bluuebunny/crossref_metadata_2025 huggingface dataset:
Experiences in Qualification, Installation, and Operation of Wet Conductive Connectors for TOGI
Authors: Dahl P.R. , Kjoelberg S.A. , Arnesen Kjell
Published: March 2009

The TOGI subsea template was the first true diverless system relying on wetmateable electrical connectors of conductive type. The process of development, qualification, purchase and installation of the connectors is described, problems that arose and how they were solved. 69 wet connectors have been inoperation for more than two years, and no major failures that influence gasproduction from the subsea station have occurred.

A general test programme and specification for "wet" conductiveconnectors was developed and refined. During the fabrication and test periodseveral failures of the connectors were discovered and corrected. Qualitycontrol and inspection from Company during fabrication is of utmostimportance.

During installation problems of hydroxide and carbonate layers on metallicsurfaces due to the cathodic protection system were solved.

Due to the serious operational consequences of failures in electricalconnectors, operators should establish inhouse expertise in this field.

Introduction

In the early days of subsea electrohydraulic control systems conductiveconnectors were tried with little success. Reliability of these connectors wastoo low, and the industry soon turned to using inductive couplers. In principlean inductive coupler can be regarded as a transformer cut into two halves. Itis thus obviously much easier to seal off from seawater contact the front endof such a coupler than the front end of a conductive one. However, at the backend the coupler to cable connection, the same problems are raised as forconductive connectors. But designs have been made that solve these problems. Anumber of subsea developments were made using inductive couplers, and thecouplers proved to service in great numbers for many years without problems. Inaddition the inductive coupler can have more advantages than just reliability, it serves as galvanic insulation, voltage can be transformed across thecoupler, mating operations can be made very simple, and the coupler can bedesigned in a network such that it can be left in unmated position with poweron.
Quick Disconnectable Catenary Electrical Umbilical for Bruce Field Development
Authors: Chaudhuri Jay
Published: March 2009

The paper outlines the novel design features of the high voltage (11 kV)power and control/signal composite umbilical linking the BP BRUCE DrillingPlatform and the semi-submersible Utility Support Vessel (USV). The catenaryumbilical supplies the Drilling Platform's electrical power requirements andprovides the essential signal/control instrument link between the platform andthe control centre on the USV.

The composite power/signal umbilical is equipped with sub-sea ratedelectrical connectors and quick disconnect couplings at the USV interface. Thequick disconnect facility is the first of its kind to be employed for powerumbilical disconnection in a North Sea project.

The catenary umbilical and its components have been designed for the100-year extreme wave, current and associated USV motions. The design of theumbilical, associated electrical connectors and deployment/recovery systemprovide for easy relocation and adaptation to other platforms when BRUCE fieldrequirements for platform drilling have been completed.

Introduction

The Bruce Field, discovered in 1974, is the largest gas field underdevelopment in the UK North Sea, containing estimated reserves of 2.6 TCF ofsales gas and 220 MMB of condensate and oil. Located in the northern North Sea400 km north east of Aberdeen, the Bruce Field occupies an area of 75 squarekilometres spanning licence blocks 9/8a, 9/9a and 9/9b. Co-venturers in theProject are BP Exploration (Operator), Elf, Hamilton, Total and Ultramar.

With an estimated development cost of £1.5 billion, the Bruce Development isthe largest current oil and gas project in the UK. First sales gas is scheduledfor delivery in October 1993. Peak production will be reached in 1994 withsales to British Gas of some 480 million cubic feet per day and sales to CorbyPower Project of some 50 million cubic feet per day. Liquids production willpeak at 80,000 b/d. The ultimate field life is projected to be approximately 25years. Once on stream the Bruce Field will provide nearly 10% of the UK's gasrequirements in the 1990's.
Recovery and Laying Hybrid Pipelines in Deep Water
Authors: Scherer I.M.Q. , Teixeira M.J.B. , Espinasse P.F.
Published: March 2009

In order to develop three new deep water fields using the FPS that haveproved technically efficient and cost effective over the last 16 years, Petrobras has had to find new ways of installing export pipelines for existingdevelopment in water depth of up to 725 meters using economically attractiveand technically sound methods.

The hybrid rigid/flexible combination export pipeline method was engineeredand successfully put into practice in less than 8 months for the deepest gasexport line ever installed.

After the successful installation of the 8 inch gas line in 625 meters ofwater depth on the Marlim field, 5 other such pipelines are to be installed in1993, ranging from 12 inch in 340 meters to 8 inch in 725 meters waterdepth.

This paper presents the various phases of engineering, fabrication andinstallation consisting in recovering a prelaid steel pipe in a "J"configuration to add in the final segments of flexible flowline and riser withany above surface connection.

The method was based in using available vessels and standard tooling, toavoid costs and risks linked to the development of new deep water connectiontools and technology.

The operational and economical benefits of the method are addressed as wellas its potential evolutions.

Introduction

Petrobras has become over the last 16 years, the leader in deep waterproduction technology, starting with the development of the Enchova field in100/150 meters water depth back in 1977 to the present Marlim/Barracuda/Bijupira and Albacora developments in the 600/900 meters water depth range. Such increase in water depth has not been attained without substantialinnovative thinking, fast decision making and a certain credence in applicationof new technology. The true pioneering spirit is alive and well at Petrobrasand has proved efficient over the years.

Stepping out the continental plateau in water depths far and beyond diveraccess, further and further away from existing production and gatheringnetworks has required innovative thinking to remain cost efficient, pushingexisting and proven technology to new frontiers.
Complement Factor H, a Marker of Self Protects against Experimental Autoimmune Encephalomyelitis
Authors: Griffiths Mark R. , Neal Jim W. , Fontaine Marc , Das Trina , Gasque Philippe
Published: March 2009

The CNS innate immune response is a “double-edged sword” representing a fine balance between protective antipathogen responses and detrimental neurocytotoxic effects. Hence, it is important to identify the key regulatory mechanisms involved in the control of CNS innate immunity and which could be harnessed to explore novel therapeutic avenues. In analogy to the newly described neuroimmune regulatory proteins also known as “don’t eat me” signals (CD200, CD47, CD22, fractalkine, semaphorins), we herein identify the key role of complement regulator factor H (fH) in controlling neuroinflammation initiated in an acute mouse model of Ab-dependent experimental autoimmune encephalomyelitis. Mouse fH was found to be abundantly expressed by primary cultured neurons and neuronal cell lines (N1E115 and Neuro2a) at a level comparable to BV2 microglia and CLTT astrocytes. Mouse neurons expressed other complement regulators crry and low levels of CD55. In the brain, the expression of fH was localized to neuronal bodies and axons, endothelial cells, microglia but not oligodendrocytes and myelin sheaths and was dramatically reduced in inflammatory experimental autoimmune encephalomyelitis settings. When exogenous human fH was administered to disease Ab-dependent experimental autoimmune encephalomyelitis animals, there was a significant decrease in clinical score, inflammation, and demyelination, as compared with PBS-injected animals. We found that the accumulation of human fH in the brain parenchyma protected neurons from complement opsonization, axonal injury, and leukocyte infiltration. Our data argue for a key regulatory activity of fH in neuroprotection and provide novel therapeutic avenues for CNS chronic inflammatory diseases.
B Cell Proliferation, Somatic Hypermutation, Class Switch Recombination, and Autoantibody Production in Ectopic Lymphoid Tissue in Murine Lupus
Authors: Nacionales Dina C. , Weinstein Jason S. , Yan Xiao-Jie , Albesiano Emilia , Lee Pui Y. , Kelly-Scumpia Kindra M. , Lyons Robert , Satoh Minoru , Chiorazzi Nicholas , Reeves Westley H.
Published: March 2009

Intraperitoneal exposure of nonautoimmune mice to 2,6,10,14-tetramethylpentadecane (TMPD) causes lupus and the formation of ectopic lymphoid tissue. Although associated with humoral autoimmunity, it is not known whether Ab responses develop within ectopic lymphoid tissue or if B cells only secondarily migrate there. We show that ectopic lymphoid tissue induced by TMPD not only resembles secondary lymphoid tissue morphologically, but it also displays characteristics of germinal center reactions. Proliferating T and B lymphocytes were found within ectopic lymphoid tissue, activation-induced cytidine deaminase was expressed, and class-switched B cells were present. The presence of circular DNA intermediates, a hallmark of active class switch recombination, suggested that class switching occurs within the ectopic lymphoid tissue. Individual collections of ectopic lymphoid tissue (“lipogranulomas”) from the same mouse contained different B cell repertoires, consistent with local germinal center-like reactions. Class-switched anti-RNP autoantibody-producing cells were also found in the lipogranulomas. Somatic hypermutation in the lipogranulomas was T cell-dependent, as was the production of isotype-switched anti-Sm/RNP autoantibodies. Thus, ectopic lymphoid tissue induced by TMPD recapitulates many of the functional characteristics of secondary lymphoid tissue and contains autoantibody-secreting cells, which may escape from normal censoring mechanisms in this location.
Recall Responses by Helpless Memory CD8+ T Cells Are Restricted by the Up-Regulation of PD-1
Authors: Fuse Shinichiro , Tsai Ching-Yi , Molloy Michael J. , Allie S. Rameeza , Zhang Weijun , Yagita Hideo , Usherwood Edward J.
Published: March 2009

CD4 help is crucial for memory CD8+ T cell development, yet the mechanisms of CD4 help and why (CD4) helpless memory CD8+ T cells elicit poor recall responses are currently not well understood. In this study we investigated these questions using an in vivo acute virus infection model. We show herein that CD4 help during priming is required for memory CD8+ T cell differentiation, and that stimulation of CD40 during priming rescues the helpless defects in the absence of CD4+ T cells. The defective recall response by helpless memory cells did not correlate with the amount of cell death and was independent of TRAIL. However, helpless memory cells excessively up-regulated the inhibitory receptor PD-1 (programmed cell death-1), and PD-1 blockade enhanced the recall response of helpless memory cells. Furthermore, providing IL-2 signaling in vivo during the recall response reduced PD-1 expression and rescued the recall response of helpless memory cells. Our study identifies molecular pathways involved in CD4 help for memory CD8+ T cell generation that are independent of TRAIL, and it provides therapeutic implications that helpless memory cell function can be restored at multiple stages through various immunological interventions.
Characterization of an Immediate Splenic Precursor of CD8+ Dendritic Cells Capable of Inducing Antiviral T Cell Responses
Authors: Bedoui Sammy , Prato Sandro , Mintern Justine , Gebhardt Thomas , Zhan Yifan , Lew Andrew M. , Heath William R. , Villadangos José A. , Segura Elodie
Published: March 2009

Mouse spleens contain three major dendritic cell (DC) populations: plasmacytoid DC, conventional CD8+CD24+ DC (CD8+ DC), and conventional CD8−CD24− DC (CD8− DC). We have previously shown that CD8+ DC are the major cross-presenting subtype in vivo and are the main inducers of antiviral cytotoxic T lymphocyte responses. Here we show that after depletion of CD8+ DC, the only DC capable of viral Ag presentation was a small subset that expresses CD24 but not CD8. This CD8−CD24+ DC population is greatly expanded in mice treated with the DC growth factor FMS-like tyrosine kinase 3 ligand. The CD8−CD24+ DC represent an immediate precursor of CD8+ DC, as demonstrated by their expression pattern of characteristic markers of CD8+ DC, their capacity to cross-present in vitro, and their conversion into CD8+ DC upon adoptive transfer into recipient mice. Accordingly, the lifespan of transferred CD8−CD24+ DC in vivo was greatly enhanced as compared with terminally differentiated CD8+ DC. Moreover, in a vaccination protocol, CD8−CD24+ DC induced stronger T cell responses and accelerated viral clearance of HSV-1 compared with CD8+ DC. Our results demonstrate that the ability to cross-present first appears in an immediate precursor population of CD8+ DC that does not yet express CD8. The enhanced capacity of CD8−CD24+ DC to induce immune responses upon adoptive transfer makes them an attractive novel tool for DC-based immunotherapies.
PTPN22 Deficiency Cooperates with the CD45 E613R Allele to Break Tolerance on a Non-Autoimmune Background
Authors: Zikherman Julie , Hermiston Michelle , Steiner David , Hasegawa Kiminori , Chan Andrew , Weiss Arthur
Published: March 2009

Pep and CD45 are tyrosine phosphatases whose targets include the Src-family kinases, critical mediators of Ag receptor signaling. A polymorphism in PTPN22, the gene that encodes the human Pep orthologue Lyp, confers susceptibility to multiple human autoimmune diseases in the context of complex genetic backgrounds. However, the functional significance of the R620W risk allele is not clear. We report that misexpression of wild-type or R620W Pep/Lyp in Jurkat cells, in the context of its binding partner Csk, unmasks the risk allele as a hypomorph. It has been shown previously that although Pep-deficient mice on the B6 background have hyperresponsive memory T cells, autoimmunity does not develop. Mice containing a point mutation in the CD45 juxtamembrane wedge domain (E613R) develop a B cell-driven, lupus-like disease on the mixed 129/B6 background, but not on the B6 background. We studied the ability of Pep deficiency to act as a genetic modifier of the CD45 E613R mutation on the nonautoimmune B6 background to understand how complex susceptibility loci might interact in autoimmunity. In this study we report that double mutant mice develop a lupus-like disease as well as lymphadenopathy, polyclonal lymphocyte activation, and accelerated memory T cell formation. Following Ag receptor stimulation, peripheral B cells in the double mutant mice phenocopy hyperresponsive CD45 E613R B cells, whereas peripheral T cells respond like Pep−/− T cells. These studies suggest that Pep−/− T cells in the context of a susceptible microenvironment can drive hyperresponsive CD45 E613R B cells to break tolerance.
Signal Transduction Inhibition of APCs Diminishes Th17 and Th1 Responses in Experimental Autoimmune Encephalomyelitis
Authors: Skarica Mario , Wang Tianhong , McCadden Erin , Kardian David , Calabresi Peter A. , Small Donald , Whartenby Katharine A.
Published: March 2009

IL-17- and IFN-γ-secreting T cells play an important role in autoimmune responses in multiple sclerosis and the model system experimental autoimmune encephalomyelitis (EAE). Dendritic cells (DCs) in the periphery and microglia in the CNS are responsible for cytokine polarization and expansion of this T cell subset. Our results indicate that in vivo administration of a signal transduction inhibitor that targets DCs to mice with EAE led to a decrease in CNS infiltration of pathogenic Ag-specific T cells. Since this approach does not target T cells directly, we assessed the effects on the APCs that are involved in generating the T cell responses. Since in EAE and multiple sclerosis, both microglia and peripheral DCs are likely to contribute to disease, we utilized a bone marrow chimera system to distinguish between these two populations. These studies show that peripheral DCs are the primary target but that microglia are also modestly affected by CEP-701, as numbers and activation states of the cells in the CNS are decreased after therapy. Our results also showed a decrease in secretion of TNF-α, IL-6, and IL-23 by DCs as well as a decrease in expression of costimulatory molecules. We further determined that levels of phospho-Stat1, Stat3, Stat5, and NF-κB, which are signaling molecules that have been implicated in these pathways, were decreased. Thus, use of this class of signal transduction inhibitors may represent a novel method to treat autoimmunity by dampening the autoreactive polarizing condition driven by DCs.
Advanced Intercross Line Mapping Suggests That Ncf1 (Ean6) Regulates Severity in an Animal Model of Guillain-Barré Syndrome
Authors: Huberle Alexander , Beyeen Amennai Daniel , Öckinger Johan , Ayturan Miriam , Jagodic Maja , de Graaf Katrien L. , Fissolo Nicolas , Marta Monica , Olofsson Peter , Hultqvist Malin , Holmdahl Rikard , Olsson Tomas , Weissert Robert
Published: March 2009

We here present the first genetic fine mapping of experimental autoimmune neuritis (EAN), the animal model of Guillain-Barré syndrome, in a rat advanced intercross line. We identified and refined a total of five quantitative trait loci on rat chromosomes 4, 10, and 12 (RNO4, RNO10, RNO12), showing linkage to splenic IFN-γ secretion and disease severity. All quantitative trait loci were shared with other models of complex inflammatory diseases. The quantitative trait locus showing strongest linkage to clinical disease was Ean6 and spans 4.3 Mb on RNO12, harboring the neutrophil cytosolic factor 1 (Ncf1) among other genes. Polymorphisms in Ncf1, a member of the NADPH oxidase complex, have been associated with disease regulation in experimental arthritis and encephalomyelitis. We therefore tested the Ncf1 pathway by treating rats with a NADPH oxidase complex activator and ameliorated EAN compared the oil-treated control group. By proving the therapeutic effect of stimulating the NADPH oxidase complex, our data strongly suggest the first identification of a gene regulating peripheral nervous system inflammation. Taken together with previous reports, our findings suggest a general role of Ncf1 and oxidative burst in pathogenesis of experimental autoimmune animal models.
Nitrated α-Synuclein-Induced Alterations in Microglial Immunity Are Regulated by CD4+ T Cell Subsets
Authors: Reynolds Ashley D. , Stone David K. , Mosley R. Lee , Gendelman Howard E.
Published: March 2009

Microglial inflammatory neuroregulatory activities affect the tempo of nigrostriatal degeneration during Parkinson’s disease (PD). Such activities are induced, in part, by misfolded, nitrated α-synuclein (N-α-syn) within Lewy bodies released from dying or dead dopaminergic neurons. Such pathobiological events initiate innate and adaptive immune responses affecting neurodegeneration. We posit that the neurobiological activities of activated microglia are affected by cell-protein and cell-cell contacts, in that microglial interactions with N-α-syn and CD4+ T cells substantively alter the microglial proteome. This leads to alterations in cell homeostatic functions and disease. CD4+CD25+ regulatory T cells suppress N-α-syn microglial-induced reactive oxygen species and NF-κB activation by modulating redox-active enzymes, cell migration, phagocytosis, and bioenergetic protein expression and cell function. In contrast, CD4+CD25− effector T cells exacerbate microglial inflammation and induce putative neurotoxic responses. These data support the importance of adaptive immunity in the regulation of Parkinson’s disease-associated microglial inflammation.
Is there a trade‐off between fertility and longevity? A comparative study of women from three large historical databases accounting for mortality selection
Authors: Gagnon Alain , Smith Ken R. , Tremblay Marc , Vézina Hélène , Paré Paul‐Philippe , Desjardins Bertrand
Published: March 2009

Frontier populations provide exceptional opportunities to test the hypothesis of a trade‐off between fertility and longevity. In such populations, mechanisms favoring reproduction usually find fertile ground, and if these mechanisms reduce longevity, demographers should observe higher postreproductive mortality among highly fertile women. We test this hypothesis using complete female reproductive histories from three large demographic databases: the Registre de la population du Québec ancien (Université de Montréal), which covers the first centuries of settlement in Quebec; the BALSAC database (Université du Québec à Chicoutimi), including comprehensive records for the Saguenay‐Lac‐St‐Jean (SLSJ) in Quebec in the nineteenth and twentieth centuries; and the Utah Population Database (University of Utah), including all individuals who experienced a vital event on the Mormon Trail and their descendants. Together, the three samples allow for comparisons over time and space, and represent one of the largest set of natural fertility cohorts used to simultaneously assess reproduction and longevity. Using survival analyses, we found a negative influence of parity and a positive influence of age at last child on postreproductive survival in the three populations, as well as a significant interaction between these two variables. The effect sizes of all these parameters were remarkably similar in the three samples. However, we found little evidence that early fertility affects postreproductive survival. The use of Heckman's procedure assessing the impact of mortality selection during reproductive ages did not appreciably alter these results. We conclude our empirical investigation by discussing the advantages of comparative approaches. Am. J. Hum. Biol., 2009. © 2009 Wiley‐Liss, Inc.
Sequence variants on chromosome 9p21.3 confer risk for atherosclerotic stroke
Authors: Gschwendtner Andreas , Bevan Steve , Cole John W. , Plourde Anna , Matarin Mar , Ross‐Adams Helen , Meitinger Thomas , Wichmann Erich , Mitchell Braxton D. , Furie Karen , Slowik Agnieszka , Rich Stephen S. , Syme Paul D. , MacLeod Mary J. , Meschia James F. , Rosand Jonathan , Kittner Steve J. , Markus Hugh S. , Müller‐Myhsok Bertram , Dichgans Martin
Published: March 2009

Objective

Recent studies have identified a major locus for risk for coronary artery disease and myocardial infarction on chromosome 9p21.3. Stroke, in particular, ischemic stroke caused by atherosclerotic disease, shares common mechanisms with myocardial infarction. We investigated whether the 9p21 region contributes to ischemic stroke risk.

Methods

In an initial screen, 15 single nucleotide polymorphisms (SNPs) covering the critical genetic interval on 9p21 were genotyped in samples from Southern Germany (1,090 cases, 1,244 control subjects) and the United Kingdom (758 cases, 872 control subjects, 3 SNPs). SNPs significantly associated with ischemic stroke or individual stroke subtypes in either of the screening samples were subsequently genotyped in 2,528 additional cases and 2,189 additional control subjects from Europe and North America.

Results

Genotyping of the screening samples demonstrated associations between seven SNPs and atherosclerotic stroke (all p < 0.05). Analysis of the full sample confirmed associations between six SNPs and atherosclerotic stroke in multivariate analyses controlling for demographic variables, coronary artery disease, myocardial infarction, and vascular risk factors (all p < 0.05). The odds ratios for the lead SNP (rs1537378‐C) were similar in the various subsamples with a pooled odds ratio of 1.21 (95% confidence interval, 1.07–1.37) under both fixed‐ and random‐effects models (p = 0.002). The point estimate for the population attributable risk is 20.1% for atherosclerotic stroke.

Interpretation

The chromosome 9p21.3 region represents a major risk locus for atherosclerotic stroke. The effect of this locus on stroke appears to be independent of its relation to coronary artery disease and other stroke risk factors. Our findings support a broad role of the 9p21 region in arterial disease. Ann Neurol 2009;65:531–539
Delayed treatment with a p53 inhibitor enhances recovery in stroke brain
Authors: Luo Yu , Kuo Chi‐Chung , Shen Hui , Chou Jenny , Greig Nigel H. , Hoffer Barry J. , Wang Yun
Published: March 2009

Objective

Cerebral ischemia can activate endogenous reparative processes, such as proliferation of endogenous neural progenitor cells (NPCs) in the subventricular zone (SVZ). Most of these new cells die shortly after injury. The purpose of this study was to examine a novel strategy for treatment of stroke at 1 week after injury by enhancing the survival of ischemia‐induced endogenous NPCs in SVZ.

Methods

Adult rats were subjected to a 90‐minutes middle cerebral artery occlusion. A p53 inhibitor pifithrin‐α (PFT‐α) was administered to stroke rats from days 6 to 9 after middle cerebral artery occlusion. Locomotor behavior was measured using an activity chamber. Proliferation, survival, migration, and differentiation of endogenous NPCs were examined using quantitative reverse transcription polymerase chain reaction, terminal deoxynucleotidyl transferase‐mediated dUTP nick‐end labeling, and immunohistochemistry.

Results

PFT‐α enhanced functional recovery as assessed by a significant increase in multiple behavioral measurements. Delayed PFT‐α treatment had no effect on the cell death processes in the lesioned cortical region. However, it enhanced the survival of SVZ progenitor cells, and promoted their proliferation and migration. PFT‐α inhibited the expression of a p53‐dependent proapoptotic gene, termed PUMA (p53‐upregulated modulator of apoptosis), within the SVZ of stroke animals. The enhancement of survival/proliferation of NPCs was further found in SVZ neurospheres in tissue culture. PFT‐α dose‐dependently increased the number and size of new neurosphere formation.

Interpretation

Delayed treatment with a p53 inhibitor PFT‐α is able to modify stroke‐induced endogenous neurogenesis and improve the functional recovery in stroke animals. Ann Neurol 2009;65:520–530
Sympathetic block with botulinum toxin to treat complex regional pain syndrome
Authors: Carroll Ian , Clark J. David , Mackey Sean
Published: March 2009

Complex regional pain syndrome is a refractory pain condition with few tested therapies. We hypothesized that botulinum toxin A (BTA) would prolong analgesia after sympathetic blocks in patients with complex regional pain syndrome. We compared the duration of standard lumbar sympathetic block (LSB) with bupivacaine to LSB with bupivacaine and BTA in nine patients with refractory complex regional pain syndrome. Median time to analgesic failure was 71 (95% confidence interval, 12–253) days after LSB with BTA compared with fewer than 10 days (95% confidence interval, 0–12) after standard LSB (log‐rank, p < 0.02). BTA profoundly prolonged the analgesia from sympathetic block in this preliminary study. Ann Neurol 2009;65:348–351
Detection of human herpesvirus‐6 in cerebrospinal fluid of patients with encephalitis
Authors: Yao Karen , Honarmand Somayeh , Espinosa Alex , Akhyani Nahid , Glaser Carol , Jacobson Steven
Published: March 2009

Objective

Virus infections are the most common causes of encephalitis, a syndrome characterized by acute inflammation of the brain. More than 150 different viruses have been implicated in the pathogenesis of encephalitis; however, because of limitations with diagnostic testing, causative factors of more than half of the cases remain unknown.

Methods

To investigate whether human herpesvirus‐6 (HHV‐6) is a causative agent of encephalitis, we examined for evidence of virus infection by determining the presence of viral sequence using polymerase chain reaction and assessed HHV‐6 antibody reactivity in the cerebrospinal fluid of encephalitis patients with unknown cause. In a cohort study, we compared virus‐specific antibody levels in cerebrospinal fluid samples of patients with encephalitis, relapsing‐remitting multiple sclerosis, and other neurological diseases.

Results

Our results demonstrated increased levels of HHV‐6 IgG, as well as IgM levels, in a subset of encephalitis patients compared with other neurological diseases. Moreover, cell‐free viral DNA that is indicative of active infection was detected in 40% (14/35) of encephalitis patients, whereas no amplifiable viral sequence was found in either relapsing‐remitting MS or other neurological diseases patients. In addition, a significant correlation between polymerase chain reaction detection and anti‐HHV‐6 antibody response was also demonstrated.

Interpretation

Collectively, these results suggested HHV‐6 as a possible pathogen in a subset of encephalitis cases. Ann Neurol 2009;65:257–267
TARDBP mutations in motoneuron disease with frontotemporal lobar degeneration
Authors: Benajiba Lina , Le Ber Isabelle , Camuzat Agnès , Lacoste Mathieu , Thomas‐Anterion Catherine , Couratier Philippe , Legallic Solenn , Salachas François , Hannequin Didier , Decousus Marielle , Lacomblez Lucette , Guedj Eric , Golfier Véronique , Camu William , Dubois Bruno , Campion Dominique , Meininger Vincent , Brice Alexis ,   French Clinical and Genetic Research Network on Frontotemporal Lobar Degeneration/Frontotemporal Lobar Degeneration with Motoneuron Disease
Published: March 2009

TDP‐43 (TAR‐DNA binding protein) aggregates in neuronal inclusions in motoneuron disease (MND), as well as in frontotemporal lobar degeneration (FTLD) and FTLD associated with MND (FTLD‐MND). Mutations in TARDBP gene, coding for TDP‐43, were found in patients with pure MND. We now describe TARDBP mutations in two patients with FTLD‐MND, presenting with a behavioral variant of FTLD and semantic dementia, suggesting that TDP‐43 may also have a direct pathogenic role in FTLD disorders. Ann Neurol 2009;65:470–474
Platelet activity and outcome after intracerebral hemorrhage
Authors: Naidech Andrew M. , Bernstein Richard A. , Levasseur Kimberly , Bassin Sarice L. , Bendok Bernard R. , Batjer H. Hunt , Bleck Thomas P. , Alberts Mark J.
Published: March 2009

There are few data on platelet function in intracerebral hemorrhage (ICH). We prospectively enrolled 69 patients with ICH and measured platelet function on admission. Aspirin use before ICH was associated with reduced platelet activity. Less platelet activity was associated with intraventricular hemorrhage (516.5 [interquartile range (IQR), 454–629.25] vs 637 [IQR, 493–654] aspirin reaction units; p = 0.04) and death at 14 days (480.5 [IQR, 444.5–632.5] vs 626 [IQR, 494–652] aspirin reaction units; p = 0.04). Objective measures of platelet function on admission are associated with intraventricular hemorrhage and death after ICH. Ann Neurol 2009;65:352–356
The challenge of multiple sclerosis: How do we cure a chronic heterogeneous disease?
Authors: Weiner Howard L.
Published: March 2009

Multiple sclerosis is (MS) a T‐cell autoimmune disease characterized by a relapsing‐remitting followed by a progressive phase. Relapses are driven by the adaptive immune system and involve waves of T helper cell 1 (Th1), Th17, and CD8 cells that infiltrate the nervous system and provoke a attack. These cells are modulated by regulatory T and B cells. Infiltration of T cells into the nervous system initiates a complex immunological cascade consisting of epitope spreading, which triggers new attacks, and activation of the innate immune system (microglia, dendritic cells, astrocytes, B cells), which leads to chronic inflammation. The secondary progressive phase is due to neurodegeneration triggered by inflammation and is driven by the innate immune system. Why a shift to the progressive stage occurs and how to prevent it is a central question in MS. Effective treatment of MS must affect multiple disease pathways: suppression of proinflammatory T cells, induction of regulatory T cells, altering traffic of cells into the nervous system, protecting axons and myelin, and controlling innate immune responses. Without biomarkers, the clinical and pathological heterogeneity of MS makes treatment difficult. Treatment is further hampered by untoward adverse effects caused by immune suppression. Nonetheless, major progress has been made in the understanding and treatment of MS. There are three definitions of cure as it applies to MS: (1) halt progression of disease, (2) reverse neurological deficits, and (3) prevent MS. Although the pathways to each of these cures are linked, each requires a unique strategy. Ann Neurol 2009;65:239–248
Extensive astrocyte infection is prominent in human immunodeficiency virus–associated dementia
Authors: Churchill Melissa J. , Wesselingh Steven L. , Cowley Daniel , Pardo Carlos A. , McArthur Justin C. , Brew Bruce J. , Gorry Paul R.
Published: March 2009

Astrocyte infection with human immunodeficiency virus (HIV) is considered rare, so astrocytes are thought to play a secondary role in HIV neuropathogenesis. By combining double immunohistochemistry, laser capture microdissection, and highly sensitive multiplexed polymerase chain reaction to detect HIV DNA in single astrocytes in vivo, we showed that astrocyte infection is extensive in subjects with HIV‐associated dementia, occurring in up to 19% of GFAP+ cells. In addition, astrocyte infection frequency correlated with the severity of neuropathological changes and proximity to perivascular macrophages. Our data indicate that astrocytes can be extensively infected with HIV, and suggest an important role for HIV‐infected astrocytes in HIV neuropathogenesis. Ann Neurol 2009;66:253–258
Closed and Open Clamlike Structures Formed by Hydrogen‐Bonded Pairs of Cyclotricatechylene Anions that Contain Cationic “Meat”
Authors: Abrahams Brendan F. , FitzGerald Nicholas J. , Hudson Timothy A. , Robson Richard , Waters Tom
Published: March 2009

Eingeschnappt: Zwei Moleküle des Hexaphenols Cyclotricatechylen bilden muschelförmige Strukturen, die Kationen einschließen. Die Molekülpaare sind über variable Wasserstoffbrücken verbunden, sodass sich der Innenraum zum Einschluss von Kationen wie Rb+ oder Cs+ verkleinern und zur Einlagerung größerer Kationen wie NMe4+ und NEt4+ teilweise öffnen kann (siehe Bild).

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Composition optimization of poly(vinyl alcohol)‐/cornstarch‐blended biodegradable composite using response surface methodology
Authors: Chen Ying‐Da , Peng Jinchyau , Lui Wai‐Bun
Published: March 2009

Response surface methodology was used to analyze the effect of amylase level (X1) and glycerol level (X2) on the objective [water solubility index (WSI), water absorption index (WAI), and Max. loading] attributes of a poly(vinyl alcohol)‐/cornstarch‐blended composite. A rotable central‐composite design (CCD) was used to develop models for the objective responses. The experiments were run at die temperature 100°C with a feed rate of 25 g/min and a screw speed of 35 rpm. Responses were most affected by changes in the amylase level (X1) and to a lesser extent by glycerol level (X2). Individual contour plots of the different responses were overlaid, and regions meeting the optimum WSI of 3.03 (%), WAI of 5.08 (g gel/g dry wt), and Max. loading of 29.36 (N) were identified at the amylase level of 2.8 (mL) and the glycerol level of 92.2 (mL), respectively. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Synthesis of poly(methyl methacrylate) nanoparticles initiated by azobisisobutyronitrile using a differential microemulsion polymerization technique
Authors: Norakankorn Chaiwat , Pan Qinmin , Rempel Garry L. , Kiatkamjornwong Suda
Published: March 2009

Nanosized poly(methyl methacrylate) (PMMA) particles with a high molecular weight of 106 g mol−1 and a polydispersity index of about 1–2 were synthesized, for which 2,2′‐azobisisobutyronitrile was used as the initiator and a differential microemulsion polymerization technique was employed. The kinetics of the polymerization, the glass transition temperature, tacticity, the particle size distribution, and the morphology of the nanosized PMMA synthesized were investigated. The dependence of the number of the polymer particles (Np) and the number of the micelles (Nm) on the concentration of the surfactant was discussed. The molecular weight distribution was found to be nearly constant over the polymerization time, which was attributed to the significance of micellar polymerization. The resultant nanosized PMMA has a rich syndiotactic configuration (53–57% rr triads) with a glass transition temperature of about 125°C. A beneficial operation condition was discovered where the conversion reached a maximum at a high monomer‐to‐water ratio. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Reverse atom transfer radical graft polymerization of 4‐vinylpyridine onto inorganic oxide surfaces
Authors: Lewis Gregory T. , Nguyen Van , Shih Wen‐Yi , Cohen Yoram
Published: March 2009

Thin poly(4‐vinylpyridine) films terminally anchored onto nonporous inorganic oxide substrates were synthesized by aqueous phase reverse atom transfer radical graft polymerization (ATRGP). Surface initiators were immobilized on the inorganic substrate surface by chemically attaching glycidoxytrimethoxy silane onto the substrates followed by conversion of the glycidoxy silane into azobis silane by a reaction with 4,4′‐azobis(4‐cyanovaleric acid). Reverse ATRGP of 4‐vinylpyridine onto the active surface azo sites was carried out in a 1‐methyl‐2‐pyrrolidone/water solvent mixture using CuCl2/2,2′‐bipyridine as the catalyst‐ligand complex with initial monomer concentration [M]0 = 2.32M at 90°C. Controlled radical polymerization was achieved at catalyst to initiator molar ratios of 2 : 1 and 3 : 1, with a catalyst to ligand molar ratio of 1 : 2. Controlled polymerization was indicated by a first‐order rate of polymerization kinetics, with respect to monomer conversion at the surface and in solution, the linear increase of the P4VP graft yield with time, and a low polydispersity index (PDI < 1.40). The highest graft yield of 8 mg/m2 was achieved at a 3 : 1 catalyst to initiator molar ratio which corresponded to a number‐average molecular weight of 11,500 g/mol, surface density of 0.69 μmol/m2, and a polydispersity index of 1.28. AFM surface analysis of the grafted polymer films, prepared by reverse ATRGP of 4VP, revealed a decrease in the RMS surface roughness (RRMS = 1.04 nm) and feature size (feature diameter = 20–45 nm), relative to uncontrolled free radical graft polymerization (RRMS = 1.42 nm; feature diameter = 60–145 nm), thereby providing an additional indication that a denser and controlled reaction was achieved via reverse ATRGP. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
High‐quality cellulose triacetate prepared from bamboo dissolving pulp
Authors: He Jianxin , Zhang Ming , Cui Shizhong , Wang Shan‐Yuan
Published: March 2009

Cellulose triacetate (CTA) was prepared from high‐grade bamboo dissolving pulp in general acetylation medium of acetic acid/acetic anhydride/sulfuric acid system. Despite its properties being improved compared with these of CTA prepared from viscose bamboo pulp, many insoluble residues still remained in its acetylation medium, which resulted in the decrease of the brightness and thermal stability of prepared CTA. Characterization of the insoluble residue indicated that its formation was associated with a higher content of xylan and ash in high‐grade bamboo pulp than in high‐grade hardwood pulp, in which insoluble residue was negligible. Because of the poor solubility of xylan diacetate (XDA) in acetylation medium, the insoluble residue formed through the aggregation of XDA and CTA by ultrastructural effects of the pulps during the precipitation of XDA. An addition to the good solvent of XDA, such as 1,2‐dichloroethane to acetylation medium of high‐grade bamboo pulp, could release the aggregation of XDA and CTA and dissolve the insoluble residue, which could lead to the improvement of the transmittance of reaction solution, as well as the properties of CTA prepared such as brightness and thermal stability. This study showed that high‐quality CTA could be prepared from high‐grade bamboo dissolving pulp in acetylation with an addition of solvent. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Elucidation of the nanoparticle effect on the grafting of vinyl monomers onto cotton fabric
Authors: Effenberger F. , Schweizer M. , Mohamed W. S.
Published: March 2009

The grafting emulsion polymerization of vinyl monomers onto cotton was carried out in the presence of double‐modified montmorillonite clay. The obtained results show that grafting with glycidyl methacrylate/montmorillonite gave a higher rate of grafting than grafting with methyl methacrylate/montmorillonite in all clay percentages, and also, the grafting yield of glycidyl methacrylate monomer onto cotton in the presence of montmorillonite clay had a higher value than that in the absence of the clay for all factors studied. Cotton grafted with glycidyl methacrylate/montmorillonite with a graft yield of about 50% was prepared according to the emulsion polymerization technique and was treated with different concentrations of dibutylamine solutions ranging from 1 to 4%. The obtained samples were characterized according to nitrogen content, thermal stability, scanning electron microscopy, mechanical properties, water absorption, and color strength according to acid, basic, and reactive dyes. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
Experimental failure analysis of two‐serial‐bolted composite plates
Authors: Sen Faruk , Sayman Onur
Published: March 2009

In this study, a failure analysis of two‐serial‐bolted glass‐fiber‐reinforced epoxy composite plates was performed. To determine the influences of the joint geometry and stacking sequences on the bearing strength and failure mode, parametric studies were carried out experimentally. Three different geometrical parameters—the ratio of the edge distance to the hole diameter (E/D), the ratio of the plate width to the hole diameter (W/D), and the ratio of the distance between two holes to the hole diameter (K/D)—were considered. For this reason, the E/D, W/D, and K/D ratios were designed to range from 1 to 5, from 2 to 5, and from 3 to 5, respectively. Furthermore, the tests were performed with various preload moments (2, 3, 4, and 5 Nm) and without any preload moments (0 Nm). Because of the observed effect of the material parameters on the failure behavior, composite laminated plates were stacked in two different stacking sequences: [0°/0°/30°/30°]s and [0°/0°/45°/45°]s. The experimental results indicated that the failure response of the two‐serial‐bolted joints were strictly affected by the material parameters, geometrical parameters, and values of the applied preload moments. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009
The structure of the hyperlink network formed by the Web pages of Japanese public libraries
Authors: Kawamura Shuntaro , Otake Yo‐Hey , Suzuki Takafumi
Published: March 2009

This article analyzes the structure of the hyperlink network formed by the Web pages of Japanese public libraries and its relationship with the network formed by Inter‐Library Loans (ILLs), the traditional system of cooperation among public libraries. Our results indicate that (a) the hyperlink network is effectively connected in the sense that each library is reachable from other libraries by clicking a few links and (b) the network has many groups of libraries that cooperate with each other. Most of the cliques consist of prefectural libraries or libraries in the same prefecture. The hyperlink network shows two of the same tendencies as the ILL network: (a) The connection among libraries that are geographically close to each other or in the same administrative unit is strong, and (b) prefectural libraries occupy the central position. There are differences between them, however, in terms of the amount of ILLs and cliques. We conclude that Japanese public libraries have formed a network on the Web that is strongly affected by traditional cooperation, but also incorporates some new types of cooperation from the perspective of cliques.
Twenty‐year outcome for individuals with autism and average or near‐average cognitive abilities
Authors: Farley Megan A. , McMahon William M. , Fombonne Eric , Jenson William R. , Miller Judith , Gardner Michael , Block Heidi , Pingree Carmen B. , Ritvo Edward R. , Ritvo Riva Arielle , Coon Hilary
Published: March 2009

Previous studies found substantial variability in adult outcome for people with autism whose cognitive functioning was within the near‐average and average ranges. This study examined adult outcome for 41 such individuals (38 men and 3 women) originally identified through an epidemiological survey of autism in Utah. Mean age at the time of their previous cognitive assessment was 7.2 years (SD=4.1, range=3.1–25.9 years) and at follow‐up was 32.5 years (SD=5.7 years, range=22.3–46.4 years). Outcome measures included standardized assessments of diagnostic status, cognitive ability, and adaptive behavior. Additional information collected concerned demographic variables, indicators of independence, social relationships, medical and psychiatric conditions, and social service use. Outcomes for this sample were better than outcomes described in previous work on individuals with similar cognitive functioning. For example, half of the participants were rated as “Very Good” or “Good” on a global outcome measure. As in previous studies, there was considerable variability in measured cognitive ability over time. Over half of the sample had large gains or losses of cognitive ability of greater than 1 standard deviation. Cognitive gain was associated with better outcome, as was better adaptive functioning. While all participants had baseline IQs in the nonimpaired range, there was limited evidence to support the use of other early childhood variables to predict adult outcome.
Effects of cellulase and xylanase enzymes on the deconstruction of solids from pretreatment of poplar by leading technologies
Authors: Kumar Rajeev , Wyman Charles E.
Published: March 2009

Comparative data is presented on glucose and xylose release for enzymatic hydrolysis of solids produced by pretreatment of poplar wood by ammonia fiber expansion (AFEX), ammonia recycled percolation (ARP), controlled pH, dilute acid, flowthrough (FT), lime, and sulfur dioxide (SO2) technologies. Sugar solubilization was measured for times of up to 72 h using cellulase supplemented with β‐glucosidase at an activity ratio of 1:2, respectively, at combined protein mass loadings of 5.8–116 mg/g of glucan in poplar wood prior to pretreatment. In addition, the enzyme cocktail was augmented with up to 11.0 g of xylanase protein per gram of cellulase protein at combined cellulase and β‐glucosidase mass loadings of 14.5 and 29.0 mg protein (about 7.5 and 15 FPU, respectively)/g of original potential glucose to evaluate cellulase–xylanase interactions. All pretreated poplar solids required high protein loadings to realize good sugar yields via enzymatic hydrolysis, and performance tended to be better for low pH pretreatments by dilute sulfuric acid and sulfur dioxide, possibly due to higher xylose removal. Glucose release increased nearly linearly with residual xylose removal by enzymes for all pretreatments, xylanase leverage on glucan removal decreased at high cellulase loadings. Washing the solids improved digestion for all pretreatments and was particularly beneficial for controlled pH pretreatment. Furthermore, incubation of pretreated solids with BSA, Tween 20, or PEG6000 prior to adding enzymes enhanced yields, but the effectiveness of these additives varied with the type of pretreatment. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009