bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of extrusion process, type and content of clays, and foaming process on the clay exfoliation in HMS PP composites
Authors: Laguna‐Gutierrez Ester , Van Hooghten Rob , Moldenaers Paula , Angel Rodriguez‐Perez Miguel
Published: August 2015

The use of a high melt strength polypropylene (HMS PP) matrix reinforced with layered clays could be very useful to improve the properties of materials produced with processes involving melt stretching, like foaming. The control of the particles structure, that is, the degree of exfoliation and the clay distribution in the polymeric matrix, is the key to achieve the desired properties. In this study, the effects of the extrusion process, the clay type and content, and the foaming process on the morphology of different HMS PP based composites are studied. Both, natural and organomodified clays were used. The extrusion process has a negative effect in the composites containing natural clays as their interlayer distance decreases as the number of extrusion cycles increases. On the contrary, this process improves the intercalation of the organomodified clays. However, in both composites the interlayer spacing decreases when the clay content increases. While a percolated network is formed in the composites containing organomodified clays, no network is formed with the natural clays. Finally, the effect of the foaming process has also been analyzed. The Improved Compression Moulding (ICM) route was used to produce the foamed materials. This technique subjects the materials only to a temperature and a pressure gradient without applying any other external forces that could contribute to the clay exfoliation. In this way, only the effects of foaming and melt stretching are observed. In both composites, an increase in the interlayer distance is observed when the materials are foamed. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42828.
ENVIRONMENTAL EFFECTS ON SUPEROXIDE DISMUTASE AND CATALASE ACTIVITY AND EXPRESSION IN HONEY BEE
Authors: Nikolić Tatjana V. , Purać Jelena , Orčić Snežana , Kojić Danijela , Vujanović Dragana , Stanimirović Zoran , Gržetić Ivan , Ilijević Konstantin , Šikoparija Branko , Blagojević Duško P.
Published: August 2015

Understanding the cellular stress response in honey bees will significantly contribute to their conservation. The aim of this study was to analyze the response of the antioxidative enzymes superoxide dismutase and catalase in honey bees related to the presence of toxic metals in different habitats. Three locations were selected: (i) Tunovo on the mountain Golija, as control area, without industry and large human impact, (ii) Belgrade as urban area, and (iii) Zajača, as mining and industrial zone. Our results showed that the concentrations of lead (Pb) in whole body of bees vary according to habitat, but there was very significant increase of Pb in bees from investigated industrial area. Bees from urban and industrial area had increased expression of both Sod1 and Cat genes, suggesting adaptation to increased oxidative stress. However, in spite increased gene expression, the enzyme activity of catalase was lower in bees from industrial area suggesting inhibitory effect of Pb on catalase.
Convicts and commodities: An archaeological approach to the economic value of the Western Australian penal system
Authors: Haast Alyce
Published: August 2015

The introduction of the convict system in 1850 into the Western Australian (WA) economy resulted in a large injection of capital into the colony, the dissemination of which cannot be overlooked when considering the transformative effect of the convict system. This injection resulted from the purchase of goods and services by the penal system that ultimately transferred money from the British Crown into the local market. For this paper, historical and archaeological data was used to develop an understanding of the breakdown of spending by the penal system, and to consider how the circumstance of individual aspects of the penal system impacted purchasing choices, and subsequently benefitted the local market. Using artefacts recovered from two sites within Fremantle Prison, one representing institutional purchases and the other relating to a wage earner, it was possible the test the variation in economic impact of spending given institutional circumstance. By considering whether purchases represented local commodities or imports, it was possible to see how capital transferred into the local economy and how much of that spending leaked out through imports. In doing this, the analysis highlighted the varying benefit of the capital injected by the penal system related to circumstance and the value of considering the penal system as an elaborate entity.
Brief Report: Cartilage Thickness Change as an Imaging Biomarker of Knee Osteoarthritis Progression: Data From the Foundation for the National Institutes of Health Osteoarthritis Biomarkers Consortium
Authors: Eckstein F. , Collins J. E. , Nevitt M. C. , Lynch J. A. , Kraus V. B. , Katz J. N. , Losina E. , Wirth W. , Guermazi A. , Roemer F. W. , Hunter D. J. ,   for the FNIH OA Biomarkers Consortium
Published: August 2015

Objective

To investigate the association of cartilage thickness change over 24 months, as determined by magnetic resonance imaging (MRI), with knee osteoarthritis (OA) progression at 24–48 months.

Methods

This nested case–control study included 600 knees with a baseline Kellgren/Lawrence (K/L) grade of 1–3 from 600 Osteoarthritis Initiative (OAI) participants. Case knees (n = 194) had both medial tibiofemoral radiographic joint space loss (≥0.7 mm) and a persistent increase in the Western Ontario and McMaster Universities Osteoarthritis Index pain score (≥9 on a 0–100 scale) 24–48 months from baseline. Control knees (n = 406) included 200 with neither radiographic nor pain progression, 103 with radiographic progression only, and 103 with pain progression only. Medial and lateral femorotibial cartilage was segmented from sagittal 3T MRIs at baseline, 12 months, and 24 months. Logistic regression was used to assess the association of change in cartilage thickness, with a focus on the central medial femorotibial compartment, and OA progression.

Results

Central medial femorotibial compartment thickness loss was significantly associated with case status, with an odds ratio (OR) of 1.9 (95% confidence interval [95% CI] 1.6–2.3) (P < 0.0001). Association with case status reached P < 0.05 for both the central femur (OR 1.8 [95% CI 1.5–2.2]) and the central tibia (OR 1.6 [95% CI 1.3–1.9]). Lateral femorotibial compartment cartilage thickness loss, in contrast, was not significantly associated with case status. A reduction in central medial femorotibial compartment cartilage thickness was strongly associated with radiographic progression (OR 4.0 [95% CI 2.9–5.3]; P < 0.0001) and only weakly associated with pain progression (OR 1.3 [95% CI 1.1–1.6]; P < 0.01).

Conclusion

Our findings indicate that loss of medial femorotibial cartilage thickness over 24 months is associated with the combination of radiographic and pain progression in the knee, with a stronger association for radiographic progression.
Latent Cytomegalovirus Infection in Rheumatoid Arthritis and Increased Frequencies of Cytolytic LIR‐1+CD8+ T Cells
Authors: Rothe Kathrin , Quandt Dagmar , Schubert Kristin , Rossol Manuela , Klingner Maria , Jasinski‐Bergner Simon , Scholz Roger , Seliger Barbara , Pierer Matthias , Baerwald Christoph , Wagner Ulf
Published: August 2015

Objective

Leukocyte immunoglobulin‐like receptor 1 (LIR‐1) is up‐regulated by cytomegalovirus (CMV), which in turn, has been associated with premature aging and more severe joint disease in patients with rheumatoid arthritis (RA). The aim of this study was to investigate the expression and functional significance of LIR‐1 in CMV‐positive RA patients.

Methods

We determined the phenotype, cytolytic potential, CMV‐specific proliferation, and HLA–G–triggered, LIR‐1–mediated inhibition of interferon‐γ secretion of LIR‐1+ T cells in RA patients and healthy controls.

Results

We found increased frequencies of CD8+ T cells with CMV pp65–specific T cell receptors in CMV‐positive RA patients as compared to CMV‐positive healthy controls. CMV‐specific CD8+ T cells in these patients were preferentially LIR‐1+ and exhibited a terminally differentiated polyfunctional phenotype. The numbers of LIR‐1+CD8+ T cells increased with age and disease activity, and showed high levels of reactivity to CMV antigens. Ligation of LIR‐1 with soluble HLA–G molecules in vitro confirmed an inhibitory role of the molecule when expressed on CD8+ T cells in RA patients.

Conclusion

We propose that latent CMV infection in the context of a chronic autoimmune response induces the recently described “chronic infection phenotype” in CD8+ T cells, which retains anti‐infectious effector features while exhibiting autoreactive cytolytic potential. This response is likely dampened by LIR‐1 to avoid overwhelming immunopathologic changes in the setting of the autoimmune disease RA. The known deficiency of soluble HLA–G in RA and the observed association of LIR‐1 expression with disease activity suggest, however, that LIR‐1+ T cells are insufficiently controlled in RA and are still likely to be involved in the pathogenesis of the disease.
Sample Size Calculations for Detecting Disease‐Modifying Osteoarthritis Drug Effects on Knee Replacement Incidence in Clinical Trials: Data From the Osteoarthritis Initiative
Authors: Ried Janina S. , Flechsenhar Klaus , Bartnik Eckart , Crowther Daniel , Dietrich Axel , Eckstein Felix
Published: August 2015

Objective

To evaluate the extent to which the current designs of clinical trials in knee osteoarthritis (OA) permit detection of a therapeutic effect of disease‐modifying OA drugs (DMOADs) on the incidence of knee replacement, and to provide estimates of the required sample sizes.

Methods

We selected distinct subcohorts of the Osteoarthritis Initiative (OAI), based on available information on eligibility criteria for clinical knee OA trials (ClinicalTrials.gov) and additional subcohorts stratified for age, sex, and the severity of radiographic OA. The observed incidence of knee replacement in these OAI subcohorts was used to estimate the expected incidence of knee replacement in the control group of a clinical trial. Based on this estimate, the sample sizes required to detect hypothetical treatment effects on the incidence of knee replacement were calculated, assuming observation periods of 2, 5, or 7 years.

Results

The cumulative knee replacement incidence rates in the OAI subcohorts ranged from 0.9% to 12.9%. The corresponding sample sizes required to detect 50% improvement by the DMOAD, with a power of 80% and 95% confidence, were 5,459 and 362, respectively. Including only women with advanced age and radiographic OA increased the incidence of knee replacement and decreased the required sample size.

Conclusion

The sample sizes that are commonly used in clinical trials do not enable the effects of a DMOAD on incident knee replacement to be detected with sufficient power and confidence. The estimated incidence rates of knee replacement and the corresponding sample sizes are important for informing the design of trials for disease course–modifying effects as well as for socioeconomic evaluation of a DMOAD in terms of preventing knee replacement.
Takayasu Arteritis and Pregnancy
Authors: Comarmond C. , Mirault T. , Biard L. , Nizard J. , Lambert M. , Wechsler B. , Hachulla E. , Chiche L. , Koskas F. , Gaudric J. , Cluzel P. , Messas E. , Resche‐Rigon M. , Piette J. C. , Cacoub P. , Saadoun D. ,   for the French Takayasu Network
Published: August 2015

Objective

To assess the relationship between Takayasu arteritis (TAK) and pregnancy outcome.

Methods

This study included 240 pregnancies in 96 patients fulfilling the American College of Rheumatology 1990 criteria for the classification of TAK and/or the 1994 Chapel Hill Consensus Conference nomenclature/criteria for vasculitis. We analyzed obstetric and maternal outcomes in women who were pregnant before and/or at the same time as or after TAK diagnosis. We assessed factors associated with complicated pregnancy.

Results

One hundred forty‐two pregnancies occurred in 52 patients before TAK diagnosis (median age at pregnancy 26 years [interquartile range 23–30 years]), and 98 pregnancies occurred in 52 patients concomitant with or after TAK diagnosis (median age at pregnancy 28 years [interquartile range 26–31 years]). Pregnancies concomitant with or after TAK diagnosis had a 13‐fold higher rate of obstetric complications compared to pregnancies before TAK diagnosis (odds ratio 13 [95% confidence interval 5–33], P < 0.0001). TAK was associated with a 40% frequency of obstetric complications, including preeclampsia/eclampsia (24 pregnancies [24%]), premature delivery (8 pregnancies [8%]), and intrauterine fetal growth restriction or death (5 pregnancies [5%]). Maternal complications of TAK occurred during 39% of pregnancies and included mainly new‐onset or worsening hypertension (26 pregnancies [27%]). In multivariate analysis, smoking (odds ratio 6.15 [95% confidence interval 1.31–28.8]) and disease activity of TAK (a National Institutes of Health score of >1) (odds ratio 28.7 [95% confidence interval 7.89–104.7]) were independently associated with obstetric and maternal complications.

Conclusion

TAK negatively affects pregnancy outcomes. Disease activity increases the risk of obstetric and maternal complications, mainly due to arterial hypertension.
Type I Interferon Inhibition of MicroRNA‐146a Maturation Through Up‐Regulation of Monocyte Chemotactic Protein–Induced Protein 1 in Systemic Lupus Erythematosus
Authors: Qu Bo , Cao Jianchang , Zhang Feifei , Cui Huijuan , Teng Jialin , Li Jia , Liu Zheng , Morehouse Chris , Jallal Bahija , Tang Yuanjia , Guo Qiang , Yao Yihong , Shen Nan
Published: August 2015

Objective

Systemic lupus erythematosus (SLE) is characterized by the uncontrolled production of inflammatory cytokines, among which type I interferon (IFN) is recognized as a crucial pathogenic factor. The expression of microRNA‐146a (miR‐146a) is reduced in the white blood cells of SLE patients and accounts for their overactivated inflammatory responses. However, the mechanism of the reduction of miR‐146a is still not fully understood. This study was undertaken to test whether the key pathogenic cytokine, type I IFN, is responsible for the dysregulation of miR‐146a in SLE.

Methods

Gene and protein expression was measured in all cells by reverse transcription–quantitative polymerase chain reaction, Northern blotting, or Western blotting. In THP‐1 cells, expression of monocyte chemotactic protein–induced protein 1 (MCPIP‐1) was knocked down with a lentivirus encoding a short hairpin RNA targeting MCPIP1. The cells were pretreated with type I IFN and assessed for gene expression levels of miR‐146a. White blood cells from patients with SLE were analyzed for the expression of the IFN‐inducible genes MCPIP1 and miR‐146a, and the gene expression data were compared for correlation.

Results

Pretreatment of THP‐1 cells with type I IFN attenuated the induction of miR‐146a posttranscriptionally, by down‐regulating the expression of pre‐miR‐146a but not pri‐miR‐146a or its original unspliced transcript. Expression of MCPIP‐1, which was enhanced by type I IFN, was found to be responsible for the inhibition of miR‐146a. In white blood cells from patients with SLE, MCPIP1 expression was elevated, and its expression correlated positively with the IFN score and negatively with the miR‐146a transcript level.

Conclusion

Type I IFN inhibits the maturation of miR‐146a through the up‐regulation of MCPIP‐1, and thus contributes to the uncontrolled inflammation and excessive inflammatory gene expression in SLE.
Rate and Clinical Presentation of Macrophage Activation Syndrome in Patients With Systemic Juvenile Idiopathic Arthritis Treated With Canakinumab
Authors: Grom Alexei A. , Ilowite Norman T. , Pascual Virginia , Brunner Hermine I. , Martini Alberto , Lovell Daniel , Ruperto Nicolino ,   for the Paediatric Rheumatology International Trials Organisation and the Pediatric Rheumatology Collaborative Study Group, Leon Karolynn , Lheritier Karine , Abrams Ken
Published: August 2015

Objective

In pivotal trials, canakinumab has been shown to be effective in the treatment of systemic juvenile idiopathic arthritis (JIA), but reported adverse events have included macrophage activation syndrome (MAS). This study was undertaken to assess the impact of canakinumab on MAS incidence.

Methods

An independent MAS Adjudication Committee (MASAC), consisting of 3 of the authors, was convened, and a search of databases from clinical studies of canakinumab treatment in systemic JIA was performed using MASAC‐specified adverse event terms to identify potential MAS events. These were then adjudicated as “probable MAS,” “possible MAS,” or “MAS unlikely,” using criteria developed by the MASAC. MAS rates were expressed as numbers of cases per 100 patient‐years.

Results

Of 72 potential MAS cases identified, 21 events (19 with canakinumab treatment; 2 with placebo treatment) in 19 patients were adjudicated as being probable MAS and 10 events in 9 patients as being possible MAS. Systemic JIA was well controlled in the majority of canakinumab‐treated patients at the time of MAS. The time period between initiation of canakinumab treatment and onset of MAS ranged from 3 to 1,358 days (median 292 days). When the rates of probable MAS events were compared between canakinumab‐treated patients (2.8 per 100 patient‐years) and placebo‐treated patients (7.7 per 100 patient‐years), the difference was not significant (−4.9 [95% confidence interval −15.6, 5.9]). There were 3 deaths due to MAS‐related complications (2 in patients receiving canakinumab; 1 in a patient receiving placebo); full recovery was reported in all other patients. Infections were the most common trigger of MAS, and the clinical features of MAS were not modified by canakinumab.

Conclusion

Canakinumab does not have a significant effect on MAS risk or its clinical features in patients with systemic JIA. Infections are the most common trigger, and MAS occurs even in patients whose systemic JIA is well controlled with this treatment.
Phenotypic, Functional, and Gene Expression Profiling of Peripheral CD45RA+ and CD45RO+ CD4+CD25+CD127low Treg Cells in Patients With Chronic Rheumatoid Arthritis
Authors: Walter Gina J. , Fleskens Veerle , Frederiksen Klaus S. , Rajasekhar Megha , Menon Bina , Gerwien Jens G. , Evans Hayley G. , Taams Leonie S.
Published: August 2015

Objective

Conflicting evidence exists regarding the suppressive capacity of Treg cells in the peripheral blood (PB) of patients with rheumatoid arthritis (RA). The aim of this study was to determine whether Treg cells are intrinsically defective in RA.

Methods

Using a range of assays on PB samples from patients with chronic RA and healthy controls, CD3+CD4+CD25+CD127low Treg cells from the CD45RO+ or CD45RA+ T cell compartments were analyzed for phenotype, cytokine expression (ex vivo and after in vitro stimulation), suppression of Teff cell proliferation and cytokine production, suppression of monocyte‐derived cytokine/chemokine production, and gene expression profiles.

Results

No differences between RA patients and healthy controls were observed with regard to the frequency of Treg cells, ex vivo phenotype (CD4, CD25, CD127, CD39, or CD161), or proinflammatory cytokine profile (interleukin‐17 [IL‐17], interferon‐γ [IFNγ], or tumor necrosis factor [TNF]). FoxP3 expression was slightly increased in Treg cells from RA patients. The ability of Treg cells to suppress the proliferation of T cells or the production of cytokines (IFNγ or TNF) upon coculture with autologous CD45RO+ Teff cells and monocytes was not significantly different between RA patients and healthy controls. In PB samples from some RA patients, CD45RO+ Treg cells showed an impaired ability to suppress the production of certain cytokines/chemokines (IL‐1β, IL‐1 receptor antagonist, IL‐7, CCL3, or CCL4) by autologous lipopolysaccharide‐activated monocytes. However, this was not observed in all patients, and other cytokines/chemokines (TNF, IL‐6, IL‐8, IL‐12, IL‐15, or CCL5) were generally suppressed. Finally, gene expression profiling of CD45RA+ or CD45RO+ Treg cells from the PB revealed no statistically significant differences between RA patients and healthy controls.

Conclusion

Our findings indicate that there is no global defect in either CD45RO+ or CD45RA+ Treg cells in the PB of patients with chronic RA.
Selective Loss of Signaling Lymphocytic Activation Molecule Family Member 4–Positive CD8+ T Cells Contributes to the Decreased Cytotoxic Cell Activity in Systemic Lupus Erythematosus
Authors: Kis‐Toth Katalin , Comte Denis , Karampetsou Maria P. , Kyttaris Vasileios C. , Kannan Lakshmi , Terhorst Cox , Tsokos George C.
Published: August 2015

Objective

Engagement of signaling lymphocytic activation molecule family member 4 (SLAMF4; CD244, 2B4) by its ligand SLAMF2 (CD48) modulates the function and expansion of both natural killer cells and a subset of cytotoxic CD8+ T cells. Because the cytotoxicity of CD8+ T lymphocytes isolated from patients with systemic lupus erythematosus (SLE) is known to be impaired, the aim of this study was to assess whether the expression and function of the checkpoint regulator SLAMF4 are altered on CD8+ T cells from patients with SLE.

Methods

The expression of SLAMF4 by T cells from healthy donors and patients with SLE was determined by quantitative polymerase chain reaction and flow cytometry. T cells were activated with anti‐CD3 antibody, and degranulation activity was monitored by the surface expression of lysosome‐associated membrane protein 1 (LAMP‐1; CD107a). The SLAMF4+ and SLAMF4− CD8+ T cell subpopulations were characterized by LAMP‐1, perforin, and granzyme B expression and viral peptide–induced proliferation.

Results

SLAMF4 gene and surface protein expression was down‐regulated in CD8+ T cells from SLE patients compared with that in cells obtained from healthy donors. Importantly, SLE patients had significantly fewer SLAMF4+ CD8+ T cells compared with healthy donors. SLAMF4− CD8+ T cells from SLE patients had a decreased cytotoxic capacity and decreased proliferative responses to viral peptides. The loss of memory SLAMF4+ CD8+ T cells in SLE patients was linked to the fact that these cells have an increased propensity to lose CD8 expression and become double‐negative T cells.

Conclusion

A selective loss of SLAMF4+ CD8+ T cells contributes to the compromised ability of T cells from patients with SLE to fight infection.
Selective Inhibition of Membrane Type 1 Matrix Metalloproteinase Abrogates Progression of Experimental Inflammatory Arthritis: Synergy With Tumor Necrosis Factor Blockade
Authors: Kaneko Kazuyo , Williams Richard O. , Dransfield Daniel T. , Nixon Andrew E. , Sandison Ann , Itoh Yoshifumi
Published: August 2015

Objective

In rheumatoid arthritis (RA), destruction of articular cartilage by the inflamed synovium is considered to be driven by increased activities of proteolytic enzymes, including matrix metalloproteinases (MMPs). The purpose of this study was to investigate the therapeutic potential of selective inhibition of membrane type 1 MMP (MT1‐MMP) and its combination with tumor necrosis factor (TNF) blockage in mice with collagen‐induced arthritis (CIA).

Methods

CIA was induced in DBA/1 mice by immunization with bovine type II collagen. From the onset of clinical arthritis, mice were treated with MT1‐MMP selective inhibitory antibody DX‐2400 and/or TNFR‐Fc fusion protein. Disease progression was monitored daily, and serum, lymph nodes, and affected paws were collected at the end of the study for cytokine and histologic analyses. For in vitro analysis, bone marrow–derived macrophages were stimulated with lipopolysaccharide for 24 hours in the presence of DX‐2400 and/or TNFR‐Fc to analyze cytokine production and phenotype.

Results

DX‐2400 treatment significantly reduced cartilage degradation and disease progression in mice with CIA. Importantly, when combined with TNF blockade, DX‐2400 acted synergistically, inducing long‐term benefit. DX‐2400 also inhibited the up‐regulation of interleukin‐12 (IL‐12)/IL‐23 p40 via polarization toward an M2 phenotype in bone marrow–derived macrophages. Increased production of IL‐17 induced by anti‐TNF, which correlated with an incomplete response to anti‐TNF, was abrogated by combined treatment with DX‐2400 in CIA.

Conclusion

Targeting MT1‐MMP provides a potential strategy for joint protection, and its combination with TNF blockade may be particularly beneficial in RA patients with an inadequate response to anti‐TNF therapy.
Fetal microchimerism and maternal health: A review and evolutionary analysis of cooperation and conflict beyond the womb
Authors: Boddy Amy M. , Fortunato Angelo , Wilson Sayres Melissa , Aktipis Athena
Published: August 2015

The presence of fetal cells has been associated with both positive and negative effects on maternal health. These paradoxical effects may be due to the fact that maternal and offspring fitness interests are aligned in certain domains and conflicting in others, which may have led to the evolution of fetal microchimeric phenotypes that can manipulate maternal tissues. We use cooperation and conflict theory to generate testable predictions about domains in which fetal microchimerism may enhance maternal health and those in which it may be detrimental. This framework suggests that fetal cells may function both to contribute to maternal somatic maintenance (e.g. wound healing) and to manipulate maternal physiology to enhance resource transmission to offspring (e.g. enhancing milk production). In this review, we use an evolutionary framework to make testable predictions about the role of fetal microchimerism in lactation, thyroid function, autoimmune disease, cancer and maternal emotional, and psychological health.

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Using Video Feedback to Improve Martial Arts Performance
Authors: BenitezSantiago Angela , Miltenberger Raymond G.
Published: August 2015

This study used video feedback to enhance the martial arts performance of capoeira, an Afro‐Brazilian martial art that utilizes acrobatic movements (revesado, au de costa, and macaco). A multiple baseline across behaviors was used for five participants where baseline conditions consisted of standard coaching. The intervention consisted of video feedback, in which the participants were filmed attempting a movement and immediately viewed the video afterwards, while receiving positive and corrective feedback from the instructor. The target behaviors were scored on a 15‐item checklist, resulting in a percentage correct. A second video feedback condition similar to the first was also introduced to some participants, in which participants practiced the movements with live feedback before being filmed again. Results show that the video feedback conditions increased performance over baseline in most cases. Copyright © 2015 John Wiley & Sons, Ltd.
Microarray profiling of preselected CHO host cell subclones identifies gene expression patterns associated with in‐creased production capacity
Authors: Harreither Eva , Hackl Matthias , Pichler Johannes , Shridhar Smriti , Auer Norbert , Łabaj Pawelł P. , Scheideler Marcel , Karbiener Michael , Grillari Johannes , Kreil David P. , Borth Nicole
Published: August 2015

Over the last three decades, product yields from CHO cells have increased dramatically, yet specific productivity (qP) remains a limiting factor. In a previous study, using repeated cell‐sorting, we have established different host cell subclones that show superior transient qP over their respective parental cell lines (CHO‐K1, CHO‐S). The transcriptome of the resulting six cell lines in different biological states (untransfected, mock transfected, plasmid transfected) was first explored by hierarchical clustering and indicated that gene activity associated with increased qP did not stem from a certain cellular state but seemed to be inherent for a high qP host line. We then performed a novel gene regression analysis identifying drivers for an increase in qP. Genes significantly implicated were first systematically tested for enrichment of GO terms using a Bayesian approach incorporating the hierarchical structure of the GO term tree. Results indicated that specific cellular components such as nucleus, ER, and Golgi are relevant for cellular productivity. This was complemented by targeted GSA that tested functionally homogeneous, manually curated subsets of KEGG pathways known to be involved in transcription, translation, and protein processing. Significantly implicated pathways included mRNA surveillance, proteasome, protein processing in the ER and SNARE interactions in vesicular transport.
Development and validation of a rapid LC‐MS/MS method to quantify letrozole in human plasma and its application to therapeutic drug monitoring
Authors: Shao Rong , Yu Ling‐yan , Lou Hong‐gang , Ruan Zou‐rong , Jiang Bo , Chen Jin‐liang
Published: August 2015

A selective, rapid, and sensitive liquid chromatography–tandem mass spectrometry(LC‐MS/MS) method was developed and validated for the determination of letrozole (LTZ) in human plasma, using anastrozole as internal standard (IS). Sample preparation was performed by one‐step protein precipitation with methanol. The analyte and IS were chromatographed on a reversed‐phase YMC‐ODS‐C18 column (2.0 × 100 mm i.d., 3 µm) with a flow rate of 0.3 mL/min. The mobile phase consisted of water containing 0.1% formic acid (v/v) and methanol containing 0.1% formic acid (v/v). The mass spectrometer was operated in selected reaction monitoring mode through electrospray ionization ion mode using the transitions of m/z 286.2 → 217.1 for LTZ and m/z 294.1 → 225.1 for IS, respectively. The method was validated for selectivity, linearity, lower limit of quantitation, precision, accuracy, matrix effects and stability in accordance with the US Food and Drug Administration guidelines. Linear calibration curves were 1.0–60.0 ng/mL. Intra‐ and inter‐batch precision (CV) for LTZ were <9.34%, and the accuracy ranged from 97.43 to 105.17%. This method was successfully used for the analysis of samples from patients treated with LTZ in the dose of 2.5 mg/day. It might be suitable for therapeutic drug monitoring of these patients and contribute to predict the risk of adverse reactions. Copyright © 2015 John Wiley & Sons, Ltd.
Application of high‐throughput mini‐bioreactor system for systematic scale‐down modeling, process characterization, and control strategy development
Authors: Janakiraman Vijay , Kwiatkowski Chris , Kshirsagar Rashmi , Ryll Thomas , Huang Yao‐Ming
Published: August 2015

High‐throughput systems and processes have typically been targeted for process development and optimization in the bioprocessing industry. For process characterization, bench scale bioreactors have been the system of choice. Due to the need for performing different process conditions for multiple process parameters, the process characterization studies typically span several months and are considered time and resource intensive. In this study, we have shown the application of a high‐throughput mini‐bioreactor system viz. the Advanced Microscale Bioreactor (ambr15TM), to perform process characterization in less than a month and develop an input control strategy. As a pre‐requisite to process characterization, a scale‐down model was first developed in the ambr system (15 mL) using statistical multivariate analysis techniques that showed comparability with both manufacturing scale (15,000 L) and bench scale (5 L). Volumetric sparge rates were matched between ambr and manufacturing scale, and the ambr process matched the pCO2 profiles as well as several other process and product quality parameters. The scale‐down model was used to perform the process characterization DoE study and product quality results were generated. Upon comparison with DoE data from the bench scale bioreactors, similar effects of process parameters on process yield and product quality were identified between the two systems. We used the ambr data for setting action limits for the critical controlled parameters (CCPs), which were comparable to those from bench scale bioreactor data. In other words, the current work shows that the ambr15TM system is capable of replacing the bench scale bioreactor system for routine process development and process characterization. © 2015 American Institute of Chemical Engineers Biotechnol. Prog., 31:1623–1632, 2015
Catalysis of an Essential Step in Vitamin B2 Biosynthesis by a Consortium of Broad Spectrum Hydrolases
Authors: Sarge Sonja , Haase Ilka , Illarionov Boris , Laudert Dietmar , Hohmann Hans‐Peter , Bacher Adelbert , Fischer Markus
Published: August 2015

An enzyme catalysing the essential dephosphorylation of the riboflavin precursor, 5‐amino‐6‐ribitylamino‐2,4(1H,3H)‐pyrimidinedione 5′‐phosphate (6), was purified about 800‐fold from a riboflavin‐producing Bacillus subtilis strain, and was assigned as the translation product of the ycsE gene by mass spectrometry. YcsE is a member of the large haloacid dehalogenase (HAD) superfamily. The recombinant protein was expressed in Escherichia coli. It catalyses the hydrolysis of 6 (vmax, 12 μmol mg−1 min−1; KM, 54 μm) and of FMN (vmax, 25 μmol mg−1 min−1; KM, 135 μm). A ycsE deletion mutant of B. subtilis was not riboflavin dependent. Two additional proteins (YwtE, YitU) that catalyse the hydrolysis of 6 at appreciable rates were identified by screening 13 putative HAD superfamily members from B. subtilis. The evolutionary processes that have resulted in the handling of an essential step in the biosynthesis of an essential cofactor by a consortium of promiscuous enzymes require further analysis.
Evidence of a role for S. cerevisiae α‐arrestin Art1 (Ldb19) in mating projection and zygote formations
Authors: Choudhary Pooja , Loewen Michele C.
Published: August 2015

The discovery of arrestin‐mediated biased signalling mechanisms for mammalian G‐protein coupled receptors (GPCRs) has revolutionized the field over the last decade. Now, with the recent demonstration of a role for α‐arrestins in internalization of the yeast pheromone GPCR, Ste2p, the possibility of arrestin‐mediated alternate GPCR functionalities in yeast also follows. Here, the effects of knockout and complementation of yeast α‐arrestin expression during mating are reported. Although minor effects on classical pheromone‐related signalling are noted for a few arrestins, much stronger effects were observed downstream of cell cycle arrest, in particular linking Ldb19 (Art1) to mediation of zygote formation. Subsequent phenotypic observations linked this activity to more pronounced projection formation in an Art1 complemented noncuple α‐arrestin knockout line, compared to the knockout‐line alone, or either of the Art3 or Art6 complemented lines. Together with the observation of ligand‐stimulated localization of Art‐GFP to the mating projection, a possible role for this arrestin‐like protein in projection formation is supported. While leaving the full mechanism of alternate Art1 functionality to be elucidated, together these findings implicate Art1 in selective regulation of mating events downstream of receptor internalization and cell cycle arrest, leading to schmoo, and ultimately zygote formation.
The Power of Single‐Atom Catalysis
Authors: Liang Suxia , Hao Ce , Shi Yantao
Published: August 2015

Single‐atom catalysts (SACs) with individual and isolated metal atoms anchored to supports can act as active centers. Single‐atom catalysis is powerful and attractive because SACs have demonstrated distinguishing performances, such as drastic cost‐reduction, notable catalytic activity, and selectivity. Herein, we firstly introduce SAC, including the concept and some key issues in synthesis and catalysis. Then, the power of single‐atom catalysis is highlighted and the most recent advances are summarized. It is very encouraging that in recent years our understanding of SACs has increased, owing to substantial studies regarding sample preparation, characterization, evaluation, and also mechanistic interpretation. On the other hand, great challenges still remain for SACs.
Gd‐DTPA‐Dopamine‐Bisphytanyl Amphiphile: Synthesis, Characterisation and Relaxation Parameters of the Nanoassemblies and Their Potential as MRI Contrast Agents
Authors: Gupta Abhishek , Willis Scott A. , Waddington Lynne J. , Stait‐Gardner Tim , de Campo Liliana , Hwang Dennis W. , Kirby Nigel , Price William S. , Moghaddam Minoo J.
Published: August 2015

Here, a new amphiphilic magnetic resonance imaging (MRI) contrast agent, a GdIII‐chelated diethylenetriaminepentaacetic acid conjugated to two branched alkyl chains via a dopamine spacer, Gd‐DTPA‐dopamine‐bisphytanyl (Gd‐DTPA‐Dop‐Phy), which is readily capable of self‐assembling into liposomal nanoassemblies upon dispersion in an aqueous solution, is reported. In vitro relaxivities of the dispersions were found to be much higher than Magnevist, a commercially available contrast agent, at 0.47 T but comparable at 9.40 T. Analysis of variable temperature 17O NMR transverse relaxation measurements revealed the water exchange of the nanoassemblies to be faster than that previously reported for paramagnetic liposomes. Molecular reorientation dynamics were probed by 1H NMRD profiles using a classical inner and outer sphere relaxation model and a Lipari–Szabo “model‐free” approach. High payloads of GdIII ions in the liposomal nanoassemblies made solely from the Gd‐DTPA‐Dop‐Phy amphiphiles, in combination with slow molecular reorientation and fast water exchange makes this novel amphiphile a suitable candidate to be investigated as an advanced MRI contrast agent.
Mimicking Tyrosine Phosphorylation in Human Cytochrome c by the Evolved tRNA Synthetase Technique
Authors: Guerra‐Castellano Alejandra , Díaz‐Quintana Antonio , Moreno‐Beltrán Blas , López‐Prados Javier , Nieto Pedro M. , Meister Wiebke , Staffa Jana , Teixeira Miguel , Hildebrandt Peter , De la Rosa Miguel A. , Díaz‐Moreno Irene
Published: August 2015

Phosphorylation of tyrosine 48 of cytochrome c is related to a wide range of human diseases due to the pleiotropic role of the heme‐protein in cell life and death. However, the structural conformation and physicochemical properties of phosphorylated cytochrome c are difficult to study as its yield from cell extracts is very low and its kinase remains unknown. Herein, we report a high‐yielding synthesis of a close mimic of phosphorylated cytochrome c, developed by optimization of the synthesis of the non‐canonical amino acid p‐carboxymethyl‐L‐phenylalanine (pCMF) and its efficient site‐specific incorporation at position 48. It is noteworthy that the Y48pCMF mutation significantly destabilizes the FeMet bond in the ferric form of cytochrome c, thereby lowering the pKa value for the alkaline transition of the heme‐protein. This finding reveals the differential ability of the phosphomimic protein to drive certain events. This modified cytochrome c might be an important tool to investigate the role of the natural protein following phosphorylation.
Directing/Protecting‐Group‐Free Synthesis of Tetraaryl‐Substituted Pyrazoles through Four Direct Arylations on an Unsubstituted Pyrazole Scaffold
Authors: Fuse Shinichiro , Morita Taiki , Johmoto Kohei , Uekusa Hidehiro , Tanaka Hiroshi
Published: August 2015

A directing/protecting‐group‐free synthesis of 1,3,4,5‐tetraaryl‐substituted pyrazoles was achieved through four transition metal‐catalyzed direct arylations. Various pyrazoles with four different aryl rings were obtained using readily available reagents from an unsubstituted pyrazole. Two aryl‐substituted pyrazoles showed intense violet fluorescence, high quantum yields (Φf=0.68, 0.64), and large Stokes shifts (19000, 15200 cm−1).
Vicinal α,β‐Functionalizations of Amines: Cyclization Versus Dehydrogenative Hydrolysis
Authors: Jiang Fan , Achard Mathieu , Bruneau Christian
Published: August 2015

Direct vicinal α,β‐difunctionalization of tertiary cyclic amines is achieved in the presence of ruthenium or iridium transition‐metal complexes featuring phosphine‐sulfonate chelates. By varying the reaction conditions, α‐alkylated lactams were obtained by a formal dehydrogenative hydrolysis in which one molecule of hydrogen is generated from water.
INHIBIT‐Inspired Two‐Output DNA Logic Gates Based on Surface‐Enhanced Raman Scattering
Authors: Wu Zitong , Dong Boran , Zhou Xiaodong , Shen Aiguo , Hu Jiming
Published: August 2015

Herein, we presented a novel logic gate based on an INHIBITION gate that performs parallel readouts. Logic gates performing INHIBITION and YES/OR were constructed using surface‐enhanced Raman scattering as optical outputs for the first time. The strategy allowed for simultaneous reading of outputs in one tube. The applicability of this strategy has been successfully exemplified in the construction of half‐adder using the two‐output logic gates as reporting gates. This reporting strategy provides additional design flexibility for dynamic DNA devices.
Chiroptical Properties of Streptorubin B: The Synergy Between Theory and Experiment
Authors: Andrade Marta S. , Silva Vanessa S. , Lourenço Ana M. , Lobo Ana M. , Rzepa Henry S.
Published: August 2015

Analysis of the calculated and measured optical rotation (OR) together with other calculated chiroptical properties such as electronic circular dichroism (ECD) and vibrational circular dichroism (VCD) of the prodigiosin alkaloid streptorubin B shows that these are dominated by the pseudoenantiomeric atropisomers anti‐(S)‐streptorubin B (1A) and syn‐(S)‐streptorubin (1B). Atropisomerism is a dynamic phenomenon with a potentially nonequilibrium population of isomers, and accordingly the measured chiroptical responses may vary with time, concentration, temperature, and the anion of the salts used. Streptorubin also has the potential to form stacked homodimers for which the optical rotations measured at 589 nm can vary greatly due to the presence of ECD‐active electronic transitions in this region. Chirality 27:745–751, 2015. © 2015 Wiley Periodicals, Inc.
Synthese von aliphatischen Aldehyden aus Alkanen und Kohlendioxid: Valeraldehyd aus Butan und CO2 – Machbarkeit und Grenzen
Authors: Fritschi Susanne , Korth Wolfgang , Julis Jennifer , Kruse Daniela , Hahn Hanna , Franke Robert , Fleischer Ivana , Chowdhury Abhishek Dutta , Weding Nico , Jackstell Ralf , Beller Matthias , Jess Andreas
Published: August 2015

Bei der Optimierung chemischer Prozesse stehen die Steigerung der Energieeffizienz und die Einsparung von CO2‐Emissionen immer mehr im Fokus. Bei der Herstellung von Aldehyden könnte dies durch die Nutzung von Sonnenenergie zur fotokatalytischen Alkan‐Dehydrierung und der anschließenden Hydroformylierung mit CO2 erreicht werden. Mögliche Wege zur Identifikation geeigneter Katalysatorkonzepte für beide Reaktionsschritte, kinetische Untersuchungen zur fotokatalytischen Alkan‐Dehydrierung und die technische Machbarkeit der Hydroformylierung mit CO2 in einem kontinuierlichen Gasphasenprozess werden beschrieben. Zudem werden die für eine technische Anwendung zu lösenden Probleme diskutiert und beide Prozesse ökonomisch und ökologisch bewertet.
Dyes and Redox Couples with Matched Energy Levels: Elimination of the Dye‐Regeneration Energy Loss in Dye‐Sensitized Solar Cells
Authors: Jiang Dianlu , Darabedian Narek , Ghazarian Sevak , Hao Yuanqiang , Zhgamadze Maxim , Majaryan Natalie , Shen Rujuan , Zhou Feimeng
Published: August 2015

In dye‐sensitized solar cells (DSSCs), a significant dye‐regeneration force (ΔGreg0≥0.5 eV) is usually required for effective dye regeneration, which results in a major energy loss and limits the energy‐conversion efficiency of state‐of‐art DSSCs. We demonstrate that when dye molecules and redox couples that possess similar conjugated ligands are used, efficient dye regeneration occurs with zero or close‐to‐zero driving force. By using Ru(dcbpy)(bpy)22+ as the dye and Ru(bpy)2(MeIm)23+//2+ as the redox couple, a short‐circuit current (Jsc) of 4 mA cm−2 and an open‐circuit voltage (Voc) of 0.9 V were obtained with a ΔGreg0 of 0.07 eV. The same was observed for the N3 dye and Ru(bpy)2(SCN)21+/0 (ΔGreg0=0.0 eV), which produced an Jsc of 2.5 mA cm−2 and Voc of 0.6 V. Charge recombination occurs at pinholes, limiting the performance of the cells. This proof‐of‐concept study demonstrates that high Voc values can be attained by significantly curtailing the dye‐regeneration force.
A Highly Water‐Dispersible/Magnetically Separable Palladium Catalyst: Selective Transfer Hydrogenation or Direct Reductive N‐Formylation of Nitroarenes in Water
Authors: Karimi Babak , Mansouri Fariborz , Vali Hojatollah
Published: August 2015

Simple ion exchange of the chloride anion of an ionic‐liquid‐functionalized magnetic nanoparticle with [PdCl4]2− provided a highly water‐dispersible and magnetically separable palladium catalyst that exhibited excellent activity toward transfer hydrogenation reactions in water as a solvent. The catalyst demonstrated outstanding performance in aqueous‐phase transfer hydrogenation of various nitroarenes in a highly chemo‐ and regioselective manner by using HCOONH4 as a low‐cost, green, and easily available hydrogen donor. Also, by using only 0.25 mol % of the catalyst and formic acid as both a hydrogen donor and formylating agent, the catalyst showed excellent activity in the one‐pot, direct synthesis of N‐arylformamides from nitroarenes in water as a solvent. Notably, owing to the presence of a hydrophilic ionic liquid on the surface of silica‐coated iron oxide nanoparticles, the catalyst showed highly stable dispersion in water, as evidenced by the zeta potential and extremely low affinity to the organic phase. These features make this catalyst system suitable for an efficient double‐separation strategy (successive extraction/final magnetic separation). The recovered aqueous phase containing the catalyst can be simply and efficiently reused in eight runs without a decrease in activity and can be easily separated from the aqueous phase at the end of the process by applying an external magnetic field.
Isolation of Renewable Phenolics by Adsorption on Ultrastable Hydrophobic MIL‐140 Metal–Organic Frameworks
Authors: Van de Voorde Ben , Damasceno Borges Daiane , Vermoortele Frederik , Wouters Robin , Bozbiyik Belgin , Denayer Joeri , Taulelle Francis , Martineau Charlotte , Serre Christian , Maurin Guillaume , De Vos Dirk
Published: August 2015

The isolation and separation of phenolic compounds from aqueous backgrounds is challenging and will gain in importance as we become more dependent on phenolics from lignocellulose‐derived bio‐oil to meet our needs for aromatic compounds. Herein, we show that highly stable and hydrophobic Zr metal–organic frameworks of the MIL‐140 type are effective adsorbent materials for the separation of different phenolics and far outperform other classes of porous solids (silica, zeolites, carbons). The mechanism of the hydroquinone–catechol separation on MIL‐140C was studied in detail by combining experimental results with computational techniques. Although the differences in adsorption enthalpy between catechol and hydroquinone are negligible, the selective uptake of catechol in MIL‐140C is explained by its dense π–π stacking in the pores. The interplay of enthalpic and entropic effects allowed separation of a complex, five‐compound phenol mixture through breakthrough over a MIL‐140C column. Unlike many other metal–organic frameworks, MIL‐140C is remarkably stable and maintained structure, porosity and performance after five adsorption–desorption cycles.