bluuebunny/crossref_metadata_2025 huggingface dataset:
A universal benchmark?
Authors: Bell A. G. , Hallowell P. J. , Long D. H.
Published: October 2011

The present trend towards mediocrity in computer science is partly due to the discouragement of one of the most fertile activities in the subject; namely game playing.

This paper presents results, derived by a chess program, which can have useful applications.
MUSYS: Software for an electronic music studio
Authors: Grogono Peter
Published: October 2011

MUSYS is a system of programs used to create electronic music at the computer studio of Electronic Music Studios, London. This paper describes the programming language employed by composers, and the implementation of its compiler and of other programs in the system. It is shown that by the use of a macrogenerator, an efficient and useful system can be built from simple software on a small computer.
APET—A versatile tool for estimating computer application performance
Authors: Baird R.
Published: October 2011

This article describes a technique for controlling computer system activity in order to measure selected hardware or software functions, as they interact within an application under real operating conditions. APET is an approach for manufacturing synthetic benchmark or yardstick programs that exercise the computer system.
Mehrdimensional energieoptimierte Gebäudehüllen in Stahlleichtbauweise für den Industrie‐ und Gewerbebau
Authors: Feldmann Markus , Kuhnhenne Markus , Brieden Matthias , Rexroth Susanne , Deininger Florian , Hachul Helmut , Bach Janine , Rößling Heike , Ummenhofer Thomas , Misiek Thomas , Krüger Helmut
Published: October 2011

Bislang standen vorwiegend Geschoss‐ und Wohnbauten im Fokus der Nachhaltigkeitsbetrachtung im Hochbau. Der Industrie‐ und Gewerbebau als wichtiger Bereich des Stahlbausektors indes ist damit noch unberücksichtigt. Um jedoch das Prinzip der Nachhaltigkeit auch auf den Industrie‐ und Gewerbebau zu übertragen, ist die Erforschung der Ressourcen‐ und Energieverbräuche von Gebäuden in Stahlleichtbauweise wichtig. In diesem Kontext ist es Ziel des Forschungsprojekts P 880, die Verbesserungspotentiale bestehender Fassadenelemente zu untersuchen und neue Entwicklungskorridore auf diesem Gebiet zu erschließen. Der vorliegende Beitrag soll für die besonderen Herausforderungen, aber auch Entwicklungsmöglichkeiten von Gebäudehüllen in Stahlleichtbauweise sensibilisieren. Es werden die angestrebten Ziele benannt, mögliche Lösungsansätze umrissen und die daraus resultierenden Forschungsarbeiten aufgezeigt, die in dem kürzlich begonnen Projekt P 880 bearbeitet werden.

Multidimensional energy‐optimized building envelopes in steel lightweight construction for industrial and commercial buildings. So far, mainly multi‐storey and residential buildings were in the focus of sustainability analysis in structural engineering. The industrial and commercial construction as an important area of the steel sector is still ignored. However, in order to apply the principle of sustainability in the industrial and commercial construction, the exploration of resources and energy consumption of buildings in lightweight steel construction is important. In this context, the aim of the research project P 880 is to investigate the potential for improvement of existing facade elements and to open up new development corridors in this area. The following article aims to raise awareness of the specific challenges but also opportunities for development of building envelopes in steel lightweight construction. The targeted objectives are named, possible solutions are outlined and the hence resulting researches are identified, which are processed in the recently started project P 880.
Bauen im Bestand – Potenziale und Chancen der Stahl‐/Stahlleichtbauweise
Authors: Floerke Paul , Weiß Sonja , Ungermann Dieter , Schütz Alena , Gralla Mike , Brandt Tim , Ummenhofer Thomas , Zinke Tim , Herrmann Christoph , Dettmer Tina , Tichelmann Karsten , Ziegler Bastian
Published: October 2011

Die nachhaltige Nutzung der Kernstädte und ihrer vorhandenen Gebäudestrukturen wird derzeit vorangetrieben und politisch unterstützt. Studien belegen, dass die Schwerpunkte des Bauens der nächsten Jahrzehnte im Bestand liegen. Mit dem prognostizierten, wachsenden Markt des Bauens im Bestand – der Verdichtung, Modernisierung und Sanierung von bestehenden Gebäuden – ergeben sich große Chancen für den Stahl‐/Stahlleichtbau.

Die großen Vorteile des Stahls können jedoch nur ausgenutzt werden, wenn Architekten und Ingenieuren umfassende Planungshilfen und Bewertungskriterien zur Verfügung gestellt werden, die den interdisziplinären Bauaufgaben im Bestand unter ganzheitlicher Berücksichtigung von stadtplanerischen und architektonischen sowie bauphysikalischen Aspekten, statisch‐konstruktiven Anforderungen, Aspekten des Baubetriebs und der Immobilienbewertung sowie einer Nachhaltigkeitsbewertung (Life‐Cycle‐Design) gerecht werden. Dieses Ziel soll mit diesem interdisziplinären Forschungsvorhaben unterstützt werden, wozu der vorliegende Beitrag einen ersten Einblick gibt.

Zur Weiterentwicklung notwendiger, von einem Industrie‐ und Wissenschaftskreis als substanziell eingestufter Innovationen in der Stahlanwendung wurde das Forschungscluster NASTA ins Leben gerufen. In diesen Kontext gehört auch das aktuelle Forschungsprojekt [1].

Existing buildings – Potentials of lightweight design of steel structures. The sustainable utilization of urban areas and existing buildings is currently becoming extremely important. Studies prove that aspects such as the refurbishment and restoration of existing buildings will be the challenge of future. Urban concentration, modernization and redevelopment will lead to a growing market and will initiate manifold fields of application for steel and lightweight steel structures. The enormous advantages of steel can only be utilized if a wide fundamental knowledge basis, planning tools, and criteria for a sustainability assessment are provided for architects and engineers. These planning instruments must meet interdisciplinary and holistic requirements as well as city planning and architectural demands.

Aspects of building physics, structural solutions, building process concerns, real estate assessment and sustainability assessment within the life cycle shall be addressed in this interdisciplinary research project. The project presented in this paper is part of a research cluster and a first insight in the objectives and methodology used will be provided here. Supervised by an industrial and scientific committee, the NASTA research cluster was established to support essential innovations and to improve steel applications [1].
Communicating with patients in the 21st century
Authors: Collins Justin , Backhouse Dudley
Published: October 2011

Recent improvements in technology have had a major impact on how we communicate with patients and deliver health information and care. The authors outline the ways in which telemedicine can lead to healthcare cost savings while improving patient care. Copyright © 2011 Wiley Interface Ltd
Management of nocturia
Authors: Khan Faisal Rauf , Younis Ayman , Alosta Ahmed , Khan Shahid A.A.
Published: October 2011

The main causes of nocturia, or voiding at night, are reduced bladder capacity and nocturnal polyuria. The authors discuss lifestyle changes that may help address this bothersome symptom, and outline the available treatment choices. Copyright © 2011 Wiley Interface Ltd
Functional analysis of variant lysosomal acid glycosidases of Anderson‐Fabry and Pompe disease in a human embryonic kidney epithelial cell line (HEK 293 T)
Authors: Ebrahim Hatim Y. , Baker Robert J. , Mehta Atul B. , Hughes Derralynn A.
Published: October 2011

The functional significance of missense mutations in genes encoding acid glycosidases of lysosomal storage disorders (LSDs) is not always clear. Here we describe a method of investigating functional properties of variant enzymes in vitro using a human embryonic kidney epithelial cell line. Site‐directed mutagenesis was performed on the parental plasmids containing cDNA encoding for alpha‐galactosidase A (α‐Gal A) and acid maltase (α‐Glu) to prepare plasmids encoding relevant point mutations. Mutant plasmids were transfected into HEK 293 T cells, and transient over‐expression of variant enzymes was measured after 3 days. We have illustrated the method by examining enzymatic activities of four unknown α‐Gal A and one α‐Glu variants identified in our patients with Anderson‐Fabry disease and Pompe diseases respectively. Comparison with control variants known to be either pathogenic or non‐pathogenic together with over‐expression of wild‐type enzyme allowed determination of the pathogenicity of the mutation. One leader sequence novel variant of α‐Gal A (p.A15T) was shown not to significantly reduce enzyme activity, whereas three other novel α‐Gal A variants (p.D93Y, p.L372P and p.T410I) were shown to be pathogenic as they resulted in significant reduction of enzyme activity. A novel α‐Glu variant (p.L72R) was shown to be pathogenic as this significantly reduced enzyme activity. Certain acid glycosidase variants that have been described in association with late‐onset LSDs and which are known to have variable residual plasma and leukocyte enzyme activity in patients appear to show intermediate to low enzyme activity (p.N215S and p.Q279E α‐Gal A respectively) in the over‐expression system.
Comparative Study of Effect of Surfactant‐Polymer Interactions on Properties of Alkyl Polyglucosides and Alpha Olefin Sulphonate
Authors: Momin Shamin A. , Yeole Pradnya
Published: October 2011

The properties of Alpha Olefin Sulphonate (AOS) and Alkyl polyglucosides (APG) were studied in the presence and absence of nonionic polymers such as polyethylene glycol, poly vinyl pyrrolidone and methyl cellulose and hydroxy propyl cellulose. Properties like surface tension, foaming, viscosity and emulsification were studied at a constant concentration of polymer (0.1%) and varying concentrations of surfactant. It was found that at low surfactant concentrations there is an association between surfactant and polymer at the liquid/air surface in the case of an anionic surfactant and a nonionic polymer, which is not seen in the case of nonionic surfactants and nonionic polymers. A nonionic polymer reduces the surface tension of AOS by forming a surfactant‐polymer complex which in turn increases the foamability, emulsifying property and viscosity of solution. APG does not show any effect on its surface tension in the presence of nonionic polymers but its foamability and emulsifying properties are improved. Reduction in surface tension is not the only reason behind increased foamability in the presence of the polymer. Higher molecular weight polymers give a rich, creamy foam because of increased viscosity in the surfactant solution as compared to lower molecular weight polymers.
ON THE DEGREE DISTANCE OF SOME COMPOSITE GRAPHS
Authors: HUA HONGBO
Published: October 2011

Let G be a connected simple graph. The degree distance of G is defined as D′(G)=∑ u∈V (G)dG(u)DG(u), where DG(u) is the sum of distances between the vertex u and all other vertices in G and dG(u) denotes the degree of vertex u in G. In contrast to many established results on extremal properties of degree distance, few results in the literature deal with the degree distance of composite graphs. Towards closing this gap, we study the degree distance of some composite graphs here. We present explicit formulas for D′ (G) of three composite graphs, namely, double graphs, extended double covers and edge copied graphs.
ON TENSOR PRODUCTS OF WEAK MIXING VECTOR SEQUENCES AND THEIR APPLICATIONS TO UNIQUELY E-WEAK MIXING C*-DYNAMICAL SYSTEMS
Authors: MUKHAMEDOV FARRUKH
Published: October 2011

We prove that, under certain conditions, uniform weak mixing (to zero) of the bounded sequences in Banach space implies uniform weak mixing of their tensor product. Moreover, we prove that ergodicity of tensor product of the sequences in Banach space implies their weak mixing. As applications of the results obtained, we prove that the tensor product of uniquely E-weak mixing C*-dynamical systems is also uniquely E-weak mixing.
Family Firms in Hyderabad: Gujarati, Goswami, and Marwari Patterns of Adoption, Marriage, and Inheritance
Authors: Leonard Karen Isaksen
Published: October 2011

Scholars are looking again at banking and mercantile families in India's early modern history, responding to the challenge issued by Claude Markovits in the epilogue of his 2008 volume,Merchants, Traders, Entrepreneurs, to “return the merchant to South Asian history.” Some of the underlying assumptions and questions being asked are old and some are new. My own longstanding assumption, upon which this article relies, has been that bankers and merchants played multiple and important roles with respect to states in South Asia, and that their relations with non-kin officials and other political actors determined their success or failure and sometimes the success or failure of a state, most notably, the Mughal state. Questions are again being raised about “trust,” assumed to be a leading attribute of and asset to financial networks (especially in long-distance trade diasporas), and the notion so commonly put forward by scholars to explain the success of Hindu banking and mercantile communities. Recent work by Francesca Trivellato has found that membership in the Sephardic trade diaspora facilitated but did not guarantee trust or cooperation: the Sephardic merchants relied on non-Jewish as well as Jewish agents and networks of information, and evolving legal norms guided their business activities.
Ethics, Politics, and Host Space: A Comparative Case Study from the South American Chaco
Authors: Lowrey Kathleen
Published: October 2011

This essay compares two communities of common origin that now dwell in separate rural lowland South American settings, one in the Bolivian Chaco and the other in the Paraguayan Chaco (maps 1 and 2). South America's Gran Chaco is sparsely populated, averaging one person per three square kilometers (Censo Nacional Indígena [Paraguay], 2002). Nevertheless, the present essay takes as its analytic-theoretical point of departure a phrase invoked by Michael Warner in his 1999 book on queer publics in New York City: “Urban space is always a host space” (1999: 190).
Waste and Potency: Making Men with Minerals in Guanajuato and Tucson
Authors: Ferry Elizabeth Emma
Published: October 2011

In the mines of Guanajuato, Mexico, when miners drill and dynamite for metallic ore, they dislodge other substances. Among these are elements and compounds known as “minerals,” sold and collected in their own right as scientific specimens or aesthetic collectibles. These minerals often fetch thousands of dollars at mineral shows and collector showrooms in Tucson, Arizona and other mineral collecting hubs. In this process, minerals move from byproducts and even waste to highly valued commodities in their own right.
Knowledge in health technology assessment: Who, what, how?
Authors: Tjørnhøj-Thomsen Tine , Hansen Helle Ploug
Published: October 2011

Health systems are placing more and more emphasis on designing and delivering services that are focused on the patient, and there is a growing interest in patient aspects of health policy research and health technology assessment (HTA). Only a few HTA agencies use and invest in scientific methods to generate knowledge and evidence about the patient aspects of a given technology. This raises questions about how knowledge is produced in HTA reports and what kind of knowledge is considered relevant. This article uses a Danish HTA on patient education from 2009 as empirical material for a critical examination and discussion of knowledge and knowledge production about the patient aspects of HTA.
Public Opinion, Organized Labor, and the Limits of New Deal Liberalism, 1936–1945
Authors: Schickler Eric , Caughey Devin
Published: October 2011

The seemingly wide opening for liberal domestic policy innovation by the U.S. federal government in the early-to-mid-1930s gave way to a much more limited agenda in the late 1930s and 1940s. The latter years saw the consolidation and gradual extension of several key programs (e.g., Social Security and Keynesian macroeconomic management), but also the frustration of liberal hopes for an expansive “cradle-to-grave” welfare state marked by strong national unions, national health insurance, and full employment policies. Drawing upon rarely used early public opinion polls, we explore the dynamics of public opinion regarding New Deal liberalism during this pivotal era. We argue that a broadly based reaction against labor unions created a difficult backdrop for liberal programmatic advances. We find that this anti-labor reaction was especially virulent in the South but divided even Northern Democrats, thus creating an effective wedge issue for Republicans and their Southern conservative allies. More generally, we find that the mass public favored most of the specific programs created by the New Deal, but was hardly clamoring for major expansions of the national government's role in the late 1930s and 1940s. These findings illuminate the role played by the South in constraining New Deal liberalism while also highlighting the tenuousness of the liberal majority in the North.
Testing claims of a usage-based phonology with Liverpool Englisht-to-r
Authors: CLARK LYNN , WATSON KEVIN
Published: October 2011

The variable phenomenon in which /t/ can be realized as a tap or rhotic approximant in varieties of Northern British English (commonly referred to ast-to-r, Wells 1982: 370) has received some attention in English linguistics as debates have appeared over how best to model its phonology (e.g. Carr 1991; Dochertyet al. 1997; Broadbent 2008). The occurrence oft-to-rseems to be constrained by the preceding and following phonological environment in a largely systematic way and so it is often accounted for within a rule-based model of grammar. Problematically, however, the rule does not apply blindly across the board to all words which fit the specified phonological pattern. Instead,t-to-rshows evidence of being lexically restricted, and this fact has recently encouraged a usage-based interpretation. Until now, there has been relatively little attempt to test the usage-based thesis directly with fully quantified data gleaned from naturally occurring conversation. This article investigates the extent to which certain usage-based predictions can account for variation attested int-to-rin Liverpool English. Using oral history interviews with Liverpool English speakers born in the early 1900s, we examine the usage-based predictions first proposed by Broadbent (2008) thatt-to-ris more likely in (a) high-frequency words and (b) high-frequency phrases. There is some support for the importance of lexical frequency as a motivating factor in the use oft-to-r, but our data do not fully support either of these claims wholesale. We suggest thatt-to-ris not constrained simply by word frequency or phrase frequency alone, but by a combination of both. Finally, we explore the possibility of employing notions from Cognitive Grammar such as schema strength (e.g. Taylor 2002; Bybee 1995: 430) in our interpretation of these data.
Interferon-gamma- and perforin-mediated immune responses for resistance againstToxoplasma gondiiin the brain
Authors: Suzuki Yasuhiro , Sa Qila , Gehman Marie , Ochiai Eri
Published: October 2011

Toxoplasma gondiiis an obligate intracellular protozoan parasite that causes various diseases, including lymphadenitis, congenital infection of fetuses and life-threatening toxoplasmic encephalitis in immunocompromised individuals. Interferon-gamma (IFN-γ)-mediated immune responses are essential for controlling tachyzoite proliferation during both acute acquired infection and reactivation of infection in the brain. Both CD4+and CD8+T cells produce this cytokine in response to infection, although the latter has more potent protective activity. IFN-γcan activate microglia, astrocytes and macrophages, and these activated cells control the proliferation of tachyzoites using different molecules, depending on cell type and host species. IFN-γalso has a crucial role in the recruitment of T cells into the brain after infection by inducing expression of the adhesion molecule VCAM-1 on cerebrovascular endothelial cells, and chemokines such as CXCL9, CXCL10 and CCL5. A recent study showed that CD8+T cells are able to removeT. gondiicysts, which represent the stage of the parasite in chronic infection, from the brain through their perforin-mediated activity. Thus, the resistance to cerebral infection withT. gondiirequires a coordinated network using both IFN-γ- and perforin-mediated immune responses. Elucidating how these two protective mechanisms function and collaborate in the brain againstT. gondiiwill be crucial in developing a new method to prevent and eradicate this parasitic infection.
TGF‐β1 re‐programs TLR4 signaling in L. donovani infection: enhancement of SHP‐1 and ubiquitin‐editing enzyme A20
Authors: Das Sushmita , Pandey Krishna , Kumar Ashish , Sardar Abul H , Purkait Bidyut , Kumar Manish , Kumar Sudeep , Ravidas Vidya N , Roy Syamal , Singh Dharmendra , Das Pradeep
Published: October 2011

Visceral leishmaniasis (VL), caused by Leishmania donovani, is a major health concern in India. It represents T‐helper type 2 (Th2) bias of cytokines in active state and Th1 bias at cure. However, the role of the parasite in regulating Toll‐like receptor (TLR)‐mediated macrophage activation in VL patients remains elusive. In this report, we demonstrated that later stages of L. donovani infection rendered tolerance to macrophages, leading to incapability for the production of inflammatory cytokines like tumor necrosis factor (TNF)‐α and interleukin (IL)‐1β in response to TLR stimulation. Overexpression of transforming growth factor (TGF)‐β1, but not IL‐10, resulted in suppressed lipopolysaccharide (LPS)‐induced production of TNF‐α and downregulation of TLR4 expression in L. donovani‐infected macrophages. Recombinant human (rh)TGF‐β1 markedly enhanced tyrosine phosphatase (Src homology region 2 domain‐containing phosphatase‐1) activity, but inhibited IL‐1 receptor‐activated kinase (IRAK)‐1 activation. Addition of neutralizing TGF‐β1 antibody reversed these effects, and thus suggesting the pivotal role of TGF‐β1 in promoting refractoriness for LPS in macrophages. Surprisingly, the use of a tyrosine phosphatase inhibitor (sodium orthovanadate, Na3VO4) promoted IRAK‐1 activation, confirming the negative inhibitory role of tyrosine phosphatase in macrophage activation. Furthermore, rhTGF‐β1 induced tolerance in infected macrophages by reducing inhibitory protein (IκBα) degradation in a time‐dependent manner. In addition, short interfering RNA studies proved that overexpression of A20 ubiquitin‐editing protein complex induced inhibitory activity of TGF‐β1 on LPS‐mediated nuclear factor‐κB activation. Thus, these findings suggest that TGF‐β1 promotes overexpression of A20 through tyrosine phosphatase activity that ensures transient activation of inflammatory signaling pathways in macrophages in active L. donovani infection.
The SOX compliance journey at Trinity Industries
Authors: Schultze Ulrike
Published: October 2011

Process and information technology changes in organizations are not always voluntary and motivated by strategic goals. Instead, they may be imposed on organizations by regulatory bodies and certifying agencies. This teaching case focuses on one company's multi-year journey of making process and information technology changes so as to comply with a new set of regulations known as the Sarbanes-Oxley Act (SOX). Even though SOX compliance work focuses on designing, implementing, and testing internal controls, these controls are nothing but activities designed to ensure that processes implicated in the production of financial information are completed correctly and that the financial representations they generate are reliable. Thus, despite its emphasis on internal controls, accounting and auditing, this teaching case provides students with insights into compliance-related process improvement and system integration in general.
Combining meteorites and missions to explore Mars
Authors: McCoy Timothy J. , Corrigan Catherine M. , Herd Christopher D. K.
Published: October 2011

Laboratory studies of meteorites and robotic exploration of Mars reveal scant atmosphere, no evidence of plate tectonics, past evidence for abundant water, and a protracted igneous evolution. Despite indirect hints, direct evidence of a martian origin came with the discovery of trapped atmospheric gases in one meteorite. Since then, the study of martian meteorites and findings from missions have been linked. Although the meteorite source locations are unknown, impact ejection modeling and spectral mapping of Mars suggest derivation from small craters in terrains of Amazonian to Hesperian age. Whereas most martian meteorites are young (< 1.3 Ga), the spread of whole rock isotopic compositions results from crystallization of a magma ocean > 4.5 Ga and formation of enriched and depleted reservoirs. However, the history inferred from martian meteorites conflicts with results from recent Mars missions, calling into doubt whether the igneous histor y inferred from the meteorites is applicable to Mars as a whole. Allan Hills 84001 dates to 4.09 Ga and contains fluid-deposited carbonates. Accompanying debate about the mechanism and temperature of origin of the carbonates came several features suggestive of past microbial life in the carbonates. Although highly disputed, the suggestion spurred interest in habitable extreme environments on Earth and throughout the Solar System. A flotilla of subsequent spacecraft has redefined Mars from a volcanic planet to a hydrologically active planet that may have harbored life. Understanding the history and habitability of Mars depends on understanding the coupling of the atmosphere, surface, and subsurface. Sample return that brings back direct evidence from these diverse reservoirs is essential.
Mitogen-activated protein kinase kinase kinase 1 (MAP3K1) integrates developmental signals for eyelid closure
Authors: Geh Esmond , Meng Qinghang , Mongan Maureen , Wang Jingcai , Takatori Atsushi , Zheng Yi , Puga Alvaro , Lang Richard A. , Xia Ying
Published: October 2011

Developmental eyelid closure is an evolutionarily conserved morphogenetic event requiring proliferation, differentiation, cytoskeleton reorganization, and migration of epithelial cells at the tip of the developing eyelid. Many signaling events take place during eyelid closure, but how the signals converge to regulate the morphogenetic process remains an open and intriguing question. Here we show that mitogen-activated protein kinase kinase kinase 1 (MAP3K1) highly expressed in the developing eyelid epithelium, forms with c-Jun, a regulatory axis that orchestrates morphogenesis by integrating two different networks of eyelid closure signals. A TGF-α/EGFR-RhoA module initiates one of these networks by inducing c-Jun expression which, in a phosphorylation-independent manner, binds to the
Map3k1
promoter and causes an increase in MAP3K1 expression. RhoA knockout in the ocular surface epithelium disturbs this network by decreasing MAP3K1 expression, and causes delayed eyelid closure in
Map3k1
hemizygotes. The second network is initiated by the enzymatic activity of MAP3K1, which phosphorylates and activates a JNK-c-Jun module, leading to AP-1 transactivation and induction of its downstream genes, such as
Pai-1
. MAP3K1 inactivation reduces AP-1 activity and PAI-1 expression both in cells and developing eyelids. MAP3K1 is therefore the nexus of an intracrine regulatory loop connecting the TGF-α/EGFR/RhoA-c-Jun and JNK-c-Jun-AP-1 pathways in developmental eyelid closure.
Astrocytes carrying the superoxide dismutase 1 (SOD1
G93A
) mutation induce wild-type motor neuron degeneration in vivo
Authors: Papadeas Sophia T. , Kraig Sarah E. , O'Banion Colin , Lepore Angelo C. , Maragakis Nicholas J.
Published: October 2011

Recent studies highlight astrocytes as key drivers of motor neuron (MN) degeneration and disease propagation in mutant human superoxide dismutase 1 (mSOD1)-mediated amyotrophic lateral sclerosis. However, in vivo analysis of specific astrocytic influence in amyotrophic lateral sclerosis has proven difficult because mSOD1 is ubiquitously expressed throughout the CNS of rodent models studied. Here, we transplanted SOD1
G93A
glial-restricted precursor cells—glial progenitors capable of differentiating into astrocytes—into the cervical spinal cord of WT rats to reveal how mutant astrocytes influence WT MNs and other cells types (microglia and astrocytes) in an in vivo setting. Transplanted SOD1
G93A
glial-restricted precursor cells survived and differentiated efficiently into astrocytes. Graft-derived SOD1
G93A
astrocytes induced host MN ubiquitination and death, forelimb motor and respiratory dysfunction, reactive astrocytosis, and reduced GLT-1 transporter expression in WT animals. The SOD1
G93A
astrocyte-induced MN death seemed in part mediated by host microglial activation. These findings show that mSOD1 astrocytes alone can induce WT MN death and associated pathological changes in vivo.
Ultrahigh resolution protein structures using NMR chemical shift tensors
Authors: Wylie Benjamin J. , Sperling Lindsay J. , Nieuwkoop Andrew J. , Franks W. Trent , Oldfield Eric , Rienstra Chad M.
Published: October 2011

NMR chemical shift tensors (CSTs) in proteins, as well as their orientations, represent an important new restraint class for protein structure refinement and determination. Here, we present the first determination of both CST magnitudes and orientations for
13
C
α
and
15
N (peptide backbone) groups in a protein, the β1 IgG binding domain of protein G from
Streptococcus
spp., GB1. Site-specific
13
C
α
and
15
N CSTs were measured using synchronously evolved recoupling experiments in which
13
C and
15
N tensors were projected onto the
1
H-
13
C and
1
H-
15
N vectors, respectively, and onto the
15
N-
13
C vector in the case of
13
C
α
. The orientations of the
13
C
α
CSTs to the
1
H-
13
C and
13
C-
15
N vectors agreed well with the results of ab initio calculations, with an rmsd of approximately 8°. In addition, the measured
15
N tensors exhibited larger reduced anisotropies in α-helical versus β-sheet regions, with very limited variation (18 ± 4°) in the orientation of the
z
-axis of the
15
N CST with respect to the
1
H-
15
N vector. Incorporation of the
13
C
α
CST restraints into structure calculations, in combination with isotropic chemical shifts, transferred echo double resonance
13
C-
15
N distances and vector angle restraints, improved the backbone rmsd to 0.16 Å (PDB ID code 2LGI) and is consistent with existing X-ray structures (0.51 Å agreement with PDB ID code 2QMT). These results demonstrate that chemical shift tensors have considerable utility in protein structure refinement, with the best structures comparable to 1.0-Å crystal structures, based upon empirical metrics such as Ramachandran geometries and
χ
1
/
χ
2
distributions, providing solid-state NMR with a powerful tool for de novo structure determination.
Elevated Hedgehog/Gli signaling causes β-cell dedifferentiation in mice
Authors: Landsman Limor , Parent Audrey , Hebrok Matthias
Published: October 2011

Although Hedgehog (Hh) signaling regulates cell differentiation during pancreas organogenesis, the consequences of pathway up-regulation in adult β-cells in vivo have not been investigated. Here, we elevate Hh signaling in β-cells by expressing an active version of the GLI2 transcription factor, a mediator of the Hh pathway, in β-cells that are also devoid of primary cilia, a critical regulator of Hh activity. We show that increased Hh signaling leads to impaired β-cell function and insulin secretion, resulting in glucose intolerance in transgenic mice. This phenotype was accompanied by reduced expression of both genes critical for β-cell function and transcription factors associated with their mature phenotype. Increased Hh signaling further correlated with increased expression of the precursor cell markers Hes1 and Sox9, both direct Hh targets that are normally excluded from β-cells. Over time, the majority of β-cells down-regulated GLI2 levels, thereby regaining the full differentiation state and restoring normoglycemia in transgenic mice. However, sustained high Hh levels in some insulin-producing cells further eroded the β-cell identity and eventually led to the development of undifferentiated pancreatic tumors. Summarily, our results indicate that deregulation of the Hh pathway impairs β-cell function by interfering with the mature β-cell differentiation state.
Lipocalin-2 controls neuronal excitability and anxiety by regulating dendritic spine formation and maturation
Authors: Mucha Mariusz , Skrzypiec Anna E. , Schiavon Emanuele , Attwood Benjamin K. , Kucerova Eva , Pawlak Robert
Published: October 2011

Psychological stress causes adaptive changes in the nervous system directed toward maintaining homoeostasis. These biochemical and structural mechanisms regulate animal behavior, and their malfunction may result in various forms of affective disorders. Here we found that the
lipocalin-2
(
Lcn2
) gene, encoding a secreted protein of unknown neuronal function, was up-regulated in mouse hippocampus following psychological stress. Addition of lipocalin-2 to cultured hippocampal neurons reduced dendritic spine actin's mobility, caused retraction of mushroom spines, and inhibited spine maturation. These effects were further enhanced by inactivating iron-binding residues of Lcn-2, suggesting that they were facilitated by the iron-free form of Lcn-2. Concurrently, disruption of the
Lcn2
gene in mice promoted stress-induced increase in spine density and caused an increase in the proportion of mushroom spines. The above changes correlated with higher excitability of CA1 principal neurons and with elevated stress-induced anxiety in Lcn-2
−/−
mice. Our study demonstrates that lipocalin-2 promotes stress-induced changes in spine morphology and function to regulate neuronal excitability and anxiety.
Chronic inflammation promotes myeloid-derived suppressor cell activation blocking antitumor immunity in transgenic mouse melanoma model
Authors: Meyer Christiane , Sevko Alexandra , Ramacher Marcel , Bazhin Alexandr V. , Falk Christine S. , Osen Wolfram , Borrello Ivan , Kato Masashi , Schadendorf Dirk , Baniyash Michal , Umansky Viktor
Published: October 2011

Tumor microenvironment is characterized by chronic inflammation represented by infiltrating leukocytes and soluble mediators, which lead to a local and systemic immunosuppression associated with cancer progression. Here, we used the
ret
transgenic spontaneous murine melanoma model that mimics human melanoma. Skin tumors and metastatic lymph nodes showed increased levels of inflammatory factors such as IL-1β, GM-CSF, and IFN-γ, which correlated with tumor progression. Moreover, Gr1
+
CD11b
+
myeloid-derived suppressor cells (MDSCs), known to inhibit tumor reactive T cells, were enriched in melanoma lesions and lymphatic organs during tumor progression. MDSC infiltration was associated with a strong TCR ζ-chain down-regulation in all T cells. Coculturing normal splenocytes with tumor-derived MDSC induced a decreased T-cell proliferation and ζ-chain expression, verifying the MDSC immunosuppressive function and suggesting that the tumor inflammatory microenvironment supports MDSC recruitment and immunosuppressive activity. Indeed, upon manipulation of the melanoma microenvironment with the phosphodiesterase-5 inhibitor sildenafil, we observed reduced levels of numerous inflammatory mediators (e.g., IL-1β, IL-6, VEGF, S100A9) in association with decreased MDSC amounts and immunosuppressive function, indicating an antiinflammatory effect of sildenafil. This led to a partial restoration of ζ-chain expression in T cells and to a significantly increased survival of tumor-bearing mice. CD8 T-cell depletion resulted in an abrogation of sildenafil beneficial outcome, suggesting the involvement of MDSC and CD8 T cells in the observed therapeutic effects. Our data imply that inhibition of chronic inflammation in the tumor microenvironment should be applied in conjunction with melanoma immunotherapies to increase their efficacy.
Structure determination of an intercalating ruthenium dipyridophenazine complex which kinks DNA by semiintercalation of a tetraazaphenanthrene ligand
Authors: Hall James P. , O’Sullivan Kyra , Naseer Abeer , Smith Jayden A. , Kelly John M. , Cardin Christine J.
Published: October 2011

We describe a crystal structure, at atomic resolution (1.1 Å, 100 K), of a ruthenium polypyridyl complex bound to duplex DNA, in which one ligand acts as a wedge in the minor groove, resulting in the 51° kinking of the double helix. The complex cation Λ-[Ru(1,4,5,8-tetraazaphenanthrene)
2
(dipyridophenazine)]
2+
crystallizes in a 1∶1 ratio with the oligonucleotide d(TCGGCGCCGA) in the presence of barium ions. Each complex binds to one duplex by intercalation of the dipyridophenazine ligand and also by semiintercalation of one of the orthogonal tetraazaphenanthrene ligands into a second symmetrically equivalent duplex. The result is noncovalent cross-linking and marked kinking of DNA.
Natural gas and temperature structured a microbial community response to the
Deepwater Horizon
oil spill
Authors: Redmond Molly C. , Valentine David L.
Published: October 2011

Microbial communities present in the Gulf of Mexico rapidly responded to the
Deepwater Horizon
oil spill. In deep water plumes, these communities were initially dominated by members of
Oceanospirillales, Colwellia,
and
Cycloclasticus
. None of these groups were abundant in surface oil slick samples, and
Colwellia
was much more abundant in oil-degrading enrichment cultures incubated at 4 °C than at room temperature, suggesting that the colder temperatures at plume depth favored the development of these communities. These groups decreased in abundance after the well was capped in July, but the addition of hydrocarbons in laboratory incubations of deep waters from the Gulf of Mexico stimulated
Colwellia's
growth.
Colwellia
was the primary organism that incorporated
13
C from ethane and propane in stable isotope probing experiments, and given its abundance in environmental samples at the time that ethane and propane oxidation rates were high, it is likely that
Colwellia
was active in ethane and propane oxidation in situ.
Colwellia
also incorporated
13
C benzene, and
Colwellia
's abundance in crude oil enrichments without natural gas suggests that it has the ability to consume a wide range of hydrocarbon compounds or their degradation products. However, the fact that ethane and propane alone were capable of stimulating the growth of
Colwellia
, and to a lesser extent,
Oceanospirillales
, suggests that high natural gas content of this spill may have provided an advantage to these organisms.
A complex between contactin-1 and the protein tyrosine phosphatase PTPRZ controls the development of oligodendrocyte precursor cells
Authors: Lamprianou Smaragda , Chatzopoulou Elli , Thomas Jean-Léon , Bouyain Samuel , Harroch Sheila
Published: October 2011

The six members of the contactin (CNTN) family of neural cell adhesion molecules are involved in the formation and maintenance of the central nervous system (CNS) and have been linked to mental retardation and neuropsychiatric disorders such as autism. Five of the six CNTNs bind to the homologous receptor protein tyrosine phosphatases gamma (PTPRG) and zeta (PTPRZ), but the biological roles of these interactions remain unclear. We report here the cocrystal structure of the carbonic anhydrase-like domain of PTPRZ bound to tandem Ig repeats of CNTN1 and combine these structural data with binding assays to show that PTPRZ binds specifically to CNTN1 expressed at the surface of oligodendrocyte precursor cells. Furthermore, analyses of glial cell populations in wild-type and PTPRZ-deficient mice show that the binding of PTPRZ to CNTN1 expressed at the surface of oligodendrocyte precursor cells inhibits their proliferation and promotes their development into mature oligodendrocytes. Overall, these results implicate the PTPRZ/CNTN1 complex as a previously unknown modulator of oligodendrogenesis.
Ablation of a galectin preferentially expressed in adipocytes increases lipolysis, reduces adiposity, and improves insulin sensitivity in mice
Authors: Yang Ri-Yao , Yu Lan , Graham James L. , Hsu Daniel K. , Lloyd K. C. Kent , Havel Peter J. , Liu Fu-Tong
Published: October 2011

The breakdown of triglycerides, or lipolysis, is a tightly controlled process that regulates fat mobilization in accord with an animal's energy needs. It is well established that lipolysis is stimulated by hormones that signal energy demand and is suppressed by the antilipolytic hormone insulin. However, much still remains to be learned about regulation of lipolysis by intracellular signaling pathways in adipocytes. Here we show that galectin-12, a member of a β-galactoside–binding lectin family preferentially expressed by adipocytes, functions as an intrinsic negative regulator of lipolysis. Galectin-12 is primarily localized on lipid droplets and regulates lipolytic protein kinase A signaling by acting upstream of phosphodiesterase activity to control cAMP levels. Ablation of galectin-12 in mice results in increased adipocyte mitochondrial respiration, reduced adiposity, and ameliorated insulin resistance/glucose intolerance. This study identifies unique properties of this intracellular galectin that is localized to an organelle and performs a critical function in lipid metabolism. These findings add to the significant functions exhibited by intracellular galectins, and have important therapeutic implications for human metabolic disorders.
Thermodynamic basis for the genome to capsid charge relationship in viral encapsidation
Authors: Ting Christina L. , Wu Jianzhong , Wang Zhen-Gang
Published: October 2011

We establish an appropriate thermodynamic framework for determining the optimal genome length in electrostatically driven viral encapsidation. Importantly, our analysis includes the electrostatic potential due to the Donnan equilibrium, which arises from the semipermeable nature of the viral capsid, i.e., permeable to small mobile ions but impermeable to charged macromolecules. Because most macromolecules in the cellular milieu are negatively charged, the Donnan potential provides an additional driving force for genome encapsidation. In contrast to previous theoretical studies, we find that the optimal genome length is the result of combined effects from the electrostatic interactions of all charged species, the excluded volume and, to a very significant degree, the Donnan potential. In particular, the Donnan potential is essential for obtaining negatively overcharged viruses. The prevalence of overcharged viruses in nature may suggest an evolutionary preference for viruses to increase the amount of genome packaged by utilizing the Donnan potential (through increases in the capsid radius), rather than high charges on the capsid, so that structural stability of the capsid is maintained.
Cell culture model that mimics drusen formation and triggers complement activation associated with age-related macular degeneration
Authors: Johnson Lincoln V. , Forest David L. , Banna Christopher D. , Radeke Carolyn M. , Maloney Michelle A. , Hu Jane , Spencer Christine N. , Walker Aimee M. , Tsie Marlene S. , Bok Dean , Radeke Monte J. , Anderson Don H.
Published: October 2011

We introduce a human retinal pigmented epithelial (RPE) cell-culture model that mimics several key aspects of early stage age-related macular degeneration (AMD). These include accumulation of sub-RPE deposits that contain molecular constituents of human drusen, and activation of complement leading to formation of deposit-associated terminal complement complexes. Abundant sub-RPE deposits that are rich in apolipoprotein E (APOE), a prominent drusen constituent, are formed by RPE cells grown on porous supports. Exposure to human serum results in selective, deposit-associated accumulation of additional known drusen components, including vitronectin, clusterin, and serum amyloid P, thus suggesting that specific protein–protein interactions contribute to the accretion of plasma proteins during drusen formation. Serum exposure also leads to complement activation, as evidenced by the generation of C5b-9 immunoreactive terminal complement complexes in association with APOE-containing deposits. Ultrastructural analyses reveal two morphologically distinct forms of deposits: One consisting of membrane-bounded multivescicular material, and the other of nonmembrane-bounded particle conglomerates. Collectively, these results suggest that drusen formation involves the accumulation of sub-RPE material rich in APOE, a prominent biosynthetic product of the RPE, which interacts with a select group of drusen-associated plasma proteins. Activation of the complement cascade appears to be mediated via the classical pathway by the binding of C1q to ligands in APOE-rich deposits, triggering direct activation of complement by C1q, deposition of terminal complement complexes and inflammatory sequelae. This model system will facilitate the analysis of molecular and cellular aspects of AMD pathogenesis, and the testing of new therapeutic agents for its treatment.
Evidence of denser MgSiO3glass above 133 gigapascal (GPa) and implications for remnants of ultradense silicate melt from a deep magma ocean
Authors: Murakami Motohiko , Bass Jay D.
Published: October 2011

Ultralow velocity zones are the largest seismic anomalies in the mantle, with 10–30% seismic velocity reduction observed in thin layers less than 20–40 km thick, just above the Earth’s core-mantle boundary (CMB). The presence of silicate melts, possibly a remnant of a deep magma ocean in the early Earth, have been proposed to explain ultralow velocity zones. It is, however, still an open question as to whether such silicate melts are gravitationally stable at the pressure conditions above the CMB. Fe enrichment is usually invoked to explain why melts would remain at the CMB, but this has not been substantiated experimentally. Here we report in situ high-pressure acoustic velocity measurements that suggest a new transformation to a denser structure of MgSiO3glass at pressures close to those of the CMB. The result suggests that MgSiO3melt is likely to become denser than crystalline MgSiO3above the CMB. The presence of negatively buoyant and gravitationally stable silicate melts at the bottom of the mantle, would provide a mechanism for observed ultralow seismic velocities above the CMB without enrichment of Fe in the melt. An ultradense melt phase and its geochemical inventory would be isolated from overlying convective flow over geologic time.
Crystal structure of the octameric pore of staphylococcal γ-hemolysin reveals the β-barrel pore formation mechanism by two components
Authors: Yamashita Keitaro , Kawai Yuka , Tanaka Yoshikazu , Hirano Nagisa , Kaneko Jun , Tomita Noriko , Ohta Makoto , Kamio Yoshiyuki , Yao Min , Tanaka Isao
Published: October 2011

Staphylococcal γ-hemolysin is a bicomponent pore-forming toxin composed of LukF and Hlg2. These proteins are expressed as water-soluble monomers and then assemble into the oligomeric pore form on the target cell. Here, we report the crystal structure of the octameric pore form of γ-hemolysin at 2.5 Å resolution, which is the first high-resolution structure of a β-barrel transmembrane protein composed of two proteins reported to date. The octameric assembly consists of four molecules of LukF and Hlg2 located alternately in a circular pattern, which explains the biochemical data accumulated over the past two decades. The structure, in combination with the monomeric forms, demonstrates the elaborate molecular machinery involved in pore formation by two different molecules, in which interprotomer electrostatic interactions using loops connecting β2 and β3 (loop A: Asp43-Lys48 of LukF and Lys37-Lys43 of Hlg2) play pivotal roles as the structural determinants for assembly through unwinding of the N-terminal β-strands (amino-latch) of the adjacent protomer, releasing the transmembrane stem domain folded into a β-sheet in the monomer (prestem), and interaction with the adjacent protomer.