulturschätzen
Authors: Groß Michael 
Published: February 2011

AbstractWandmalereien hat man im 20. Jahrhundert gern zu ihrem Schutz mit Kunststoff versiegelt, doch inzwischen haben Forscher herausgefunden, dass solche Maßnahmen oft mehr schaden als nutzen. Eine neue Lösung bieten Nanopartikel aus Calcium‐ und Bariumhydroxid.
Surface functionalization of superparamagnetic nanoparticles for the development of highly efficient magnetic resonance probe for macrophages
Authors: Huang Chao , Neoh Koon Gee , Wang Liang , Kang En‐Tang , Shuter Borys 
Published: February 2011

AbstractIn vivo magnetic resonance imaging (MRI) tracking of macrophages plays an important role in monitoring and understanding numerous human diseases with high macrophage activity. In this work, superparamagnetic iron oxide nanoparticles (SPIONs) of ∼12 nm were surface‐functionalized with poly(DL‐lactic acid‐co‐malic acid) copolymer (PLMA) via a nanoprecipitation method. The r1, r2 and r2/r1 values of the PLMA‐SPIONs obtained at a magnetic field of 3 T were 0.38, 196 and 516 mM−1 s−1, respectively. The high r2/r1 ratio can be expected to provide enhanced MR contrast. The PLMA‐SPIONs were readily taken in by macrophages and the high iron uptake was confirmed via Prussian Blue staining and quantified by inductively coupled plasma mass spectrometry (ICP‐MS). No significant cytotoxicity was found even at a high nanoparticle loading of 67.7 pg Fe per cell. A linear relationship between R2 and R values and the number of PLMA‐SPIONs labeled cells was observed in vitro. As a result of the significantly higher R than R2 effects, an in vitro detection threshold of about 2820 labeled cells was achieved with short labeling time and low nanoparticle concentration using a clinical 3 T MRI scanner. Thus, the PLMA‐SPIONs can be potentially useful as magnetic resonance probes for targeting and tracking macrophages. Copyright © 2011 John Wiley & Sons, Ltd.
Structure, microstructure and magnetic properties of mixed rare earth oxide (Dy1‐xErx)2O3
Authors: Heiba Z. K. , Bakr Mohamed M. , Abdelslam M. A. , Fuess L. H. 
Published: February 2011

AbstractThe mixed rare earth oxide (Dy1‐xErx)2O3 (0.0 ≤ x ≤ 1.0) were synthesized by a sol–gel process. X‐ray and neutron diffraction data were collected and crystal structure and microstructure analyses were performed using Rietveld refinement method. All samples were found to have the same crystal structure and formed solid solutions over the whole range of x. Preferential cationic distribution is found for all samples but with different extent with Dy3+ preferring the 8b among the two non‐equivalent sites 8b and 24d of the space group Ia3. The lattice parameter is found to vary linearly with the composition x and a systematic variation is found in the r.m.s microstrain $ \langle \epsilon^2_{\rm L} \rangle^{1/2} $. Magnetization measurements were done in the temperature range 5‐300 K and a behavior in accordance with Curie‐Weiss law was found. Anomalous concentration dependence is found in magnetic susceptibility which is ascribed to the concentration dependence of effective crystal field combined with the contribution of 4I15/2 and 6H15/2 manifold at elevated temperature. The effective magnetic moments μeff is found to decrease linearly with composition parameter x, except for sample x=0.5 where the magnetization is enhanced. The Curie‐Weiss paramagnetic temperatures indicated antiferromagnetic interaction. These magnetic results are discussed in view of the cationic distribution. (© 2011 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
A novel chemiluminescence quenching method for determination of sulfonamides in pharmaceutical and biological fluid based on luminol–Ag(III) complex reaction in alkaline solution
Authors: Sun Hanwen , Chen Peiyun , Li Liqing , Cheng Peng 
Published: February 2011

AbstractA novel chemiluminescence (CL) quenching method for the determination of sulfonamides is proposed. The CL reaction between Ag(III) complex [Ag(HIO6)2]5− and luminol in alkaline solution was investigated. The quenching effect of sulfonamides on CL emission of [Ag(HIO6)2]5−–luminol system was found. Quenching degree of CL emission was proportional to sulfonamide concentration. The effects of the reaction conditions on CL emission and quenching were examined. Under optimal conditions, the detection limits (s/n = 3) were 7.2, 17 and 8.3 ng/mL for sulfadiazine, sulfameter, and sulfadimethoxine, respectively. The recoveries of the three drugs were in the range of 91.3–110% with RSDs of 1.9–2.7% for urine samples, and 106–112% with RSDs of 1.6–2.8% for serum samples. The proposed method was used for the determination of sulfadiazine at clinically relevant concentrations in real urine and serum samples with satisfactory results. Copyright © 2011 John Wiley & Sons, Ltd.
Spectral data analyses and structure elucidation of metoprolol tartrate
Authors: Qiao Jun‐qin , Wang Ya‐qin , Liu Chen‐chen , Zhu Wei , Lian Hong‐zhen , Ge Xin 
Published: February 2011

AbstractThe infrared spectrum, ultraviolet spectrum, mass spectra, and nuclear magnetic resonance spectra of metoprolol tartrate, an antiarrhythmic medicine, were reported and interpreted comprehensively. The vibrations of functional groups in infrared spectrum, electron transitions in ultraviolet spectrum, and main characteristic fragmentations in mass spectra of metoprolol tartrate were discussed. All the 1H and 13C NMR chemical shifts were assigned by means of distoritionless enhancement by polarization transfer‐135 and ‐90, 1H‐1H correlation spectroscopy, and 13C‐1H correlation spectroscopy via short‐ and long‐range coupling. Copyright © 2011 John Wiley & Sons, Ltd.
Spatiotemporal changes in cell adhesiveness during vertebrate limb morphogenesis
Authors: Wada Naoyuki 
Published: February 2011

AbstractDuring vertebrate limb development, various molecules are expressed in the presumptive limb field or the limb bud in a spatiotemporal‐specific manner. The combination of these molecules regulates cellular properties that affect limb initiation and its morphogenesis, especially cartilage formation. Cell adhesiveness of the limb mesenchyme is a key factor in the regulation of cell distribution. Differential adhesiveness of mesenchymal cells is first observed between cells in the presumptive limb field and flank region, and the adhesiveness of the cells in the limb field is higher than that of cells in the flank region. In the limb bud, the adhesiveness of mesenchymal cells shows spatiotemporal difference, which reflects the positional identity of the cells. Position‐dependent cell adhesiveness is also observed in blastema cells of the regenerating limb. Therefore, local changes in cell adhesiveness are observed during limb development and regeneration, suggesting significant roles for cell adhesiveness in limb morphogenesis. Developmental Dynamics 240:969–978, 2011. © 2011 Wiley‐Liss, Inc.
Looking proximally and distally: 100 years of limb regeneration and beyond
Authors: Stocum David L. , Cameron Jo Ann 
Published: February 2011

AbstractThe experimental study of amphibian limb regeneration spans most of the 20thcentury and the first decade of the 21stcentury. We first review the major questions investigated over this time span: (1) the origin of regeneration blastema cells, the mechanism of tissue breakdown that liberates cells from their tissue organization to participate in blastema formation, (3) the mechanism of dedifferentiation of these cells, (4) how the blastema grows, (5) how the blastema is patterned to restore the missing limb structures, and (6) why adult anurans, birds and mammals do not have the regenerative powers of urodele salamanders. We then look forward in a perspective to discuss the many unanswered questions raised by investigations of the past century, what new approaches can be taken to answer them, and what the prospects are for translation of basic research on limb regeneration into clinical means to regenerate human appendages. Developmental Dynamics 240:943–968, 2011. © 2011 Wiley‐Liss, Inc.
Expression of key retinoic acid modulating genes suggests active regulation during development and regeneration of the amphibian limb
Authors: McEwan James , Lynch Joshua , Beck Caroline W. 
Published: February 2011

AbstractWe have previously shown differential regulation of components of the Retinoic acid (RA) pathway in Xenopus tadpole hindlimb regeneration. RA is thought to act as a morphogen, providing positional information during development and regeneration. We have investigated the regulation of genes involved in RA synthesis, catabolism, and binding in developing and regenerating Xenopus limbs. Our data indicate that RA is synthesised by Raldh2 in proximal cells during limb bud outgrowth. Furthermore, Cyp26b is expressed transiently in the progress zone of developing limbs and the blastema of regenerating limbs suggesting degradation of RA occurs in both processes. The RA‐binding protein Crabp2 is also upregulated during regeneration. We summarise this data to predict the presence of evolving gradients of RA in the developing amphibian limb. Thus, RA from the stump cells could be responsible for the establishment of proximal‐distal pattern during limb regeneration, as predicted by classical studies. Developmental Dynamics 240:1259–1270, 2011. © 2011 Wiley‐Liss, Inc.