bluuebunny/crossref_metadata_2025 huggingface dataset:
Increased production of soluble CD23 in rheumatoid arthritis, and its regulation by interleukin‐4
Authors: Chomarat Pascale , Briolay Jérôme , Banchereau Jacques , Miossec Pierre
Published: May 2012

Objective. To assess CD23 status in rheumatoid arthritis (RA) patients, as defined by the levels of CD23 expression on peripheral blood mononuclear cells (PBMC), the levels of soluble CD23 (sCD23) in sera, and the production of sCD23 by PBMC cultures and its regulation by interleukin‐4 (IL‐4).

Methods. CD23 expression as determined by double fluorescence‐activated cell sorter analysis and sCD23 production as determined by immunoradiometric assay were investigated in 24 RA patients and 21 controls. Soluble CD23 was measured in sera and supernatants of PBMC, activated with polyclonal activators (pokeweed mitogen [PWM] or Staphylococcus aureus Cowan strain 1, [SAC]) used either alone or in combination with IL‐2 or IL‐4.

Results. The percentage of B cells expressing CD23 and serum levels of sCD23 were increased in patients with RA. IL‐4 was a potent inducer of sCD23 production in supernatants, whereas IL‐2 was inactive. Costimulation with SAC or PWM did not increase the effect obtained with IL‐4 alone. When sCD23 levels in RA and control supernatants were compared, spontaneous production was found to be increased in RA PBMC. This difference from control values was even more pronounced when sCD23 levels in PBMC and purified B cells in response to IL‐4, either alone or in combination with SAC or PWM, were tested. In the same supernatants, the increased secretion of sCD23 induced by IL‐4 was associated with an inhibitory effect of IL‐4 on Ig production, a phenomenon that was more pronounced in RA PBMC than in controls.

Conclusion. CD23 status in RA is characterized by increased expression of CD23 on B cells, increased production of sCD23 in sera and supernatants, and increased sensitivity of RA PBMC and B cells to IL‐4.
Cost‐effectiveness of increased telephone contact for patients with osteoarthritis: A randomized, controlled trial
Authors: Weinberger Morris , Tierney William M. , Cowper Patricia A. , Katz Barry P. , Booher Patricia A.
Published: May 2012

Objective. To evaluate the cost‐effectiveness of telephone intervention for patients with osteoarthritis.

Methods. Randomized, controlled trial.

Results. The intervention did not significantly increase health care costs. The annual costs for a 1‐unit improvement in physical functioning and in pain, as measured by the Arthritis Impact Measurement Scales, were $70.86 and $31.00, respectively.

Conclusion. Telephone contact is a potentially cost‐effective intervention in osteoarthritis.
Effects of hyaluronic acid on the release of proteoglycan from the cell matrix in rabbit chondrocyte cultures in the presence and absence of cytokines
Authors: Shimazu Atsushi , Jikko Akitoshi , Iwamoto Masahiro , Koike Tatsuya , Yan Weiqun , Okada Yasunori , Shinmei Masayuki , Nakamura Shigeo , Kato Yukio
Published: May 2012

Objective.To investigate the effects of hyaluronic acid (HA) on the release of proteoglycan by cultured rabbit chondrocytes.

Methods.Articular cartilage chondrocytes were isolated from the knee joints of New Zealand white rabbits. Proteoglycan synthesis after incubation with HA was determined by measuring35S‐sulfate incorporation. Cells incubated with HA were labeled with3H‐glucosamine and applied to a Sepharose CL‐2B column. After incubation of confluent cells with35S‐sulfate and then with HA in various concentrations in the presence or absence of cytokines, proteoglycan release from the cell matrix layer was measured.

Results.HA (Mr3 × 105to 19 × 105), at 10 μg/ml to 1 mg/ml, had little effect on the incorporation of35S‐sulfate or3H‐glucosamine into cartilage matrix proteoglycans, or on the hydrodynamic size of proteoglycan monomers, in rabbit chondrocyte cultures. However, at 10–1,000 μg/ml, HA suppressed the release of35S‐proteoglycans from the cell matrix layer into the medium in the presence and absence of interleukin‐1, tumor necrosis factor α, or basic fibroblast growth factor.

Conclusion.These results suggest that HA is a potent inhibitor of the displacement of matrix proteoglycan into culture medium.
Prevention of autoimmune inflammatory polyarthritis in male new zealand black/kn mice by transplantation of bone marrow cells plus bone (stromal cells)
Authors: Nakagawa Takuma , Nagata Norikazu , Hosaka Naoki , Ogawa Ryoukei , Nakamura Kunie , Ikehara Susumu
Published: May 2012

Objective. To prevent polyarthritis in male New Zealand black/KN (NZB/KN) mice by transplantation of both bone marrow cells (BMC) and bone (to recruit stromal cells) from normal mice.

Methods. Arthritic lesions in male NZB/KN mice injected intravenously with BMC plus bone from C57BI/10 mice were compared with those in untreated male NZB/KN mice.

Results. Male NZB/KN mice engrafted with BMC plus bone were both radiologically and histopathologically normal, and had decreased production of anti‐single‐stranded DNA antibodies and rheumatoid factors at 8–12 months of age.

Conclusion. Bone marrow transplantation prevented polyarthritis in male NZB/KN mice.
A unique presentation of multicentric reticulohistiocytosis in pregnancy
Authors: Conaghan Philip , Miller Marian , Dowling John P. , Cowen Peter , Littlejohn Geoffrey
Published: May 2012

We describe a patient with multicentric reticulo‐histiocytosis who presented, during the second trimester of pregnancy, with symmetric polyarthritis, marked erythematous, pulsatile synovial swelling of the distal interphalangeal joints of both hands, and widespread telangiectasias. She did not have the typical skin manifestations of multicentric reticulohistiocytosis. The erythema and pulsatility of the synovial swellings of the distal interphalangeal joints resolved after delivery, but she continued to have widespread active synovitis, which did not resolve until treatment with low‐dose oral methotrexate was instituted.
Derivation and validation of the Systemic Lupus International Collaborating Clinics classification criteria for systemic lupus erythematosus
Authors: Petri Michelle , Orbai Ana‐Maria , Alarcón Graciela S. , Gordon Caroline , Merrill Joan T. , Fortin Paul R. , Bruce Ian N. , Isenberg David , Wallace Daniel J. , Nived Ola , Sturfelt Gunnar , Ramsey‐Goldman Rosalind , Bae Sang‐Cheol , Hanly John G. , Sánchez‐Guerrero Jorge , Clarke Ann , Aranow Cynthia , Manzi Susan , Urowitz Murray , Gladman Dafna , Kalunian Kenneth , Costner Melissa , Werth Victoria P. , Zoma Asad , Bernatsky Sasha , Ruiz‐Irastorza Guillermo , Khamashta Munther A. , Jacobsen Soren , Buyon Jill P. , Maddison Peter , Dooley Mary Anne , van Vollenhoven Ronald F. , Ginzler Ellen , Stoll Thomas , Peschken Christine , Jorizzo Joseph L. , Callen Jeffrey P. , Lim S. Sam , Fessler Barri J. , Inanc Murat , Kamen Diane L. , Rahman Anisur , Steinsson Kristjan , Franks Andrew G. , Sigler Lisa , Hameed Suhail , Fang Hong , Pham Ngoc , Brey Robin , Weisman Michael H. , McGwin Gerald , Magder Laurence S.
Published: May 2012

Objective

The Systemic Lupus International Collaborating Clinics (SLICC) group revised and validated the American College of Rheumatology (ACR) systemic lupus erythematosus (SLE) classification criteria in order to improve clinical relevance, meet stringent methodology requirements, and incorporate new knowledge regarding the immunology of SLE.

Methods

The classification criteria were derived from a set of 702 expert‐rated patient scenarios. Recursive partitioning was used to derive an initial rule that was simplified and refined based on SLICC physician consensus. The SLICC group validated the classification criteria in a new validation sample of 690 new expert‐rated patient scenarios.

Results

Seventeen criteria were identified. In the derivation set, the SLICC classification criteria resulted in fewer misclassifications compared with the current ACR classification criteria (49 versus 70; P = 0.0082) and had greater sensitivity (94% versus 86%; P < 0.0001) and equal specificity (92% versus 93%; P = 0.39). In the validation set, the SLICC classification criteria resulted in fewer misclassifications compared with the current ACR classification criteria (62 versus 74; P = 0.24) and had greater sensitivity (97% versus 83%; P < 0.0001) but lower specificity (84% versus 96%; P < 0.0001).

Conclusion

The new SLICC classification criteria performed well in a large set of patient scenarios rated by experts. According to the SLICC rule for the classification of SLE, the patient must satisfy at least 4 criteria, including at least one clinical criterion and one immunologic criterion OR the patient must have biopsy‐proven lupus nephritis in the presence of antinuclear antibodies or anti–double‐stranded DNA antibodies.
N‐acetylcysteine reduces disease activity by blocking mammalian target of rapamycin in T cells from systemic lupus erythematosus patients: A randomized, double‐blind, placebo‐controlled trial
Authors: Lai Zhi‐Wei , Hanczko Robert , Bonilla Eduardo , Caza Tiffany N. , Clair Brandon , Bartos Adam , Miklossy Gabriella , Jimah John , Doherty Edward , Tily Hajra , Francis Lisa , Garcia Ricardo , Dawood Maha , Yu Jianghong , Ramos Irene , Coman Ioana , Faraone Stephen V. , Phillips Paul E. , Perl Andras
Published: May 2012

Objective

Systemic lupus erythematosus (SLE) patients exhibit T cell dysfunction, which can be regulated through mitochondrial transmembrane potential (Δψm) and mammalian target of rapamycin (mTOR) by glutathione (GSH). This randomized, double‐blind, placebo‐controlled study was undertaken to examine the safety, tolerance, and efficacy of the GSH precursor N‐acetylcysteine (NAC).

Methods

A total of 36 SLE patients received either daily placebo or 1.2 gm, 2.4 gm, or 4.8 gm of NAC. Disease activity was evaluated monthly by the British Isles Lupus Assessment Group (BILAG) index, the SLE Disease Activity Index (SLEDAI), and the Fatigue Assessment Scale (FAS) before, during, and after a 3‐month treatment period. Mitochondrial transmembrane potential and mTOR were assessed by flow cytometry. Forty‐two healthy subjects matched to patients for age, sex, and ethnicity were studied as controls.

Results

NAC up to 2.4 gm/day was tolerated by all patients, while 33% of those receiving 4.8 gm/day had reversible nausea. Placebo or NAC 1.2 gm/day did not influence disease activity. Considered together, 2.4 gm and 4.8 gm NAC reduced the SLEDAI score after 1 month (P = 0.0007), 2 months (P = 0.0009), 3 months (P = 0.0030), and 4 months (P = 0.0046); the BILAG score after 1 month (P = 0.029) and 3 months (P = 0.009); and the FAS score after 2 months (P = 0.0006) and 3 months (P = 0.005). NAC increased Δψm (P = 0.0001) in all T cells, profoundly reduced mTOR activity (P = 0.0009), enhanced apoptosis (P = 0.0004), reversed expansion of CD4−CD8− T cells (mean ± SEM 1.35 ± 0.12‐fold change; P = 0.008), stimulated FoxP3 expression in CD4+CD25+ T cells (P = 0.045), and reduced anti‐DNA production (P = 0.049).

Conclusion

This pilot study suggests that NAC safely improves lupus disease activity by blocking mTOR in T lymphocytes.
Protein kinase Cδ oxidation contributes to ERK inactivation in lupus T cells
Authors: Gorelik Gabriela J. , Yarlagadda Sushma , Richardson Bruce C.
Published: May 2012

Objective

CD4+ T cells from patients with active lupus have impaired ERK pathway signaling that decreases DNA methyltransferase expression, resulting in DNA demethylation, overexpression of immune genes, and autoimmunity. The ERK pathway defect is due to impaired phosphorylation of T505 in the protein kinase Cδ (PKCδ) activation loop. However, the mechanisms that prevent PKCδ T505 phosphorylation in lupus T cells are unknown. Others have reported that oxidative modifications, and nitration in particular, of T cells as well as serum proteins correlate with lupus disease activity. We undertook this study to test our hypothesis that nitration inactivates PKCδ, contributing to impaired ERK pathway signaling in lupus T cells.

Methods

CD4+ T cells were purified from lupus patients and controls and then stimulated with phorbol myristate acetate (PMA). Signaling protein levels, nitration, and phosphorylation were quantitated by immunoprecipitation and immunoblotting of T cell lysates. Transfections were performed by electroporation.

Results

Treating CD4+ T cells with peroxynitrite nitrated PKCδ, preventing PKCδ T505 phosphorylation and inhibiting ERK pathway signaling similar to that observed in lupus T cells. Patients with active lupus had higher nitrated T cell PKCδ levels than did controls, which correlated directly with disease activity, and antinitrotyrosine immunoprecipitations demonstrated that nitrated PKCδ, but not unmodified PKCδ, was refractory to PMA‐stimulated T505 phosphorylation, similar to PKCδ in peroxynitrite‐treated cells.

Conclusion

Oxidative stress causes PKCδ nitration, which prevents its phosphorylation and contributes to the decreased ERK signaling in lupus T cells. These results identify PKCδ as a link between oxidative stress and the T cell epigenetic modifications in lupus.
Type I interferons modulate vascular function, repair, thrombosis, and plaque progression in murine models of lupus and atherosclerosis
Authors: Thacker Seth G. , Zhao Wenpu , Smith Carolyne K. , Luo Wei , Wang Hui , Vivekanandan‐Giri Anuradha , Rabquer Bradley J. , Koch Alisa E. , Pennathur Subramaniam , Davidson Anne , Eitzman Daniel T. , Kaplan Mariana J.
Published: May 2012

Objective

Patients with systemic lupus erythematosus (SLE) have a notable increase in atherothrombotic cardiovascular disease (CVD) which is not explained by the Framingham risk equation. In vitro studies indicate that type I interferons (IFNs) may play prominent roles in increased CV risk in SLE. However, the in vivo relevance of these findings, with regard to the development of CVD, has not been characterized. This study was undertaken to examine the role of type I IFNs in endothelial dysfunction, aberrant vascular repair, and atherothrombosis in murine models of lupus and atherosclerosis.

Methods

Lupus‐prone New Zealand mixed 2328 (NZM) mice and atherosclerosis‐prone apolipoprotein E– knockout (apoE−/−) mice were compared to mice lacking type I IFN receptor (INZM and apoE−/−IFNAR−/− mice, respectively) with regard to endothelial vasodilatory function, endothelial progenitor cell (EPC) function, in vivo neoangiogenesis, plaque development, and occlusive thrombosis. Similar experiments were performed using NZM and apoE−/− mice exposed to an IFNα‐containing or empty adenovirus.

Results

Loss of type I IFN receptor signaling improved endothelium‐dependent vasorelaxation, lipoprotein parameters, EPC numbers and function, and neoangiogenesis in lupus‐prone mice, independent of disease activity or sex. Further, acute exposure to IFNα impaired endothelial vasorelaxation and EPC function in lupus‐prone and non–lupus‐prone mice. Decreased atherosclerosis severity and arterial inflammatory infiltrates and increased neoangiogenesis were observed in apoE−/−IFNAR−/− mice, compared to apoE−/− mice, while NZM and apoE−/− mice exposed to IFNα developed accelerated thrombosis and platelet activation.

Conclusion

These results support the hypothesis that type I IFNs play key roles in the development of premature CVD in SLE and, potentially, in the general population, through pleiotropic deleterious effects on the vasculature.
Decreased microRNA‐142‐3p/5p expression causes CD4+ T cell activation and B cell hyperstimulation in systemic lupus erythematosus
Authors: Ding Shu , Liang Yunsheng , Zhao Ming , Liang Gongping , Long Hai , Zhao Sha , Wang Yu , Yin Heng , Zhang Peng , Zhang Qing , Lu Qianjin
Published: May 2012

Objective

To examine the role of microRNA‐142‐3p/5p (miR‐142‐3p/5p) in the development of autoimmunity in patients with systemic lupus erythematosus (SLE).

Methods

MicroRNA‐142‐3p/5p expression levels were determined by real‐time quantitative polymerase chain reaction, and potential target genes were verified using luciferase reporter gene assays. The effects of miR‐142‐3p/5p on T cell function were assessed by transfection with miR‐142‐3p/5p inhibitors or mimics. Histone modifications and methylation levels within a putative regulatory region of the miR‐142 locus were detected by chromatin immunoprecipitation assay and bisulfite sequencing, respectively.

Results

We confirmed that miR‐142‐3p and miR‐142‐5p were significantly down‐regulated in SLE CD4+ T cells compared with healthy controls and observed that miR‐142‐3p/5p levels were inversely correlated with the putative SLE‐related targets signaling lymphocytic activation molecule–associated protein (SAP), CD84, and interleukin‐10 (IL‐10). We demonstrated that miR‐142‐3p and miR‐142‐5p directly inhibit SAP, CD84, and IL‐10 translation, and that reduced miR‐142‐3p/5p expression in CD4+ T cells can significantly increase protein levels of these target genes. Furthermore, inhibiting miR‐142‐3p/5p in healthy donor CD4+ T cells caused T cell overactivation and B cell hyperstimulation, whereas overexpression of miR‐142‐3p/5p in SLE CD4+ T cells had the opposite effect. We also observed that the decrease in miR‐142 expression in SLE CD4+ T cells correlated with changes to histone modifications and DNA methylation levels upstream of the miR‐142 precursor sequence.

Conclusion

The results of this study indicate that reduced expression of miR‐142‐3p/5p in the CD4+ T cells of patients with SLE causes T cell activity and B cell hyperstimulation.
Mitochondrial dysfunction increases inflammatory responsiveness to cytokines in normal human chondrocytes
Authors: Vaamonde‐García Carlos , Riveiro‐Naveira Romina R. , Valcárcel‐Ares Marta N. , Hermida‐Carballo Laura , Blanco Francisco J. , López‐Armada María J.
Published: May 2012

Objective

Alterations in mitochondria play a key role in the pathogenesis of osteoarthritis (OA). The role of inflammation in the progression of OA has also acquired important new dimensions. This study was undertaken to evaluate the potential role of mitochondrial dysfunction in increasing the inflammatory response of normal human chondrocytes to cytokines.

Methods

Mitochondrial dysfunction was induced by commonly used inhibitors. Interleukin‐1β (IL‐1β) and tumor necrosis factor α (TNFα) were used as inflammatory mediators. IL‐8 and cyclooxygenase 2 (COX‐2) protein and messenger RNA (mRNA) expression and prostaglandin E2 (PGE2) levels were assessed. The chemotactic activity of neutrophils was assayed. Additionally, inhibitors of reactive oxygen species (ROS) and NF‐κB were used to identify possible inflammatory response pathways induced by mitochondrial dysfunction, and the effects of the natural antioxidant resveratrol were tested.

Results

Pretreatment with antimycin A or oligomycin (inhibitors of mitochondrial respiratory chain complexes III and V, respectively) triggered a strong potentiation of IL‐1β–induced IL‐8 mRNA and protein expression (mean ± SEM at 18 hours 5,932 ± 1,995 pg/50,000 cells for IL‐1β alone versus 16,241 ± 5,843 pg/50,000 cells for antimycin A plus IL‐1β and 20,087 ± 5,407 pg/50,000 cells for oligomycin plus IL‐1β; P < 0.05). Similar results were observed with TNFα or when expression of the inflammatory mediator COX‐2 or PGE2 production was assessed. Mitochondrial dysfunction increased the chemotactic activity induced by cytokines, and ROS and NF‐κB inhibitors decreased the production of IL‐8. Resveratrol significantly reduced the inflammatory response.

Conclusion

Our findings indicate that mitochondrial dysfunction could amplify the responsiveness to cytokine‐induced chondrocyte inflammation through ROS production and NF‐κB activation. This pathway might lead to the impairment of cartilage and joint function in OA.
Anatomical Sciences Education Vol. 5, Issue 3, 2012 Cover Image
Authors: Ullah Shahnoor M. , Bodrogi Andrew , Cristea Octav , Johnson Marjorie , McAlister Vivian C.
Published: May 2012

Medical students at the Schulich School of Medicine and Dentistry at The University of Western Ontario in London, Ontario, Canada, learn clinical facts about the hepatobiliary system as transplant surgeon Dr. Vivian McAlister (at the far right) demonstrates Whipple's procedure in the anatomy laboratory. In this issue of ASE, Ullah and colleagues describe an extracurricular student initiative known as the Surgically Oriented Anatomy Program (SOAP), which aims to deliver anatomy teaching from a surgical perspective through the philosophy of “education through recreation”.
Konstruktionsregeln für Parkbauten in Betonbauweise
Authors: Schöppel Klaus , Stenzel Gerhard
Published: May 2012

In diesem Beitrag werden Konstruktionsregeln für Parkbauten dargestellt. Dabei werden Regel‐ und Sonderbauweisen definiert. Eine Planung gemäß den vorgeschlagenen Regelbauweisen ergibt regelkonforme Parkbauten, die der üblichen Gebrauchstauglichkeit und Dauerhaftigkeit derartiger Bauwerke entsprechen. Konstruktionsmöglichkeiten von Parkbauten, die von den anerkannten Regeln der Technik teilweise abweichen, werden als Sonderbauweisen bezeichnet und hinsichtlich der Risiken infolge der Abweichungen erörtert.

Falls der Bauherr eine Sonderbauweise wünscht, ist der Bauherr vom Planer auf den höheren Wartungs‐ und Instandsetzungsbedarf und die geringere Dauerhaftigkeit und Werthaltigkeit der Immobilie eindeutig hinzuweisen.

Construction Standards for Car Parks in Concrete Design

In this paper construction standards for car parks are described. Thereby a difference is made between standard constructions and special constructions. A design following the standard constructions leads to state‐of‐the‐art car parks, which show an appropriate serviceability and durability. Construction methods of car parks, which do not fully follow the generally accepted codes of practice are denoted special constructions and their risks caused by the discrepancies from the generally accepted codes of practice are discussed.

If the building owner wants to have a special construction executed, the designer should clearly advise the owner of the exceeded maintenance and repair demand and the reduced durability and real property value.
Sicherheitsanalyse und statisch konstruktive Ertüchtigung des Naturzugkühlturms Block E im Kraftwerk Niederaußem der RWE‐Power AG
Authors: Altmeyer Felix , Weigl Joachim , Scharf Henning
Published: May 2012

Bauwerke sind ab dem Zeitpunkt ihrer Erstellung durch betriebliche Beanspruchung sowie Bewetterung einem Alterungsprozess unterworfen. Sie altern während der Standzeit. Tragwerke, die zum Zeitpunkt der Erstellung in Übereinstimmung mit den gültigen Normen standen, sind nach neuer Normenlage auf einmal “schwach” dimensioniert. Neue, genauere Berechnungsmethoden und bessere Kenntnis der Beanspruchung zeigen allerdings auch, dass nicht alle nach alter Normengeneration bemessenen Tragwerke den tatsächlichen Einwirkungen in vollem Umfang gerecht werden. Hier sind vor allem die mit der DIN 1045‐1 erweiterten Anforderungen an die Gebrauchstauglichkeit zu nennen.

Der vorliegende Beitrag behandelt einen Naturzugkühlturm aus dem Jahr 1968 im Kraftwerk Niederaußem, der durch den Betrieb von nachträglich installierten Abgaseinleitungen Schädigungen erfahren hat. Geschildert werden die Bestandsaufnahme des Kühlturms, die Beurteilung der Standsicherheit mit nichtlinearen Methoden und die sich hieraus ableitende notwendige Sanierung der Kühlturmschale, um den sicheren Betrieb für die weitere Laufzeit zu gewährleisten.

Safety analysis and rehabilitation of the natural draft cooling tower Block E at the power plant of Niederaußem

From the moment of their erection, buildings are exposed to weather and loading. They constantly deteriorate.
Buildings that have been erected in compliance with the relevant codes are all of a sudden “weak” compared to current codes and regulations.

New and more “close to reality” methods of calculation and better knowledge of the loading situation shows that not all buildings that are built within the regulations of the old codes have the ability to fulfil the actual demands. This applies in particular to the serviceability limit state of the DIN 1045‐1.

The report at hand deals with a natural draft cooling tower from 1968 at the power plant of Niederaußem, which has been damaged as a cause of the operation of a subsequently built flue gas discharge unit.

It deals with the surveying of the cooling tower, the estimation of the ultimate limit state with nonlinear methods of calculation and the necessary rehabilitation to guarantee a safe operation during the remaining life time.
Entwicklung eines brandbeständigen ultrahochfesten Betons für hochdynamische Beanspruchungen
Authors: Scheydt Jennifer C. , Millon Oliver , Müller Harald S. , Thoma Klaus
Published: May 2012

Seit einigen Jahren setzt sich die Bundesregierung verstärkt mit den Auswirkungen extremer Ereignisse wie Naturkatastrophen, technische Großunfälle und insbesondere auch Terroranschläge auseinander. Infolgedessen wurde im Jahr 2007 das Programm “Forschung für die zivile Sicherheit” durch das Bundesministerium für Bildung und Forschung (BMBF) ins Leben gerufen. Hierin sollten Lösungen für den Umgang mit derartigen Bedrohungsszenarien gesucht werden.

Ein besonderes Gefährdungspotenzial besteht hierbei für Infrastrukturen des öffentlichen Verkehrs wie Tunnel oder Brücken, deren Ausfall schwere Folgen für die Versorgung der Bevölkerung haben kann. Um für den Fall der Extrembeanspruchung derartiger Infrastrukturbauwerke den größtmöglichen Schutz zu gewährleisten, muss die Tragfähigkeit der baulichen Strukturen verbessert werden. Das Forschungsvorhaben AISIS hat sich im Rahmen dessen mit der Entwicklung eines brandbeständigen ultrahochfesten Betons für hochdynamische Beanspruchungen befasst. Die erzielten Forschungsergebnisse sind nachfolgend dargelegt.

Development of an ultra high strength concrete with increased resistance to fire and explosive loading

In recent years, the German Government exceedingly deals with the consequences of extreme events such as natural disasters, technical accidents and terrorist attacks. In 2007, the program “Research for Civil Security” was set up by the German Federal Ministry of Education and Research (BMBF) which aimed at solutions for the handling of such menaces.

Particularly the breakdown of public transport buildings (e. g. tunnels, bridges) is supposed to involve a drastic undersupply of general public in case of attack. To avoid that, the load bearing capacity of these buildings has to be enhanced. In this context, an ultra high strength concrete with increased resistance to fire and explosive loading was developed within the research project AISIS. The project results are presented within this article.
vKASS: a surgical procedure simulation system for arthroscopic anterior cruciate ligament reconstruction
Authors: Wang Yanzhen , Xiong Yueshan , Xu Kai , Liu Dong
Published: May 2012

Arthroscopic surgeries, which are widely used for anterior cruciate ligament (ACL) reconstruction, not only require advanced hand–eye coordination but also involve complicated surgical procedure, necessitating simulation‐based training for surgeons. This paper describes a surgical procedure simulation system for the training of arthroscopic ACL reconstruction. Different from existing simulation‐based training systems for basic surgical skills, this system provides a complete simulation for the entire procedure of arthroscopic ACL reconstruction, involving operations such as puncturing, probing, incision, and drilling. In this system, we employ a linear elastic finite element method and position‐based dynamics for deformable modeling. Simplified vertex duplicating method and an implementation of real‐time Boolean operations are proposed for the topological change of tissue models involved in the incision simulation and tunnel construction. Two specially designed force feedback models are introduced for the haptic rendering of probing and drilling operations. By using these fast and stable simulation methods, this system is able to provide real‐time realistic graphical and haptic feedback to the user, making it efficient and practical for training purpose. Feedback from the surgeon trainees shows that this system is very effective in training not only for basic surgical skills but also for the complex surgical procedure. Copyright © 2012 John Wiley & Sons, Ltd.
Suture‐mediated arterial access site closure after transfemoral aortic valve implantation
Authors: Kahlert Philipp , Al‐Rashid Fadi , Plicht Björn , Konorza Thomas , Neumann Till , Thielmann Matthias , Wendt Daniel , Erbel Raimund , Eggebrecht Holger
Published: May 2012

Objectives

To evaluate feasibility, safety and efficacy of percutaneous arterial access site closure after transfemoral, transcatheter aortic valve implantation (TF‐TAVI) using a single, commercially available six French monofilament suture‐mediated vascular closure device (VCD) in “preclosure” technique.

Background

Currently, TF‐TAVI is evolving into a completely percutaneous procedure. However, percutaneous access site closure still remains a major technical challenge with room for improvement.

Methods

94 of 144 consecutive patients underwent completely percutaneous TF‐TAVI using following technique for access site closure: After puncture of the common femoral artery using fluoroscopy and contralateral angiography for guidance, the VCD was deployed prior further predilatation of the vessel and insertion of the large‐bore introducer sheath. At the end of the procedure, the preloaded sutures were tied for final hemostasis and crossover angiography was used for postprocedural evaluation of the access vessel.

Results

Application of the VCD was technically successful in all cases, resulting in an efficient hemostasis with cessation of any bleeding within 10 min of final knot‐tying in 83 of the 94 patients, and there was only one closure‐failure with continuous bleeding despite prolonged manual compression requiring endovascular treatment. In addition, we observed four closure‐related access vessel stenoses of hemodynamic relevance requiring endovascular treatment in three and surgical repair in one patient. However, interventional and surgical repair was not associated with death or irreversible end‐organ damage and all patients recovered without sequelae.

Conclusion

“Preclosure” of the arterial access site with a single six French suture‐mediated VCD is relatively easy, safe and efficient method for access site closure after TF‐TAVI which, along with ongoing profile reductions of TAVI devices, should further simplify and broaden the way toward a routine, completely percutaneous procedure. © 2012 Wiley Periodicals, Inc.
A Liquid–Liquid Biphasic Homogeneous Organocatalytic Aldol Protocol Based on the Use of a Silica Gel Bound Multilayered Ionic Liquid Phase
Authors: Montroni Elisa , Lombardo Marco , Quintavalla Arianna , Trombini Claudio , Gruttadauria Michelangelo , Giacalone Francesco
Published: May 2012

An innovative two stage liquid–liquid biphasic homogeneous protocol for the asymmetric organocatalytic aldol reaction is proposed, based on the use of the cis‐ion‐tagged proline 8 dissolved in the liquid film of a multilayered ionic liquid covalently bonded to silica gel 4. The resulting catalytically active material 9 is first soaked with cyclohexanone in the presence of water, resulting in a semi‐transparent gel, then the aldehyde is added and the mixture stirred at RT. In the first stage, 4 acts as a catalyst reservoir that delivers 8 to the cyclohexanone phase allowing the reaction to take place homogeneously. In the second stage, cyclohexanone is removed under vacuum and the resulting slurry is extracted with anhydrous diethylether. Now 4 acts as a catalyst sponge, redissolving 8. Product extraction is extremely selective; no trace of catalyst is detected in the product‐containing phase, and 9 can be easily reused several times with high cumulative productivity values (up to 523).
Surface and Bulk Approach to Time‐resolved Characterization of Heterogeneous Catalysts
Authors: Kubacka Anna , Iglesias‐Juez Ana , Martínez‐Arias Arturo , Di Michiel Marco , Newton Mark A. , Fernández‐García Marcos
Published: May 2012

The evolution of time‐resolved experiments, covering a multipurpose surface and bulk characterization of catalytic solids, during their preparation process and under reaction conditions, is presented. Particular emphasis is given to recent studies that attempt to unveil contemporary unresolved questions concerning the control of physicochemical properties of nanosolids, as well as the evolution of such solid materials under reactive atmospheres. To reach this goal, representative in situ and in operando works, using either modern (mostly synchrotron radiation based) approaches or multi‐technique methods (mainly, although not exclusively, X‐ray–vibrational coupling), and considering experiments in liquid and gas phase, as well as with amorphous, nanocrystalline and surface‐deposited materials, are reviewed.
Heterotermetallic Indium Lithium Halostannates: Low‐Temperature Single‐Source Precursors for Tin‐Rich Indium Tin Oxides and Their Application for Thin‐Film Transistors
Authors: Samedov Kerim , Aksu Yilmaz , Driess Matthias
Published: May 2012

The syntheses and structural elucidation of dimeric [Sn(OCyHex)2] (1), its corresponding (cyclohexoxy)alkalistannates(II) [{M(OCyHex)3Sn}2] (M=Li (2), Na (3), K (4)), and of the first heteroleptic heterotermetallic Li/In/Sn–haloalkoxide clusters [X2In{LiSn2(OCyHex)6}] (X=Br (5), Cl (6)) with a double seco‐norcubane core are reported. They represent suitable precursors for new amorphous indium tin oxide (ITO) materials as transparent conducting oxides with drastically reduced concentrations of expensive indium, while maintaining their high electrical performance. In fact, compounds 5 and 6 were successfully degraded under dry synthetic air at relatively low temperature, resulting in new semiconducting tin‐rich ITOs homogeneously dispersed in a tin oxide/lithium oxide matrix. The obtained particles were investigated and characterised by different analytical techniques, such as powder XRD, IR spectroscopy, SEM, TEM and energy‐dispersive X‐ray spectroscopy (EDX). The analytical data confirm that the final materials consist of tin‐containing indium oxide embedded in an amorphous tin oxide matrix. The typical broadening and shift of the observed indium oxide reflections to higher 2θ values in the powder XRD pattern clearly indicated that tin centres were successfully incorporated into the In2O3 lattice and partially occupied In3+ sites. Investigations by EDX mapping proved that Sn was homogeneously distributed in the final materials. Thin‐film field‐effect transistors (FETs) were fabricated by spin‐coating of silicon wafers with solutions of 5 in toluene and subsequent calcination under dry air (25–700 °C). The FETs prepared with precursor 5 exhibited excellent performances, as shown by a charge‐carrier mobility of 6.36×10−1 cm2 V−1 s (calcination at 250 °C) and an on/off current ratio of 106.
Determination of barriers to rotation of axially chiral 5‐methyl‐2‐(o‐aryl)imino‐3‐(o‐aryl)thiazolidine‐4‐ones
Authors: Erol Sule , Dogan Ilknur
Published: May 2012

Thermally interconvertible axially chiral 5‐methyl‐2‐(o‐aryl)imino‐3‐(o‐aryl)‐thiazolidine‐4‐ones have been synthesized diastereoselectively, and conformations of the major and minor enantiomeric pairs have been determined by 1H nuclear magnetic resonance. Chromatographic resolutions of each compound have been performed by enantioselective high‐performance liquid chromatography, and the barriers to rotation about the N3‐Caryl bond have been determined by following the thermal interconversion process of the major to minor isomers until equilibrium. The rotational barriers range from 96.2 to 115.2 kJ/mol, depending on the size of ortho substituent on N3‐aryl ring. Chirality 24:493–498, 2012. © 2012 Wiley Periodicals, Inc.
Vortex motion‐based particle swarm optimisation for energy consumption of alumina evaporation
Authors: Zhu Hongqiu , Chai Qinqin , Yang Chunhua , Wang Xiaoli
Published: May 2012

The aim of the alumina evaporation process is to improve the concentration of sodium aluminate solution by evaporating the excess water contained in the solution. The evaporation is achieved using heat from steam. Since steam consumption is the major operating costs, in this paper, we investigate an operation optimisation problem for the evaporation process to minimise steam consumption subject to a constraint on the particular quality of the final sodium aluminate solution. This paper proposes a new particle swarm optimisation (PSO) algorithm based on vortex motion to solve this optimisation problem. We demonstrate the effectiveness of the PSO algorithm on benchmark functions. We then apply it to a real industrial evaporation process, where the optimal results show that the steam consumption is considerably reduced. © 2012 Canadian Society for Chemical Engineering
Distribution of soap in a membrane reactor in the production of fame from waste cooking oil
Authors: Hasswa Raghda , Dubé Marc A. , Tremblay André Y.
Published: May 2012

A continuous‐flow membrane reactor was constructed for the production of fatty acid methyl ester (FAME) from waste vegetable oil with high free fatty acid (FFA) content. FAME was produced via base‐catalysed transesterification with methanol at two FFA levels: 4.8 and 10 mass%. The effect of the ceramic membrane pore size on the separation of soap and triglycerides from the FAME in the reactor was investigated. In all cases, the triglyceride was completely retained in the reactor, yielding free and total glycerine contents in the produced FAME significantly below the maximum limits of the ASTM D6751 standard. The soaps produced in the reaction mixture were not completely retained in the reactor and did not affect the FAME production process. © 2012 Canadian Society for Chemical Engineering
Modelling carbon dioxide solubility in ionic liquids
Authors: Mortazavi‐Manesh Soheil , Satyro Marco , Marriott Robert A.
Published: May 2012

Solubility information for CO2 in different ionic liquids, ILs, in part can potentially be used to select a specific IL for the separation of CO2 from hydrocarbon fluids. Unfortunately, not all CO2–IL systems have been experimentally described at similar temperatures and pressures; therefore, a direct comparison of performance by process simulation is not always possible. In the extreme cases, the design of a CO2 separation process may require predicting the CO2–IL equilibria for which there are no available solubility data. To address the need for this information, a semi‐empirical correlation was developed to estimate the dissolution of CO2 in CO2–IL solvent systems. The theoretical COSMO–RS calculation method was used to calculate the chemical potential of CO2 in a wide variety of ILs and the Soave–Redlich–Kwong equation was used to calculate the fugacity coefficient of the CO2 vapour phase. The model was correlated with available literature data, yielding an average error of AAR = 23% and small bias. © 2012 Canadian Society for Chemical Engineering
Reaction kinetics of 2‐((2‐aminoethyl) amino) ethanol in aqueous and non‐aqueous solutions using the stopped‐flow technique
Authors: Rayer Aravind V. , Henni Amr , Li Juelin
Published: May 2012

Observed pseudo‐first‐order rate constants (ko) for the reaction between CO2 and 2‐((2‐aminoethyl) amino) ethanol (AEEA) were measured using the stopped‐flow technique in an aqueous system at 298, 303, 308 and 313 K, and in non‐aqueous systems of methanol and ethanol at 293, 298, 303 and 308 K. Alkanolamine concentrations ranged from 9.93 to 80.29 mol m−3 for the aqueous system, 29.99–88.3 mol m−3 for methanol and 44.17–99.28 mol m−3 for ethanol. Experimentally obtained rate constants were correlated with two mechanisms. For both the aqueous‐ and non‐aqueous‐AEEA systems, the zwitterion mechanism with a fast deprotonation step correlated the data well as assessed by the reported statistical analysis. As expected, the reaction rate of CO2 in the aqueous‐AEEA system was found to be much faster than in methanol or ethanol. Compared to other promising amines and diamines studied using the stopped‐flow apparatus, the pseudo‐first‐order reaction rate constants were found to obey the following order: PZ (cyclic‐diamine) > EDA (diamine) > AEEA (diamine) > 3‐AP (primary amine) > MEA (primary amine) > EEA (primary amine) > MO (cyclic‐amine). The reaction rate constant of CO2 in aqueous‐AEEA was double that in aqueous‐MEA, and the difference increased with an increase in concentration. All reaction orders were practically unity. With a higher capacity for carbon dioxide and a higher reaction rate, AEEA could have been a good substitute to MEA if not for its high thermal degradation. AEEA kinetic behaviour is still of interest as a degradation product of MEA. © 2012 Canadian Society for Chemical Engineering
Adsorption microcalorimetry applied to the characterisation of adsorbents for CO2 capture
Authors: da Silva F. Wilton Miranda , Maia Débora A. Soares , Oliveira Ronan S. , Moreno‐Piraján Juan Carlos , Sapag Karim , Cavalcante Célio L. , Zgrablich Giorgio , Azevedo Diana C. S.
Published: May 2012

The present work presents the design, assembly and experimental validation of a microcalorimetric device coupled to a volumetric adsorption setup applied to the characterisation of adsorbents for carbon dioxide (CO2) capture. Three adsorbents were evaluated for CO2 adsorption at 273 K in the pressure range of vacuum to 101 kPa. The data for CO2 on zeolite 13X agreed well with the available data reported in the literature, thus validating the device, which also provided reproducible results with an activated carbon sample. For the amine‐modified zeolite, the differential enthalpy at lower coverage was increased by a factor of 1.7 as compared to the zeolite matrix. This points out to the potential of such technique to characterise heterogeneities introduced by amine impregnation. However, the adsorption uptake was decreased by factor of 2.7 at 101 kPa. This fact suggests that amino groups may be blocking some physisorption sites, leading to restricted chemisorption on the outer surface. Thus, the main novelty of this study is the simultaneous measurement of adsorption isotherms and respective differential enthalpy curves for amine‐impregnated adsorbents, which may be considered a fingerprint of the modified surface chemistry. This work has been carried out in the framework of a cooperation project between three South American universities and is part of the effort to develop and fully characterise adsorbent materials intended for CO2 capture. © 2012 Canadian Society for Chemical Engineering
Prediction of induction time for natural gas components during gas hydrate formation in the presence of kinetic hydrate inhibitors in a flow mini‐loop apparatus
Authors: Talaghat Mohammad Reza
Published: May 2012

The objective of this work is the prediction of induction time (ti) for simple gas hydrate formation in the presence or absence of kinetic hydrate inhibitors at various conditions based on the Kashchiev and Firoozabadi model in a flow mini‐loop apparatus. For this purpose, the ti model is developed for simple gas hydrate formation in batch system for natural gas components during hydrate formation in a flow mini‐loop apparatus. A laboratory flow mini‐loop apparatus is designed and built up to measure the ti for simple gas hydrate formation when a hydrate former (such as C1, C3, CO2 and i‐C4) is contacted with water in the absence or presence of dissolved inhibitor, such as poly vinylpyrrolidone, PVCap and L‐tyrosine. In each experiment, a water blend saturated with pure gas is circulated up to a required pressure. Pressure is maintained at a constant value during experimental runs by means of the required gas make‐up. The average absolute deviation (AAD) of the predicted ti values from the corresponding experimental data are found to be about 11% and 9.4% for gas hydrate formation ti in the presence or absence of kinetic hydrate inhibitors, respectively. © 2012 Canadian Society for Chemical Engineering
Discovery, Synthesis, and in vitro Evaluation of West Nile Virus Protease Inhibitors Based on the 9,10‐Dihydro‐3H,4aH‐1,3,9,10a‐tetraazaphenanthren‐4‐one Scaffold
Authors: Samanta Sanjay , Cui Taian , Lam Yulin
Published: May 2012

West Nile virus (WNV), a member of the Flaviviridae family, is a mosquito‐borne pathogen that causes a great number of human infections each year. Neither vaccines nor antiviral therapies are currently available for human use. In this study, a WNV NS2B–NS3 protease inhibitor with a 9,10‐dihydro‐3H,4aH‐1,3,9,10a‐tetraazaphenanthren‐4‐one scaffold was identified by screening a small library of non‐peptidic compounds. This initial hit was optimized by solution‐phase synthesis and screening of a focused library of compounds bearing this scaffold. This led to the identification of a novel, uncompetitive inhibitor (1a40, IC50=5.41±0.45 μM) of WNV NS2B–NS3 protease. Molecular docking of this chiral compound onto the WNV protease indicates that the S enantiomer of 1a40 appears to interfere with the productive interactions between the NS2B cofactor and the NS3 protease domain; (S)‐1a40 is a preferred isomer for inhibition of WNV NS3 protease.
On the Configuration of Supercapacitors for Maximizing Electrochemical Performance
Authors: Zhang Jintao , Zhao X. S.
Published: May 2012

Supercapacitors, which are attracting rapidly growing interest from both academia and industry, are important energy‐storage devices for acquiring sustainable energy. Recent years have seen a number of significant breakthroughs in the research and development of supercapacitors. The emergence of innovative electrode materials (e.g., graphene) has clearly provided great opportunities for advancing the science in the field of electrochemical energy storage. Conversely, smart configurations of electrode materials and new designs of supercapacitor devices have, in many cases, boosted the electrochemical performance of the materials. We attempt to summarize recent research progress towards the design and configuration of electrode materials to maximize supercapacitor performance in terms of energy density, power density, and cycle stability. With a brief description of the structure, energy‐storage mechanism, and electrode configuration of supercapacitor devices, the design and configuration of symmetric supercapacitors are discussed, followed by that of asymmetric and hybrid supercapacitors. Emphasis is placed on the rational design and configuration of supercapacitor electrodes to maximize the electrochemical performance of the device.
Dialkylimidazolium Ionic Liquids Hydrolyze Cellulose Under Mild Conditions
Authors: Gazit Oz M. , Katz Alexander
Published: May 2012

The average molecular weight of cellulose derived from filter paper, poplar, and Avicel decreases by up to two orders of magnitude during typical mild dissolution protocols using ionic liquids (ILs). About an order of magnitude greater cellulose depolymerization rate during ionic liquid dissolution occurs in 1‐butyl‐3‐methylimidazolium chloride (BmimCl) and 1‐ethyl‐3‐methylimidazolium chloride (EmimCl) compared to 1‐ethyl‐3‐methylimidazolium acetate (EmimOAc), and, unintuitively, greater IL purity results in greater cellulose depolymerization. The following data support the mechanism of cellulose hydrolysis to be acid‐catalyzed: (i) increase in number of reducing ends following cellulose dissolution in IL; (ii) addition of N‐methylimidazolium base suppresses cellulose depolymerization during dissolution in IL; (iii) small amounts of glucose and traces of hydroxymethyl furfural are present following cellulose dissolution in IL. The acid is presumably synthesized via IL decomposition to generate a carbene and proton, consistent with hypothesis derived from molecular modeling. Titration experiments conducted here measure the amount of acid synthesized to be in the 4000 ppm range for high‐purity BmimCl IL during mild processing conditions for cellulose dissolution. This data is relevant for understanding the extent of IL decomposition during biomass dissolution.