bluuebunny/crossref_metadata_2025 huggingface dataset:
Efficacy of gabapentin in the management of chemotherapy‐induced peripheral neuropathy
Authors: Rao Ravi D. , Michalak John C. , Sloan Jeff A. , Loprinzi Charles L. , Soori Gamini S. , Nikcevich Daniel A. , Warner David O. , Novotny Paul , Kutteh Leila A. , Wong Gilbert Y. ,   and the North Central Cancer Treatment Group
Published: September 2007

BACKGROUND.

The antiepileptic agent, gabapentin, has been demonstrated to relieve symptoms of peripheral neuropathy due to various etiologies. On the basis of these data, a multicenter, double‐blind, placebo‐controlled, crossover, randomized trial was conducted to evaluate the effect of gabapentin on symptoms of chemotherapy‐induced peripheral neuropathy (CIPN).

METHODS.

Patients with symptomatic CIPN who complained of ‘average’ daily pain scores of either 1) ≥4 on a 0–10 numerical rating scale (NRS); or 2) ≥1 on the 0–3 Eastern Cooperative Oncology Group neuropathy scale (ENS) were eligible (higher numbers indicate greater severity of symptoms in both scales). Patients were randomized to receive gabapentin (target dose, 2700 mg) or placebo for 6 weeks. Crossover occurred after a 2‐week washout period. CIPN‐related symptoms were evaluated weekly by questionnaires. Statistical methods followed established methods for crossover designs, including Student t tests to compare average intrapatient differences between treatments and linear models to adjust for potential concomitant covariates.

RESULTS.

There were 115 patients who were randomly assigned to the treatment or control arm. Both groups were well matched by symptoms at study entry. Changes in symptom severity were statistically similar between the 2 groups during the study. Adverse events were mild and similar in both groups.

CONCLUSIONS.

This trial failed to demonstrate any benefit to using gabapentin to treat symptoms caused by CIPN. Cancer 2007. © 2007 American Cancer Society.
Race, biochemical disease recurrence, and prostate–specific antigen doubling time in the SEARCH database
Authors: Powell Isaac
Published: September 2007

In their study in the current issue of Cancer, Hamilton et al. attempt to resolve conflicting data regarding prostate cancer and racial outcomes. The most interesting findings include a significantly younger population of black men with higher prostate–specific antigen levels, similar tumor grade, and less extracapsular extension, yet with a higher rate of biochemical disease recurrence compared with white men. Recent genetic studies have reported that variants on chromosome 8q24 and CYP3A4 on chromosome 7 are associated with aggressive prostate cancer in young black men.
Comparative localization of cystathionine β‐synthase and cystathionine γ‐lyase in retina: Differences between amphibians and mammals
Authors: Pong Winnie W. , Stouracova Renata , Frank Nina , Kraus Jan P. , Eldred William D.
Published: September 2007

Hydrogen sulfide (H2S) is a gaseous neuromodulator that can be synthesized by the transsulfuration enzymes cystathionine β‐synthase (CBS) and cystathionine γ‐lyase (CGL). In this study we examined H2S as a potential neuromodulator in vertebrate retina. CBS‐like immunoreactivity (LI) was found in somas in the inner nuclear layer and as punctate staining in the inner and outer plexiform layers in the salamander retina. CGL‐LI was most clearly characterized in salamander, where it was localized in Müller cells. Western blots indicated proteins with the correct molecular weights for both enzymes in both species for liver and cerebellum. Correct molecular weight proteins were identified for both CGL and CBS in salamander retina. The CBS antiserum did not recognize the correct molecular weight protein in mouse retina but the CGL antiserum recognized the correct molecular weight protein for mouse retina. Enzyme assays indicated both CGL and CBS enzyme activity in all three tissues in the salamander. There was good CBS activity in the liver and cerebellum of the mouse but no activity in the retina. CGL activity was clearly present only in the mouse liver, with only trace activity in the cerebellum and retina. In conclusion, both CBS and CGL are present in the amphibian retina, which suggests either a potential role for H2S as a gaseous neuromodulator in both neurons and glia in the retina or a requirement for cysteine and glutathione synthesis via the transsulfuration pathway as a defense against oxidative stress. J. Comp. Neurol. 505:158–165, 2007. © 2007 Wiley‐Liss, Inc.
Dynamic features of postnatal subventricular zone cell motility: A two‐photon time‐lapse study
Authors: Nam Sang Chae , Kim Yongsoo , Dryanovski Dilyan , Walker Avery , Goings Gwendolyn , Woolfrey Kevin , Kang Seong Su , Chu Chris , Chenn Anjen , Erdelyi Ferenc , Szabo Gabor , Hockberger Philip , Szele Francis G.
Published: September 2007

Neuroblasts migrate long distances in the postnatal subventricular zone (SVZ) and rostral migratory stream (RMS) to the olfactory bulbs. Many fundamental features of SVZ migration are still poorly understood, and we addressed several important questions using two‐photon time‐lapse microscopy of brain slices from postnatal and adult eGFP+ transgenic mice. 1) Longitudinal arrays of neuroblasts, so‐called chain migration, have never been dynamically visualized in situ. We found that neuroblasts expressing doublecortin‐eGFP (Dcx‐eGFP) and glutamic acid decarboxylase‐eGFP (Gad‐eGFP) remained within arrays, which maintained their shape for many hours, despite the fact that there was a wide variety of movement within arrays. 2) In the dorsal SVZ, neuroblasts migrated rostrocaudally as expected, but migration shifted to dorsoventral orientations throughout ventral regions of the lateral ventricle. 3) Whereas polarized bipolar morphology has been a gold standard for inferring migration in histologic sections, our data indicated that migratory morphology was not predictive of motility. 4) Is there local motility in addition to long distance migration? 5) How fast is SVZ migration? Unexpectedly, one‐third of motile neuroblasts moved locally in complex exploratory patterns and at average speeds slower than long distance movement. 6) Finally, we tested, and disproved, the hypothesis that all motile cells in the SVZ express doublecortin, indicating that Dcx is not required for migration of all SVZ cell types. These data show that cell motility in the SVZ and RMS is far more complex then previously thought and involves multiple cell types, behaviors, speeds, and directions. J. Comp. Neurol. 505:190–208, 2007. © 2007 Wiley‐Liss, Inc.
Displaced amacrine cells of the mouse retina
Authors: Pérez De Sevilla Müller Luis , Shelley Jennifer , Weiler Reto
Published: September 2007

The aim of this study was to characterize and classify the displaced amacrine cells in the mouse retina. Amacrine cells in the ganglion cell layer were injected with fluorescent dyes in flat‐mounted retinas. Dye‐filled displaced amacrine cells were classified according to dendritic field size, horizontal and vertical stratification patterns, and general morphology. We identified 10 different morphological types of displaced amacrine cell. Six of the cell types identified here are novel cell types that have not been described previously in the mouse retina, to the best of our knowledge. The displaced amacrine cells included four types of medium‐field cells, with dendritic field diameters of 200–500 μm, and six types of wide‐field cells, with dendritic fields extending over 500 μm. Narrow‐field displaced amacrine cells, with dendritic field diameters smaller than 200 μm, were not encountered. The most frequently labeled displaced amacrine cell type was the starburst amacrine cell. At least three cell types identified here have nondisplaced counterparts in the inner nuclear layer as well. Displaced amacrine cells display a rich variety of stratification and branching patterns, which surely reflect the wide range of their functional roles in the processing of visual signals in the inner retina. J. Comp. Neurol. 505:177–189, 2007. © 2007 Wiley‐Liss, Inc.
Evidence for constitutive neural cell proliferation in the adult murine hypothalamus
Authors: Kokoeva Maia V. , Yin Huali , Flier Jeffrey S.
Published: September 2007

Compelling evidence suggests that the mammalian brain is capable of generating new neurons throughout adult life. While neurogenesis can be induced at various brain sites by exogenous cues, constitutive birth of new neurons has been unambiguously demonstrated within the subventricular zone (SVZ) of the lateral ventricles and the subgranular zone (SGZ) of the dentate gyrus. The lack of strong evidence that constitutive neurogenesis occurs elsewhere in the adult brain could be due to its exclusive restriction to the SVZ and SGZ or, for instance, to the inadequacy of the methods used to reveal new‐born neurons at other brain sites. By using intracerebroventricular (icv) delivery of the mitotic marker bromodeoxyuridine (BrdU) we demonstrate that new cells are born continuously and in substantial numbers in the adult murine hypothalamus and that many of these cells appear to differentiate into neurons as assessed by the expression of doublecortin (Dcx) and other neuronal fate markers. As compared to intraperitoneal (ip) BrdU injections, central BrdU infusion also uncovers a higher‐fold induction of hypothalamic cell proliferation by ciliary neurotrophic factor (CNTF). It appears that new cells are born throughout the hypothalamic parenchyma without an apparent restriction to a specific neurogenic layer, as seen in the SVZ. Thus, we provide evidence that the adult hypothalamus is constitutively neurogenic and that hypothalamic cell proliferation is highly responsive to mitogen action. J. Comp. Neurol. 505:209–220, 2007. © 2007 Wiley‐Liss, Inc.
Discrete sine transform and its inverse—realization through recursive algorithms
Authors: Jain Priyanka , Kumar Balbir , Jain Shail Bala
Published: September 2007

In this paper, the implementation of the discrete sine transform (DST) and its inverse (IDST) are developed. General length structure of the DST and IDST, which can be implemented by using the recursive structures, has been proposed. Necessary formulas required for the recursive structures have been derived using mathematical manipulations. Copyright © 2007 John Wiley & Sons, Ltd.
Automated analysis of neurite branching in cultured cortical neurons using HCA‐Vision
Authors: Vallotton Pascal , Lagerstrom Ryan , Sun Changming , Buckley Michael , Wang Dadong , De Silva Melanie , Tan Seong‐Seng , Gunnersen Jenny M.
Published: September 2007

Manual neuron tracing is a very labor‐intensive task. In the drug screening context, the sheer number of images to process means that this approach is unrealistic. Moreover, the lack of reproducibility, objectivity, and auditing capability of manual tracing is limiting even in the context of smaller studies. We have developed fast, sensitive, and reliable algorithms for the purpose of detecting and analyzing neurites in cell cultures, and we have integrated them in software called HCA‐Vision, suitable for the research environment. We validate the software on images of cortical neurons by comparing results obtained using HCA‐Vision with those obtained using an established semi‐automated tracing solution (NeuronJ). The effect of the Sez‐6 deletion was characterized in detail. Sez‐6 null neurons exhibited a significant increase in neurite branching, although the neurite field area was unchanged due to a reduction in mean branch length. HCA‐Vision delivered considerable speed benefits and reliable traces. © 2007 International Society for Analytical Cytology.
Analytical modelling and evaluation of generalized processor sharing systems with heterogeneous traffic
Authors: Jin Xiaolong , Min Geyong
Published: September 2007

Generalized processor sharing (GPS) has been widely studied as an important scheme for providing differentiated quality of service. Realistic traffic in multi‐service networks exhibits heterogeneous properties and can be categorized into two classes, namely, long range dependent (LRD) and short range dependent (SRD) traffic. Performance modelling and analysis of GPS systems subject to heterogeneous network traffic is an open and challenging problem. This paper develops an analytical performance model for GPS systems under heterogeneous LRD and SRD traffic. To this end, we propose a cost‐efficient modelling method for GPS and further develop the analytical upper and lower bounds of the queue length distributions for individual traffic flows. Numerical examples and extensive simulation results are presented to validate the accuracy and merits of the analytical model. Copyright © 2007 John Wiley & Sons, Ltd.
A transgenic mouse Class‐III β tubulin reporter using yellow fluorescent protein
Authors: Liu Li , Geisert Eldon E. , Frankfurter Anthony , Spano Anthony J. , Jiang Chloe Xue , Yue Junming , Dragatsis Ioannis , Goldowitz Dan
Published: September 2007

A yellow fluorescence protein (YFP) reporter construct was cloned downstream of the β‐tubulin III promoter and injected to produce two founder lines of transgenic mice. YFP expression was observed in many regions of the developing peripheral and central nervous system. YFP expression was first observed in the peripheral and central nervous system as early as embryonic day 9.0. There was a dramatic increase in the number of neuronal systems expressing YFP through P0. Then as the animals reached adult age, the expression levels decreased, but many neurons still show YFP expression, notably in regions of the brain undergoing adult neurogenesis, i.e., the rostral migratory stream and subgranular layer of the dentate gyrus. This reporter‐based staining was compared with anti‐class‐III β‐tubulin immunocytochemistry and shown to closely parallel the expression of the endogenous protein. These transgenic lines should provide unique models to study in vivo and in vitro neurodevelopment. genesis 45:560–569, 2007. © 2007 Wiley‐Liss, Inc.
IL‐33 is a chemoattractant for human Th2 cells
Authors: Komai‐Koma Mousa , Xu Damo , Li Yubin , McKenzie Andrew N. J. , McInnes Iain B. , Liew Foo Y.
Published: September 2007

IL‐33 is a novel cytokine of the IL‐1 family and mediates its biological effect via the receptor ST2, which is selectively expressed on Th2 cells but not Th1 cells. IL‐33 drives production of Th2‐associated cytokines including IL‐5 and IL‐13 and thereby promotes defense and pathology in mucosal organs. Cell locomotion is crucial to the induction of an effective immune response. We report here the chemoattraction of Th2 cells by IL‐33. Recombinant IL‐33 increased the proportion of human Th2 cells, but not Th1 cells, in polarized morphology in vitro and stimulated their subsequent invasion into collagen gels in an IL‐33 concentration‐dependent manner. Injection of recombinant IL‐33 into the footpad of ST2–/– mice which had been adoptively transferred with polarized Th2 cells, led to local accumulation of the transferred Th2 cells. These data therefore demonstrate that IL‐33 is a selective Th2 chemoattractant associated with the pro‐inflammatory property of this novel cytokine.
Stepwise Assembly of Nanoparticles, ‐tubes, ‐rods, and ‐wires in Reverse Micelle Systems
Authors: Chen Yun , Wu Qingsheng , Ding Yaping
Published: September 2007

A traditional facile method was used for the stepwise‐assembly synthesis of CaSO4·2H2O nanoparticles, ‐tubes, ‐rods, and ‐wires. Sizes of these nanostructures vary from tens of nanometers to tens of microns. The key point of the stepwise‐assembly process is the reaction time. The growth process was studied as a function of the reaction time and this was used to guide the synthesis of other one‐dimensional nanomaterials in reverse micelle systems. The results showed that this growth process is somewhat universal in synthesizing inorganic salts with zero/one‐dimensional and solid/hollow structures in reverse micelle systems. The growing mechanism was also explored and it was believed to be an assembly‐based growth in association and concurrent with the surfactant‐templating mechanism. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
VIVO Complexes of Bis(imidazol‐2‐yl) Derivatives: A Potentiometric, Spectroscopic and DFT Study
Authors: Várnagy Katalin , Csorba Timea , Kiss Dóra , Garribba Eugenio , Micera Giovanni , Sanna Daniele
Published: September 2007

The complexation of the VIVO ion with four amino acid derivatives of bis(imidazol‐2‐yl)methylamine [N‐glycyl‐bis(imidazol‐2‐yl)methylamine = Gly‐BIMA, N‐α‐aspartyl‐bis(imidazol‐2‐yl)methylamine = α‐Asp‐BIMA, N‐α‐glutamyl‐bis(imidazol‐2‐yl)methylamine = α‐Glu‐BIMA and N‐histidyl‐bis(imidazol‐2‐yl)methylamine = His‐BIMA] was studied in aqueous solution through the combined application of potentiometric and spectroscopic (UV/Vis and EPR) techniques. For comparison, the complexing capability of three simple bis(imidazol‐2‐yl) derivatives [bis(imidazol‐2‐yl)methane = BIM, bis(imidazol‐2‐yl)methylamine = BIMA and bis(imidazol‐2‐yl)nitromethane = BINM] and two benzyloxycarbonyl (Z) derivatives (Z‐Gly‐BIMA and Z‐Ala‐BIMA) was reported. Mono‐ and bis‐chelated species with the (Nim, Nim) donor set were formed in both acid and neutral pH conditions, with the bis‐chelated complexes being characterised by a cis‐trans isomerism. In the basic pH range the complexation process continues with the formation of a mono‐hydroxo cis‐VOL2H–1 complex in systems with BIM, BIMA and BINM, and with the deprotonation and coordination of the amide nitrogen to give VOLH–1 and VOLH–2 in those with Gly‐BIMA, α‐Asp‐BIMA, α‐Glu‐BIMA and His‐BIMA. The results demonstrate that the bis(imidazol‐2‐yl)methyl residue is an anchoring group of intermediate strength, capable of avoiding extensive hydrolysis of the VIVO ion in the presence of a slight excess of ligand (L/M from 3:1 to 5:1). DFT calculations with progressively more complex basis sets were performed in order to obtain information on the structure of the VOLH–1 and VOLH–2 complexes. Finally, a discussion on the 51V anisotropic parallel hyperfine coupling constant (A∥) of VOLH–1 and VOLH–2 and on the EPR properties connected to the V–N–(amide) bond in VIVO complexes is presented. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
The First Example of a Bis(trifluoromethyl)carbene Transition‐Metal Complex and Its Reduction to a Perfluoroallene Complex
Authors: Yuan Jian , Hughes Russell P. , Rheingold Arnold L.
Published: September 2007

Na/Pb alloy reduction of the (perfluoroisopropyl)iridium complex Cp*(CO)IrI[CF(CF3)2] afforded the first example of a bis(trifluoromethyl)carbene complex, Cp*(CO)Ir=C(CF3)2, which has been crystallographically characterized. Further reduction of this carbene complex with KC8 yielded the perfluoroallene iridium complex Cp*Ir(CO)(η2‐CF2CCF2). (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Simple and Feasible Simultaneous Determination of Three Phenolic Pollutants on Boron‐Doped Diamond Film Electrode
Authors: Lei Yanzhu , Zhao Guohua , Liu Meichuan , Xiao Xiaoe , Tang Yiting , Li Dongming
Published: September 2007

A simple, rapid and feasible method is developed for direct and simultaneous determination of phenol (Ph), hydroquinone (HQ) and 4‐nitrophenol (4‐NP) on unmodified boron‐doped diamond (BDD) electrode. Results showed that the oxidative peaks of these three phenolic compounds can be completely separated on BDD electrode in acidic conditions by using electrochemical cyclic voltammetry technique. The peak potential separations are all higher than 0.35 V. Moreover, BDD electrode is extremely easy to be refreshed to obtain current values with good reproducibility, even if it is passivated by phenolic compounds with different adsorption characteristics. All the above features are on account of the outstanding electrochemical characteristics of BDD electrode, and lead to the advantage and feasibility for simultaneous determination of three phenolic compounds without any other separation operation. For each tested phenolic compound, the concentration range with linearity is in two or three orders of magnitude in the presence of other coexisting phenolic compounds with the concentrations more than 1000 times higher than that of the tested component. The present method is also shown to be promising for the determination of phenolic contaminants in the real wastewater samples.
Effect of Various Deposition Techniques, Electrode Materials and Posttreatment with Tetrabutylammonium and Tetrabutylphosphonium Salts on the Electrochemical Behavior and Stability of Various Prussian Blue Modified Electrodes
Authors: Haghighi Behzad , Shams Nafiseh , Gorton Lo
Published: September 2007

The effect of various deposition techniques, electrode materials and posttreatment with tetrabutylammonium and tetrabutylphosphonium salts on the electrochemical behavior and stability of various Prussian blue (PB) modified electrodes, namely PB modified glassy carbon electrodes, silicate‐film supported PB modified glassy carbon electrodes, PB‐doped silicate glassy carbon electrodes, PB modified carbon ceramic electrodes using electrochemical deposition and PB modified carbon ceramic electrodes using chemical deposition is reported. Cyclic voltammetry and amperometric measurements of hydrogen peroxide were performed in a flow injection system while the carrier phosphate buffer (pH 7.0) with a flow rate of 0.8 mL min−1 was propelled into the electrochemical flow through cell housing the PB modified working electrode as well as an Ag|AgCl|0.1 M KCl reference and a Pt auxiliary electrode. The results showed that the deposition procedure, electrode material and posttreatment with additional chemicals can significantly alter the stability and electrochemical behavior of the PB film. Among the studied PB modified electrodes, those based on carbon ceramic electrodes modified with a film of electropolymerized PB showed the best electrochemical stability.
Zinc Oxide/Zinc Hexacyanoferrate Hybrid Film‐Modified Electrodes for Guanine Detection
Authors: Chu Hung‐Wei , Thangamuthu R. , Chen Shen‐Ming
Published: September 2007

An electroactive polynuclear hybrid films of zinc oxide and zinc hexacyanoferrate (ZnO/ZnHCF) have been deposited on electrode surfaces from H2SO4 solution containing Zn(NO3)2 and K3[Fe(CN)6] by repetitive potential cycling method. Simultaneous cyclic voltammetry and electrochemical quartz crystal microbalance (EQCM) measurements demonstrate the steady growth of hybrid film. There are two redox couples present in the voltammograms of hybrid film and it is obvious in the case of pH 2. Surface morphology of hybrid film was investigated using scanning electron microscopy (SEM) and atomic force microscopy (AFM). Energy dispersive spectrometer (EDS) data confirm existence of zinc oxide in the hybrid film. The effect of type of monovalent cations on the redox behavior of resulting film was investigated. In pure supporting electrolyte, electrochemical responses of modified electrode resemble with that of a surface immobilized redox couple. The electrocatalytic activity of ZnO/ZnHCF hybrid film was investigated towards guanine using cyclic voltammetry and rotating disc electrode (RDE) techniques. Finally, feasibility of using ZnO/ZnHCF hybrid film‐coated electrodes for guanine estimation in flow injection analysis (FIA) was also investigated.
Novel staining‐free proteomic method for simultaneous identification of proteins and determination of their pI values by using low‐molecular‐mass pI markers
Authors: Chmelík Josef , Mazanec Karel , Šlais Karel
Published: September 2007

A new proteomic staining‐free method for simultaneous identification of proteins and determination of their pI values by using low‐molecular‐mass pI markers is described. It is based on separation of proteins in gels by IEF in combination with mass spectrometric analysis of both peptides derived by in‐gel digestion and low‐molecular‐mass pI markers extracted form the same piece excised from the gel. In this method, the pI markers are mixed with a protein mixture (a commercial malted barley protein extract) deposited on a gel and separated in a pH gradient. Color pI markers enable supervision of progress of focusing process. Several separated bands of the pI markers (including separated proteins) were excised and the pI markers were eluted from each gel piece by water/ethanol and identified by MALDI‐TOF/TOF MS. The remaining carrier ampholytes were then washed out from gel pieces and proteins were in‐gel digested with trypsin or chymotrypsin. Obtained peptides were measured by MALDI‐TOF/TOF MS and proteins were identified via protein database search. This procedure allows omitting time‐consuming protein staining and destaining procedures, which shortens the analysis time. For comparison, other IEF gels were stained with CBB R 250 and proteins in the gel bands were identified. Similarity of the results confirmed that our approach can give information about the correct pI values of particular proteins in complex samples at significantly shorter analysis times. This method can be very useful for identification of proteins and their post‐translational modifications in prefractioned samples, where post‐translational modifications (e.g., glycation) are frequent.
Lights, Camera, Action! Systematic variation in 2‐D difference gel electrophoresis images
Authors: Sellers Kimberly F. , Miecznikowski Jeffrey , Viswanathan Surya , Minden Jonathan S. , Eddy William F.
Published: September 2007

2‐D Difference gel electrophoresis (DIGE) circumvents many of the problems associated with gel comparison via the traditional 2‐DE approach. DIGE's accuracy and precision, however, is compromised by the existence of other significant sources of systematic variation, including that caused by the apparatus used for imaging proteins (location of the camera and lighting units, background material, imperfections within that material, etc.). Through a series of experiments, we estimate some of these factors, and account for their effect on the DIGE experimental data, thus providing improved estimates of the true relative protein intensities. The model presented here includes 2‐DE images as a special case.
Bulk modification of PDMS microchips by an amphiphilic copolymer
Authors: Xiao Yan , Yu Xiao‐Dong , Xu Jing‐Juan , Chen Hong‐Yuan
Published: September 2007

A simple and rapid bulk‐modification method based on adding an amphiphilic copolymer during the fabrication process was employed to modify PDMS microchips. Poly(lactic acid)–poly(ethylene glycol) (PLA–PEG) was used as the additive substance. Compared to the native PDMS microchips, both the contact angle and the EOF of the bulk‐modified PDMS microchips decreased. The effects of the additive loading and the pH on the EOF were investigated in detail. The bulk‐modified PDMS microchips exhibited reproducible and stable EOF behavior. The application of the bulk‐modified PDMS microchips was also studied and the results indicated that they could be successfully used to separate amino acids and to suppress protein adsorption.
Mass distribution, polydispersity, and focusing properties of carrier ampholytes for IEF. Part V: pH 9–11 interval
Authors: Simó Carolina , Citterio Attilio , Righetti Pier Giorgio
Published: September 2007

As a last part of an investigation on all 2‐pH‐unit intervals of carrier ampholytes (CAs) for IEF (see Electrophoresis 2006, 27, 3919–3934; 2006, 27, 4849–4858; 2007, 28, 715–723) two different lots of Servalyt CAs, in the pH 9–11 range, have been analyzed by a 2‐D technique based on preparative Rotofor fractionation followed by capillary electrophoresis mass‐spectrometry of 10 out of 20 fractions harvested, in the second dimension. The findings: the two lots contain 65 and 69 different Mr compounds, in the Mr interval of 232–667 Da, for a total of 341–387 isoforms, respectively. Since this is a chaotic organic synthesis, the high reproducibility (here demonstrated for the first time during the 40 years of existence of CAs) of the synthetic process (for two batches produced at 6 years of distance) is remarkable, considering that a 94% agreement for the individual chemicals and 88% agreement for the total number of isoforms for the two lots is found. It is additionally demonstrated that the lower pI species are accompanied by considerably more isoforms than the high pI forms and that in all cases such isoforms consist of family of compounds clustered around the pI of the parental form, with a pI spread of ca. 0.1–0.2 pH units.
An investigation of peak‐broadening effects arising when combining CE with MS
Authors: Axén Jakob , Axelsson Bengt‐Olof , Jörntén‐Karlsson Magnus , Petersson Patrik , Sjöberg Per J. R.
Published: September 2007

In this study, peak‐broadening effects caused by nebulizing gas flow and lack of temperature control have been investigated for separation capillaries with three different inner diameters. The study was performed with serial UV/ESI‐MS detection in an effort to distinguish between peak broadening arising in the separation and peak broadening arising in the ion source. The nebulizing gas was found to significantly affect both migration time and separation efficiency when using capillaries with 50 and 75 µm id. If the nebulizing gas is on during injection, the injection volume increases to such an extent that significant peak broadening is induced. Reducing the id to 25 µm minimizes the parabolic flow induced by the nebulizing gas. Results indicate that the nebulizing gas pressure can be optimized to minimize peak broadening in the ion source. A decrease in detection sensitivity, possibly related to the orthogonal design of the interface, was observed when the nebulizing gas pressure was increased. A tapered capillary tip was found to provide superior separation efficiency as well as sensitivity.
INAR(1) modeling of overdispersed count series with an environmental application
Authors: Pavlopoulos Harry , Karlis Dimitris
Published: September 2007

This paper is concerned with a novel version of the INAR(1) model, a non‐linear auto‐regressive Markov chain on ℕ, with innovations following a finite mixture distribution of $m \geq 1$ Poisson laws. For $m > 1$, the stationary marginal probability distribution of the chain is overdispersed relative to a Poisson, thus making INAR(1) suitable for modeling time series of counts with arbitrary overdispersion. The one‐step transition probability function of the chain is also a finite mixture, of m Poisson‐Binomial laws, facilitating likelihood‐based inference for model parameters. An explicit EM‐algorithm is devised for inference by maximization of a conditional likelihood. Alternative options for inference are discussed along with criteria for selecting m. Integer‐valued prediction (IP) is developed by a parametric bootstrap approach to ‘coherent’ forecasting, and a certain test statistic based on predictions is introduced for assessing performance of the fitted model. The proposed model is fitted to time series of counts of pixels where spatially averaged rain rate exceeds a given threshold level, illustrating its capabilities in challenging cases of highly overdispersed count data. Copyright © 2007 John Wiley & Sons, Ltd.
Empirical significance values for linkage analysis: trait simulation using posterior model distributions from MCMC oligogenic segregation analysis
Authors: Igo Robert P. , Wijsman Ellen M.
Published: September 2007

Variance‐components (VC) linkage analysis is a powerful model‐free method for assessing linkage, but the distribution of VC logarithm of the odds ratio (LOD) scores may deviate substantially from the assumed asymptotic distribution. Typically, the null distribution of the VC‐LOD score and other linkage statistics has been estimated by generating new genotype data independently of the trait data, and computing a linkage statistic for many such marker‐simulated data sets. However, marker simulation is susceptible to errors in the assumed marker and map model and is computationally intensive. Here, we describe a method for generating posterior distributions of linkage statistics through simulation of trait data based on the original sample and on results from an initial scan using a Bayesian Markov‐chain Monte Carlo (MCMC) approach for oligogenic segregation analysis. We use samples of oligogenic trait models taken from the posterior distribution to generate new samples of trait data, which were paired with the original marker data for analysis. Empirical P‐values obtained from trait and marker simulation were similar when derived for several strong linkage signals from published linkage scans, and for analysis of data with a known, simulated, trait model. Furthermore, trait simulation produces the expected null distribution of VC‐LOD scores and is computationally fast when marker identity‐by‐descent estimates from the original data could be reused. These results suggest that trait simulation gives valid estimates of statistical significance of linkage signals. Finally, these results also demonstrate the feasibility of obtaining empirical significance levels for evaluating Bayesian oligogenic linkage signals with either marker or trait simulation. Genet. Epidemiol. 2008. © 2007 Wiley–Liss, Inc.
Reaction of a cyclic triphosphenium ion with triflic acid and SnX2 (X = Br or Cl): A 31P NMR study
Authors: Boyall Alice J. , Dillon Keith B. , Monks Philippa K. , Potts Jennifer C.
Published: September 2007

The di‐ium dication formed by triflic acid protonation of the cyclic triphosphenium ion derived from 1,4‐bis‐diphenylphosphinobutane, (dppb), and P3(X = Br or Cl) decomposes via an acyclic dication bearing a PHX group; this intermediate is reduced by SnX2 in the presence of HX to yield a dication with a PH2 primary phosphane terminal group, which is comparatively stable. The structure of this species has been unequivocally confirmed by 31P solution‐state NMR spectroscopy. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:609–612, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20302
Lithium bis(2‐phenylphosphidoethyl)phenyl‐phosphine: A reactive phosphorus intermediate
Authors: Mason Lucas J. , Moore Alexander J. , Carr Amy , Helm Monte L.
Published: September 2007

Bis(2‐phenylphosphinoethyl)phenylphosphine, PhP(CH2CH2PPh2)2, reacts with lithium in tetrahydrofuran to give the corresponding lithium bis(2‐diphenylphosphidoethyl)phenylphosphine, Li2[PhP(CH2CH2PPh)2]. The lithium diphosphide is identified by NMR spectroscopy and further characterized through arylation with excess brombenzene to reform the starting phosphine, PhP(CH2CH2PPh2)2. Initial reactivity studies of the diphosphide, PhP(CH2CH2PPh), with some alkylhalides are also described. © 2007 Wiley Periodicals, Inc. Heteroatom Chem 18:675–678, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20351
Inhibition of mRNA synthesis in the hippocampus impairs consolidation and reconsolidation of spatial memory
Authors: Da Silva Weber C. , Bonini Juliana S. , Bevilaqua Lia R.M. , Medina Jorge H. , Izquierdo Iván , Cammarota Martín
Published: September 2007

Using two different mRNA synthesis inhibitors, we show that blockade of hippocampal gene expression during restricted posttraining or postretrieval time windows hinders retention of long‐term spatial memory for the Morris water maze task, without affecting short‐term memory, nonspatial learning, or the functionality of the hippocampus. Our results indicate that spatial memory consolidation induces the activation of the hippocampal transcriptional machinery and suggest the existence of a gene expression‐dependent reconsolidation process that operates in the dorsal hippocampus at the moment of retrieval to stabilize the reactivated mnemonic trace. © 2007 Wiley‐Liss, Inc.
GSK3 promotes arsenite‐induced apoptosis via facilitation of mitochondria disruption
Authors: Watcharasit Piyajit , Thiantanawat Apinya , Satayavivad Jutamaad
Published: September 2007

Arsenic is an environmental toxicant that recently has been shown to have anticancer activity against a number of types of cancer cells by inducing apoptosis. Glycogen synthase kinase‐3 (GSK3), a serine/threonine kinase, is an important pro‐apoptotic signaling enzyme. Although GSK3 has been shown to promote apoptosis caused by a wide variety of insults, a role for GSK3 in arsenic‐induced apoptosis has not yet been identified. Investigation of the involvement of GSK3 in arsenite‐induced apoptosis demonstrated that arsenite induced apoptosis in SH‐SY5Y human neuroblastoma cells, activating the executioner caspase‐3 which caused cleavage of poly‐ADP ribose‐polymerase (PARP). Two selective GSK3 inhibitors, lithium and SB216763, attenuated caspase‐3 activation and PARP cleavage induced by arsenite treatment indicating that GSK3 contributed to arsenite‐induced apoptosis. Apoptotic signaling following exposure to arsenite involved cytochrome C release from mitochondria, and this was reduced by inhibition of GSK3 indicating that GSK3 promotes arsenite‐induced apoptotic signaling upstream of mitochondrial disruption. Moreover, arsenite induced the translocation of Bax and p53 to the mitochondria and the activation‐associated oligomerization of Bax, and these crucial events were reduced by inhibition of GSK3, indicating that GSK3 promotes arsenite‐induced apoptosis by facilitating signals leading to mitochondrial apoptotic events. Taken together, the findings from this study reveal that GSK3 promotes arsenite‐induced apoptosis by facilitating signaling leading to disruption of mitochondria. Copyright © 2007 John Wiley & Sons, Ltd.
Effects of irradiance, wavelength, and thermal emission of different light curing units on the Knoop and Vickers hardness of a composite resin
Authors: Torno Vladja , Soares Paulo , Martin Juliana M. H. , Mazur Rui F. , Souza Evelise M. , Vieira Sérgio
Published: September 2007

The aim of this study was to evaluate the effects of irradiance, light emission wavelength, and heating of different light curing units on the Knoop and Vickers hardness of a hybrid composite resin. The specimens were irradiated during 40 s with ten different light curing units, LEDs, and halogen lights. The spectral emission of each light curing unit was assessed by a spectrometer, the irradiance was measured by two commercial radiometers, and the heating measured with a thermocouple. After 48 h of storage in a dark recipient under a 100% humidity condition, the Knoop and Vickers hardness tests were carried out. The hardness results were analyzed by ANOVA, and Tukey HSD test (p < 0.05). The results showed that the surface hardness of the composite resin depends not only on the irradiance, but strongly on the emission wavelength and heating of the light curing units. It was observed, a linear correlation between the conversion degree and radiant exposure. In addition, it is suggested that the well known base to top surface hardness ratio convention of 80–90% is not appropriate to evaluate curing efficiency of composites, since the top surface is not always sufficiently polymerized. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Structural changes of UHMWPE after e‐beam irradiation and thermal treatment
Authors: Slouf Miroslav , Synkova Hana , Baldrian Josef , Marek Antonin , Kovarova Jana , Schmidt Pavel , Dorschner Helmut , Stephan Michael , Gohs Uwe
Published: September 2007

Ultra‐high molecular weight polyethylene (UHMWPE) was irradiated with accelerated electrons (1 MeV in air) using high dose rates (> 25 kGy/min) and thin specimens (thickness 1 mm). Parts of the specimens were remelted (200°C for 10 min; 150°C for 0, 2, 10, 30, 60 min). All specimens were stored in nitrogen in the dark at 5°C. Supermolecular structure, extent of crosslinking, oxidative degradation, and macroradical content were studied by a number of methods (SAXS, WAXS, SEM, DSC, FTIR, ESR, TGA, solubility experiments, image analysis). The results obtained with irradiated samples were compared with those obtained with irradiated and remelted samples. It was confirmed that crosslinking predominates over chain scission at very high dose rates, even if the irradiation is performed in air. Discrepancies concerning supermolecular structure changes in UHMWPE after irradiation and thermal treatment, found in various studies in the literature, are discussed. A simple model, which describes and explains all supermolecular structure changes, is introduced. An effective way of eliminating residual macroradicals in UHMWPE is proposed. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2008
Lipase‐catalyzed synthesis of butyl esters by direct esterification in solvent‐free system
Authors: Santos Júlio C , Bueno Tânia , Molgero Patrícia C , Rós Da , de Castro Heizir F
Published: September 2007

BACKGROUND:

Reactions performed under solvent‐free conditions give processes that are environmentally friendly, since most solvents are polluting agents. In this work, the performance of Candida rugosa lipae (CRL) immobilized on styrene‐divinylbenzene (STY‐DVB) or controlled pore silica (CPS), and the commercial lipase Novozym 435, was evaluated for the synthesis of butyl esters in solvent–free systems (SFS). A 22 full factorial design was used to study the influence of the organic acid chain length and the biocatalyst concentration on the esterification performance.

RESULTS:

When CRL on STY‐DVB was used, the ester formation was influenced by both variables and their interaction. The reaction conversion was higher (63%) using 10% of immobilized system and lauric acid, corresponding to a productivity of 3.62 g L−1 h−1 For CRL on CPS, only the effect of biocatalyst concentration was significant, and the highest yield was attained using 20% of immobilized system and caprilic acid. In the case of Novozym 435, the highest yield (49%) was obtained using butyric acid as acyl donor at 15% of immobilized lipase.

CONCLUSION:

The results allowed better understanding of the influence of important parameters in this environmentally friendly process, which also has the process advantage of a higher volumetric productivity when compared with a solvent system. Copyright © 2007 Society of Chemical Industry
Chondrocytes interconnecting tracks and cytoplasmic projections observed within the superficial zone of normal human articular cartilage—A transmission electron microscopy, atomic force microscopy, and two‐photon excitation microscopy studies
Authors: González Sirenia , Fragoso‐Soriano Rogelio J. , Kouri Juan B.
Published: September 2007

The morphology of the normal human and rat articular cartilage was assessed using transmission electron microscopy (TEM), atomic force microscopy (AFM), and two‐photon excitation (2PE) microscopy. Spurr‐embedded sections from fixed human cartilage were simultaneously evaluated using TEM and AFM. The presences of tracks among the chondrocytes from the superficial zone of the cartilage were observed. In order to ratify the presence of interconnecting tracks among superficial zone chondrocytes, whole fixed human and rat cartilage, as well as fresh whole rat cartilage, were examined under the 2PE. In all cases, these tracks were observed. In addition, porous matrix, well‐defined lacunae, and cytoplasmic projections anchored to the extracellular matrix (ECM) were also detected. We conclude that normal human and rat flattened superficial chondrocytes might be interconnected by tracks running through the ECM. In addition, cytoplasmic projections were observed anchored to the ECM. All these structures may possibly be related to cell/cell and ECM/chondrocytes signaling. Our findings provide new information that possibly will be of relevant importance for a more profound study of normal cartilage physiology and eventually, the pathogenesis of osteoarthritis. Microsc. Res. Tech., 2007. © 2007 Wiley‐Liss, Inc.
Comparison of reflection contrast microscopy and electron microscopy on the histopathological diagnosis of various kidney diseases
Authors: Yuruker S. , Zeybek D. , Asan E.
Published: September 2007

Our aim in this study was to compare reflection contrast microscopy (RCM) with transmission electron microscopy (TEM) to understand whether RCM could be used in the histopathological diagnosis of various kidney diseases as a less expensive and an easier alternative to TEM. The diagnoses of kidney pathologic lesions included Alport syndrome, thin membrane disease, Ig A nephropathy. RCM is a form of light microscope that works in the reflected mode, suitable to observe ultrathin (50–100 nm) plastic sections that is also used in TEM. Our findings showed that RCM showed similar results compared with TEM on these lesions described earlier. Microsc. Res. Tech., 2008. © 2007 Wiley‐Liss, Inc.
Optical disector counting in cryosections and vibratome sections underestimates particle numbers: Effects of tissue quality
Authors: Ward Tyson S. , Rosen Glenn D. , von Bartheld Christopher S.
Published: September 2007

Optical disector counting is currently applied most often to cryosections, followed in frequency by resin‐embedded tissues, paraffin, and vibratome sections. The preservation quality of these embedding options differs considerably; yet, the effect of tissue morphology on numerical estimates is unknown. We tested whether different embedding media significantly influence numerical estimates in optical disector counting, using the previously calibrated trochlear motor nucleus of hatchling chickens. Animals were perfusion‐fixed with paraformaldehyde (PFA) only or in addition with glutaraldehyde (GA), or by Methacarn immersion fixation. Brains were prepared for paraffin, cryo‐, vibratome‐ or celloidin sectioning. Complete penetration of the thionin stain was verified byz‐axis analysis. Neuronal nuclei were counted using an unbiased counting rule, numbers were averaged for each group and compared by ANOVA. In paraffin sections, 906 ± 12 (SEM) neurons were counted, similar to previous calibrated data series, and results obtained from fixation with Methacarn or PFA were statistically indistinguishable. In celloidin sections, 912 ± 28 neurons were counted—not statistically different from paraffin. In cryosections, 812 ± 12 neurons were counted (underestimate of 10.4%) when fixed with PFA only, but 867 ± 17 neurons were counted when fixed with PFA and GA. Vibratome sections had the most serious aberration with 729 ± 31 neurons—a deficit of 20%. Thus, our analysis shows that PFA‐fixed cryosections and vibratome sections result in a substantial numerical deficit. The addition of GA to the PFA fixative significantly improved counts in cryosections. These results may explain, in part, the significant numerical differences reported from different labs and should help investigators select optimal conditions for quantitative morphological studies. Microsc. Res. Tech., 2008. © 2007 Wiley‐Liss, Inc.