bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cross‐Linked Amorphous Nitrilase Aggregates for Enantioselective Nitrile Hydrolysis
Authors: Kaul Praveen , Stolz Andreas , Banerjee U. C. 
Published: September 2007

AbstractA recombinant Escherichia coli strain was constructed which efficiently expressed the enantioselective nitrilase from Alcaligenes faecalis DSMZ 30030 as a hisitidine‐tagged enzyme variant under the control of a rhamnose inducible promoter. The enzyme was purified from cell extracts and used for the preparation of cross‐linked enzyme aggregates (CLEAs). The conditions for the preparation of the CLEAs were optimized using various organic solvents and cross‐linking agents and a procedure was developed which combined a precipitation with 85 % (v/v) isopropyl alcohol and a cross‐linking with 30 mM glutaraldehyde. Thus, about 80 % of the initial nitrilase activity could be incorporated into the CLEAs. The hydrolysis of racemic mandelonitrile to (R)‐mandelic acid was compared between the soluble nitrilase preparations and their CLEAs (nit‐CLEAs). The nitrilase activity in the CLEAs was at 30 °C and 60 °C about 5 times more stable than in the soluble preparations. The CLEAs could be reused 5 times with only about 10 % reduction in activity. The enantioselectivity of the nitrilase for the formation of (R)‐mandelic acid from racemic mandelonitrile decreased for both preparations with increasing temperatures (10 °C to 50 °C), but this effect was significantly less pronounced for the CLEAs. A detailed analysis of solvent effects on nitrilase enantioselectivity allowed thermodynamic insights into contributions from free energy component (activation enthalpy and entropy) to chiral preference of nitrilase in such non conventional media.
Social facilitation of fur rubbing behavior in white‐faced capuchins
Authors: Meunier H. , Petit O. , Deneubourg J.‐l. 
Published: September 2007

AbstractIn their natural environment, capuchins select certain plants, containing secondary compounds with bactericide, insecticide or fungicide properties, to rub their pelage energetically (i.e. fur rubbing). Fur rubbing can be performed in solitary, or collectively in subgroups of variable size and composition, and most of the time fur rubbing happens in synchrony with other group members. The aim of this study is to understand the underlying mechanisms of this phenomenon, and, more particularly, to determine the processes involved in its synchronization. For this purpose, we designed a set of experiments where white‐faced capuchins (Cebus capucinus) were presented with onions (Allium cepa) that they use to fur rub. We conducted a detailed kinetic study of fur rubbing behavior to determine if its synchronization is the consequence of simultaneous responses of different individuals to the same stimulus or if, on the contrary, there is a real collective phenomenon where individuals respond to conspecific behavior. Our results reveal that fur rubbing is a collective behavior with a mimetic underlying mechanism. If fur rubbing with onions (a plant with antifungal and repellent properties) allows capuchins to treat their fur against parasites or pathogens, its synchronization would optimize the treatment by acting as a group barrier to ectoparasite propagation. Am. J. Primatol. 70:161–168, 2008. © 2007 Wiley‐Liss, Inc.
Oligopotent Mesenchymal Stem Cell‐Like Clone Becomes Multinucleated Following Phorbol Ester, TPA Stimulation
Authors: Yoshida Keiichiro , Ono Michio , Maejima Tatsuo , Esaki Michiyo , Sawada Hajime 
Published: September 2007

AbstractWe established a mesenchymal stem cell clone, 5F9A, from rat bone marrow substrate adherent cells by repeated limiting dilutions. The cells have a fibroblastic shape and form intimate contacts with adjacent cells with interdigitations and junctions similar to adherence and tight junctions in a semi‐confluent culture. Analysis of the phenotypes of these cells by RT‐PCR and FACS demonstrated that they resembled mesenchymal stem cells, and the cells could differentiate into adiopocytes and osteoblasts under appropriate conditions in vitro showing their oligopotency. Furthermore, the cells were induced to become multinuclear cells by TPA (12‐o‐tetradecanoylphorbol 13‐acetate) stimulation. Anat Rec, 290:1256–1267, 2007. © 2007 Wiley‐Liss, Inc.
Cellular Motors for Molecular Manufacturing
Authors: Dinu C.Z. , Chrisey D.B. , Diez S. , Howard J. 
Published: September 2007

AbstractCells are composed of macromolecular structures of various sizes that act individually or collectively to maintain their viability and perform their function within the organism. This review focuses on one structure, the microtubule, and one of the motor proteins that move along it, conventional kinesin (kinesin 1). Recent work on the cellular functions of kinesins, such as the organization of microtubules during cellular division and the movement of the organelles and vesicles, offers insights into how biological motors might prove useful for organizing structures in engineered environments. Anat Rec, 290:1203–1212, 2007. © 2007 Wiley‐Liss, Inc.
Improving search engines by query clustering
Authors: Baeza‐Yates Ricardo , Hurtado Carlos , Mendoza Marcelo 
Published: September 2007

AbstractIn this paper, we present a framework for clustering Web search engine queries whose aim is to identify groups of queries used to search for similar information on the Web. The framework is based on a novel term vector model of queries that integrates user selections and the content of selected documents extracted from the logs of a search engine. The query representation obtained allows us to treat query clustering similarly to standard document clustering. We study the application of the clustering framework to two problems: relevance ranking boosting and query recommendation. Finally, we evaluate with experiments the effectiveness of our approach.
Mining Web functional dependencies for flexible information access
Authors: Perugini Saverio , Ramakrishnan Naren 
Published: September 2007

AbstractWe present an approach to enhancing information access through Web structure mining in contrast to traditional approaches involving usage mining. Specifically, we mine the hardwired hierarchical hyperlink structure of Web sites to identify patterns of term‐term co‐occurrences we call Web functional dependencies (FDs). Intuitively, a Web FD ‘x → y’ declares that all paths through a site involving a hyperlink labeled x also contain a hyperlink labeled y. The complete set of FDs satisfied by a site help characterize (flexible and expressive) interaction paradigms supported by a site, where a paradigm is the set of explorable sequences therein. We describe algorithms for mining FDs and results from mining several hierarchical Web sites and present several interface designs that can exploit such FDs to provide compelling user experiences.
Development and validation of a gas chromatography‐mass spectrometry method for the determination of phenazopyridine in rat plasma: application to the pharmacokinetic study
Authors: Chen Qinhua , Li Kaijun , Zhang Zhuo , Li Peng , Liu Jia , Li Qiang 
Published: September 2007

AbstractPhenazopyridine hydrochloride is a strong analgesic used in the treatment of urinary tract infections. The aim of the present study was to develop a procedure based on gas chromatography‐mass spectrometry (GC‐MS) for the analysis of phenazopyridine in rat plasma. The method was set up and adapted for the analysis of small biological samples taken from rats. Biological samples were extracted by liquid–liquid extraction. The extraction agent was ethyl acetate. The samples were separated by GC on a DB‐5MS analytical column and determined by a quadrupole mass spectrometer detector operated under selected ion monitoring mode. Excellent linearity was found between 0.01 and 1.00 µg/ml (r = 0.9991, n = 9) for plasma samples. The limit of detection (LOD) was 0.3 ng/ml. Within‐day and between‐day precisions expressed as the relative standard deviation (RSD) for the method were 1.83–4.91% and 2.12–4.76%, respectively. The recoveries for all samples were >90%. The main pharmacokinetic parameters obtained were Tmax = (0.35±0.01) h, Cmax = (0.396±0.079) µg/ml, AUC = (0.373±0.065) h µg/ml and CL = (94.2±5.9) ml/g/h. The results presented here clearly indicate that this proposed method could be applicable to investigate the pharmacokinetic of phenazopyridine in rats after administration. Copyright © 2007 John Wiley & Sons, Ltd.
Finding Y‐relevant part of X by use of PCR and PLSR model reduction methods
Authors: Ergon Rolf 
Published: September 2007

AbstractThe paper is considering the following question: using principal component regression (PCR) or partial least squares regression (PLSR), how much data can be removed from X while retaining the original ability to predict Y? Two model reduction methods using similarity transformations are discussed, one giving projections of original loadings onto the column space of the fitted response matrix $\hat {\bf Y}$ (essentially the orthogonal signal correction (OSC) methods), and one giving projections of original scores onto the column space of the coefficient matrix $\hat {\bf B}$ (essentially the net analyte signal (NAS) methods). The loading projection method gives model residuals that are orthogonal to Y and $\hat {\bf Y}$, which is valuable in certain applications. The score projection method, on the other hand, gives model residuals that are orthogonal to $\hat {\bf B}$, which is essential in other applications. It is shown that the reduced matrix X from the score projection method is a subset of the reduced matrix X from the loading projection method. It therefore has the smallest Frobenius norm, and thus the smallest total column variance, assuming centered data. Copyright © 2007 John Wiley & Sons, Ltd.
Long‐term results of a prospective study on the treatment of medulloblastoma in adults
Authors: Brandes Alba A. , Franceschi Enrico , Tosoni Alicia , Blatt Valeria , Ermani Mario 
Published: September 2007

AbstractBACKGROUND.Because medulloblastoma (MB) is rare in adults, the few studies on this condition have been retrospective, and the follow‐up has tended to be short. Furthermore, the different therapeutic strategies used in these patients has made it difficult to assess survival rates and prognostic factors.METHODS.In 1989, a prospective Phase II trial was initiated to evaluate the efficacy of treatment for adults with MB. Patients were staged completely with a neuroradiologic examination of the brain and neuroaxis and by cerebrospinal fluid cytology, according to Chang's staging system. Low‐risk patients received radiotherapy alone, whereas high‐risk patients received 2 cycles of upfront chemotherapy followed by radiotherapy and adjuvant chemotherapy. The current article reports on the long‐term results from that trial.RESULTS.After a median follow up of 7.6 years, among a total of 36 adults with MB, the overall progression‐free survival (PFS) and overall survival (OS) rates at 5 years were 72% and 75%, respectively. In low‐risk patients, the 5‐year PFS rate was 80%, and the 5‐year OS rate was 80%; in high‐risk patients, the 5‐year PFS rate was 69%, and the 5‐year OS rate was 73%.CONCLUSIONS.In adult patients with MB, long‐term follow‐up was essential for evaluating the real impact of treatments. Low‐risk and high‐risk patients did not differ significantly in terms of PFS or OS. Cancer 2007. © 2007 American Cancer Society.
Percentage of Gleason pattern 4 and 5 predicts survival after radical prostatectomy
Authors: Cheng Liang , Davidson Darrell D. , Lin Haiqun , Koch Michael O. 
Published: September 2007

AbstractBACKGROUND.Morphologic and clinical heterogeneity within tumor grades is well recognized in prostate cancer. The objective of the current study was to determine whether the combined percentage of Gleason patterns 4 and 5 in radical prostatectomy specimens is an independent predictor of cancer‐specific survival in prostate cancer patients.METHODS.The radical prostatectomy specimens were analyzed from 504 consecutive prostate cancer patients who were treated at Indiana University Medical Center between 1990 and 1998. Various clinical and pathologic characteristics were analyzed.RESULTS.A higher combined percentage of Gleason patterns 4 and 5 was associated with older age, higher preoperative serum prostate‐specific antigen level, higher pathologic stage, positive surgical margins, extraprostatic extension of tumor, higher Gleason score, perineural invasion, and lymph node metastasis. In the multivariate Cox regression model, the combined percentage of Gleason patterns 4 and 5 was found to be an independent predictor of cancer‐specific survival (P = .04).CONCLUSIONS.The combined percentage of Gleason patterns 4 and 5 is a powerful predictor of prostate cancer‐specific survival. Assessment of high‐grade cancer amounts may allow for better stratification of patients into appropriate prognostic groups and treatment protocols. Cancer 2007. © 2007 American Cancer Society.
Plasma‐Enhanced CVD for Particle Synthesis Using Circulating Fluidized Bed Technology
Authors: von Rohr P. R. , Borer B. 
Published: September 2007

AbstractCirculating fluidized beds (CFB) are widely used for gas‐solid reactions. This presentation summarizes specific design and operational features for a CFB system with a non‐thermal plasma. The results of coating a glass‐like material using salt particles as a model substrate are shown. The potential of the new technology is broad, due to the fact that plasma‐enhanced (PE)CVD can be used to combine and treat virtually any two different materials at low temperatures.
Aromatase expression and cell proliferation following injury of the adult zebra finch hippocampus
Authors: Peterson R. Scott , Fernando Gowry , Day Lainy , Allen Timothy A. , Chapleau Jeanette D. , Menjivar Jenny , Schlinger Barney A. , Lee Diane W. 
Published: September 2007

AbstractEstrogens can be neuroprotective following traumatic brain injury. Immediately after trauma to the zebra finch hippocampus, the estrogen‐synthetic enzyme aromatase is rapidly upregulated in astrocytes and radial glia around the lesion site. Brain injury also induces high levels of cell proliferation. Estrogens promote neuronal differentiation, migration, and survival naturally in the avian brain. We suspect that glia are a source of estrogens promoting cell proliferation after neural injury. To explore this hypothesis, we examined the spatial and temporal relationship between glial aromatase expression and cell proliferation after neural injury in adult female zebra finches. Birds were ovariectomized and given a blank implant or one filled with estradiol; some birds were also administered an aromatase inhibitor or vehicle. All birds received penetrating injuries to the right hippocampus. Twenty‐four hours after lesioning, birds were injected once with BrdU to label mitotically active cells and euthanized 2 h, 24 h, or 7 days later. The brains were processed for double‐label BrdU and aromatase immunocytochemistry. Injury‐induced glial aromatase expression was unaffected by survival time and aromatase inhibition. BrdU labeling was significantly reduced at 24 h by ovariectomy and by aromatase inhibition; effects were partially reversed by E2 replacement. Irrespective of ovariectomy, the densities of aromatase immunoreactive astrocytes and BrdU‐labeled cells at known distances from the lesion site were highly correlated. These data suggest that injury‐induced glial aromatization may influence the reorganization of injured tissue by providing a rich estrogenic environment available to influence cellular incorporation. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007.
XSUMO‐1 is required for normal mesoderm induction and axis elongation during early Xenopus development
Authors: Yukita Akira , Michiue Tatsuo , Danno Hiroki , Asashima Makoto 
Published: September 2007

AbstractThe small ubiquitin‐related modifier (SUMO) is a member of the ubiquitin‐like protein family, and SUMO conjugation (SUMOylation) resembles ubiquitination. Despite many SUMOylation target proteins being reported, the role of this system in vertebrate development remains unclear. We inhibited the function of Xenopus SUMO‐1 (XSUMO‐1) using a morpholino antisense oligo against XSUMO‐1 (XSUMO‐1‐MO) to clarify the role of SUMOylation. XSUMO‐1‐MO inhibited normal axis formation in embryos and elongation of activin‐treated animal caps. The expression of several mesoderm markers was reduced by XSUMO‐1‐MO. We measured activin‐like activity by using a reporter construct containing a multimer of activin‐responsive elements from the Goosecoid promoter, [DE(6x)Luc]. This assay showed that XSUMO‐1‐MO directly inhibited activin/nodal signaling. Furthermore, XSUMO‐1‐MO inhibited ectopic axis formation induced by XSmad2, and XSmad2/4 mRNA could not rescue the axis elongation defect induced by XSUMO‐1‐MO. These results suggested that XSUMO‐1 is required for normal axis elongation, at least partly mediating activin/nodal signaling. Developmental Dynamics 236:2757–2766, 2007. © 2007 Wiley‐Liss, Inc.
Neural MMP‐28 expression precedes myelination during development and peripheral nerve repair
Authors: Werner Sean R. , Mescher Anthony L. , Neff Anton W. , King Michael W. , Chaturvedi Shalini , Duffin Kevin L. , Harty Mark W. , Smith Rosamund C. 
Published: September 2007

AbstractMammalian matrix metalloproteinase 28 (MMP‐28) is expressed in several normal adult tissues, and during cutaneous wound healing. We show that, in frog and mouse embryos, MMP‐28 is expressed predominantly throughout the nervous system. Xenopus expression increases during neurulation and remains elevated through early limb development where it is expressed in nerves. In the mouse, neural expression peaks at embryonic day (E) 14 but remains detectable through E17. During frog hindlimb regeneration XMMP‐28 is not initially expressed in the regenerating nerves but is detectable before myelination. Following hindlimb denervation, XMMP‐28 expression is detectable along regenerating nerves before myelination. In embryonic rat neuron–glial co‐cultures, MMP‐28 decreases after the initiation of myelination. Incubation of embryonic brain tissue with purified MMP‐28 leads to the degradation of multiple myelin proteins. These results suggest that MMP‐28 plays an evolutionarily conserved role in neural development and is likely to modulate the axonal–glial extracellular microenvironment. Developmental Dynamics 236:2852–2864, 2007. © 2007 Wiley‐Liss, Inc.
Regulated expression of the ubiquitin protein ligase, E3Histone/LASU1/Mule/ARF‐BP1/HUWE1, during spermatogenesis
Authors: Liu Zhiqian , Miao Dengsheng , Xia Qingwen , Hermo Louis , Wing Simon S. 
Published: September 2007

AbstractA ubiquitin protein ligase (E3), E3Histone/LASU1 (Mule/ARF‐BP1/HUWE1), was recently identified that mediates ubiquitination of core histones, the Mcl‐1 anti‐apoptotic protein, and the p53 tumor suppressor protein. However, the expression of E3Histone/LASU1 remains poorly studied. Because we identified E3Histone/LASU1 from the testis, we explored its regulation during spermatogenesis. In the first wave of rat spermatogenesis, E3Histone/LASU1 mRNA and protein had peak expression at days 10 and 20, respectively, and decreased with age. Consistent with these findings, immunohistochemistry revealed that E3Histone/LASU1 was highly expressed in nuclei from spermatogonia to mid‐pachytene spermatocytes. There was no obvious staining in spermatids, when histones are ubiquitinated and degraded. E3Histone/LASU1 was also expressed in other tissues. However, except in neuronal cells of the brain, expression was cytoplasmic. Thus, E3Histone/LASU1 may play a role in chromatin modification in early germ cells of the testis, but also has functions in other tissues. Developmental Dynamics 236:2889–2898, 2007. © 2007 Wiley‐Liss, Inc.
Directing the differentiation of embryonic stem cells to neural stem cells
Authors: Cai Chunyu , Grabel Laura 
Published: September 2007

AbstractEmbryonic stem cells (ESCs) are a potential source of neural derivatives that can be used in stem cell‐based therapies designed to treat neurological disorders. The derivation of specific neuronal or glial cell types from ESCs invariably includes the production of neural stem cells (NSCs). We describe the basic mechanisms of neural induction during vertebrate embryogenesis and how this information helped formulate several protocols used to generate NSCs from ESCs. We highlight the advantages and disadvantages of each approach and review what has been learned about the intermediate stages in the transition from ESC to NSC. Recent data describing how specific growth factors and signaling molecules regulate production of NSCs are described and a model synthesizing this information is presented. Developmental Dynamics 236:3255–3266, 2007. © 2007 Wiley‐Liss, Inc.
The proliferating field of neural crest stem cells
Authors: Delfino‐Machín Mariana , Chipperfield Thomas R. , Rodrigues Frederico S.L.M. , Kelsh Robert N. 
Published: September 2007

AbstractNeural crest stem cells were first isolated from early embryonic neural crest in the early 1990s, but in the past 5 years, there has been a burst of discoveries of neural crest‐derived stem cells from diverse locations. Here, we summarize these data, highlighting the characteristics of each stem cell type. These cells vary widely in the markers they express and the variety of cell types they appear to generate. They occupy diverse locations, but in some cases multiple stem cell types apparently occupy physically proximate niches. To date, few molecular similarities can be identified between these stem cells, although a systematic comparison is required. We note other issues worthy of attention, including aspects of the in vivo behavior of these stem cells, their niches, and their lineage relationships. Together, analysis of these issues will clarify this expanding, but still young, field and contribute to exploration of the important therapeutic potential of these cells. Developmental Dynamics 236:3242–3254, 2007. © 2007 Wiley‐Liss, Inc.
Determination of copper(I) and copper(II) ions after complexation with bicinchoninic acid by CE
Authors: Basheer Chanbasha , Lee Hian Kee 
Published: September 2007

AbstractA facile, sensitive, and selective method was developed for the simultaneous separation and determination of copper(I) [Cu+] and copper(II) [Cu2+] ions using CE with direct UV detection. The copper ions were complexed with a 1.5 mM bicinchoninic acid disodium salt solution at pH 8.7 prior to analysis. Acetate buffer (2 mM) was used as the CE running buffer. Parameters affecting CE separation such as sample pH, applied voltage, concentration of complexing agent, nature of the buffer solution, and interferences by other metal ions, were evaluated. The LODs for Cu+ and Cu2+ were 3.0 and 2.5 μg/mL (S/N = 3), respectively. The developed method allows the simultaneous determination of Cu+ and Cu2+ in less than 5 min with RSDs of between 5.3 and 9.5% for migration time and between 3.4 and 9.7% for peak areas, respectively. At optimum conditions, the percentage recoveries of Cu+ and Cu2+ were found to be 99.4 and 99.5%.
Desorption of methy‐ethyl‐ketone from granular activated carbon with microwave radiation
Authors: Tai Hua‐Shan , Lee Chien‐li 
Published: September 2007

AbstractGranular‐activated carbon (GAC) is an excellent microwave (MW) absorbing material to absorb and convert MW energy into thermal energy. The removal of adsorbed methyl ethyl ketone (MEK) on GAC for regenerating the saturated GAC using MW energy was presented in this article. The result shows that the treatment time for achieving 80% desorption efficiency using 200‐W MW power output is 4 min for 5 g MEK adsorbed on 5 g GAC and 6 min for 3 g MEK adsorbed on 5 g GAC. The MW treatment recovers the adsorbed MEK from the inner pores of the carbon granules to restore the original adsorption capacity and surface area of the activated carbon. The MW‐induced regeneration allows the saturated GAC to be regenerated on site and provides an economic method to remove and destroy solvents emitted from small sources by using the GAC‐bed treatment. © 2007 American Institute of Chemical Engineers Environ Prog, 2007