bluuebunny/crossref_metadata_2025 huggingface dataset:
Assessment of Ion‐Ionophore Complex Diffusion Coefficients in Solvent Polymeric Membranes
Authors: Zook Justin M. , Bodor Sándor , Lindner Ernő , Tóth Klára , Gyurcsányi Róbert E.
Published: September 2009

Chronoamperometric (CA) and chronopotentiometric (CP) transients have been used previously for the determination of the diffusion coefficients of free ionophores in ion‐selective liquid membranes. In this work, the CA and CP transients are utilized to determine the diffusion coefficients of a variety of ion‐ionophore complexes in these membranes. The conditions under which the ion‐ionophore complex diffusion coefficients can be determined from the CA and CP transients are discussed. For most ionophores, the ion‐ionophore complex diffusion coefficients were found to be slightly smaller or similar to the previously calculated free ionophore diffusion coefficients. However, for a couple of ionophores, the ion‐ionophore complex diffusion coefficients were found to be significantly smaller than expected. Significant ion‐pair formation in the membranes can explain this disparity.
Quantification of economic, environmental and operational benefits due to significant penetration of Microgrids in a typical LV and MV Greek network
Authors: Hatziargyriou N. D. , Anastasiadis A. G. , Tsikalakis A. G. , Vasiljevska J.
Published: September 2009

The effect of the use of a Microgrid Central Controller (MGCC) to achieve co‐ordinated operation of various DG sources, storage devices and controllable loads with regards to the potential economic benefits and the power losses avoided in the local network is presented. Additionally, the effect of connecting numerous typical Microgrids in a typical medium voltage (MV) network regarding power losses and the emissions avoided is studied. The emissions avoidance calculation is based on the marginal emissions curve of the upstream network, quantifying also the calculated losses reduction impact on emissions avoidance. The presented results, based on a variety of realistic market prices time‐series, various levels of renewable energy resource (RES) production and demand from different seasons, show clear benefits in terms of both losses and emissions avoidance. Finally, this paper performs a sensitivity analysis on the potential impact of the DG topology within a Microgrid on losses and emissions avoidance. Copyright © 2009 John Wiley & Sons, Ltd.
Control Loop Design and Control Performance Study on Direct Internal Reforming Solid Oxide Fuel Cell
Authors: Zhang H. , Weng S. , Su M.
Published: September 2009

A solid oxide fuel cell (SOFC) stack is a complicated nonlinear power system. Its system model includes a set of partial differential equations that describe species, mass, momentum and energy conservation, as well as the electrochemical reaction models. The validation and verification of the control system by experiment is very expensive and difficult. Based on the distributed and lumped model of a one‐dimensional SOFC, the dynamic performance with different control loops for SOFC is investigated. The simulation result proves that the control system is appropriate and feasible, and can effectively satisfy the requirement of variable load power demand. This simulation model not only can prevent some latent dangers of the fuel cell system but also predict the distributed parameters' characteristics inside the SOFC system.
Moving Forward in Central Asia
Authors: Bienert Hans‐Dieter
Published: September 2009

How science in Kazakhstan and Uzbekistan is looking to make international connections
Trust and Responsibility
Authors: Kleiner Matthias
Published: September 2009

Meeting expectations after the go‐ahead for the Excellence Initiative, the Joint Initiative for Research and Innovation and the Higher Education Pact
Detecting Sugar in Baby Food
Authors: Hummel Sandra , Pflüger Maren , Ziegler Anette‐G.
Published: September 2009

When babies contract type 1 diabetes, could it be caused by their food? A large‐scale study looks at the role of gluten as a catalyst
Welcome to Tokyo!
Authors: Streier Eva‐Maria
Published: September 2009

Boost for scientific cooperation with the Far East: DFG opens office in Japanese capital
An information and communication technologies–based framework for enhancing project management education through competence assessment and development
Authors: Makatsoris Charalampos
Published: September 2009

Advances in information and communication technologies (ICT) have had a great impact on ways of working and communicating across all industrial sectors, including education. However, the education sector has been lacking adoption of potentially key technologies that can help improve delivery of modules and the overall learning experience of students. This research aims at addressing the important problem of understanding the strengths, weaknesses, current competences, and existing soft skills of new Masters of Science students starting a course on Project Management. This information is important for instructors as they can adapt and optimize delivery of such modules, enhance the overall learning experience, and assist the module leader in enhancing content. Also this information is not readily available to module leaders, and these competencies and skills cannot be assessed by traditional academic means. To address this problem a new process is proposed that uses an ICT system called Cycloid as its “backbone.” This article describes a new process and demonstrates it in a practical application. This is done through a study involving a number of students at the School of Engineering and Design at Brunel University who took the course during the 2007–2008 academic year. The aim of the study was to assess and demonstrate the feasibility of the proposed process. Results demonstrate the feasibility of the proposed process for implementation in higher education. © 2009 Wiley Periodicals, Inc.
Baimantuoluosides A – C, Three New Withanolide Glucosides from the Flower of Datura metel L.
Authors: Kuang Haixue , Yang Bingyou , Tang Ling , Xia Yonggang , Dou Deqiang
Published: September 2009

In search for bioactive compounds from the flower of Datura metel L., three new withanolide glucosides, namely baimantuoluosides A, B, and C (1–3, resp.) were isolated. Enzymatic hydrolysis of 1–3 afforded the corresponding aglycones 1a, 2a, and 3a, respectively. The structures of the new compounds were elucidated as (5α,6α,7α,12β,22R)‐5,12‐dihydroxy‐1,26‐dioxo‐6,7 : 22,26‐diepoxyergosta‐2,24‐dien‐27‐yl β‐D‐glucopyranoside (1), (5α,6α,7α,12α,22R)‐5,12‐dihydroxy‐1,26‐dioxo‐6,7 : 22,26‐diepoxyergosta‐2,24‐dien‐27‐yl β‐D‐glucopyranoside (2), (5α,6α,7α,22R)‐5‐hydroxy‐1,26‐dioxo‐6,7 : 22,26‐diepoxyergosta‐2,24‐dien‐27‐yl β‐D‐glucopyranoside (3) on the basis of chemical and physicochemical evidence, and are further confirmed by the structure determination by X‐ray diffraction of withanolide aglycone 1a.
Synthesis of Regioisomeric Functionalized Benzodifurans and Angelicins
Authors: Quezada Elías , Delogu Giovanna , Viña Dolores , Santana Lourdes , Podda Gianni , Joao Matos Maria , Picciau Carmen
Published: September 2009

Arenofurans have important biological and pharmacological activities. Compared to benzofurans, the reports on the synthesis of benzodifurans are rather limited. Here, we report the synthesis of a linear and an angular 3,3′‐bis(carboxymethyl)substituted benzodifuran and 4′‐carboxymethyl‐substituted angelicins from phloroglucinol, using 4‐halomethyl‐substituted dipyrones as key intermediates in the synthetic route. This strategy shows that the stability of a pyrone ring depends on the type of substituent at C(4) and the conditions used.
Diterpenoids from the Hainan Soft Coral Sinularia parva
Authors: Li Yan , Gao An‐Hui , Huang Hui , Li Jia , Mollo Ernesto , Gavagnin Margherita , Cimino Guido , Gu Yu‐Cheng , Guo Yue‐Wei
Published: September 2009

Two new cembrane diterpenes, sinulaparvalides A and B (1 and 2, resp.), which contain an intriguing seven‐membered lactone moiety, along with the four known related cembranoids 3–6, were isolated from the Hainan soft coral Sinularia parva. The structures of compounds 1 and 2 were established by spectroscopic methods, mainly on the basis of 2D‐NMR techniques, and were confirmed by single‐crystal X‐ray diffraction analysis. The in vitro cytotoxic activities of these compounds were tested on human colon carcinoma (HCT‐116), human promyelocytic leukemia (HL‐60), and human lung carcinoma (A‐549) tumor cell lines.
Lingshuine, an Unexpected Passerini Product from the Hainan Sponge Axinyssa variabilis
Authors: Xue Duo‐Qing , Mollo Ernesto , Cimino Guido , Guo Yue‐Wei
Published: September 2009

Lingshuine (1), a novel sesquiterpene amide, along with three known N‐containing compounds, 2–4, have been isolated from the Hainan sponge Axinyssa variabilis. The structure of 1 was elucidated by detailed analysis of the spectroscopic data and by chemical methods. Lingshuine represents the first example of a Passerini product formed during the isolation process.
Two New Withanolides from Physalis peruviana
Authors: Fang Sheng‐Tao , Li Bo , Liu Ji‐Kai
Published: September 2009

Two new perulactone‐type withanolides, named perulactone C (1) and perulactone D (2), together with four known compounds, perulactone (3), perulactone B (4), blumenol A, and (+)‐(S)‐dehydrovomifoliol, were isolated from the aerial parts of Physalis peruviana. The structures of the new compounds were elucidated on the basis of 1D‐ and 2D‐NMR experiments, including HMBC, HSQC, 1H,1H‐COSY, and ROESY, as well as HR‐MS.
Total Synthesis of (+)‐Machaeriols B and C and of Their Enantiomers with a Cannabinoid Structure
Authors: Lee Hee Jin , Lee Yong Rok , Kim Sung Hong
Published: September 2009

An efficient and concise synthesis of the biologically interesting (+)‐machaeriol B (2) and its enantiomer 5 was accomplished from O‐phenylhydroxylamine (7) in four steps (Scheme 2). In addition, the first total synthesis of natural (+)‐machaeriol C (3) and its enantiomer 6 was achieved from the readily available ester 15 in eight steps (Scheme 4). The key strategies in the syntheses of 2 and 5 involved benzofuran formation through a [3,3]‐sigmatropic rearrangement and trans‐hexahydrodibenzopyran formation by a domino aldol‐type/hetero‐Diels–Alder reaction. In the case of 3 and 6, the key steps were stilbene formation by a Horner–Wadsworth–Emmons reaction and trans‐hexahydrodibenzopyran formation by domino reactions.
Synthesis and Anti‐HIV‐1 Evaluation of New Sonogashira‐Modified Emivirine (MKC‐442) Analogues
Authors: Danel Krzysztof , Jørgensen Per T. , Pedersen Erik B. , La Colla Paolo , Collu Gabriella , Loddo Roberta
Published: September 2009

The MKC‐442 analogue 6‐(3,5‐dimethylbenzyl)‐5‐ethyluracil substituted with a (propargyloxo)methyl group at N(1) has previously been found highly active against HIV‐1. The CC bond in the substituent at N(1) is here utilized in a series of chemical reactions in order to develop new agents with higher activity against HIV‐1‐resistant mutants. The syntheses involved Pd‐catalyzed C,C‐coupling reactions, addition of disulfides, and click chemistry on the terminal CC bond as well as addition of bromine to the so formed internal CC bonds. Sonogashira coupling were performed with silyl‐derivatized iodobenzyl alcohols which, after deprotection, were oxidized to aldehydes by means of IBX. The isomeric alcohol 37 was obtained in the Sonogashira reaction of propargyl alcohol with the N(1)‐substituted (4‐iodobenzyloxy)methyl derivative of the above mentioned uracil. Compound 37 turned out to be the most effective compound against problematic HIV‐1 mutants. The general observation in the present work is that a combination of alkyne and aryl in the substituent at N(1) leads to highly active compounds against HIV‐1.
Benzodiazepine Alkaloids from Marine‐Derived Endophytic Fungus Aspergillus ochraceus
Authors: Cui Chuan‐Ming , Li Xiao‐Ming , Li Chun‐Shun , Sun Hao‐Fen , Gao Shu‐Shan , Wang Bin‐Gui
Published: September 2009

A new fungus‐derived benzodiazepine analogue, 2‐hydroxycircumdatin C (1), and a compound which has been isolated from a natural resource for the first time, but has been previously synthesized, namely (11aS)‐2,3‐dihydro‐7‐methoxy‐1H‐pyrrolo[2,1‐c][1,4]benzodiazepine‐5,11(10H,11aH)‐dione (2), along with five structurally related known alkaloids (3–7), were isolated from Aspergillus ochraceus, an endophytic fungus derived from the marine brown alga Sargassum kjellmanianum. Their structures were established on the basis of spectroscopic methods. The absolute configuration of 1 was determined through CD evidence. Compound 1 displayed significant DPPH radical‐scavenging activity with an IC50 value of 9.9 μM, which is 8.9‐fold more potent than that of butylated hydroxytoluene (BHT), a well‐known synthetic positive control.
Runx2‐mediatedbcl‐2gene expression contributes to nitric oxide protection against hydrogen peroxide‐induced osteoblast apoptosis
Authors: Ho Wei‐Pin , Chan Wing‐Pong , Hsieh Ming‐Shium , Chen Ruei‐Ming
Published: September 2009

Nitric oxide (NO) can regulate osteoblast activities. This study was aimed to evaluate the protective effects of pretreatment with sodium nitroprusside (SNP) as a source of NO on hydrogen peroxide‐induced osteoblast insults and its possible mechanisms. Exposure of human osteosarcoma MG63 cells to hydrogen peroxide significantly increased cellular oxidative stress, but decreased ALP activity and cell viability, inducing cell apoptosis. Pretreatment with 0.3 mM SNP significantly lowered hydrogen peroxide‐induced cell insults. Treatment of human MG63 cells with hydrogen peroxide inhibited Bcl‐2 mRNA and protein production, but pretreatment with 0.3 mM SNP significantly ameliorated such inhibition. Sequentially, hydrogen peroxide decreased the mitochondrial membrane potential, but increased the levels of cytochromecand caspase‐3 activity. Pretreatment with 0.3 mM SNP significantly lowered such alterations. Exposure to hydrogen peroxide decreased Runx2 mRNA and protein syntheses. However, pretreatment with 0.3 mM SNP significantly lowered the suppressive effects. Runx2 knockdown using RNA interference inhibited Bcl‐2 mRNA production in human MG63 cells. Protection of pretreatment with 0.3 mM SNP against hydrogen peroxide‐induced alterations in ALP activity, caspase‐3 activity, apoptotic cells, and cell viability were also alleviated after administration of Runx2 small interference RNA. Thus, this study shows that pretreatment with 0.3 mM SNP can protect human MG63 cells from hydrogen peroxide‐induced apoptotic insults possibly via Runx2‐involved regulation ofbcl‐2gene expression. J. Cell. Biochem. 108: 1084–1093, 2009. © 2009 Wiley‐Liss, Inc.
Physiological and coordinate downregulation of the NPC1 and NPC2 genes are associated with the sequestration of LDL‐derived cholesterol within endocytic compartments
Authors: Jelinek David , Patrick Sarah Mount , Kitt Khameeka N. , Chan Teddy , Francis Gordon A. , Garver William S.
Published: September 2009

The Niemann‐Pick C1 and C2 (NPC1 and NPC2) proteins have a central role in regulating the transport of lipoprotein‐derived cholesterol from endocytic compartments to the endoplasmic reticulum for esterification by acyl‐CoA:cholesterol acyltransferase (ACAT) and feedback inhibition of the sterol regulatory element‐binding protein (SREBP) pathway. Since the NPC1 gene/protein has recently been shown to be downregulated by feedback inhibition of the SREBP pathway, the present study was performed to determine whether physiological downregulation of the NPC1 gene/protein alters the transport and metabolism of low‐density lipoprotein (LDL)‐derived cholesterol in human fibroblasts. To perform this study, three different culture conditions were used that included fibroblasts grown in lipoprotein‐deficient serum (LPDS), LPDS supplemented with LDL, and LPDS supplemented with LDL, followed by equilibration in the absence of LDL to allow the transport of LDL‐derived cholesterol from endocytic compartments and equilibration of cellular sterol pools. The results from this study indicated that in addition to the NPC1 gene/protein, the NPC2 gene/protein was also downregulated by LDL‐derived cholesterol‐dependent feedback inhibition and that downregulation of both the NPC1 and NPC2 genes/proteins was associated with the sequestration of LDL‐derived cholesterol within endocytic compartments, including late endosomes/lysosomes after equilibration. Therefore, it is proposed that physiological and coordinate downregulation of the NPC1 and NPC2 genes/proteins promotes the sequestration of LDL‐derived cholesterol within endocytic compartments and serves a role in maintaining intracellular cholesterol homeostasis. J. Cell. Biochem. 108: 1102–1116, 2009. © 2009 Wiley‐Liss, Inc.
Generation of a human immunodeficiency virus type 1 chronically infected monkey B cell line expressing low levels of endogenous TRIM5α
Authors: Ridolfi Barbara , Catone Stefania , Sgarbanti Marco , Sernicola Leonardo , Battistini Angela , Parolin Cristina , Titti Fausto , Borsetti Alessandra
Published: September 2009

Several innate cellular antiviral factors exist in mammalian cells that prevent the replication of retroviruses. Among them, the tripartite motif protein (TRIM)5α has been shown to block human immunodeficiency virus type 1 (HIV‐1) infection in several types of Old World monkey cells. Here we report a novel HIV‐1 chronically infected monkey B cell line, F6/HIV‐1, characterized by very low levels of TRIM5α expression that allows HIV‐1 to overcome the restriction. Virus produced by F6/HIV‐1 cells fails to infect monkey cells but retains the ability to infect human peripheral blood mononuclear cells (PBMCs) and T cell lines, although with a reduced infectivity compared to the input virus. Ultrastructural analyses revealed the presence of budding virions at the F6/HIV‐1 cells plasma membrane characterized by a typical conical core shell. To our knowledge F6/HIV‐1 is the first monkey cell line chronically infected by HIV‐1 and able to release infectious particles thus representing a useful tool to gain further insights into the molecular mechanisms of HIV‐1 pathogenesis. J. Cell. Physiol. 221: 760–765, 2009. © 2009 Wiley‐Liss, Inc.
Expression of RIZ1 protein (Retinoblastoma‐interacting zinc‐finger protein 1) in prostate cancer epithelial cells changes with cancer grade progression and is modulated in vitro by DHT and E2
Authors: Rossi Valentina , Staibano Stefania , Abbondanza Ciro , Pasquali Daniela , De Rosa Caterina , Mascolo Massimo , Bellastella Giuseppe , Visconti Daniela , De Bellis Annamaria , Moncharmont Bruno , De Rosa Gaetano , Puca Giovanni Alfredo , Bellastella Antonio , Sinisi Antonio Agostino
Published: September 2009

The nuclear protein methyl‐transferase Retinoblastoma‐interacting zinc‐finger protein 1 (RIZ1) is considered to be a downstream effector of estrogen action in target tissues. Silencing of RIZ1 expression is common in many tumors. We analyzed RIZ1 expression in normal and malignant prostate tissue and evaluated whether estradiol (E2) or dihydrotestosterone (DHT) treatment modulated RIZ1 in cultured prostate epithelial cells (PEC). Moreover, we studied the possible involvement of RIZ1 in estrogen action on the EPN prostate cell line, constitutively expressing both estrogen receptor (ER)‐α and β. RIZ1 protein, found in the nucleus of normal PECs by immunohistochemistry, was progressively lost in cancer tissues as the Gleason score increased and was only detected in the cytoplasmic compartment. RIZ1 transcript levels, as assayed by semi‐quantitative RT‐PCR in primary PEC cultures, were significantly reduced in cancer cells (P < 0.05). In EPN DHT treatment significantly increased RIZ1 transcript and protein levels (P < 0.05); E2 induced a reduction of S phase without significant changes of RIZ1 expression. In E2‐treated EPN cell extracts RIZ co‐immunoprecipitated with ERβ and ERα. Our data demonstrate that RIZ1 is expressed in normal PECs and down‐regulated in cancer cells, with a switch of its sub‐cellular localization from the nucleus to the cytoplasm upon cancer grade progression. RIZ1 expression levels in the PECs were modulated by DHT or E2 treatment in vitro. Furthermore, the E2 effects on ER‐expressing prostate cells involve RIZ1, which confirms a possible role for ER‐mediated pathways in a non‐classic E2‐target tissue. J. Cell. Physiol. 221: 771–777, 2009. © 2009 Wiley‐Liss, Inc.
ROCK pathway participates in the processes that 15‐hydroxyeicosatetraenoic acid (15‐HETE) mediated the pulmonary vascular remodeling induced by hypoxia in rat
Authors: Ma Jun , Liang Shujun , Wang Zhigang , Zhang Lei , Jiang Jing , Zheng Jinhua , Yu Lei , Zheng Xiaodong , Wang Ruifang , Zhu Daling
Published: September 2009

15‐Hydroxyeicosatetraenoic acid (15‐HETE), a product of arachidonic acid (AA) catalyzed by 15‐lipoxygenase (15‐LO), plays an essential role in hypoxic pulmonary arterial hypertension. We have previously shown that 15‐HETE inhibits apoptosis in pulmonary artery smooth muscle cells (PASMCs). To test the hypothesis that such an effect is attributable to the hypoxia‐induced pulmonary vascular remodeling (PVR), we performed these studies. We found subtle thickening of proximal media/adventitia of the pulmonary arteries (PA) in rats that had been exposed to hypoxia. This was associated with an up‐regulation of the anti‐apoptotic Bcl‐2 expression and down‐regulation of pro‐apoptotic caspase‐3 and Bax expression in PA homogenates. Nordihydroguaiaretic acid (NDGA), which inhibits the generation of endogenous 15‐HETE, reversed all the alterations following hypoxia. In situ hybridization histochemistry and immunocytochemistry showed that the 15‐LO‐1 mRNA and protein were localized in pulmonary artery endothelial cells (PAECs), while the 15‐LO‐2 mRNA and protein were localized in both PAECs and PASMCs. Furthermore, the Rho‐kinase (ROCK) pathway was activated by both endogenous and exogenous 15‐HETE, alleviating the serum deprivation (SD)‐induced PASMC apoptosis. Thus, these findings indicate that 15‐HETE protects PASMC from apoptosis, contributing to pulmonary vascular medial thickening, and the effect is, at least in part, mediated via the ROCK pathway. J. Cell. Physiol. 222:82–94, 2010. © 2009 Wiley‐Liss, Inc.
The utility of thoracic ultrasound before local anesthetic video‐assisted thoracoscopy in patients with suspected pleural malignancy
Authors: Medford Andrew R. L.
Published: September 2009

Video‐assisted thoracoscopy under local anesthesia (VAT‐LA) is a key investigation in the diagnosis and management of suspected malignant pleural effusion. Two problems encountered at VAT‐LA are accessing the pleural space and fibrinous intrapleural septa. Thoracic sonography (TUS) is known to facilitate thoracocentesis after dry tap but has not been studied in detail before VAT‐LA. We report a case of lateral decubitus pre‐VAT TUS that helped locate the optimal access to the pleural space and demonstrated fibrinous intrapleural septation, thereby affecting the decision to avoid thoracoscopic pleurodesis. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2009
Survival, differentiation, and reversal of heroin neurobehavioral teratogenicity in mice by transplanted neural stem cells derived from embryonic stem cells
Authors: Kazma Meital , Izrael Michal , Revel Michel , Chebath Judith , Yanai Joseph
Published: September 2009

Cell therapies in animal models of neurobehavioral defects are normally derived from neural stem cells (NSC) of the developing cortex. However, the clinical feasibility of NSC therapies would be greatly improved by deriving transplanted cells and from a tissue culture source that is self‐renewing, containing cells that potentially differentiate into the desired neuronal phenotypes. These cultures can be engineered to contain the appropriate factors to support their therapeutic action and likely evoke lesser immune reactions. In the current study, we employed our model of mice neurobehaviorally impaired via prenatal exposure to heroin, to test the therapeutic efficacy of NSC derived from murine embryonic stem cells culture (ESC). The culture contained elongated bipolar cells, 90% of which are positive for nestin, the intermediate filament protein found in neural precursors. After removal of growth factors, the NSC differentiated into neurons (34.0% ± 3.8% NF‐160 positive), including cholinergic cells (ChAT positive), oligodendrocytes (29.9% ± 4.2% O4), and astrocytes (36.1% ± 4.7% GFAP positive). Rreverse transcriptase polymerase chain reaction (RT‐PCR) analysis confirmed the immunocytochemical findings. Mice made deficient in Morris maze behavior by prenatal heroin exposure (10 mg/kg heroin S.C. on gestational days 9–18) were transplanted into the hippocampusregion on postnatal day 35 with the ES culture‐derived NSC (ES‐NSC) labeled with dialkylcarbocyanine (Dil) cell tracker. Dil+ and NF160+ cells were detected in the hippocampal region (50% ± 8% survival). The transplantation completely restored maze performance to normal; e.g., on day 3, transplantation improved the behavior from the deficient level of 11.9‐sec latency to the control of 5.6‐sec latency (44.5% improvement). © 2009 Wiley‐Liss, Inc.
Immediate anti‐tumor necrosis factor‐α (etanercept) therapy enhances axonal regeneration after sciatic nerve crush
Authors: Kato Kinshi , Liu Huaqing , Kikuchi Shin‐ichi , Myers Robert R. , Shubayev Veronica I.
Published: September 2009

Peripheral nerve regeneration begins immediately after injury. Understanding the mechanisms by which early modulators of axonal degeneration regulate neurite outgrowth may affect the development of new strategies to promote nerve repair. Tumor necrosis factor‐α (TNF‐α) plays a crucial role in the initiation of degenerative cascades after peripheral nerve injury. Here we demonstrate using real‐time Taqman quantitative RT‐PCR that, during the time course (days 1–60) of sciatic nerve crush, TNF‐α mRNA expression is induced at 1 day and returned to baseline at 5 days after injury in nerve and the corresponding dorsal root ganglia (DRG). Immediate therapy with the TNF‐α antagonist etanercept (fusion protein of TNFRII and human IgG), administered systemically (i.p.) and locally (epineurially) after nerve crush injury, enhanced the rate of axonal regeneration, as determined by nerve pinch test and increased number of characteristic clusters of regenerating nerve fibers distal to nerve crush segments. These fibers were immunoreactive for growth associated protein‐43 (GAP‐43) and etanercept, detected by anti‐human IgG immunofluorescence. Increased GAP‐43 expression was found in the injured nerve and in the corresponding DRG and ventral spinal cord after systemic etanercept compared with vehicle treatments. This study established that immediate therapy with TNF‐α antagonist supports axonal regeneration after peripheral nerve injury. © 2009 Wiley‐Liss, Inc.
“Juvenile stress” alters maturation‐related changes in expression of the neural cell adhesion molecule L1 in the limbic system: Relevance for stress‐related psychopathologies
Authors: Tsoory M.M. , Guterman A. , Richter‐Levin G.
Published: September 2009

L1 is critically involved in neural development and maturation, activity‐dependent synaptic plasticity, and learning processes. Among adult rats, chronic stress protocols that affect L1 functioning also induce impaired cognitive and neural functioning and heightened anxiety reminiscent of stress‐induced mood and anxiety disorders. Epidemiological studies indicate that childhood trauma is related predominantly to higher rates of both mood and anxiety disorders in adulthood and is associated with altered limbic system functioning. Exposing rats to stress during the juvenile period (“juvenile stress”) has comparable effects and was suggested as a model of induced predisposition for these disorders. This study examined the effects of juvenile stress on rats aversive learning and on L1 expression soon after exposure and in adulthood, both following additional exposure to acute stress and in its absence. Adult juvenile‐stressed rats exhibited enhanced cued fear conditioning, reduced novel‐setting exploration, and impaired avoidance learning. Furthermore, juvenile stress increased L1 expression in the BLA, CA1, DG, and EC both soon after the stressful experience and during adulthood. It appears that juvenile stress affects the normative maturational decrease in L1 expression. The results support previous indications that juvenile stress alters the maturation of the limbic system and further support a role for L1 regulation in the mechanisms that underlie the predisposition to exhibit mood and/or anxiety disorders in adulthood. Furthermore, the findings support the “network hypothesis,” which postulates that information‐processing problems within relevant neural networks might underlie stress‐induced mood and anxiety disorders. © 2009 Wiley‐Liss, Inc.
Uptake of ferrous iron by cultured rat astrocytes
Authors: Tulpule Ketki , Robinson Stephen R. , Bishop Glenda M. , Dringen Ralf
Published: September 2009

Astrocytes are considered to play an important role in iron homeostasis of the brain, yet the mechanisms involved in the uptake of iron into astrocytes remain elusive. To investigate the uptake of iron into astrocytes, we have applied ferric ammonium citrate (FAC) to rat astrocyte‐rich primary cultures. These cultures express the mRNAs of two membrane‐bound ferric reductases, Dcytb and SDR2, and reduce extracellular ferric iron (100 μM) with a rate of 3.2 ± 0.4 nmol/(hr × mg). This reduction rate is substantially lower than the rate of cellular iron accumulation from 100 μM FAC [24.7 ± 8.9 nmol/(hr × mg)], which suggests that iron accumulation from FAC does at best partially depend on extracellular ferric reduction. Nonetheless, when the iron in FAC was almost completely reduced by an excess of exogenous ascorbate, astrocytes accumulated iron in a time‐ and concentration‐dependent manner with specific iron accumulation rates that increased linearly for concentrations of up to 100 μM ferrous iron. This accumulation was attenuated by lowering the incubation temperature, by the presence of ferrous iron chelators, or by lowering the pH from 7.4 to 6.8. These data indicate that, in addition to the DMT1‐mediated uptake of ferrous iron, astrocytes can accumulate ferric and ferrous iron by mechanisms that are independent of DMT1 or transferrin. © 2009 Wiley‐Liss, Inc.
Characterization of green‐tissue protein extract from alfalfa (Medicago sativa) exploiting a 3‐D technique
Authors: Aguilar Oscar , Glatz Charles E. , Rito‐Palomares Marco
Published: September 2009

There is a growing interest of pharmaceutical companies for plant‐based production systems. To facilitate the general acceptance of plants as bioreactors, the establishment of efficient downstream operations is critical. It has been proposed that a better understanding of the properties of the contaminant proteins can benefit downstream processing design and operation. The coupled application of 2‐DE with aqueous two‐phase partitioning has been suggested as a practical 3‐D method to characterize potential contaminant proteins from plant extracts. The application of this novel 3‐D approach to a complex protein extract from alfalfa (Medicago sativa) containing a model recombinant protein (human granulocyte colony stimulating factor (hG‐CSF)) resulted in the quantification of 55 protein spots. The 3‐D properties (Mr, pI, and Kp) obtained for 17 proteins comprising 69% of the alfalfa proteins, allowed the proposal of a prefractionation step as well as the identification of the target molecule (rG‐CSF) from bulk of alfalfa proteins. The information obtained from this experimental approach was useful for the identification of the potential contaminant proteins that will occur in alfalfa when this plant is used as a host for recombinant proteins. Additionally, this method will assist in the design of adequate purification strategies for recombinant proteins expressed in alfalfa green tissue.
MEKC determination of vanadium from mineral ore and crude petroleum oil samples using precapillary chelation with bis(salicylaldehyde)tetramethyl‐ethylenediimine
Authors: Mirza Muhammad Aslam , Kandhro Abdul Jabbar , Khuhawar Muhammad Yar , Arain Rafee
Published: September 2009

An analytical procedure has been developed for the separation of Cu(II), Ni(II), Co(II), Fe(II), Pd(II), Th(IV), V(IV), and determination of Fe(II), Co(II), Ni(II), and V(IV) by MEKC after chelation with bis(salicylaldehyde)tetramethylethylenediimine (H2SA2Ten). Uncoated fused silica capillary was used with an applied voltage of 30 kV with photo‐diode array detection at 228 nm. SDS was added as micellar medium at pH 8.2 with sodium tetraborate buffer (0.1 M). Linear calibrations were established within 0.015–1000 μg/mL of each element with LOD within 5–67 ng/mL. The method was applied for the determination of vanadium from crude oil and ore samples in the range 0.34–2.40 and 114.2–720.7 μg/g with RSD 1.7–3.8 and 0.98–2.30% (n = 3), respectively. Fe, Ni, and Co present in crude oil and ore samples were also determined with RSD 1.3–2.8, 1.1–4.1, and 1.2–3.5% (n = 3), respectively. The results were compared with that of supplier's specifications and atomic absorption spectrometry (AAS). Method was evaluated by standard addition technique.
Comparison of solidification of floating drop and homogenous liquid–liquid microextractions for the extraction of two plasticizers from the water kept in PET‐bottles
Authors: Yamini Yadollah , Ghambarian Mahnaz , Khalili‐Zanjani Mohammad Reza , Faraji Mohammad , Shariati Shahab
Published: September 2009

Two approaches based on solidification of floating drop microextraction (SFDME) and homogenous liquid–liquid microextraction (HLLE) were compared for the extraction and preconcentration of di‐(2‐ethylhexyl) phthalate (DEHP) and di‐(2‐ethylhexyl) adipate (DEHA) from the mineral water samples. In SFDME, a floated drop of the mixture of acetophenone/1‐undecanol (1:8) was exposed on the surface of the aqueous solution and extraction was permitted to occur. In HLLE, a homogenous ternary solvent system was used by water/methanol/chloroform and the phase separation phenomenon occurred by salt addition. Under the optimal conditions, the LODs for the two target plasticizers (DEHA and DEHP), obtained by SFDME–GC‐FID and HLLE–GC‐FID, were ranged from 0.03 to 0.01 μg/L and 0.02 to 0.01 μg/L, respectively. HLLE provided higher preconcentration factors (472.5‐ and 551.2‐fold) within the shorter extraction time as well as better RSDs (4.5–6.9%). While, in SFDME, high preconcentration factors in the range of 162–198 and good RSDs in the range of 5.2–9.6% were obtained. Both methods were applied for the analysis of two plasticizers in different water samples and two target plasticizers were found in the bottled mineral water after the expiring time and the boiling water was exposed to a polyethylene vial.
Inherent peak compression of charged analytes in electrochromatography
Authors: Nischang Ivo , Tallarek Ulrich
Published: September 2009

This work resolves peak compression of charged analytes in CEC with strong cation‐exchange stationary phase particles. By combining electrochromatographic peak shape analysis with the results of numerical simulations and confocal laser scanning microscopy in the packed capillaries, we identify electrical field‐induced concentration polarization as the key physical phenomenon responsible for the inherent existence of local electrical field gradients on the scale of an individual support particle. Consequently, positive and negative field gradients exist between and inside the particles along the whole packing. Their intensity depends on the particles cation‐selectivity (governed by the particles volume charge density and the mobile phase ionic strength) and the applied field strength. The interplay of these local field gradients with the analytes retention (intraparticle adsorption) determines whether fronting, tailing, or spiked analyte peaks are observed, and it provides a mechanism by which strongly retained analytes can be eluted over long distances with little zone dispersion. Our analysis explains the “anomalous” peak compression effects with strong cation‐exchange particles, which have been reported more than a decade ago (Smith, N. W., Evans, M. B., Chromatographia 1995, 41, 197–203) and since then remained largely unresolved.
Randomized controlled trial: Comparative efficacy for the treatment of facial telangiectasias with 532 nm versus 940 nm diode laser
Authors: Tierney Emily , Hanke C. William
Published: September 2009

Background

While the 532 nm wavelength has been demonstrated to be effective for facial telangiectasias, 940 nm is a novel wavelength which has only been reported in case reports. While both the 532 and 940 nm wavelengths are effective for facial telangiectasias, we lack evidence to support whether one wavelength is superior.

Study Design

Randomized, blinded split‐faced trial for the 532 and 940 nm diode laser wavelengths. Side effects of erythema, crusting, swelling, and blistering (0–5 scale, 0 = not present, 1 = trace, 5 = severe) were assessed. Prior to treatment and at 2 months after a series of two treatments, telangiectasias were assessed (1–10 scale, 1 = focal telangiectasias, 10 = diffuse telangiectasias). Assessment of the degree of improvement in facial telangiectasias was performed by two blinded non‐treating physician evaluators from patient photographs.

Results

A total of 24 facial anatomic sites were treated with the 532 and 940 nm wavelengths. Presence and severity of side effects of erythema, crusting, swelling, blistering (0–5 scale, 0 = not present, 1 = trace, 5 = severe) were assessed. Pain associated with the laser treatment was rated as significantly less for the 940 nm wavelength relative to the 532 nm wavelength. Erythema post‐treatment was significantly less with 940 nm relative to 532 nm. Significant crusting and swelling were only reported with the 532 nm wavelength. The mean percentage improvement with the 940 nm wavelength (63.0%) was greater than that achieved with the 532 nm wavelength (47.8%) (P<0.05). On photographic evaluation, 940 nm was significantly more efficacious for larger caliber vessels than 532 nm. Both wavelengths were equally efficacious for smaller caliber vessels.

Conclusions

While both 532 and 940 nm diode laser produced significant improvement in facial telangiectasias, greater efficacy was found with 940 nm as well as a significantly more tolerable side effect profile. Lasers Surg. Med. 41:555–562, 2009. © 2009 Wiley‐Liss, Inc.
Pulsed dye laser‐induced inflammatory response and extracellular matrix turnover in rat vocal folds and vocal fold fibroblasts
Authors: Lin Ya , Yamashita Masaru , Zhang Jingxian , Ling Changying , Welham Nathan V.
Published: September 2009

Background and Objectives

Disruption of the vocal fold extracellular matrix (ECM) can induce a profound and refractory dysphonia. Pulsed dye laser (PDL) irradiation has shown early promise as a treatment modality for disordered ECM in patients with chronic vocal fold scar; however, there are limited data addressing the mechanism by which this laser energy might induce cellular and extracellular changes in vocal fold tissues. In this study, we examined the inflammatory and ECM modulating effects of PDL irradiation on normal vocal fold tissues and cultured vocal fold fibroblasts (VFFs).

Study Design/Materials and Methods

We evaluated the effects of 585 nm PDL irradiation on inflammatory cytokine and collagen/collagenase gene transcription in normal rat vocal folds in vivo (3–168 hours following delivery of ∼39.46 J/cm2 fluence) and VFFs in vitro (3–72 hours following delivery of 4.82 or 9.64 J/cm2 fluence). We also examined morphological vocal fold tissue changes 3 hours, 1 week, and 1 month post‐irradiation.

Results

PDL irradiation altered inflammatory cytokine and procollagen/collagenase expression at the transcript level, both in vitro and in vivo. Additionally, PDL irradiation induced an inflammatory repair process in vivo that was completed by 1 month with preservation of normal tissue morphology.

Conclusions

PDL irradiation can modulate ECM turnover in phenotypically normal vocal folds. Additional work is required to determine if these findings extend to disordered ECM, such as is seen in vocal fold scar. Lasers Surg. Med. 41:585–594, 2009. © 2009 Wiley‐Liss, Inc.
Postural tremor in X‐linked spinal and bulbar muscular atrophy
Authors: Hanajima Ritsuko , Terao Yasuo , Nakatani‐Enomoto Setsu , Hamada Masashi , Yugeta Akihiro , Matsumoto Hideyuki , Yamamoto Tomotaka , Tsuji Shoji , Ugawa Yoshikazu
Published: September 2009

Postural tremor is a common initial symptom in spinal and bulbar muscular atrophy (SBMA), but its pathophysiological mechanisms remain to be studied. This study was undertaken to examine the physiological mechanisms underlying postural tremor in SBMA. For eight patients (36–63 years old) with genetically confirmed SBMA, we recorded surface electromyograms (EMGs) from the forearm muscles and hand movements with an accelerometer (ACC) while maintaining a posture with and without a weight load. We then analyzed their power spectra and coherence. The peak tremor frequency was 6–9 Hz in seven patients and 2–3 Hz in one patient. Oscillatory movements were associated with EMG activity in five patients, but not in three patients. Weight loads and postural changes affected the tremor frequency in all patients. Tremor was classified as “reflex tremor” in five patients and “mechanical tremor” in three patients. These results suggest that peripheral factors play important roles in tremor genesis in SBMA, although its clinical features resemble essential tremor. Subclinical sensory disturbance or a decrease of motor unit numbers might be candidates for such peripheral factors contributing to tremor genesis in SBMA. © 2009 Movement Disorder Society
A π‐stacked and conjugated hybrid based on poly(N‐vinylcarbazole) postfunctionalized with terfluorene for stable deep‐blue hole‐transporting materials
Authors: Xie Ling‐Hai , Deng Xian‐Yu , Chen Lin , Chen Shu‐Fen , Liu Ran‐Ran , Hou Xiao‐Ya , Wong King‐Young , Ling Qi‐Dan , Huang Wei
Published: September 2009

The combination of π‐stacked with π‐conjugated building blocks offers an essential strategy to construct multifunctional organic semiconductors (MOSs) with the unique optoelectrical properties. Covalent hybrids can efficiently avoid the intrinsic phase‐separation defects in corresponding blend system. In this contribution, poly(vinylcarbazole) tethered with terfluorene, PVK‐TF, as a double‐channeled π‐stacked and π‐conjugated hybrid (SCH), has been constructed via Friedal‐Crafts click postmodification (FCCP). The chemical structure and optoelectrical property were determined by GPC, UV–vis, PL, TGA, DSC, and CV. Its PL spectra in the annealing thin film at N2 atmosphere without low‐energy emission bands centered at the 530 nm indicates that no π‐stacks between carbazole and TF or among TFs dominate the whole condensed phase, which is in agreement with the intrachain T‐shaped π‐pitched motifs in molecular modeling simulation due to steric hindrance effect in complicated diarylfluorenes (CDAFs). A supporting prototype stable deep‐blue PLED was successfully obtained with an Internationale de l'Eclairage (CIE) coordinates of (0.20, 0.10) and a width at half maximum (FWHM) of about 60 nm at high current density of 100 mA/cm2 (35 V). Deep‐blue PVK‐TF is a promising MOS for hole‐transporting and host materials. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5221–5229, 2009
Role of dispersion stabilizer with hydroxy groups in preparation of monodisperse polylactide microspheres
Authors: Muranaka Makoto , Ono Tsutomu
Published: September 2009

Monodisperse poly(D,L‐lactide) (PDLLA) microspheres were prepared by dispersion polymerization of D,L‐lactide in xylene/heptane (1/2, v/v) with poly[(dodecyl methacrylate)‐co‐(2‐hydroxyethyl methacrylate)] (P(DMA‐co‐HEMA)) as a dispersion stabilizer. P(DMA‐co‐HEMA) contains hydroxy groups, which act as an initiation group for pseudoanionic dispersion polymerization. The best coefficient of variation (CV) values concerning particle diameter distribution and the particle diameter of obtained PDLLA microspheres were 3.7% and 5.3 μm, respectively. The particle diameter decreased with increasing concentration of P(DMA‐co‐HEMA) and HEMA maintained low CV (<10%) values. As a result, monodisperse PDLLA microspheres ranging from 1.3 to 5.3 μm were obtained. In addition, it was found that monodisperse PDLLA microspheres were obtained by sufficient capture of growing polymers and monomers in the particle growth stage. Therefore, the HEMA concentration in P(DMA‐co‐HEMA) strongly affecting the capturing capability is the most important factor. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5230–5240, 2009
Controlled vinyl‐type polymerization of norbornene with a Nickel(II) diphosphinoamine/methylaluminoxane catalytic system
Authors: Vougioukalakis Georgios C. , Stamatopoulos Ioannis , Petzetakis Nikolaos , Raptopoulou Catherine P. , Psycharis Vassilis , Terzis Aris , Kyritsis Panayotis , Pitsikalis Marinos , Hadjichristidis Nikos
Published: September 2009

A novel nickel‐based complex coordinated with an asymmetric diphosphinoamine ligand was synthesized and fully characterized. Single crystals of good quality were also obtained, and the solid‐state structure of the complex was studied via X‐rays diffraction. The catalytic activity of this Ni(II) complex in the vinyl‐type polymerization of norbornene was studied with methylaluminoxane (MAO) as the cocatalyst/activator. The influence of the reaction time, the equivalents of MAO used, and the concentration of the monomer on: (i) the activity of the catalytic system; (ii) the isolated yield of the polymer; and (iii) the molecular weight and molecular weight distribution of the polymer were investigated. The isolated polynorbornene (PNB) yields are significantly higher compared with those reported for other similar nickel‐based systems. The as‐obtained PNBs are characterized by high molecular weights and relatively narrow and monomodal molecular weight distributions (amongst the narrowest reported in the literature). The linear dependence of the molecular weight of the obtained PNB on the concentration of norbornene points toward a controlled polymerization reaction. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5241–5250, 2009
Synthesis, photopolymerization, and adhesive properties of new bisphosphonic acid monomers for dental application
Authors: Catel Yohann , Degrange Michel , Pluart Loïc Le , Madec Pierre‐Jean , Pham Thi‐Nhàn , Chen Fei , Cook Wayne D.
Published: September 2009

Four new monomers, 3‐(N‐methylacrylamido)propylidenebisphosphonic acid, 3‐(N‐propyl‐acrylamido)propylidenebisphosphonic acid, 3‐(N‐hexylacrylamido)propylidenebisphosphonic acid, and 3‐(N‐octylacrylamido)propylidenebisphosphonic acid, have been synthesized in good yields and fully characterized by 1H, 13C, 31P NMR, and HRMS. The copolymerization of these monomers with N,N′‐diethyl‐1,3‐bis(acrylamido)propane (DEBAAP) has been investigated with differential scanning calorimetry. These mixtures show a higher reactivity than DEBAAP. New self‐etch dental primers, based on these acrylamide monomers, have been formulated. Dentin shear bond strength measurements have shown that primers based on these bisphosphonic acids assure a strong bond between the tooth substance and a dental composite. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5258–5271, 2009