bluuebunny/crossref_metadata_2025 huggingface dataset:
Immature Copper-Zinc Superoxide Dismutase and Familial Amyotrophic Lateral Sclerosis
Authors: Seetharaman Sai V. , Prudencio Mercedes , Karch Celeste , Holloway Stephen P. , Borchelt David R. , Hart P. John
Published: July 2009

Mutations in human copper-zinc superoxide dismutase (SOD1) cause an inherited form of amyotrophic lateral sclerosis (ALS, Lou Gehrig’s disease, motor neuron disease). Insoluble forms of mutant SOD1 accumulate in neural tissues of human ALS patients and in spinal cords of transgenic mice expressing these polypeptides, suggesting that SOD1-linked ALS is a protein misfolding disorder. Understanding the molecular basis for how the pathogenic mutations give rise to SOD1 folding intermediates, which may themselves be toxic, is therefore of keen interest. A critical step on the SOD1 folding pathway occurs when the copper chaperone for SOD1 (CCS) modifies the nascent SOD1 polypeptide by inserting the catalytic copper cofactor and oxidizing its intrasubunit disulfide bond. Recent studies reveal that pathogenic SOD1 proteins coming from cultured cells and from the spinal cords of transgenic mice tend to be metal-deficient and/or lacking the disulfide bond, raising the possibility that the disease-causing mutations may enhance levels of SOD1-folding intermediates by preventing or hindering CCS-mediated SOD1 maturation. This mini-review explores this hypothesis by highlighting the structural and biophysical properties of the pathogenic SOD1 mutants in the context of what is currently known about CCS structure and action. Other hypotheses as to the nature of toxicity inherent in pathogenic SOD1 proteins are not covered.
Liver Cyst Cytokines Promote Endothelial Cell Proliferation and Development
Authors: Brodsky Kelley S. , McWilliams Ryan R. , Amura Claudia R. , Barry Nicholas P. , Doctor R. Brian
Published: July 2009

Autosomal dominant polycystic kidney (ADPKD) is highly prevalent genetic disease. Liver cyst disease is the most common extrarenal manifestation in ADPKD and accounts for up to 10% of ADPKD morbidity and mortality. The clinical features of ADPKD liver disease arise from dramatic increases in liver cyst volumes. To identify mechanisms that promote liver cyst growth, the present study characterized the degree of vascularization of liver cyst walls and determined that cyst-specific cytokines and growth factors can drive endothelial cell proliferation and development. Microscopic techniques demonstrated liver cyst walls are well vascularized. A comparative analysis found the vascular density in free liver cyst walls was greater in mice than in humans. Treatment of human micro-vascular endothelial cells (HMEC-1) with human liver cyst fluid (huLCF) induced a rapid increase in vascular endothelium growth factor receptor 2 (VEGFR2) phosphorylation that persisted for 45–60 min and was blocked by 20 μM SU5416, a VEGFR tyrosine kinase inhibitor. Similarly, huLCF treatment of HMEC-1 cells induced an increase in the cell proliferation rate (131 ± 6% of control levels; P > 0.05) and the degree of vascular development (‘tube’ diameter assay: 92 ± 14 μm for huLCF vs. 12 ± 7 μm for vehicle); P > 0.05). Both cell proliferation and vascular development were sensitive to SU5416. These studies indicate that factors secreted by liver cyst epithelia can activate VEGF signaling pathways and induce endothelial cell proliferation and differentiation. The present studies suggest that targeting VEGFR2-dependent angiogenesis may be an effective therapeutic strategy in blocking ADPKD liver cyst vascularization and growth.
Enterovirus 71 Infection of Human Dendritic Cells
Authors: Lin Yu-Wen , Wang Shainn-Wei , Tung Yuk-Ying , Chen Shun-Hua
Published: July 2009

Enterovirus 71 (EV71) causes death and long-term neurologic sequelae in hundreds of thousands of young children, but its pathogenesis remains elusive. Dendritic cells (DCs) play a crucial role in antiviral immunity by functioning as professional antigen-presenting cells to prime T cells and by secreting cytokines to modulate immune responses. Here, we show that EV71 productively infected human immature DCs and expressed viral antigen in DCs. EV71 entry into DCs was partially mediated by DC-SIGN. Further analyses revealed that EV71 increased the viability, activation, release of cytokines, interleukin-6, interleukin-12, and tumor necrosis factor-α in DCs. Moreover, EV71 enabled DCs to stimulate T-cell proliferation. Collectively, these findings suggest that EV71 infection of human DCs in vivo is very likely to elicit protective immunity, because in infected mice, both T cells and IL-6 function to reduce mortality.
An Improved Cloud Classification Algorithm for China’s FY-2C Multi-Channel Images Using Artificial Neural Network
Authors: Liu Yu , Xia Jun , Shi Chun-Xiang , Hong Yang
Published: July 2009

The crowning objective of this research was to identify a better cloud classification method to upgrade the current window-based clustering algorithm used operationally for China’s first operational geostationary meteorological satellite FengYun-2C (FY-2C) data. First, the capabilities of six widely-used Artificial Neural Network (ANN) methods are analyzed, together with the comparison of two other methods: Principal Component Analysis (PCA) and a Support Vector Machine (SVM), using 2864 cloud samples manually collected by meteorologists in June, July, and August in 2007 from three FY-2C channel (IR1, 10.3-11.3 μm; IR2, 11.5-12.5 μm and WV 6.3-7.6 μm) imagery. The result shows that: (1) ANN approaches, in general, outperformed the PCA and the SVM given sufficient training samples and (2) among the six ANN networks, higher cloud classification accuracy was obtained with the Self-Organizing Map (SOM) and Probabilistic Neural Network (PNN). Second, to compare the ANN methods to the present FY-2C operational algorithm, this study implemented SOM, one of the best ANN network identified from this study, as an automated cloud classification system for the FY-2C multi-channel data. It shows that SOM method has improved the results greatly not only in pixel-level accuracy but also in cloud patch-level classification by more accurately identifying cloud types such as cumulonimbus, cirrus and clouds in high latitude. Findings of this study suggest that the ANN-based classifiers, in particular the SOM, can be potentially used as an improved Automated Cloud Classification Algorithm to upgrade the current window-based clustering method for the FY-2C operational products.
The pollen morphology of species of Gongylolepis (Mutisiae: Asteraceae) in the Venezuelan Guayana
Authors: Ubiergo Paola , Lapp Marlene , Torrecilla Pedro
Published: July 2009

Gongylolepis is composed for 15 species, endemic to the Guyana region. This is the largest genus of tribe Mutiseae in the area. Palynological features have been studied for some members of the Mutiseae, but not for Gongylolepis. We studied the pollen morphology of nine species of the genus, using samples from herbarium material. The observations were made in 10 to 15 pollen grains for species and features of the spines, colpus, polar axis, equatorial diameter, exine structure, pollen type, apertures, perforations and P/E ratio to determinate pollen shape, were analyzed. Observations and pictures were made with light microscope and scanning electron microscope. With this information, a matrix and conglomerate analysis was made. Gongylolepis pollen is tricolporate, spheroidal and mainly of great size. Differences in exine ornamentation were enough to discriminate the studied species. Spines are conical, with perforations near of the base, but with differences in the apex shape. The dendogram showed four groups, where the size, shape, exine ornamentation, spines, colpus and perforations were of importance to the classification of the species considered.
Trimer Stabilization, Oligomerization, and Antibody-Mediated Cell Surface Immobilization Improve the Activity of Soluble Trimers of CD27L, CD40L, 41BBL, and Glucocorticoid-Induced TNF Receptor Ligand
Authors: Wyzgol Agnes , Müller Nicole , Fick Andrea , Munkel Sabine , Grigoleit Goetz Ulrich , Pfizenmaier Klaus , Wajant Harald
Published: July 2009

For many ligands of the TNF family, trimer stability and oligomerization status are crucial determinants of receptor activation. However, for the immunostimulatory ligands CD27L, CD40L, 41BBL, and glucocorticoid-induced TNF receptor ligand (GITRL) detailed information regarding these requirements is lacking. Here, we comprehensively evaluated the effect of trimer stability and oligomerization on receptor activation by these ligands. Treatment with soluble Flag-tagged CD27L, 41BBL, and GITRL minimally activated receptor signaling, while Flag-CD40L was highly active. Oligomerization with anti-Flag Abs further enhanced the specific activity of Flag-CD40L 10-fold and of Flag-41BBL more than 200-fold, but it failed to activate Flag-CD27L and Flag-GITRL. We next investigated the relevance of trimer stability by introducing the tenascin-C (TNC) trimerization domain, yielding stabilized Flag-TNC-ligand trimers. Oligomerization with anti-Flag Ab potently activated signaling by Flag-TNC-CD27L and Flag-TNC-GITRL and, albeit to a lesser extent, Flag-TNC-CD40L and Flag-TNC-41BBL. Forced hexamerization, by introducing an Ig Fc domain, revealed that hexameric derivatives of Flag-TNC-41BBL, Flag-CD40L, and Flag-TNC-GITRL all activate receptor signaling with high efficiency, whereas hexameric Flag-CD27L variant left inactive. Finally, we attempted to selectively activate receptor signaling on targeted cells, by using Ab fragment (single-chain fragment variable region, scFv)-ligand fusion proteins, an approach previously applied to other TNF ligands. Target cell surface Ag-selective activation was achieved for scFv-41BBL, scFv-CD40L, and scFv-GITRL, although the latter two displayed already significant activity toward Ag-negative cells. In conclusion, our data establish that trimeric CD40L is active, 41BBL requires hexamerization, GITRL requires trimer stabilization, and CD27L requires trimer stabilization and oligomerization. Furthermore, surface immobilization might be exploited to gain locally enhanced ligand activity.
IL-8 Regulates Mucin Gene Expression at the Posttranscriptional Level in Lung Epithelial Cells
Authors: Bautista Maria V. , Chen Yajun , Ivanova Vessela S. , Rahimi Michael K. , Watson Alan M. , Rose Mary C.
Published: July 2009

Airway inflammation and mucus hypersecretion/overproduction/obstruction are pathophysiological characteristics of cystic fibrosis, asthma, and chronic obstructive pulmonary disease. Up-regulation of airway mucin genes by inflammatory/immune response mediators is one of the major contributors to mucin overproduction. IL-8, a potent proinflammatory mediator and neutrophil chemoattractant, is present at high levels in the airway secretions of such patients. In this study, the effects of IL-8 on expression of two major airway mucin genes, MUC5AC and MUC5B, were evaluated. IL-8 increased the mRNA abundance of both mucin genes in two human respiratory tract-derived cell lines (A549 and NCI-H292) in a time- and concentration-dependent manner. IL-8 also increased MUC5AC and MUC5B mRNA levels in primary normal differentiated human bronchial epithelial cells, with a high concentration of IL-8 required to increase MUC5B mRNA levels. IL-8 did not transcriptionally up-regulate MUC5AC gene expression, but rather increased the stability of the MUC5AC transcript, suggesting regulation at the posttranscriptional level. In addition, IL-8 altered the levels of RNA-binding proteins to specific domains in the 3′-untranslated region of the MUC5AC transcript. Taken together, these data indicate that the IL-8-induced binding of RNA-binding proteins to the 3′-untranslated region of MUC5AC is a potential mechanism for regulating MUC5AC gene expression at the posttranscriptional level, thus suggesting a new role whereby IL-8 sustains mucin gene expression in inflamed airways.
Novel MHC Class I Structures on Exosomes
Authors: Lynch Sarah , Santos Susana G. , Campbell Elaine C. , Nimmo Ailish M. S. , Botting Catherine , Prescott Alan , Antoniou Antony N. , Powis Simon J.
Published: July 2009

Exosomes are nanometer-sized vesicles released by a number of cell types including those of the immune system, and often contain numerous immune recognition molecules including MHC molecules. We demonstrate in this study that exosomes can display a significant proportion of their MHC class I (MHC I) content in the form of disulfide-linked MHC I dimers. These MHC I dimers can be detected after release from various cell lines, human monocyte-derived dendritic cells, and can also be found in human plasma. Exosome-associated dimers exhibit novel characteristics which include 1) being composed of folded MHC I, as detected by conformational-dependent Abs, and 2) dimers forming between two different MHC I alleles. We show that dimer formation is mediated through cysteine residues located in the cytoplasmic tail domains of many MHC I molecules, and is associated with a low level of glutathione in exosomes when compared with whole cell lysates. We propose these exosomal MHC I dimers as novel structures for recognition by immune receptors.
Maternal Exposure to Secondhand Cigarette Smoke Primes the Lung for Induction of Phosphodiesterase-4D5 Isozyme and Exacerbated Th2 Responses: Rolipram Attenuates the Airway Hyperreactivity and Muscarinic Receptor Expression but Not Lung Inflammation and Atopy
Authors: Singh Shashi P. , Mishra Neerad C. , Rir-sima-ah Jules , Campen Mathew , Kurup Viswanath , Razani-Boroujerdi Seddigheh , Sopori Mohan L.
Published: July 2009

Airway hyperreactivity (AHR), lung inflammation, and atopy are clinical signs of allergic asthma. Gestational exposure to cigarette smoke (CS) markedly increases the risk for childhood allergic asthma. Muscarinic receptors regulate airway smooth muscle tone, and asthmatics exhibit increased AHR to muscarinic agonists. We have previously reported that in a murine model of bronchopulmonary aspergillosis, maternal exposure to mainstream CS increases AHR after acute intratracheal administration of Aspergillus fumigatus extract. However, the mechanism by which gestational CS induces allergic asthma is unclear. We now show for the first time that, compared with controls, mice exposed prenatally to secondhand CS exhibit increased lung inflammation (predominant infiltration by eosinophils and polymorphs), atopy, and airway resistance, and produce proinflammatory cytokines (IL-4, IL-5, IL-6, and IL-13, but not IL-2 or IFN-γ). These changes, which occur only after an allergen (A. fumigatus extract) treatment, are correlated with marked up-regulated lung expression of M1, M2, and M3 muscarinic receptors and phosphodiesterase (PDE)4D5 isozyme. Interestingly, the PDE4-selective inhibitor rolipram attenuates the increase in AHR, muscarinic receptors, and PDE4D5, but fails to down-regulate lung inflammation, Th2 cytokines, or serum IgE levels. Thus, the fetus is extraordinarily sensitive to CS, inducing allergic asthma after postnatal exposure to allergens. Although the increased AHR might reflect increased PDE4D5 and muscarinic receptor expression, the mechanisms underlying atopy and lung inflammation are unrelated to the PDE4 activity. Thus, PDE4 inhibitors might ease AHR, but are unlikely to attenuate lung inflammation and atopy associated with childhood allergic asthma.
Crystal-Induced Neutrophil Activation: XI. Implication and Novel Roles of Classical Protein Kinase C
Authors: Popa-Nita Oana , Proulx Sophie , Paré Guillaume , Rollet-Labelle Emmanuelle , Naccache Paul H.
Published: July 2009

Monosodium urate (MSU) crystals are among the most potent proinflammatory stimuli, and an innate immune inflammatory response to the crystal surface is involved in the pathology of gouty arthritis. Furthermore, MSU crystals have recently been identified as danger signals able to induce the maturation of dendritic cells. Release of the crystals into the joint cavity promotes an acute inflammation characterized by a massive infiltration of neutrophils that leads to tissue damage. Protein kinase C (PKC) represents a family of serine/threonine kinases that play central signaling roles in multiple cellular responses. This family of kinases is divided into three subfamilies based on second messenger requirements: conventional (or classical), novel, and atypical. Despite their role in signal transduction, very little is known about the involvement of the PKC family in the inflammatory reaction induced by MSU crystals. In the present study, we show that MSU crystals activate conventional PKC isoforms, and that this activation is necessary for the MSU crystal-induced degranulation and generation of a chemotactic activity in the supernatants of MSU crystal-stimulated human neutrophils. Evidence is also obtained that the tyrosine kinase Syk is a substrate of PKC and that the PKC-mediated serine phosphorylation of Syk is necessary to its interaction with the regulatory subunit of PI3K kinases (p85) and thus to the subsequent activation of these lipid kinases. These results suggest novel means of modulating neutrophil responses (through the specific regulation of PKC) during the acute phase of MSU crystal-induced inflammation.
The Trafficking Victims Protection Act: Has the Legislation Fallen Short of its Goals?
Authors: McReynold MaryAnne
Published: July 2009

This analysis examines the immigration status that the United States government affords to individuals who are willing to meet the requirements of the Victims of Trafficking and Violence Protection Act of 2000, commonly known as the Trafficking Victims Protection Act (TVPA). This article presents the legislative history of the TVPA with an emphasis on the factors that heighten the tension between the interests of trafficking victims and those of the government. Available immigration relief is not truly "relief" unless it is accessible to those who need it, that is, those for whom Congress designated this type of visa status. Likewise, legislation that designates an action as criminal is fruitless unless it provides for effective investigations and enforcement. As crucial as it is to punish and deter traffickers, the special nature of this crime necessitates that the victims, who are central to the role of law enforcement, receive ample protection. In conclusion, the author suggests seven policy recommendations to improve the government's ability to punish and deter human traffickers while protecting the victims of these crimes.
The Endangered Gray Wolf in Wyoming: Managing Wolf Populations after Endangered Species Act Delisting
Authors: Jones Bryant
Published: July 2009

For over sixty years the distinct howl of the gray wolf has been absent from the Northern Rocky Mountains. The U.S. government successfully exterminated the species from all but Minnesota by the 1930s. With the passage of the Endangered Species Act of 1973 the gray wolf was protected by law. A recovery plan was developed throughout the 1980s and implemented beginning in 1995. Since then, populations of gray wolves in three designated recovery areas consisting of Montana, Idaho, and Wyoming have increased annually. The U.S. Fish and Wildlife Service (USFWS) is considering delisting the gray wolf from the endangered list and has begun to devolve management to state governments. Idaho and Montana's recovery plans were approved by USFWS, but Wyoming's plan was rejected. To ensure state management of wolves is achieved, Wyoming should seriously consider implementing a program similar to those of Idaho and Montana and one that will be easily approved by the USFWS. This paper proposes that Wyoming consider several different ways to manage the wolf population, including: developing a new wolf recovery plan using a a diverse group of stakeholders; continuing to keep wolves protected under state protection; developing a comprehensive education program to inform citizens about gray wolves; continuing to utilize the Defenders of Wildlife compensation program to repay ranchers for livestock depredation losses; and leaving the definition of a breeding pair as an adult male and female raising two or more pups until December 31 of the respective year.
Fabricating the People: Politics and Administration in the Biopolitical State
Authors: Love Jeannine
Published: July 2009

No abstract available.
The Post-American World
Authors: Bhatti Imtiaz
Published: July 2009

No abstract available.
Cerebrospinal fluid of brain trauma patients inhibitsin vitroneuronal network function via NMDA receptors
Authors: Otto Frauke , Illes Sebastian , Opatz Jessica , Laryea Maurice , Theiss Stephan , Hartung Hans‐Peter , Schnitzler Alfons , Siebler Mario , Dihné Marcel
Published: July 2009

Neurological diseases frequently induce pathological changes of cerebrospinal fluid (CSF) that might secondarily influence brain activity, as the CSF–brain barrier is partially permeable. However, functional effects of CSF on neuronal network activity have not been specified to date. Here, we report that CSF specimens from patients with reduced Glasgow Coma Scale values caused by severe traumatic brain injury suppress synchronous activity of in vitro‐generated neuronal networks in comparison with controls. We present evidence that underlying mechanisms include increasedN‐methyl‐D‐aspartate receptor activity mediated by a CSF fraction containing elevated amino acid concentrations. These proof‐of‐principle data suggest that determining effects of CSF specimens on neuronal network activity might be of diagnostic value. Ann Neurol 2009;66:546–555
Synthesis and Characterization of New Liver Targeting 5‐Fluorouracil‐Cholic Acid Conjugates
Authors: Qian Shan , Wu Jian‐Bo , Wu Xiao‐Chun , Li Jie , Wu Yong
Published: July 2009

The objective of this work was to develop a liver‐specific antihepato carcinoma agent. A series of 5‐fluorouracil / cholic acid conjugates (5‐FU‐cholic acid conjugates) were prepared and tested for their chemical characteristics and bio‐distribution properties. The in‐vitro stability trial showed 5‐FU‐cholic acid conjugates could be completely hydrolyzed by heating at 70°C in an acidic solution, pH = 1, for 5 min. The fast and complete hydrolysis of these compounds could be compatible with a fast separation and analysis method to shorten the analysis time. The decomposition speeds of the 5‐FU‐cholic acid conjugates in different organs of mice at several time points after oral administration were evaluated by measuring the concentrations of regenerated 5‐FU in organ tissue. The results were compared with those of the controls, which was a group of mice orally taking 5‐FU. The concentrations of 5‐FU in mice liver tissue were remarkably increased after oral administration of the prodrugs, and were much larger than if only orally administered 5‐FU. The results suggested the feasibility to improve therapeutic efficiency of liver targeting treatments by using cholic acid as the vector of drugs.
Rhenium‐ and Manganese‐Catalyzed Insertion of Alkynes into a Carbon–Carbon Single Bond of Cyclic and Acyclic 1,3‐Dicarbonyl Compounds
Authors: Kuninobu Yoichiro , Kawata Atsushi , Nishi Mitsumi , Yudha S. Salprima , Chen Jingjin , Takai Kazuhiko
Published: July 2009

Treatment of alkynes with cyclic and acyclic 1,3‐dicarbonyl compounds in the presence of a catalytic amount of a rhenium or manganese complex gives ring‐expanded and carbon‐chain extension products, respectively. In these reactions, alkynes insert into a non‐strained carbon–carbon single bond of 1,3‐dicarbonyl compounds. The ring‐expansion reaction is also promoted by the addition of 4‐Å molecular sieves instead of a catalytic amount of an isocyanide.
Nanorobots: The Ultimate Wireless Self‐Propelled Sensing and Actuating Devices
Authors: Sánchez Samuel , Pumera Martin
Published: July 2009

Natural motor proteins, “bionanorobots,” have inspired researchers to develop artificial nanomachines (nanorobots) able to move autonomously by the conversion of chemical to mechanical energy. Such artificial nanorobots are self‐propelled by the electrochemical decomposition of the fuel (up to now, hydrogen peroxide). Several approaches have been developed to provide nanorobots with some functionality, such as for controlling their movement, increasing their power output, or transporting different cargo. In this Focus Review we will discuss the recent advances in nanorobots based on metallic nanowires, which can sense, deliver, and actuate in complex environments, looking towards real applications in the not‐too‐distant future.
The four cysteines ring motif in proteins
Authors: Zagari Adriana
Published: July 2009

Disulfide bonds play fundamental roles in proteins. This work is devoted to highly rare motifs containing disulfide bonds. A search for four cysteines, forming a 16‐atom membered ring (4CR) embodying two disulfide bonds, was carried out against all entries in the Protein Data Bank. Searching the crystallographic subset, only few protein molecules, all dimeric, were found to embody this peculiar structural feature, which establishes a covalent link between two different polypeptide chains. In contrast, in a peptide studied in solution by NMR, the four cysteines moiety includes only residues from one chain. A comparative analysis provided evidence for similarity and difference. It emerged that 4CR motif is highly rare and may serve to gain a specialized function. © 2009 Wiley Periodicals, Inc. Biopolymers 91: 1048–1055, 2009.

This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Design and validation of a pulsatile perfusion bioreactor for 3D high cell density cultures
Authors: Chouinard Julie A. , Gagnon Serge , Couture Marc G. , Lévesque Alain , Vermette Patrick
Published: July 2009

This study presents the design and validation of a pulsatile flow perfusion bioreactor able to provide a suitable environment for 3D high cell density cultures for tissue engineering applications. Our bioreactor system is mobile, does not require the use of traditional cell culture incubators and is easy to sterilize. It provides real‐time monitoring and stable control of pH, dissolved oxygen concentration, temperature, pressure, pulsation frequency, and flow rate. In this bioreactor system, cells are cultured in a gel within a chamber perfused by a culture medium fed by hollow fibers. Human umbilical vein endothelial cells (HUVEC) suspended in fibrin were found to be living, making connections and proliferating up to five to six times their initial seeding number after a 48‐h culture period. Cells were uniformly dispersed within the 14.40 mm × 17.46 mm × 6.35 mm chamber. Cells suspended in 6.35‐mm thick gels and cultured in a traditional CO2 incubator were found to be round and dead. In control experiments carried out in a traditional cell culture incubator, the scarcely found living cells were mostly on top of the gels, while cells cultured under perfusion bioreactor conditions were found to be alive and uniformly distributed across the gel. Biotechnol. Bioeng. 2009; 104: 1215–1223. © 2009 Wiley Periodicals, Inc.
Preparation of a super‐long two column chromatography system and its application in separating glycosylated puerarin
Authors: Zhu Shouchuang , Xu Haidong , Yu Cigang , Ding Juanfang , Chen Ting , Jiang Jierong , Dai Yijun , Liu Guiyou , Huang Guodong , Chai Nan , Jiang Xuhua , Yuan Sheng
Published: July 2009

Separation of Puerarin‐7‐O‐glucoside from its precursor, puerarin, using a common chromatography column packed with AB‐8 macroporous resin was unsuccessful. Therefore, in this study a 8 m super‐long flexible reinforced PVC column was externally added to the common column in order to improve the chromatography efficiency by increasing the number of theoretical plates. Both the PVC and common columns were separately packed with AB‐8 macroporous resin slurry. The packed PVC column was coiled after washing and stored until use. The microbial transformation mixture with puerarin‐7‐O‐glucoside and puerarin (250 mL) was loaded onto the common column, followed by washing with 2000 mL H2O. After attaching the coiled external PVC column to the common column, a linear gradient of 10–30% ethanol was applied to elute the target compound. Two peaks appeared: peak I contained puerarin‐7‐O‐glucoside at 97.9% purity and 88.1% recovery rate, and peak II was puerarin at 98.7% purity and 87.0% recovery rate. The use of the coiled external flexible reinforced PVC column avoided spatial restriction for long columns, which made it much more convenient for column packing and chromatography operations. Furthermore, this method eliminated the resin blockage problem caused by stationary water pressure in a rigid vertical long column. Using an external super‐long column, the PVC tube was connected with the common column only during elution, which avoided delay in time period during sample loading and column washes associated with the use of long external columns. Copyright © 2009 John Wiley & Sons, Ltd.
Fractionation of transgenic corn seed by dry and wet milling to recover recombinant collagen‐related proteins
Authors: Zhang Cheng , Glatz Charles E. , Fox Steven R. , Johnson Lawrence A.
Published: July 2009

Corn continues to be considered an attractive transgenic host for producing recombinant therapeutic and industrial proteins because of its potential for producing recombinant proteins at large volume and low cost as coproducts of corn seed‐based biorefining. Efforts to reduce production costs have been primarily devoted to increasing accumulation level, optimizing protein extraction conditions, and simplifying the purification. In the present work, we evaluated two grain fractionation methods, dry milling and wet milling, to enrich two recombinant collagen‐related proteins; thereby, reducing the amount and type of corn‐derived impurities in subsequent protein extraction and purification steps. The two proteins were a full‐length human recombinant collagen type I alpha 1(rCIα1) chain with telopeptides and peptide foldon to effect triple helix formation and a 44‐kDa rCIα1 fragment. For each, ∼60% of the rCIα1s in the seed was recovered in the dry‐milled germ‐rich fractions making up ca. 25% of the total kernel mass. For wet milling, ∼60% of each was recovered in three fractions accounting for 20–25% of the total kernel mass. The rCIα1s in the dry‐milled germ‐rich fractions were enriched three to six times compared with the whole corn kernel, whereas the rCIα1s were enriched 4–10 times in selected wet‐milled fractions. The recovered starch from wet milling was almost free of rCIα1. Therefore, it was possible to generate rCIα1‐enriched fractions by both dry and wet milling along with rCIα1‐free starch using wet milling. Because of its simplicity, the dry milling procedure could be accomplished on‐farm thus minimizing the risk of inadvertent release of viable transgenic seeds. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009
Chain gear design using artificial neural networks
Authors: Toktas Ihsan , Basak Hudayim
Published: July 2009

In this study, the analytical calculation and analysis for the data corresponding to these gears have been made to obtain alternative test and training data sets to be used at the artificial neural networks(ANNs) with the constraints and requirements for the design of chain gears of power and motion transmission mechanisms are determined. In the input layer, the constraints and requirement values(input power, number of revolution of the pinion, number of revolution of the gear and center distance) of chain gears are used while at the output layer chain code(i.e., the chain gear type and chain sequence number), specifying the functional and physical properties, is used. Then the network is tested with the test data. The analytical calculation results and ANN predictions are compared by using statistical error analyzing methods such as absolute fraction of variance(R2), root mean square error(RMSE), and mean error percentage(MEP) for the training and test data. The chain code has been determined by the ANN with an acceptable accuracy. It is concluded that ANNs can be used as an alternative method in chain gear design. © 2009 Wiley Periodicals, Inc. Comput Appl Eng Educ 20: 38–44, 2012
Deactivation of TEM‐1 β‐Lactamase Investigated by Isothermal Batch and Non‐Isothermal Continuous Enzyme Membrane Reactor Methods
Authors: Rogers Thomas A. , Daniel Roy M. , Bommarius Andreas S.
Published: July 2009

The thermal deactivation of TEM‐1 β‐lactamase was examined using two experimental techniques: a series of isothermal batch assays and a single, continuous, non‐isothermal assay in an enzyme membrane reactor (EMR). The isothermal batch‐mode technique was coupled with the three‐state “Equilibrium Model” of enzyme deactivation, while the results of the EMR experiment were fitted to a four‐state “molten globule model”. The two methods both led to the conclusions that the thermal deactivation of TEM‐1 β‐lactamase does not follow the Lumry‐Eyring model and that the Teq of the enzyme (the point at which active and inactive states are present in equal amounts due to thermodynamic equilibrium) is at least 10 °C from the Tm (melting temperature), contrary to the idea that the true temperature optimum of a biocatalyst is necessarily close to the melting temperature.
Molecular Complexes of Simple Anions with Electron‐Deficient Arenes: Spectroscopic Evidence for Two Types of Structural Motifs for Anion–Arene Interactions
Authors: Chiavarino Barbara , Crestoni Maria Elisa , Fornarini Simonetta , Lanucara Francesco , Lemaire Joel , Maître Philippe , Scuderi Debora
Published: July 2009

Anion–π interactions between a π‐acidic aromatic system and an anion are gaining increasing recognition in chemistry and biology. Herein, the binding features of an electron‐deficient aromatic system (1,3,5‐trinitrobenzene (TNB)) and selected anions (OH−, Br−, and I−) are examined in the gas phase by using the combined information derived from collision‐induced dissociation experiments at variable energy, infrared multiple‐photon dissociation spectroscopy, and quantum chemical calculations. We provide spectroscopic evidence for two different structural motifs of anion–arene complexes depending on the nature of the anion. The TNB–OR− complexes (R=H, or alkyl groups which were studied earlier) adopt an anionic σ‐complex structure whereby RO− attacks the aromatic ring with covalent bond formation, and develops a tetrahedral ring carbon bound to H and OR. The halide complexes rather conform to a structure in which the TNB moiety is hardly altered, and the halogen is placed on an unsubstituted carbon atom over the periphery of the ring at a C–X distance that is appreciably longer than a typical covalent bond length. The ensuing structural motif, previously characterized in the solid state and named weak σ interaction, is now confirmed by an IR spectroscopic assay in the gas phase, in which the sampled species are unperturbed by crystal packing or solvation effects.
Electrochemical Characterisation of 6‐Iodomaltose, 6′‐Iodomaltose and 6‐Iodomaltotriose on a Silver Cathode and Their One‐Pot Electrochemical Dimerisation to New Mixed O/C Maltotetraose and Maltohexaose Mimics
Authors: Alberti Angelo , Macciantelli Dante , Naggi Annamaria , Urso Elena , Torri Giangiacomo , Vismara Elena
Published: July 2009

The electrochemical reduction on silver of peracetylated 6‐iodo‐6‐deoxy‐β‐maltose (2), 6‐iodo‐6‐deoxy‐β‐maltotriose (3) and 6′‐iodo‐6′‐deoxy‐β‐maltose (4) has been investigated by cyclic voltammetry and performed on a preparative scale, according to the stoichiometry, CH2I(2–4)+e−→CH2.+I−. In agreement with the preparative electrolysis results, cyclic voltammetry showed different profiles for the reducing terminal‐iodinated 2 and 3 and for the non‐reducing terminal‐iodinated 4. Compounds 2 and 3 partly dimerised to maltotetraoses mimics 7 (6,6‐dimer) and 8 (5′,5′‐dimer) in 38 % overall yield and to maltohexaose mimics 12 (6,6‐dimer) and 13 (5′,5′‐dimer) in 30 % overall yield, respectively. Compounds 7 and 12 came from the dimerisation of CH2., primary radicals at C‐6, which could also abstract H‐5′, becoming CH3 and generating the C‐5′ quaternary radicals that dimerised in 8 and 13, respectively. These products were accompanied by the maltose derivatives 9, 10 and 11 a/b in 42 % overall yield and by the maltotriose derivatives 14, 15 and 16 in 48 % overall yield, respectively. Compounds 9, 14 and 10, 15 came from CH2. disproportionation to CH3 and CH2C, respectively (exocyclic double bond C‐6/C‐5). Compounds 11 a/b and 16 came from C‐5′ radical reduction, followed by acetate anion elimination (double bonds C‐6′/C‐5′ and C‐5′/C‐4′). In turn, 4 afforded only the 6′,6′‐dimer maltotetraose mimic 17 in 60 % yield, accompanied by the reduced maltose 18 in 20 % yield, in which the starting CH2I became CH3. Compounds 7, 8, 12, 13 and 17 belong to a class of mixed O/C malto‐mimic oligosaccharides wherein an unnatural CC bond between two saccharide units increases metabolic stability compared to their O‐analogues and modulates the sugar chain conformational flexibility, a fundamental parameter in determining protein–carbohydrate binding. Direct and spin‐trapping EPR studies substantiated the radical‐based nature of the dimerisation processes and allowed the identification of some of the paramagnetic species involved.
Prominent system of RFamide immunoreactive neurons in the rhopalia of box jellyfish (Cnidaria: Cubozoa)
Authors: Parkefelt Linda , Ekström Peter
Published: July 2009

The four visual sensory structures of a cubomedusa, the rhopalia, display a surprisingly elaborate organization by containing two lens eyes and four bilaterally paired pigment cup eyes. Peptides containing the peptide sequence Arg‐Phe‐NH2 (RFamide) occur in close association with visual structures of cnidarians, including the rhopalia and rhopalial stalk of cubomedusae, suggesting that RFamide functions as a neuronal marker for certain parts of the visual system of medusae. Using immunofluorescence we give a detailed description of the organization of the RFamide‐immunoreactive (ir) nervous system in the rhopalia and rhopalial stalk of the cubomedusae Tripedalia cystophora and Carybdea marsupialis. The bilaterally symmetric RFamide‐ir nervous system contains four cell groups and three morphologically different cell types. Neurites spread throughout the rhopalia and occur in close vicinity of the pigment cup eyes and the lower lens eye. Two commissures connect the two sides of the system and neurites of one rhopalial cell group extend into the rhopalial stalk. The RFamide‐ir nervous system in the rhopalia of cubomedusae is more widespread and comprises more cells than earlier discerned. We suggest that the system might not only integrate visual input but also signals from other senses. One of the RFamide‐ir cell groups is favorably situated to represent pacemaker neurons that set the swimming rhythm of the medusa. J. Comp. Neurol. 516:157–165, 2009. © 2009 Wiley‐Liss, Inc.
Effects of Fullerenes on Phospholipid Membranes: A Langmuir Monolayer Study
Authors: Wang Zhining , Yang Shihe
Published: July 2009

We investigate two‐component Langmuir monolayers of dipalmitoylphosphatidylcholine (DPPC)/C60 by recording surface pressure/area (π/A) and surface potential/area (ΔV/A) isotherms and by direct Brewster angle microscopy (BAM) imaging. Atomic force microscopy (AFM) is employed to study morphologies of the mixed monolayers transferred to a solid substrate by the Langmuir–Blodgett technique. C60 is shown to have little influence on isotherms of the DPPC/C60 monolayers even at a molar fraction as high as XC60=0.3. The elastic modulus (${C_{\rm{s}}^{ - 1} }$) versus π curves of the DPPC/C60 monolayers almost overlay each other, as well as that of pure DPPC, that is, the elasticities of pure DPPC monolayers and DPPC/C60 monolayers are remarkably similar. AFM studies reveal that fullerene flocs form at low surface pressures (π≤15 mN m−1), are gradually disaggregated and dispersed in the DPPC monolayer with increasing surface pressure up to 35 mN m−1, and are then progressively squeezed out to form protruded islands as the surface pressure increases up to 65 mN m−1. Our work provides experimental support to the computational result that C60 can dissolve in lipid bilayers without significantly compromising their mechanical properties, a finding which has important implications for the toxicity and development of drug vehicles from fullerene materials.
DIRT—danger ideation reduction therapy for obsessive–compulsive washers: a comprehensive guide to treatment
Authors: O'Connor Kieron
Published: July 2009

Danger ideation reduction therapy (DIRT) for obsessive compulsive disorder (OCD) is a new intervention focusing on providing corrective information, and is the subject of a new comprehensive guide to treatment for compulsive washing. The components of DIRT are well presented in this manual‐based treatment and the documentation includes dialogues, filmed interviews with workers in dangerous occupations, and fact sheets to persuade the client to exchange beliefs about danger for beliefs about safety. The book is well organized and user friendly. Clinical trials have shown DIRT to be an effective treatment. Although DIRT as a stand alone therapy seems to offer some advantages over conventional CBT, it may function currently more as an adjunct to help cognitive restructuring. DIRT certainly encourages us to rethink some assumptions about the use of corrective information in treating OCD. Copyright © 2009 John Wiley & Sons, Ltd.

Key Practitioner Message:

• Danger ideation therapy is principally a cognitive approach.

• Corrective information may help in the treatment of OCD for washing.

• The application of DIRT in other types of OCD and symbolic contamination remains uncertain.
Preparation, Magnetic and Structural Study on Oxido‐Bridged Diiron(III) Complexes with Open‐Chain Tetrapyrrolic 2,2′‐Bidipyrrin Ligands
Authors: Bröring Martin , Köhler Silke , Ostapowicz Thomas , Funk Markus , Pietzonka Clemens
Published: July 2009

Four (μ‐oxido)diiron(III) complexes of differently alkyl‐substituted 2,2′‐bidipyrrin ligands [(L)Fe]2O have been prepared by a one‐pot approach from the respectively substituted 2,2′‐bipyrroledialdehydes and 3,4‐dialkylpyrroles, and from a suitable source of trivalent iron, under alkaline conditions. Four single‐crystal X‐ray diffraction studies were undertaken on three of the new compounds as different solvates. The iron atoms are five‐coordinate in all cases, and the observed Fe–N and Fe–O distances are in the range of 2.024–2.082 Å and 1.761–1.818 Å, respectively. These bonds are (porphyrinato)iron‐like, typical for high spin iron(III) complexes, and clearly distinct from those observed for the respective mononuclear (chlorido)‐, (bromido)‐ and (iodido)iron(III)–2,2′‐bidipyrrins, which contain a central intermediate spin iron(III) ion in the solid state. All complexes contain two helically distorted tetrapyrrolic ligands with the same sense of helicity, but pack quite differently from one case to the other. A cleft is present on one side of the connecting oxygen atom, which is occupied either by a self‐complementary second molecule of the complex itself, or by a small molecule (dichloromethane, or pyrrole with N–H···O bond). The Fe–O‐Fe subunits are bent and can be grouped with respect to the Fe–O–Fe bond angle range of either 153.91–156.89° or 131.89–132.97°. All new compounds were investigated by analytical, spectroscopic and magnetic means and found weakly paramagnetic and dynamic with respect to helix inversion at ambient temperature in solution. SQUID magnetometry revealed antiferromagnetically coupled high spin iron(III) species with exchange coupling constants of J = –111 to –122 cm–1. The exchange coupling appears independent from the Fe–O–Fe angle as described earlier for related porphyrinoid and salen‐type (μ‐oxido)diiron(III) species. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Silylene/Oxazolidinone Double‐Locked Sialic Acid Building Blocks for Efficient Sialylation Reactions in Dichloromethane
Authors: Hanashima Shinya , Sato Ken‐ichi , Ito Yukishige , Yamaguchi Yoshiki
Published: July 2009

We describe efficient sialylation reactions in CH2Cl2 with the use of silylene/oxazolidinone double‐locked sialic acid building blocks. The building blocks were synthesized from 4,5‐oxazolidinone‐protected phenylthiosialoside. In sialylation reactions towards primary and relatively reactive secondary hydroxy groups on the galactosides, the double‐locked building blocks provided desired coupling products in good yields with excellent α‐selectivities. In the sialylation reaction with the C3‐OH of the galactoside, the double‐locked building blocks expressed significantly better α‐selectivity in comparison with the results obtained by using the oxazolidinone‐locked building block. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Synthesis and Supramolecular Properties of a Novel Octaphosphonate Porphyrin
Authors: Bhosale Sheshanath V. , Kalyankar Mohan B. , Langford Steven J. , Bhosale Sidhanath V. , Oliver Ruth F.
Published: July 2009

Two complementary routes were developed for preparing novel octaphosphonate porphyrins. The use of protected/deprotected phosphonate‐substituted precursors in the rational synthesis gave an overall yield 16 %. A more streamlined synthetic path gave 21 % overall yield of the target molecule. Octaphosphonate porphyrin possesses promising properties in supramolecular aggregate formation with cyclam. Cofacial reversible self‐assembly of a meso‐substituted octaphosphonate porphyrin with cyclam yields micrometer‐long nanowires with a height of about 1–1.5 nm. The resulting wires were characterized by UV/Vis absorption, emission and atomic force microscopy and transmission electron microscopy.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)
Combining capillary electrophoresis with laser‐induced fluorescence detection for the analysis of Escherichia coli lysates
Authors: Wu Shu‐Feng , Chiu Tai‐Chia , Ho Wei‐Li , Chang Huan‐Tsung
Published: July 2009

With the goal of improving water quality control, in this study we combined CE‐LIF for the analysis of Escherichia coli lysates under discontinuous conditions. Prior to injecting a large‐volume protein sample, a plug of 0.2% w/v SDS was injected into the capillary filled with 2.0 M Tris‐borate (TB) solution (pH 10.3). During the courses of the process stacking, proteins migrated against the electroosmotic flow (EOF) and entered a 1.7% w/v poly(ethylene oxide) solution that has been prepared in 200 mM TB (pH 9.0). The stacked proteins were then separated through sieving and then detected at the cathodic end. The use of TB solutions containing 0.01% w/v poly(ethylene oxide) was essential for the preparation of the protein samples and E. coli lysates to minimize the extent of protein adsorption on the capillary wall. Under the optimized CE‐LIF conditions, we detected β‐Galactosidase with and without concentration at levels as low as 0.23 and 7.52 nM, respectively. Our approach allowed the detection of 3×102 E. coli cells based on the characteristic peaks of its lysates; in addition, we could detect the presence of 20 E. coli cells in a 50 mL sample of pond water within 24 h. In terms of the analyte migration time, the relative standard deviation of this CE‐LIF method was less than 1.3%. We also extended the practicality of this technique by applying it to the separation of mixtures of E. coli, Enterobacter aerogenes, and Salmonella enterica.