bluuebunny/crossref_metadata_2025 huggingface dataset:
Ethical foundations and principles for collaborative research with Inuit and their governments
Authors: Felt Lawrence F. , Natcher David
Published: November 2012

Academic research in Canada involving Aboriginal peoples has changed dramatically during the last 20 years. From an academic researcher’s perspective, the changes have recently become formalised in the release of the 2nd edition of the Tri-Council Policy Statement on Ethics in Human Research. In this article we examine similarities and differences in the way ethical review is constructed and approached from university, Aboriginal and, in particular, Inuit perspectives. We begin our argument with a general comparison of research ethics as expressed in academic and Aboriginal sources in order to find areas of commonality, difference, and potential ambiguity between the two perspectives. We then briefly review our own experience with a multiyear research project involving several Inuit governments of different spatial and administrative scales. We conclude with discussion of a common issue arising from academic research, including our own work with Inuit and the research ethics board chaired by one of the authors. It concerns how to address potential tension between critical inquiry associated with Western scientific paradigms and respect and use of Inuit knowledge within a collaborative research process. In conclusion, we offer some “best practice advice” to academic researchers who face such a dilemma.
Malamuk – A (West) Frisian loanword in Greenlandic
Authors: Bakker Peter , van der Voort Hein
Published: November 2012

During the 17th and 18th centuries the Frisians and the Dutch were dominant in the whaling fisheries of the Davis Strait. They also traded with the Inuit and contributed to the Greenlandic pidgin that both parties used as a trade language. Despite intensive interethnic contacts, there are no traces of the Frisian or Dutch languages in modern Greenlandic, with the exception of the word malamuk ‘fulmar.’ In addition, similar forms are also attested in various Germanic languages. Although the exact etymological origin of this word and the precise route by which it ended up in Greenlandic have not been resolved completely, it is beyond doubt that Frisian and Dutch whaling crews were its point of entry.
Writing and publishing as empowerment in Baker Lake, Nunavut
Authors: Driedger Diane
Published: November 2012

This article examines creative writing, publishing, and empowerment of Inuit adult learners in Baker Lake, Nunavut. I taught a creative writing workshop at Nunavut Arctic College along with the local elders, who taught songs from the Baker Lake area. After the workshop, in February 2006 The Sound of Songs: Stories by Baker Lake Writers, an anthology of the adult learners’ writings, was published and launched at the Baker Lake Community Centre. In the course of the project, the Project Advisory Committee and I examined the meaning of the term “empowerment” in the context of Inuit culture. Each of the nine learners who took part in the workshop published at least one piece in the book. Most of them reported some degree of empowerment through increased confidence in their own writing, through increased respect from community members, especially the elders, and also through learning to be a “real Inuk” from the elders who taught songs from the Baker Lake area. Since most of the learners had not heard the songs before, elders and younger people had an opportunity to understand each other better.
The Breathing Tropical High‐Rise
Authors: Summ Wong Mun , Hassell Richard , Yeo Alina
Published: November 2012

In the last decade or so, the question of scale has been epitomised by the intense urbanisation of Southeast Asia with its burgeoning high‐rises. Wong Mun Summ, Richard Hassell and Alina Yeo of WOHA describe four projects that ameliorate high‐density living through design strategies that simultaneously harness innovative technological solutions and traditional knowledge to introduce comfort and green space into the living environment.
Developing a Sensitivity to Locale and ‘Human Experience’
Authors: Merkel Jayne
Published: November 2012

Most of the architects featured in this issue, who are known for their sensitivity to place, studied abroad and continue to practise and teach internationally. Jayne Merkel explores how a broadening of personal experience through travel has helped hone their affinity to the particular and the local over the standard and the global.
Tuning Dichroic Plasmon Resonance Modes of Gold Nanoparticles in Optical Thin Films
Authors: Gonzalez‐García Lola , Parra‐Barranco Julian , Sanchez‐Valencia Juan Ramón , Ferrer Javier , Garcia‐Gutierrez Mari‐Cruz , Barranco Angel , Gonzalez‐Elipe Agustín R.
Published: November 2012

A simple method is presented to tune the gold surface plasmon resonance (SPR) modes by growing anisotropic nanoparticles into transparent SiO2 thin films prepared by glancing angle deposition. In this type of composite film, the anisotropy of the gold nanoparticles, proved by gracing incidence small angle X‐ray scattering, is determined by the tilted nanocolumnar structure of the SiO2 host and yields a strong film dichroism evidenced by a change from an intense colored to a nearly transparent aspect depending on light polarization and/or sample orientation. The formation in these films of lithographic non‐dichroic SPR patterns by nanosecond laser writing demonstrates the potentialities of this procedure to develop novel optical encryption or anti‐counterfeiting structures either at micrometer‐ or macroscales.
Hierarchical Assembly of Complex Block Copolymer Nanoparticles into Multicompartment Superstructures through Tunable Interparticle Associations
Authors: Zhu Jiahua , Zhang Shiyi , Zhang Fuwu , Wooley Karen L. , Pochan Darrin J.
Published: November 2012

A challenging aim in both materials physics and chemistry is the construction of complex and functional superstructures from designed nanoscale building units. Block copolymer nanoparticles with morphological variety and compositional complexity have been made with solution‐based assembly. However, routine ability to build hierarchical superstructures by inter‐nanoparticle association is not yet possible. A hierarchical assembly strategy of organizing pre‐formed spherical block copolymer nanoparticles into superstructures, including linear, circular, and close‐packed arrays, via tunable interparticle interactions is presented. Solution‐state mixtures are made of two amphiphilic diblock copolymers, poly(acrylic acid)‐block‐poly(methyl methacrylate) (PAA‐b‐PMMA) and poly(acrylic acid)‐block‐polybutadiene (PAA‐b‐PB) with additional crown ether functionalities grafted onto 40 mol% of the AA repeat units on the PAA‐b‐PMMA diblock copolymer. Through kinetic control of the solution assembly process in aqueous/N,N‐dimethylformamide (DMF) mixtures (4:1 water:DMF), spherical nanoparticles with compositional complexity confined in both the core and shell are obtained. Benefiting from host‐guest chemistry, interparticle association is triggered and tuned by the addition of di‐functional organoamines due to amine‐crown ether complexation. The resultant multiparticle superstructures contain well‐defined multicompartments within individual, constituent nanoparticles due to the local separation of unlike PB and PMMA hydrophobic blocks within the cores of the individual particles. Through competitive complexation with potassium ions, the superstructures are disassembled into individual multicomparment nanoparticles.
Hypoxia and flow perfusion modulate proliferation and gene expression of articular chondrocytes on porous scaffolds
Authors: Dahlin Rebecca L. , Meretoja Ville V. , Ni Mengwei , Kasper F. Kurtis , Mikos Antonios G.
Published: November 2012

The combination of reduced oxygen tension and flow perfusion bioreactor culture is investigated for its effect on the proliferation, glycosaminoglycan production, and chondrogenic gene expression of bovine articular chondrocytes on porous polymer scaffolds. It was hypothesized that the combination of such factors would more closely replicate the in situ environment of these cells, leading to improvements in the cell phenotype. Chondrocytes were seeded onto electrospun poly(ε‐caprolactone) scaffolds and cultured in static or perfusion culture in either normoxic or hypoxic conditions for 6days. Results demonstrated that the combination of hypoxic and perfusion culture led to an increase in chondrocyte proliferation and glycosaminoglycan production, as well as an improvement in the ratio of collagen II/I gene expression over perfusion culture alone. The results demonstrate the need to combine multiple signals in vitro, in order to improve tissue growth by more closely replicating the native environment of cells. © 2013 American Institute of Chemical Engineers AIChE J, 59: 3158–3166, 2013
Termite fishing laterality in the fongoli savanna chimpanzees (Pan troglodytes verus): Further evidence of a left hand preference
Authors: Bogart S.L. , Pruetz J.D. , Ormiston L.K. , Russell J.L. , Meguerditchian A. , Hopkins W.D.
Published: November 2012

Whether nonhuman primates show population‐level handedness is a topic of much scientific debate. A previous study of handedness for termite fishing reported population‐level left handedness in the chimpanzees from Gombe National Park, Tanzania. In the current study, we examined whether similar hand preferences were evident in a savanna‐dwelling chimpanzee population with regards to termite fishing. Hand preference data were collected for 27 chimpanzees from February 2007 through July 2008 and November 2011 through January 2012 in southeastern Senegal. Overall, the Fongoli chimpanzees demonstrate a trend toward population‐level handedness, though the results did not reach conventional levels of statistical significance likely due to the limited sample size. Fongoli chimpanzees showed the same pattern of left hand preference as reported at Gombe and the two populations did not differ significantly. When the data were combined across all studies, wild chimpanzees showed a population‐level left hand preference for termite fishing. Am J Phys Anthropol, 2012. © 2012 Wiley Periodicals, Inc.
The aerodynamics of the sinonasal interface: the nose takes wing—a paradigm shift for our time
Authors: Gungor Anil A.
Published: November 2012

Background

Ventilation of and gas exchange between the nose and the paranasal sinuses are believed to occur by convection and diffusion based on experiments that neglect the effects of physiological respiration and aerodynamic forces at the sinonasal interface (SNI). Based on these experiments, the exchange of gas is presumed to be slow, and principally dependent on gas concentration and diameter, number, and location of ostia.

Methods

In 12 healthy adult volunteers, real‐time sinus nitric oxide measurements were obtained with catheters placed through natural ostia during respiratory maneuvers.

Results

The nose is a masterful collection of aerodynamic foils and channels designed to accomplish powered sinonasal gas exchange and ventilation within a few seconds during each inspiration.

Conclusion

The new perspective on the functional anatomy of the SNI demands a paradigm shift that is followed by physiological, medical, and surgical implications and a radical change in our perception and understanding.
Src and fibroblast growth factor 2 independently regulate signaling and gene expression induced by experimental injury to intact articular cartilage
Authors: Watt Fiona E. , Ismail Heba M. , Didangelos Athanasios , Peirce Matthew , Vincent Tonia L. , Wait Robin , Saklatvala Jeremy
Published: November 2012

Objective

To investigate whether cartilage injury activates protein tyrosine kinases distinct from fibroblast growth factor (FGF)–related signaling, and whether they contribute to injury‐induced gene responses.

Methods

Phosphokinases and protein tyrosine phosphorylation were assayed by Western blotting of cartilage lysates. Immunoprecipitation and Western blotting with 4G10 antibody and immunoprecipitation kinase assay were carried out. Tyrosine‐phosphorylated proteins on silver‐stained gels of injured cartilage lysates were identified by mass spectrometry. Messenger RNA induction in cartilage explants was assessed by quantitative reverse transcriptase–polymerase chain reaction.

Results

Protein tyrosine phosphorylation occurred within seconds of injury to the surface of intact articular cartilage, as did activation of MAPKs and IKK. Activation did not reoccur upon reinjury of cultured explants. The prominent tyrosine‐phosphorylated proteins focal adhesion kinase, paxillin, and cortactin were identified as substrates of Src family kinases. The Src family kinase inhibitor PP2 blocked injury‐induced tyrosine phosphorylation. It did not prevent activation of the MAPKs and IKK but differentially inhibited 8 of 10 inflammatory response genes that were induced by injury. In contrast, FGF signaling blockade with PD173074 reduced all MAPK and IKK activation by ∼50% and inhibited a different subset of genes but had no effect on Src‐like signaling.

Conclusion

Injury to the surface of intact articular cartilage activates Src‐like kinases as well as MAPKs and IKK (implying NF‐κB activation). FGF‐2 contributes to MAPK/IKK activation but not to Src‐like signaling, suggesting that the latter is a parallel pathway that also regulates the injury‐induced inflammatory gene response.
Alpha2‐antiplasmin regulates the development of dermal fibrosis in mice by prostaglandin F2α synthesis through adipose triglyceride lipase/calcium‐independent phospholipase A2
Authors: Kanno Yosuke , Kawashita Eri , Kokado Akiko , Okada Kiyotaka , Ueshima Shigeru , Matsuo Osamu , Matsuno Hiroyuki
Published: November 2012

Objective

Systemic sclerosis (SSc) is characterized by fibrosis of the skin and visceral organs. Patients with SSc have enhanced plasma levels of the plasmin–α2‐antiplasmin (α2AP) complex, and we recently implicated α2AP in the development of fibrosis through transforming growth factor β (TGFβ) production. This study was undertaken to clarify how α2AP induces TGFβ production and the development of fibrosis.

Methods

To clarify the detailed mechanism by which α2AP induces TGFβ production, we focused on adipose triglyceride lipase (ATGL)/calcium‐independent phospholipase A2 (iPLA2) and examined whether ATGL/ iPLA2 is associated with α2AP‐induced TGFβ production. The mouse model of bleomycin‐induced SSc was used to evaluate the role of α2AP in the development of fibrosis. Dermal thickness and collagen content were determined in mouse skin treated with phosphate buffered saline or bleomycin. Moreover, we cultured SSc‐like fibroblasts from the bleomycin‐treated mouse skin and examined the production of TGFβ and prostaglandin F2α (PGF2α).

Results

We found that α2AP binding to ATGL promoted PGF2α synthesis through iPLA2 in fibroblasts, and the PGF2α synthesis that was promoted by α2AP induced TGFβ production in fibroblasts. In addition, the neutralization of α2AP attenuated the production of TGFβ and PGF2α in SSc‐like fibroblasts from mice. The α2AP deficiency attenuated bleomycin‐induced fibrosis and PGF2α synthesis, while the administration of PGF2α to α2AP‐deficient mice facilitated α2AP deficiency–attenuated fibrosis.

Conclusion

These findings suggest that α2AP regulates the development of fibrosis by PGF2α synthesis through ATGL/iPLA2. The inhibition of α2AP‐initiated pathways might provide a novel therapeutic approach to fibrotic diseases.
Clinical and transcriptional response to the long‐acting interleukin‐1 blocker canakinumab in Blau syndrome–related uveitis
Authors: Simonini Gabriele , Xu Zhaohui , Caputo Roberto , De Libero Cinzia , Pagnini Ilaria , Pascual Virginia , Cimaz Rolando
Published: November 2012

Objective

To report on the clinical response to canakinumab in a patient with sporadic nucleotide‐binding oligomerization domain–containing protein 2 (NOD‐2)–associated pediatric granulomatous arthritis (Blau syndrome) and severe resistant panuveitis, and to describe gene expression profile changes throughout such treatment.

Methods

A 4‐year‐old boy was diagnosed as having Blau syndrome on the basis of typical clinical features, histologic evidence of noncaseating granulomas, and a NOD2 mutation. Ocular involvement was initially controlled by topical and oral corticosteroids, but over the years visual impairment and complications, such as macular edema and retinal detachment, progressed. Ocular disease remained persistently active despite treatment with multiple different immunosuppressants; therefore, canakinumab treatment was started. Before and during the first 6 months of treatment, the gene expression profile was determined each month.

Results

Canakinumab treatment was well tolerated and led to rapid quiescence of uveitis, which had been continuously active before this treatment. Gene expression profiling analysis of the patient's blood prior to initiation of interleukin‐1 (IL‐1) blockade revealed differential expression of 1,993 transcripts when compared to healthy controls, and among the up‐regulated transcripts, pathway analysis showed that the predominant network consisted of innate immunity–related transcripts. The transcriptional signature of the patient overlapped with the transcriptional signature of patients with systemic‐onset juvenile idiopathic arthritis, and canakinumab treatment led to the normalization of most of these transcriptional changes.

Conclusion

The pathogenesis of Blau syndrome may be mediated by IL‐1, and canakinumab may be useful when this disorder is unresponsive to more conventional treatments.
Großversuche zur Ermüdung von Litzenseilen auf Umlenksätteln für Schrägseilbrücken
Authors: Schlaich Mike , Abdalsamad Ayham , Annan Rachid
Published: November 2012

Schrägseil‐ oder Extradosed‐Brücken sind dadurch gekennzeichnet, dass in der Regel die Seile, die den Überbau tragen, alle im Pylon enden und dort einzeln verankert sind. Um die Verankerung zu vereinfachen und um Platz zu sparen, werden neuerdings auch Sattelsysteme eingesetzt, die wie bei Hängebrücken, die Seile – heute meist Litzenbündel – am Pylonkopf ohne Zwischenverankerung von einer Seite zur anderen durchführen. Während das Trag‐ und Ermüdungsverhalten einzelner Litzen unter Axialbelastung ausgiebig erforscht ist, gibt es für zug‐ und biegebeanspruchte Litzen mit Sattelsystemen mit kleinen Radien noch wenig Erfahrung.

Die Einrichtungen am Institut für Bauingenieurwesen der Technischen Universität Berlin boten die Möglichkeit, Ermüdungsversuche für Litzen‐Sattelsysteme mit 55 und 37 Litzen durchzuführen. Diese Versuche wurden in den Jahren 2009 und 2010 in Übereinstimmung mit den fib‐Empfehlungen, Bulletin 30, vom Januar 2005 durchgeführt.

In diesem Bericht werden kurz die heute verwendeten Sattelsysteme für Litzenbündel von Schrägseilbrücken und die Prüfmethoden für Ermüdungsversuche an Litzenseilen oder ‐bündeln beschrieben. Ausführlich wird auf die Anlage und die Versuche an der TU Berlin sowie die seither durchgeführte Forschung eingegangen.

Large scale fatigue tests of strands on saddle systems for cable‐stayed bridges

Stay cables made of parallel strands for cable‐stayed or extradosed bridges are usually anchored in the pylon or the mast of the bridge. New saddle systems provide the opportunity to support them by saddles that guide the strands continuously from one side of the pylon to the other. While cables made of strands have been tested for fatigue extensively, saddle systems were not yet tested much although the fatigue mechanism occurring inside a saddle is particularly complex. The need to perform such a test and the facilities that exist at the Berlin Institute of Technology (TU Berlin), Department of Civil and Structural Engineering provided the unique opportunity to perform large scale fatigue test on cable saddle systems with 55 and with 37 strands. These tests were performed in accordance to fib recommendations, bulletin 30, January 2005. This paper describes the saddle systems used today as well as the test rig and tests conducted in Berlin.
Statistical multi‐path exposure method for assessing the whole‐body SAR in a heterogeneous human body model in a realistic environment
Authors: Vermeeren Günter , Joseph Wout , Martens Luc
Published: November 2012

Assessing the whole‐body absorption in a human in a realistic environment requires a statistical approach covering all possible exposure situations. This article describes the development of a statistical multi‐path exposure method for heterogeneous realistic human body models. The method is applied for the 6‐year‐old Virtual Family boy (VFB) exposed to the GSM downlink at 950 MHz. It is shown that the whole‐body SAR does not differ significantly over the different environments at an operating frequency of 950 MHz. Furthermore, the whole‐body SAR in the VFB for multi‐path exposure exceeds the whole‐body SAR for worst‐case single‐incident plane wave exposure by 3.6%. Moreover, the ICNIRP reference levels are not conservative with the basic restrictions in 0.3% of the exposure samples for the VFB at the GSM downlink of 950 MHz. The homogeneous spheroid with the dielectric properties of the head suggested by the IEC underestimates the absorption compared to realistic human body models. Moreover, the variation in the whole‐body SAR for realistic human body models is larger than for homogeneous spheroid models. This is mainly due to the heterogeneity of the tissues and the irregular shape of the realistic human body model compared to homogeneous spheroid human body models. Bioelectromagnetics 34:240–251, 2013. © 2012 Wiley Periodicals, Inc.
Infraleichtbeton 2.0
Authors: Schlaich Mike , Hückler Alex
Published: November 2012

Infraleichtbeton, sehr leichter Beton als tragende Wärmedämmung, verspricht dauerhafte, nachhaltige und ansprechende Sichtbetonbauten. Ein im Jahr 2007 gebautes Haus aus diesem Hochleistungsleichtbeton hat sich bewährt und wurde in dieser Zeitschrift bereits vorgestellt. Der Infraleichtbeton ist nun so weiterentwickelt worden, dass er bei gleichen Wärmedämmeigenschaften doppelt so fest ist. Die dazu betriebene Forschung an der Technischen Universität Berlin und der Bau einer Probewand aus Infraleichtbeton 2.0 für den Entwurf eines Pavillons, der den Innovationspreis der Holcim Foundation gewonnen hat, sollen hier vorgestellt werden.

Infra‐Lightweight Concrete 2.0

Infra‐Lightweight Concrete acts as load‐bearing heat insulation and promises durable, sustainable and attractive fair‐faced concrete structures. A building made of this high performance lightweight aggregate concrete in 2007 was presented in this journal. Since then, while maintaining the heat insulating properties, the compressive strength has been doubled. This paper presents both the associated research and further development at the Technische Universität in Berlin as well as a wall mock‐up for a pavilion which was awarded with an innovation price by the Holcim Foundation.
Current strategies in antibody engineering: Fc engineering and pH‐dependent antigen binding, bispecific antibodies and antibody drug conjugates
Authors: Vincent Karen J. , Zurini Mauro
Published: November 2012

Antibody engineering technologies are constantly advancing to improve the clinical effectiveness of monoclonal antibodies (mAbs). Effector functions may be modified by engineering the Fc region, for example to improve or reduce binding to Fc gamma receptors (FcγRs) or complement factors. Other examples for Fc engineering include modification of the half‐life of immunoglobulin G (IgG); various studies have shown that half‐life can be prolonged by increasing the affinity of Fc for the Fc neonatal receptor (FcRn). Furthermore, engineered pH‐dependent antigen binding can be applied to enhance the recycling of IgG via FcRn, enabling binding to additional target molecules. Since bispecific approaches may elicit desired effects on disease targets, a variety of bispecific formats have been developed, including variants that structurally mimic IgG. Finally, antibody‐drug conjugates (ADCs) create new opportunities for treatment of certain diseases. Advances in antibody generation, selection of highly cytotoxic molecules and production of stable linkers have paved the way to the development of many ADCs that can be tested in clinical trials. This review covers current antibody engineering strategies for the modification of therapeutic antibodies in the areas of Fc engineering and pH‐dependent antigen binding, bispecific antibodies and ADCs.
Targeted nitric oxide delivery preferentially induces glioma cell chemosensitivity via altered p53 and O6‐Methylguanine‐DNA Methyltransferase activity
Authors: Safdar Shahana , Payne Courtney A. , Tu Nam H. , Taite Lakeshia J.
Published: November 2012

Glioblastoma multiforme is the most common malignant central nervous system tumor, and also among the most difficult to treat due to a lack of response to chemotherapeutics. New methods of countering the mechanisms that confer chemoresistance to malignant gliomas could lead to significant advances in the quest to identify novel drug combinations or targeted drug delivery systems for cancer therapy. In this study, we investigate the use of a targeted nitric oxide (NO) donor as a pretreatment to sensitize glioma cells to chemotherapy. The protein chlorotoxin (CTX) has been shown to preferentially target glioma cells, and we have developed CTX–NO, a glioma‐specific, NO‐donating CTX derivative. Pretreatment of cells with CTX–NO followed by 48‐h exposure to either carmustine (BCNU) or temozolomide (TMZ), both common chemotherapeutics used in glioma treatment, resulted in increased efficacy of both therapeutics. After CTX–NO exposure, both T98G and U‐87MG human malignant glioma cells show increased sensitivity to BCNU and TMZ. Further investigation revealed that the consequences of this combination therapy was a reduction in active levels of the cytoprotective enzyme MGMT and altered p53 activity, both of which are essential in DNA repair and tumor cell resistance to chemotherapy. The combination of CTX–NO and chemotherapeutics also led to decreased cell invasion. These studies indicate that this targeted NO donor could be an invaluable tool in the development of novel approaches to treat cancer. Biotechnol. Bioeng. 2013; 110: 1211–1220. © 2012 Wiley Periodicals, Inc.
Light‐responsive current generation by phototrophically enriched anode biofilms dominated by green sulfur bacteria
Authors: Badalamenti Jonathan P. , Torres César I. , Krajmalnik‐Brown Rosa
Published: November 2012

The objective of this study was to employ microbial electrochemical cells (MXCs) to selectively enrich and examine anoxygenic photosynthetic bacteria for potential anaerobic respiration capabilities using electrodes. In the process, we designed a novel enrichment strategy that manipulated the poised anode potential, light, nitrogen availability, and media supply to promote growth of phototrophic bacteria while minimizing co‐enrichment of non‐phototrophic anode‐respiring bacteria (ARB). This approach resulted in light‐responsive electricity generation from fresh‐ and saltwater inocula. Under anoxic conditions, current showed a negative light response, suggesting that the enriched phototrophic consortia shifted between phototrophic and anaerobic respiratory metabolism. Molecular, physical, and electrochemical analyses elucidated that anode biofilms were dominated by green sulfur bacteria, and biofilms exhibited anode respiration kinetics indicative of non‐mediated electron transfer, but kinetic parameters differed from values previously reported for non‐phototrophic ARB. These results invite the utilization of MXCs as microbiological tools for exploring anaerobic respiratory capabilities among anoxygenic photosynthetic bacteria. Biotechnol. Bioeng. 2013; 110: 1020–1027. © 2012 Wiley Periodicals, Inc.
Cryopreservation of pluripotent stem cell aggregates in defined protein‐free formulation
Authors: Sart Sébastien , Ma Teng , Li Yan
Published: November 2012

Cultivation of undifferentiated pluripotent stem cells (PSCs) as aggregates has emerged as an efficient culture configuration, enabling rapid and controlled large scale expansion. Aggregate‐based PSC cryopreservation facilitates the integrated process of cell expansion and cryopreservation, but its feasibility has not been demonstrated. The goals of current study are to assess the suitability of cryopreserving intact mouse embryonic stem cell (mESC) aggregates and investigate the effects of aggregate size and the formulation of cryopreservation solution on mESC survival and recovery. The results demonstrated the size‐dependent cell survival and recovery of intact aggregates. In particular, the generation of reactive oxygen species (ROS) and caspase activation were reduced for small aggregates (109 ± 55 μm) compared to medium (245 ± 77 μm) and large (365 ± 141 μm) ones, leading to the improved cell recovery. In addition, a defined protein‐free formulation was tested and found to promote the aggregate survival, eliminating the cell exposure to animal serum. The cryopreserved aggregates also maintained the pluripotent markers and the differentiation capacity into three‐germ layers after thawing. In summary, the cryopreservation of small PSC aggregates in a defined protein‐free formulation was shown to be a suitable approach toward a fully integrated expansion and cryopreservation process at large scale. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2013
Production and scale‐up of a monoclonal antibody against 17‐hydroxyprogesterone
Authors: Chua Gek Kee , Abdul‐Rahman Badarulhisam , Chisti Yusuf
Published: November 2012

The hybridoma 192 was used to produce a monoclonal antibody (MAb) against 17‐hydroxyprogesterone (17‐OHP), for possible use in screening for congenital adrenal hyperplasia (CAH). The factors influencing the MAb production were screened and optimized in a 2 L stirred bioreactor. The production was then scaled up to a 20 L bioreactor. All of the screened factors (aeration rate, stirring speed, dissolved oxygen concentration, pH, and temperature) were found to significantly affect production. Optimization using the response surface methodology identified the following optimal production conditions: 36.8°C, pH 7.4, stirring speed of 100 rpm, 30% dissolved oxygen concentration, and an aeration rate of 0.09 vvm. Under these conditions, the maximum viable cell density achieved was 1.34 ± 0.21 × 106cells mL−1and the specific growth rate was 0.036 ± 0.004 h−1. The maximum MAb titer was 11.94 ± 4.81 μg mL−1with an average specific MAb production rate of 0.273 ± 0.135 pg cell−1h−1. A constant impeller tip speed criterion was used for the scale‐up. The specific growth rate (0.040 h−1) and the maximum viable cell density (1.89 × 106cells mL−1) at the larger scale were better than the values achieved at the small scale, but the MAb titer in the 20 L bioreactor was 18% lower than in the smaller bioreactor. A change in the culture environment from the static conditions of a T‐flask to the stirred bioreactor culture did not affect the specificity of the MAb toward its antigen (17‐OHP) and did not compromise the structural integrity of the MAb. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2013
Comparative analysis of heterologous expression, biochemical characterization optimal production of an alkaline α‐amylase from alkaliphilic Alkalimonas amylolytica in Escherichia coli and Pichia pastoris
Authors: Yang Haiquan , Liu Long , Shin Hyun‐dong , Chen Rachel R. , Li Jianghua , Du Guocheng , Chen Jian
Published: November 2012

An alkaline α‐amylase gene from alkaliphilic Alkalimonas amylolytica was synthesized based on the preferred codon usage of Escherichia coli and Pichia pastoris, respectively, and then was expressed in the according heterologous host, E. coli BL21 (DE3) and P. pastoris GS115. The alkaline α‐amylase expressed in E. coli was designated AmyA, whereas that produced by P. pastoris was designated AmyB. The specific activity of AmyA and AmyB was 16.0 and 16.6 U/mg at pH 9.5 and 50°C, respectively. The optimal pH and pH stability of AmyA and AmyB were similar, whereas the optimum temperature and thermal stability of AmyB were slightly enhanced compared with those of AmyA. The AmyA and AmyB had a similar melting temperature of 64°C and the same catalytic efficiency (kcat/Km) of 2.0 × 106 L/(mol min). AmyA and AmyB were slightly activated by 1 mM Co2+, Ca2+, or Na+, but inhibited by all other metal ions (K+, Mg2+, Fe3+, Fe2+, Zn2+, Mn2+, and Cu2+). Tween 80 or Tween 60 (10% (w/v)) had little influence on the stability of AmyA and AmyB, while the 10% (w/v) sodium dodecyl sulfate caused the complete loss of AmyA and AmyB activities. The AmyA and AmyB were stable in the presence of solid detergents (washing powder), while were less stable in liquid detergents. Under the optimal conditions in 3‐L bioreactor, the extracellular AmyB activity reached 600 U/mL, which was about 10 times as that of AmyA. These results indicated that P. pastoris was a preferable host for alkaline α‐amylase expression and the produced alkaline α‐amylase had a certain application potential in solid detergents. © 2012 American Institute of Chemical Engineers Biotechnol. Prog., 2013
Increasing the Productivity of Peroxidase‐Catalyzed Oxyfunctionalization: A Case Study on the Potential of Two‐Liquid‐Phase Systems
Authors: Churakova Ekaterina , Arends Isabel W. C. E. , Hollmann Frank
Published: November 2012

Biocatalysis, which occurs mostly in aqueous reaction media, is generally incompatible with the hydrophobic nature of many reactants. This may be overcome by using the two‐liquid‐phase system (2 LPS) approach. We demonstrate the beneficial application of the 2 LPS approach for the photobiocatalytic oxyfunctionalization of thioanisole. Compared to aqueous reaction conditions, the 2 LPS approach not only allowed for higher substrate loadings (without the use of additional solvents) but also increased the productivity and robustness of the overall reaction.
Palladium‐Catalyzed Ethylene/Methyl Acrylate Cooligomerization: Effect of a New Nonsymmetric α‐Diimine
Authors: Meduri Angelo , Montini Tiziano , Ragaini Fabio , Fornasiero Paolo , Zangrando Ennio , Milani Barbara
Published: November 2012

A new nonsymmetric bis(aryl‐imino)acenaphthene (Ar‐BIAN) ligand, featured by a subtle steric and electronic unbalance of the N‐donor atoms, is reported. With the new ligand and the corresponding symmetrically substituted derivatives, both neutral and monocationic PdCH3 compounds have been synthesized and characterized. The series of the monocationic complexes [Pd(CH3)(L)(Ar‐BIAN)][PF6] (L=CH3CN, dmso) has been extended to dimethyl sulfoxide derivatives. The monocationic complexes are tested as precatalysts for the ethylene/methyl acrylate cooligomerization under mild reaction conditions of temperature and ethylene pressure. The catalytic product is a mixture of ethylene/acrylate cooligomers and higher alkenes. The catalysts containing the new nonsymmetric ligand are found to be more productive than those with the symmetric Ar‐BIANs. The Pd–dmso catalysts are more productive and show a longer lifetime than their Pd–NCCH3 counterparts.
Modeling and Simulation of Industrial PVC Drying in Fluidized Beds with Internal Heat Source
Authors: Rodrigues Tacidelli A. , Tavernard Pereira Neto A. , Pereira Brito R. , Brandão de Araujo A. C. , Gonzaga Sales Vasconcelos L. , Nicácio Alves J. J.
Published: November 2012

An engineering application case study on a two‐fluid flow model for the control of industrial drying operations is reported. The mathematical model of this process was numerically solved by a computer code developed in FORTRAN language and was validated through data taken from PVC drying performed in an industrial continuous fluidized‐bed dryer. The predicted steady‐state outlet temperature and PVC moisture content values agree with the real data observed on the industrial plant. This model was also used to predict the temperature and concentration profiles inside the dryer as a function of time as a response to the disturbances and variations on the PVC water content at the dryer inlet.
Kinetics of o‐Xylene Combustion over a Pt/Alumina Catalyst
Authors: Manta C. M. , Bozga G. , Bercaru G. , Bîldea C. S.
Published: November 2012

o‐Xylene combustion in air over a Pt/γ‐Al2O3 catalyst was investigated in a laboratory reactor at low concentrations typical for depollution applications. The results evidenced a slightly negative influence of o‐xylene concentration on combustion rate. A kinetic model of the combustion process was developed by using the Langmuir‐Hinshelwood mechanism, assuming the surface reaction between adsorbed oxygen atoms and adsorbed o‐xylene molecules as controlling step. The rate expression includes the influences of o‐xylene and water adsorption on the active centers of the catalyst. The estimation of rate expression parameters is based on o‐xylene conversion measurements obtained under conditions free of influences of physical steps.
A New Signal‐On Photoelectrochemical Biosensor Based on a Graphene/Quantum‐Dot Nanocomposite Amplified by the Dual‐Quenched Effect of Bipyridinium Relay and AuNPs
Authors: Zhang Xiaoru , Xu Yunpeng , Yang Yanqiang , Jin Xia , Ye Sujuan , Zhang Shusheng , Jiang Lilin
Published: November 2012

A new photoelectrochemical (PEC) biosensor was developed by using carboxyl‐functionalized graphene and CdSe nanoparticles. This sensitive interface was then successfully applied to detection of thrombin based on the dual‐quenched effect of PEC nanoparticle, which relied on the electron transfer of a bipyridinium relay and energy transfer of AuNPs. After recognition with an aptamer, the PEC nanoparticle was removed and a signal‐on PEC biosensor was obtained. Moreover, the bio‐barcode technique used in the preparation of PEC nanoparticle could avoid cross‐reaction and enhances the sensitivity. Taking advantages of the various methods mentioned above, the sensitivity could be easily enhanced. In addition, in this work we also investigated graphene that was modified with different functional groups and AuNPs of different particle sizes. Under optimal conditions, a detection limit of 5.9×10−15 M was achieved. With its simplicity, selectivity, and sensitivity, this strategy shows great promise for the fabrication of highly efficient PEC biosensors.
Kinetic Properties of a Novel Fusarium solani (phospho)lipase: A Monolayer Study
Authors: Jallouli Raida , Fendri Ahmed , Mechichi Tahar , Gargouri Youssef Talèl , Bezzine Sofiane
Published: November 2012

Using the monomolecular film technique, we studied interfacial properties of Fusarium solani lipase (FSL). This lipolytic enzyme was found to be unique among the fungal lipases possessing not only a lipase activity but also a high phospholipase one.The FSL was able to hydrolyze dicaprin films at various surface pressures. The surface pressure dependency, the stereospecificity, and the regioselectivity of FSL were performed using optically pure stereoisomers of diglyceride (1,2‐sn‐ dicaprin and 2,3‐sn‐dicaprin) and a prochiral isomer (1,3‐sn‐dicaprin) spread as monomolecular films at the air–water interface. The FSL prefers adjacent ester groups of the diglyceride isomers (1,2‐sn‐dicaprin and 2,3‐sn‐dicaprin) at low and high surface pressures. Furthermore, FSL was found to be markedly stereospecific for the sn‐1 position of the 1,2‐sn‐enantiomer of dicaprin at both low and high surface pressures.Moreover, FSL shows high activities on phospholipids monolayers. However, this enzyme displays high preference to zwitterionic phospholipids compared to the negatively charged ones. Chirality, 25:35‐38, 2012. © 2012 Wiley Periodicals, Inc.
Common mechanisms regulating cell cortex properties during cell division and cell migration
Authors: Roubinet Chantal , Tran Phong T. , Piel Matthieu
Published: November 2012

Single cell morphogenesis results from a balance of forces involving internal pressure (also called turgor pressure in plants and fungi) and the plastic and dynamic outer shell of the cell. Dominated by the cell wall in plants and fungi, mechanical properties of the outer shell of animal cells arise from the cell cortex, which is mostly composed of the plasma membrane (and membrane proteins) and the underlying meshwork of actin filaments and myosin motors (and associated proteins). In this review, following Bray and White [1988; Science 239:883–889], we draw a parallel between the regulation of the cell cortex during cell division and cell migration in animal cells. Starting from the similarities in shape changes and underlying mechanical properties, we further propose that the analogy between cell division and cell migration might run deeper, down to the basic molecular mechanisms driving cell cortex remodeling. We focus our attention on how an heterogeneous and dynamic cortex can be generated to allow cell shape changes while preserving cell integrity. © 2012 Wiley Periodicals, Inc.
Anatomical and electrophysiological mechanisms for asymmetrical excitatory propagation in the rat insular cortex: In vivo optical imaging and whole‐cell patch‐clamp studies
Authors: Adachi Kazunori , Fujita Satoshi , Yoshida Atsushi , Sakagami Hiroshi , Koshikawa Noriaki , Kobayashi Masayuki
Published: November 2012

The insular cortex (IC) integrates limbic information from the amygdala and hypothalamic nucleus to multimodal sensory inputs, including visceral, gustatory, and somatosensory information. However, the functional framework of excitation in the IC is still unknown. We performed optical imaging and single pyramidal neuronal staining using a whole‐cell patch‐clamp technique in urethane‐anesthetized rats to elucidate the precise anatomical and physiological features of IC pyramidal neurons, which regulate cortical information processing via their horizontal connections. Optical imaging revealed that electrical stimulation of the granular (GI) or dysgranular (DI) IC elicited characteristic excitatory propagations along the rostrocaudal axis parallel to the rhinal fissure, with a preference toward the rostral direction. Spatial patterns of the dendrites and axons of layer II/III pyramidal cells in the DI/GI support these functional features of excitation; for example, rostrocaudal axonal arbors tend to extend with a rostral directional preference. The mean length of the axons from the soma to the farthest site rostrally was ∼50% longer than that of the caudal length. Pyramidal cells in the DI/GI exhibited spontaneous membrane oscillation in the UP and DOWN states. Similarly to the evoked signals obtained by optical imaging, repetitive electrical stimulation of the caudal IC ∼1 mm away from the recorded cells (five pulses at 50 Hz) induced the summation of evoked excitatory postsynaptic potentials during the DOWN state and profound inhibitory postsynaptic potentials during the UP state. Clarification of the excitation feature with its cellular basis provides new clues about the functional mechanisms of the asymmetric propagation of neural activities in the IC. J. Comp. Neurol. 521:1598–1613, 2013. © 2012 Wiley Periodicals, Inc.
Activity and coexpression of Drosophila black with ebony in fly optic lobes reveals putative cooperative tasks in vision that evade electroretinographic detection
Authors: Ziegler Anna B. , Brüsselbach Florian , Hovemann Bernhard T.
Published: November 2012

Drosophila mutants black and ebony show pigmentation defects in the adult cuticle, which disclose their cooperative activity in β‐alanyl‐dopamine formation. In visual signal transduction, Ebony conjugates β‐alanine to histamine, forming β‐alanyl‐histamine or carcinine. Mutation of ebony disrupts signal transduction and reveals an electroretinogram (ERG) phenotype. In contrast to the corresponding cuticle phenotype of black and ebony, there is no ERG phenotype observed when black expression is disrupted. This discrepancy calls into question the longstanding assumption of Black and Ebony interaction. The purpose of this study was to investigate the role of Black and Ebony in fly optic lobes. We excluded a presynaptic histamine uptake pathway and confirmed histamine recycling via carcinine formation in glia. β‐Alanine supply for this pathway is independent of enzymatic synthesis by Black and β‐alanine synthase Pyd3. Two versions of Black are expressed in vivo. Black is a specific aspartate decarboxylase with no activity on glutamate. RNA in situ hybridization and anti‐Black antisera localized Black expression in the head. Immunolabeling revealed expression in lamina glia, in large medulla glia, in glia of the ocellar ganglion, and in astrocyte‐like glia below the ocellar ganglion. In these glia types, Black expression is strictly accompanied by Ebony expression. Activity, localization, and strict coexpression with Ebony strongly indicate a specific mode of functional interaction that, however, evades ERG detection. J. Comp. Neurol., 521:1207–1224, 2013. © 2012 Wiley Periodicals, Inc.
Specializations of intercellular junctions are associated with the presence and absence of hair cell regeneration in ears from six vertebrate classes
Authors: Burns Joseph C. , Collado Maria Sol , Oliver Eric R. , Corwin Jeffrey T.
Published: November 2012

Sensory hair cell losses lead to hearing and balance deficits that are permanent for mammals, but temporary for nonmammals because supporting cells in their ears give rise to replacement hair cells. In mice and humans, vestibular supporting cells grow exceptionally large circumferential F‐actin belts and their junctions express E‐cadherin in patterns that strongly correlate with postnatal declines in regeneration capacity. In contrast, chicken supporting cells retain thin F‐actin belts throughout life and express little E‐cadherin. To determine whether the junctions in chicken ears might be representative of other ears that also regenerate hair cells, we investigated inner ears from dogfish sharks, zebrafish, bullfrogs,Xenopus, turtles, and the lizard,Anolis. As in chickens, the supporting cells in adult zebrafish,Xenopus, and turtle ears retained thin circumferential F‐actin belts and expressed little E‐cadherin. Supporting cells in adult sharks and bullfrogs also retained thin belts, but were not tested for E‐cadherin. Supporting cells in adultAnolisexhibited wide, but porous webs of F‐actin and strong E‐cadherin expression.Anolissupporting cells also showed some cell cycle reentry when cultured. The results reveal that the association between thin F‐actin belts and low E‐cadherin is shared by supporting cells in anamniotes, turtles, and birds, which all can regenerate hair cells. Divergent junctional specializations in supporting cells appear to have arisen independently inAnolisand mammals. The presence of webs of F‐actin at the junctions inAnolisappears compatible with supporting cell proliferation, but the solid reinforcement of the F‐actin belts in mammals is associated with its absence. J. Comp. Neurol., 521:1430–1448, 2013. © 2012 Wiley Periodicals, Inc.