bluuebunny/crossref_metadata_2025 huggingface dataset:
Systems Modeling of Ammonia Borane Bead Reactor for Off-Board Regenerable Hydrogen Storage in PEM Fuel Cell Applications
Authors: Brooks Kriston , Devarakonda Maruthi , Rassat Scot , King Dale , Herling Darrell
Published: December 2010

Research on ammonia borane (AB, NH3BH3) has shown it to be a promising material for chemical hydrogen storage in PEM fuel cell applications. AB was selected by DOE’s Hydrogen Storage Engineering Center of Excellence (HSECoE) as the initial chemical hydride of study because of its high hydrogen storage capacity (up to 19.6% by weight for the release of three molar equivalents of hydrogen gas) and its stability under typical ambient conditions. A model of a bead reactor system was developed to study AB system performance in an automotive application and estimate the energy, mass, and volume requirements for this off-board regenerable hydrogen storage material. The system includes feed and product tanks, hot and cold augers, a ballast tank/reactor, a H2 burner and a radiator. One-dimensional models based on conservation of species and energy were used to predict important state variables such as reactant and product concentrations, temperatures of various components, flow rates, and pressure in the reactor system. The flow rate of AB into the process and the system pressure were governed by a control system which is modeled as an independent subsystem. Each subsystem in the model was coded as a C language S-function and implemented in the Matlab/Simulink environment. Preliminary system simulation results for a start-up case and for a transient drive cycle indicate appropriate trends in the reactor system dynamics.
Development and Testing of High Purity Alumina Ceramics for SOFC Stack Components
Authors: Zafred Paolo R. , Harrison Shay L. , Bolebruch Jeffrey J.
Published: December 2010

The successful attainment of many of the next generation Siemens SOFC Advanced Module features is dependent on development of key components required to provide fuel and process air to a stack of Delta cells. The overall objectives of this development effort included design and analysis of key stack components, fabrication of low cost net shape castings, characterization of high purity alumina ceramic material, and validation through full scale testing in Single and Multi-Cell Test Articles. The manufacturing process chosen for fabrication of stack components is a unique injection molding process referred to as the Blasch process. The Blasch process is a relatively low cost manufacturing process which allows for the fabrication of complex, close tolerance, near net shapes in a range of high alumina ceramic compositions without the need for expensive secondary machining. The Blasch process allows engineers to design virtually without restrictions related to other forming processes such as slip casting, extrusion, or pressing. The process utilizes nanotechnology to strongly bind together ceramic slurries containing one of a series of proprietary binders that can be activated by utilization of specific time/temperature processing. After casting into engineered molds, the binders in these slurries are caused to precipitate irreversibly and, upon firing, form a particularly thermal shock resistant ceramic bond containing no free silica. Ceramic shapes formed in this process shrink minimally and predictably, during firing, and therefore this is one of the few processes that can be claimed as true net shape manufacturing. Considerable effort went also in the development of a new class of failure tolerant alumina ceramics for SOFC stack components for service in reducing atmosphere at temperatures up to 1000°C. Pressureless infiltration of freeze cast alumina parts with chromium oxide was conducted to improve material’s strength. Strengthening of the porous alumina matrix is postulated to be a combination of both fracture toughness increase and crack size decrease, as a result of the infiltration process. Final results suggest that mechanical properties of infiltrated ceramics are superior to conventional porous freeze cast alumina material. This paper addresses the approach to ceramic castings design for SOFC stack components, the fabrication challenges with respect to shape complexity and the experimental tests performed to validate the material choice.
On-Line In-Situ Diagnostics of Processes Within PEM Fuel Cells by Raman Spectroscopy
Authors: Bettermann Hans , Fischer Peter
Published: December 2010

This contribution intends to show how Raman spectroscopy can be used to pursue processes inside PEM fuel cells. For this, two experimental setups have been worked out. At first a microscope objective was inserted into one bipolar plate. This enabled the detection of hydrogen, oxygen, nitrogen, vaporous and liquid water as well as changes in gas compositions and water distribution induced by an artificial pinhole within the MEA. A multiple-fiber Raman spectrometer with seven twin fibers was then developed to refine the look inside fuel cells. This setup permits the simultaneous record of gas compositions, liquid water and water vapor and how those species do change locally during operation. Beside the collection of data for modelling fuel cell processes, the multiple-fiber setup is primarily considered to monitor degradation processes and pre-stages of membrane damages.
Lost in Translation: Neuropsychiatric Drug Development
Authors: Becker Robert E. , Greig Nigel H.
Published: December 2010

The sluggish pace of development of new drugs for neuropsychiatric diseases can be attributed in part to faulty clinical trial design.
A Crisis of Public Confidence in Vaccines
Authors: Black Steven , Rappuoli Rino
Published: December 2010

This meeting report summarizes the outcome of a meeting held in July 2010 in Siena, Italy, to discuss the Crisis of Public Confidence in Vaccines.
The Cell Membrane as a Major Site of Damage during Aerosolization ofEscherichia coli
Authors: Thomas Richard J. , Webber Daniel , Hopkins Rebecca , Frost Andrew , Laws Thomas , Jayasekera Pramukh N. , Atkins Timothy
Published: December 2010

This study aimed to provide data on the survival and site of damage ofEscherichia colicells following aerosolization using two different techniques, nebulization and flow focusing. Four metabolic stains were assessed for their ability to detect respiratory activities and membrane homeostasis in aerosolizedE. colicells. The degree of sublethal injury increased significantly over the 10-min period of aerosolization inE. colicells aerosolized by using the Collison nebulizer, reaching up to 99.9% of the population. In contrast, a significantly lower proportion of the population was sublethally damaged during aerosolization using the flow-focusing aerosol generator (FFAG). Concomitantly, loss of membrane homeostasis increased at a higher rate in nebulized cells (68 to 71%) than in those aerosolized by using the FFAG (32 to 34%). The activities of respiratory enzymes decreased at increased rates in nebulized cells (27 to 37%) compared to the rates of decrease in cells aerosolized by using the FFAG (59 to 61%). The results indicate that the physiology of an aerosolized bacterium is linked to the method of aerosol generation and may affect the interpretation of a range of aerobiological phenomenon.
Diversion of Flux toward Sesquiterpene Production inSaccharomyces cerevisiaeby Fusion of Host and Heterologous Enzymes
Authors: Albertsen Line , Chen Yun , Bach Lars S. , Rattleff Stig , Maury Jerome , Brix Susanne , Nielsen Jens , Mortensen Uffe H.
Published: December 2010

The ability to transfer metabolic pathways from the natural producer organisms to the well-characterized cell factorySaccharomyces cerevisiaeis well documented. However, as many secondary metabolites are produced by collaborating enzymes assembled in complexes, metabolite production in yeast may be limited by the inability of the heterologous enzymes to collaborate with the native yeast enzymes. This may cause loss of intermediates by diffusion or degradation or due to conversion of the intermediate through competitive pathways. To bypass this problem, we have pursued a strategy in which key enzymes in the pathway are expressed as a physical fusion. As a model system, we have constructed several fusion protein variants in which farnesyl diphosphate synthase (FPPS) of yeast has been coupled to patchoulol synthase (PTS) of plant origin (Pogostemon cablin). Expression of the fusion proteins inS. cerevisiaeincreased the production of patchoulol, the main sesquiterpene produced by PTS, up to 2-fold. Moreover, we have demonstrated that the fusion strategy can be used in combination with traditional metabolic engineering to further increase the production of patchoulol. This simple test case of synthetic biology demonstrates that engineering the spatial organization of metabolic enzymes around a branch point has great potential for diverting flux toward a desired product.
Integrity of Proteins in Human Saliva after Sterilization by Gamma Irradiation
Authors: Ruhl Stefan , Berlenbach Pereshia , Langenfelder Sabine , Hörl Dagmar , Lehn Norbert , Hiller Karl-Anton , Schmalz Gottfried , Durchschlag Helmut
Published: December 2010

Microbial contamination of whole human saliva is unwanted for certain
in vitro
applications, e.g., when utilizing it as a growth substratum for biofilm experiments. The aim of this investigation was to test gamma irradiation for its suitability to sterilize saliva and to investigate the treatment's influence on the composition and integrity of salivary proteins in comparison to filter sterilization. For inhibition of bacterial growth by gamma irradiation, a sterility assurance level of 10
−6
was determined to be reached at a dose of 3.5 kGy. At this dose, the integrity of proteins, as measured by fluorescence, circular dichroism, and gel electrophoretic banding pattern, and the enzymatic activities of salivary amylase and lysozyme were virtually unchanged. Filtration reduced the total protein concentration to about half of its original value and decreased lysozyme activity to about 10%. It can be concluded that irradiation is suitable for sterilizing whole saliva in its native form.
Methanogenic Archaea Isolated from Taiwan's Chelungpu Fault
Authors: Wu Sue-Yao , Lai Mei-Chin
Published: December 2010

Terrestrial rocks, petroleum reservoirs, faults, coal seams, and subseafloor gas hydrates contain an abundance of diverse methanoarchaea. However, reports on the isolation, purification, and characterization of methanoarchaea in the subsurface environment are rare. Currently, no studies investigating methanoarchaea within fault environments exist. In this report, we succeeded in obtaining two new methanogen isolates, St545MbTof newly proposed speciesMethanolobus chelungpuianusandMethanobacterium palustreFG694aF, from the Chelungpu fault, which is the fault that caused a devastating earthquake in central Taiwan in 1999. Strain FG694aF was isolated from a fault gouge sample obtained at 694 m below land surface (mbls) and is an autotrophic, mesophilic, nonmotile, thin, filamentous-rod-shaped organism capable of using H2-CO2and formate as substrates for methanogenesis. The morphological, biochemical, and physiological characteristics and 16S rRNA gene sequence analysis revealed that this isolate belongs toMethanobacterium palustre.The mesophilic strain St545MbT, isolated from a sandstone sample at 545 mbls, is a nonmotile, irregular, coccoid organism that uses methanol and trimethylamine as substrates for methanogenesis. The 16S rRNA gene sequence of strain St545MbTwas 99.0% similar to that ofMethanolobus psychrophilusstrain R15 and was 96 to 97.5% similar to the those of otherMethanolobusspecies. However, the optimal growth temperature and total cell protein profile of strain St545MbTwere different from those ofM. psychrophilusstrain R15, and whole-genome DNA-DNA hybridization revealed less than 20% relatedness between these two strains. On the basis of these observations, we propose that strain St545MbT(DSM 19953T; BCRC AR10030; JCM 15159) be namedMethanolobus chelungpuianussp. nov. Moreover, the environmental DNA database survey indicates that bothMethanolobus chelungpuianusandMethanobacterium palustreare widespread in the subsurface environment.
mathFISH, a Web Tool That Uses Thermodynamics-Based Mathematical Models for
In Silico
Evaluation of Oligonucleotide Probes for Fluorescence
In Situ
Hybridization
Authors: Yilmaz L. Safak , Parnerkar Shreyas , Noguera Daniel R.
Published: December 2010

Mathematical models of RNA-targeted fluorescence
in situ
hybridization (FISH) for perfectly matched and mismatched probe/target pairs are organized and automated in web-based mathFISH (
http://mathfish.cee.wisc.edu
). Offering the users up-to-date knowledge of hybridization thermodynamics within a theoretical framework, mathFISH is expected to maximize the probability of success during oligonucleotide probe design.
Real-Time PCR Assay for
Clostridium perfringens
in Broiler Chickens in a Challenge Model of Necrotic Enteritis
Authors: Wu Shu-Biao , Rodgers Nicholas , Choct Mingan
Published: December 2010

We compared ileal
Clostridium perfringens
quantification results produced by real-time PCR and culture-based methods in broiler chickens in a challenge model of necrotic enteritis. Assessment of the relative standard deviations (RSDs) revealed that the real-time PCR assay generated a smaller standard deviation and thus was more precise than the culture-based method. Linear regression analysis indicated that the bacterial counts of these two methods were highly correlated (
R
2
= 0.845). We suggest that real-time PCR could be a replacement of the culture method for quantifying
C. perfringens
in the intestinal tracts of broiler chickens.
Bioluminescence-Based Method for Measuring Assimilable Organic Carbon in Pretreatment Water for Reverse Osmosis Membrane Desalination
Authors: Weinrich Lauren A. , Schneider Orren D. , LeChevallier Mark W.
Published: December 2010

A bioluminescence-based assimilable organic carbon (AOC) test was developed for determining the biological growth potential of seawater within the reverse osmosis desalination pretreatment process. The test uses
Vibrio harveyi
, a marine organism that exhibits constitutive luminescence and is nutritionally robust. AOC was measured in both a pilot plant and a full-scale desalination plant pretreatment.
Decomposition Rates and Residue-Colonizing Microbial Communities ofBacillus thuringiensisInsecticidal Protein Cry3Bb-Expressing (Bt) and Non-Bt Corn Hybrids in the Field
Authors: Xue Kai , Serohijos Raquel C. , Devare Medha , Thies Janice E.
Published: December 2010

Despite the rapid adoption of crops expressing the insecticidal Cry protein(s) fromBacillus thuringiensis(Bt), public concern continues to mount over the potential environmental impacts. Reduced residue decomposition rates and increased tissue lignin concentrations reported for some Bt corn hybrids have been highlighted recently as they may influence soil carbon dynamics. We assessed the effects of MON863 Bt corn, producing the Cry3Bb protein against the corn rootworm complex, on these aspects and associated decomposer communities by terminal restriction fragment length polymorphism (T-RFLP) analysis. Litterbags containing cobs, roots, or stalks plus leaves from Bt and unmodified corn with (non-Bt+I) or without (non-Bt) insecticide applied were placed on the soil surface and at a 10-cm depth in field plots planted with these crop treatments. The litterbags were recovered and analyzed after 3.5, 15.5, and 25 months. No significant effect of treatment (Bt, non-Bt, and non-Bt+I) was observed on initial tissue lignin concentrations, litter decomposition rate, or bacterial decomposer communities. The effect of treatment on fungal decomposer communities was minor, with only 1 of 16 comparisons yielding separation by treatment. Environmental factors (litterbag recovery year, litterbag placement, and plot history) led to significant differences for most measured variables. Combined, these results indicate that the differences detected were driven primarily by environmental factors rather than by any differences between the corn hybrids or the use of tefluthrin. We conclude that the Cry3Bb corn tested in this study is unlikely to affect carbon residence time or turnover in soils receiving these crop residues.
Bacterial Colonization of Pellet Softening Reactors Used during Drinking Water Treatment
Authors: Hammes Frederik , Boon Nico , Vital Marius , Ross Petra , Magic-Knezev Aleksandra , Dignum Marco
Published: December 2010

Pellet softening reactors are used in centralized and decentralized drinking water treatment plants for the removal of calcium (hardness) through chemically induced precipitation of calcite. This is accomplished in fluidized pellet reactors, where a strong base is added to the influent to increase the pH and facilitate the process of precipitation on an added seeding material. Here we describe for the first time the opportunistic bacterial colonization of the calcite pellets in a full-scale pellet softening reactor and the functional contribution of these colonizing bacteria to the overall drinking water treatment process. ATP analysis, advanced microscopy, and community fingerprinting with denaturing gradient gel electrophoretic (DGGE) analysis were used to characterize the biomass on the pellets, while assimilable organic carbon (AOC), dissolved organic carbon, and flow cytometric analysis were used to characterize the impact of the biological processes on drinking water quality. The data revealed pellet colonization at concentrations in excess of 500 ng of ATP/g of pellet and reactor biomass concentrations as high as 220 mg of ATP/m
3
of reactor, comprising a wide variety of different microorganisms. These organisms removed as much as 60% of AOC from the water during treatment, thus contributing toward the biological stabilization of the drinking water. Notably, only a small fraction (about 60,000 cells/ml) of the bacteria in the reactors was released into the effluent under normal conditions, while the majority of the bacteria colonizing the pellets were captured in the calcite structures of the pellets and were removed as a reusable product.
Functional Analysis of the Twin-Arginine Translocation Pathway in
Sodalis glossinidius
, a Bacterial Symbiont of the Tsetse Fly
Authors: De Vooght Linda , Caljon Guy , Coosemans Marc , Van Den Abbeele Jan
Published: December 2010

This study demonstrates a functional twin-arginine (Tat) translocation pathway present in the tsetse fly symbiont
Sodalis glossinidius
and its potential to export active heterologous proteins to the periplasm. Functionality was demonstrated using green fluorescent protein (GFP) fused to the Tat signal peptide of
Escherichia coli
trimethylamine
N
-oxide reductase (TorA).
Recombination Can Cause Telomere Elongations as Well as Truncations Deep within Telomeres in Wild-Type Kluyveromyces lactis Cells
Authors: Bechard Laura H. , Jamieson Nathan , McEachern Michael J.
Published: December 2010

In this study, we examined the role of recombination at the telomeres of the yeast
Kluyveromyces lactis
. We demonstrated that an abnormally long and mutationally tagged telomere was subject to high rates of telomere rapid deletion (TRD) that preferentially truncated the telomere to near-wild-type size. Unlike the case in
Saccharomyces cerevisiae
, however, there was not a great increase in TRD in meiosis. About half of mitotic TRD events were associated with deep turnover of telomeric repeats, suggesting that telomeres were often cleaved to well below normal length prior to being reextended by telomerase. Despite its high rate of TRD, the long telomere showed no increase in the rate of subtelomeric gene conversion, a highly sensitive test of telomere dysfunction. We also showed that the long telomere was subject to appreciable rates of becoming elongated substantially further through a recombinational mechanism that added additional tagged repeats. Finally, we showed that the deep turnover that occurs within normal-length telomeres was diminished in the absence of
RAD52
. Taken together, our results suggest that homologous recombination is a significant process acting on both abnormally long and normally sized telomeres in
K. lactis
.
Initial Cell Type Choice in Dictyostelium
Authors: Jang Wonhee , Gomer Richard H.
Published: December 2010

Much remains to be understood about how a group of cells break symmetry and differentiate into distinct cell types. The simple eukaryote
Dictyostelium discoideum
is an excellent model system for studying questions such as cell type differentiation.
Dictyostelium
cells grow as single cells. When the cells starve, they aggregate to develop into a multicellular structure with only two main cell types: spore and stalk. There has been a longstanding controversy as to how a cell makes the initial choice of becoming a spore or stalk cell. In this review, we describe how the controversy arose and how a consensus developed around a model in which initial cell type choice in
Dictyostelium
is dependent on the cell cycle phase that a cell happens to be in at the time that it starves.
FAD Binding by ApbE Protein from
Salmonella enterica
: a New Class of FAD-Binding Proteins
Authors: Boyd Jeffery M. , Endrizzi James A. , Hamilton Trinity L. , Christopherson Melissa R. , Mulder David W. , Downs Diana M. , Peters John W.
Published: December 2010

The periplasmic protein ApbE was identified through the analysis of several mutants defective in thiamine biosynthesis and was implicated as having a role in iron-sulfur cluster biosynthesis or repair. While mutations in
apbE
cause decreased activity of several iron-sulfur enzymes
in vivo
, the specific role of ApbE remains unknown. Members of the AbpE family include NosX and RnfF, which have been implicated in oxidation-reduction associated with nitrous oxide and nitrogen metabolism, respectively. In this work, we show that ApbE binds one FAD molecule per monomeric unit. The structure of ApbE in the presence of bound FAD reveals a new FAD-binding motif. Protein variants that are nonfunctional
in vivo
were generated by random and targeted mutagenesis. Each variant was substituted in the environment of the FAD and analyzed for FAD binding after reconstitution. The variant that altered a key tyrosine residue involved in FAD binding prevented reconstitution of the protein.
Spiral Architecture of the Nucleoid in
Bdellovibrio bacteriovorus
Authors: Butan Carmen , Hartnell Lisa M. , Fenton Andrew K. , Bliss Donald , Sockett R. Elizabeth , Subramaniam Sriram , Milne Jacqueline L. S.
Published: December 2010

We present a cryo-electron tomographic analysis of the three-dimensional architecture of a strain of the Gram-negative bacterium
Bdellovibrio bacteriovorus
in which endogenous MreB2 was replaced with monomeric teal fluorescent protein (mTFP)-labeled MreB2. In contrast to wild-type
Bdellovibrio
cells that predominantly displayed a compact nucleoid region, cells expressing mTFP-labeled MreB2 displayed a twisted spiral organization of the nucleoid. The more open structure of the MreB2-mTFP nucleoids enabled clear
in situ
visualization of ribosomes decorating the periphery of the nucleoid. Ribosomes also bordered the edges of more compact nucleoids from both wild-type cells and mutant cells. Surprisingly, MreB2-mTFP localized to the interface between the spiral nucleoid and the cytoplasm, suggesting an intimate connection between nucleoid architecture and MreB arrangement. Further, in contrast to wild-type cells, where a single tight chemoreceptor cluster localizes close to the single polar flagellum, MreB2-mTFP cells often displayed extended chemoreceptor arrays present at one or both poles and displayed multiple or inaccurately positioned flagella. Our findings provide direct structural evidence for spiral organization of the bacterial nucleoid and suggest a possible role for MreB in regulation of nucleoid architecture and localization of the chemotaxis apparatus.
A Transcriptional Regulator and ABC Transporters Link Stress Tolerance, (p)ppGpp, and Genetic Competence in
Streptococcus mutans
Authors: Seaton Kinda , Ahn Sang-Joon , Sagstetter Ann M. , Burne Robert A.
Published: December 2010

Streptococcus mutans
, a primary agent of dental caries, has three (p)ppGpp synthases: RelA, which is required for a mupirocin-induced stringent response; RelP, which produces (p)ppGpp during exponential growth and is regulated by the RelRS two-component system; and RelQ. Transcription of
relPRS
and a gene cluster (
SMu0835
to
SMu0837
) located immediately upstream was activated in cells grown with aeration and during a stringent response, respectively. Bioinformatic analysis predicted that
SMu0836
and
SMu0837
encode ABC exporters, which we designated
rcrPQ
(r
el
c
ompetence-
r
elated) genes, respectively.
SMu0835
(
rcrR
) encodes a MarR family transcriptional regulator. Reverse transcriptase PCR (RT-PCR) and quantitative RT-PCR analysis showed that RcrR functions as an autogenous negative regulator of the expression of the
rcrRPQ
operon. A mutant in which a polar insertion replaced the
SMu836
gene (Δ
836polar
) grew more slowly and had final yields that were lower than those of the wild-type strain. Likewise, the Δ
836polar
strain had an impaired capacity to form biofilms, grew poorly at pH 5.5, and was more sensitive to oxidative stressors. Optimal expression of
rcrPQ
required RelP and vice versa. Replacement of
rcrR
with a nonpolar antibiotic resistance marker (Δ
835np
), which leads to overexpression of
rcrPQ
, yielded a strain that was not transformable with exogenous DNA. Transcriptional analysis revealed that the expression of
comYA
and
comX
was dramatically altered in the Δ
835np
and Δ
836polar
mutants. Collectively, the data support the suggestion that the
rcrRPQ
gene products play a critical role in physiologic homeostasis and stress tolerance by linking (p)ppGpp metabolism, acid and oxidative stress tolerance, and genetic competence.
Genome-Wide Identification of
Mycobacterium tuberculosis
Exported Proteins with Roles in Intracellular Growth
Authors: McCann Jessica R. , McDonough Justin A. , Sullivan Jonathan Tabb , Feltcher Meghan E. , Braunstein Miriam
Published: December 2010

The exported proteins of
Mycobacterium tuberculosis
that are localized at the bacterial cell surface or secreted into the environment are ideally situated to interact with host factors and to function in virulence. In this study, we constructed a novel β-lactamase reporter transposon and used it directly in
M. tuberculosis
for genome-wide identification of exported proteins. From 177 β-lactam-resistant transposon mutants, we identified 111 different exported proteins. The majority of these proteins have no known function, and for nearly half of the proteins, our demonstration that they are exported when fused to a β-lactamase reporter is the first experimental proof of their extracytoplasmic localization. The transposon mutants in our banked library were of further value as a collection of mutants lacking individual exported proteins. By individually testing each of 111 mutants for growth in macrophages, six attenuated mutants with insertions in
mce1A
,
mce1B
,
mce2F
,
rv0199
,
ctaC
, and
lppX
were identified. Given that much of the
M. tuberculosis
genome encodes proteins of unknown function, our library of mapped transposon mutants is a valuable resource for efforts in functional genomics. This work also demonstrates the power of a β-lactamase reporter transposon that could be applied similarly to other bacterial pathogens.
Complete Genome Sequence of
Mycoplasma hyopneumoniae
Strain 168
Authors: Liu Wei , Feng Zhixin , Fang Liurong , Zhou Zhemin , Li Qiang , Li Sha , Luo Rui , Wang Lei , Chen Huanchun , Shao Guoqing , Xiao Shaobo
Published: December 2010

Mycoplasma hyopneumoniae
strain 168, a pathogenic strain prevalent in China, was isolated in 1974. Although this strain has been widespread for a long time, the genome sequence had not been determined. Here, we announce the complete genome sequence of
M. hyopneumoniae
strain 168.
Relating the Physical Properties of
Pseudomonas aeruginosa
Lipopolysaccharides to Virulence by Atomic Force Microscopy
Authors: Ivanov Ivan E. , Kintz Erica N. , Porter Laura A. , Goldberg Joanna B. , Burnham Nancy A. , Camesano Terri A.
Published: December 2010

Lipopolysaccharides (LPS) are an important class of macromolecules that are components of the outer membrane of Gram-negative bacteria such as
Pseudomonas aeruginosa
.
P
.
aeruginosa
contains two different sugar chains, the homopolymer common antigen (A band) and the heteropolymer O antigen (B band), which impart serospecificity. The characteristics of LPS are generally assessed after isolation rather than in the context of whole bacteria. Here we used atomic force microscopy (AFM) to probe the physical properties of the LPS of
P
.
aeruginosa
strain PA103 (serogroup O11)
in situ
. This strain contains a mixture of long and very long polymers of O antigen, regulated by two different genes. For this analysis, we studied the wild-type strain and four mutants, ΔWzz1 (producing only very long LPS), ΔWzz2 (producing only long LPS), DΔM (with both the
wzz1
and
wzz2
genes deleted), and Wzy::GM (producing an LPS core oligosaccharide plus one unit of O antigen). Forces of adhesion between the LPS on these strains and the silicon nitride AFM tip were measured, and the Alexander and de Gennes model of steric repulsion between a flat surface and a polymer brush was used to calculate the LPS layer thickness (which we refer to as length), compressibility, and spacing between the individual molecules. LPS chains were longest for the wild-type strain and ΔWzz1, at 170.6 and 212.4 nm, respectively, and these values were not statistically significantly different from one another. Wzy::GM and DΔM have reduced LPS lengths, at 34.6 and 37.7 nm, respectively. Adhesion forces were not correlated with LPS length, but a relationship between adhesion force and bacterial pathogenicity was found in a mouse acute pneumonia model of infection. The adhesion forces with the AFM probe were lower for strains with LPS mutations, suggesting that the wild-type strain is optimized for maximal adhesion. Our research contributes to further understanding of the role of LPS in the adhesion and virulence of
P
.
aeruginosa
.
HOW TO USE PILOT PROJECTS TO IMPLEMENT OPEN INNOVATION
Authors: BOSCHERINI LORENZO , CHIARONI DAVIDE , CHIESA VITTORIO , FRATTINI FEDERICO
Published: December 2010

Existing empirical research indicates that strong organizational barriers and inertia need to be overcome to ensure a smooth transition of a firm's approach to technological innovation from Closed to Open Innovation. The objective of the paper is to study how firms can identify, plan, and manage a pilot project so as to unfreeze the status quo and prepare the ground for a successful shift toward Open Innovation. Integrating existing literature in the field of innovation management, organizational change and project management, the paper develops a conceptual framework which identifies three steps a pilot project goes through (i.e. conception, realization and transfer of project's results) and the aspects that should be looked at along these stages so as to mobilize the organization and revolutionize its strategic approach to innovation management. These issues are investigated using a multiple case study involving 4 firms that can be considered as "early adopters" of Open Innovation in Italy. The paper provides several insights to R&D managers and Chief Technology Officers that will hopefully help them foresee and properly administer the organizational implications of adopting Open approaches to innovation management.
Melatonin differentially affects vascular blood flow in humans
Authors: Cook Jonathan S. , Sauder Charity L. , Ray Chester A.
Published: December 2010

Melatonin is synthesized and released into the circulation by the pineal gland in a circadian rhythm. Melatonin has been demonstrated to differentially alter blood flow to assorted vascular beds by the activation of different melatonin receptors in animal models. The purpose of the present study was to determine the effect of melatonin on blood flow to various vascular beds in humans. Renal (Doppler ultrasound), forearm (venous occlusion plethysmography), and cerebral blood flow (transcranial Doppler), arterial blood pressure, and heart rate were measured in 10 healthy subjects (29 ± 1 yr; 5 men and 5 women) in the supine position for 3 min. The protocol began 45 min after the ingestion of either melatonin (3 mg) or placebo (sucrose). Subjects returned at least 2 days later at the same time of day to repeat the trial after ingesting the other substance. Melatonin did not alter heart rate and mean arterial pressure. Renal blood flow velocity (RBFV) and renal vascular conductance (RVC) were lower during the melatonin trial compared with placebo (RBFV, 40.5 ± 2.9 vs. 45.4 ± 1.5 cm/s; and RVC, 0.47 ± 0.02 vs. 0.54 ± 0.01 cm·s−1·mmHg−1, respectively). In contrast, forearm blood flow (FBF) and forearm vascular conductance (FVC) were greater with melatonin compared with placebo (FBF, 2.4 ± 0.2 vs. 1.9 ± 0.1 ml·100 ml−1·min−1; and FVC, 0.029 ± 0.003 vs. 0.023 ± 0.002 arbitrary units, respectively). Melatonin did not alter cerebral blood flow measurements compared with placebo. Additionally, phentolamine (5-mg bolus) after melatonin reversed the decrease in RVC, suggesting that melatonin increases sympathetic outflow to the kidney to mediate renal vasoconstriction. In summary, exogenous melatonin differentially alters vascular blood flow in humans. These data suggest the complex nature of melatonin on the vasculature in humans.
Apoptosis in severe, compensated pressure overload predominates in nonmyocytes and is related to the hypertrophy but not function
Authors: Gelpi Ricardo J. , Park Misun , Gao Shumin , Dhar Sunil , Vatner Dorothy E. , Vatner Stephen F.
Published: December 2010

It is widely held that myocyte apoptosis in left ventricular hypertrophy (LVH) contributes to left ventricle (LV) dysfunction and heart failure. The main goal of this investigation was to determine if there is a statistical relationship among LV hypertrophy, apoptosis and LV function, and importantly whether the apoptosis occurs in myocytes or nonmyocytes in the heart. We used both rat and canine models of severe LVH induced by chronic thoracic aortic banding with resultant LV-aortic pressure gradients 145–155 mmHg and increases in LV/body weight of 58 and 70%. These models also provided the ability to examine transmural apoptosis in LVH. In both models, the overwhelming majority (88%) of apoptotic cells were nonmyocytes. The regressions for apoptosis vs. LVH were stronger for nonmyocytes than myocytes and also stronger in the subendocardium than the subepicardium. Importantly, LV systolic and diastolic wall stresses were normal, indicating that the apoptosis could not be attributed to LV stretch or heart failure. In addition, there was no relationship between the extent of apoptosis and LV ejection fraction, which actually increased ( P < 0.05), in the face of elevated LV systolic pressure, indicating that greater apoptosis did not result in a decrease in LV function. Thus, in response to chronic, severe pressure overload, LVH in the absence of LV dilation, and elevated LV wall stress, apoptosis occurred predominantly in nonmyocytes in the myocardial interstitium, more in the subendocardium than the subepicardium. The extent of apoptosis was linearly related to the amount of LV hypertrophy, but not to LV function.
Essential role of NF-κB and AP-1 transcription factors in TNF-α-induced TSLP expression in human airway smooth muscle cells
Authors: Redhu Naresh Singh , Saleh Ali , Halayko Andrew J. , Ali Aliyah S. , Gounni Abdelilah S.
Published: December 2010

Human airway smooth muscle (HASM) cells are a rich source of inflammatory mediators that may propagate the airway inflammatory responses. Recent studies from our laboratory and others demonstrate that HASM cells express the proallergic cytokine thymic stromal lymphopoietin (TSLP) in vitro and in vivo. Compelling evidence from in vitro studies and animal models suggest that the TSLP is a critical factor sufficient and necessary to induce or maintain the allergic airway inflammation. Despite of an immense interest in pathophysiology of TSLP in allergic inflammation, the triggers and mechanisms of TSLP expression remain inadequately understood. In this study, we found that TNF-α upregulates the TSLP mRNA and induces high levels of TSLP protein release in primary human ASM cells. Interestingly, TNF-α induced the TSLP promoter activity ( P < 0.05; n = 4) in HASM that was mediated by upstream NF-κB and activator protein-1 (AP-1) binding sites. Mutation in NF-κB and AP-1 binding sites completely abrogated the effect of TNF-α-mediated TSLP promoter activity and so did the expression of a dominant-negative mutant construct of IκB kinase. Furthermore, the peptide inhibitors of IκB kinase or NF-κB inhibited the TNF-α-induced TSLP protein release ( P < 0.05; n = 3) in HASM. Collectively, our data suggest a novel important biological role for NF-κB pathway in TNF-α-induced TSLP expression in HASM and recommend this as a prime target for anti-inflammatory drugs.
The Eye in the Neck: Removal of a Sewing Needle from the Posterior Pharyngeal Wall
Authors: Unadkat Samit N. , Talwar Rishi , Tolley Neil
Published: December 2010

Foreign body ingestion is a frequent presenting complaint to most emergency departments but the finding of a sewing needle in the posterior pharynx particularly is a rare finding. We report a case of a male patient with a sewing needle lodged in the posterior pharynx despite a history suggestive of chicken bone ingestion, absent clinical features, and negative flexible endoscopic examination. The needle was only identified through cervical spine radiographs. Even subsequent pharyngoscopy, laryngoscopy, and upper oesophagoscopy all proved to be unremarkable with the patient eventually requiring a left neck exploration to remove the needle. The case outlines the importance of simple radiography in suspected foreign body ingestion, even though clinical and endoscopic findings may be unremarkable.
Silibinin Prevents Lung Tumorigenesis in Wild-Type but not in iNOS−/− Mice: Potential of Real-Time Micro-CT in Lung Cancer Chemoprevention Studies
Authors: Ramasamy Kumaraguruparan , Dwyer-Nield Lori D. , Serkova Natalie J. , Hasebroock Kendra M. , Tyagi Alpna , Raina Komal , Singh Rana P. , Malkinson Alvin M. , Agarwal Rajesh
Published: December 2010

Purpose: Sustained nitric oxide (NO) generation positively correlates with lung cancer development and progression. Herein, we genetically confirmed this role of iNOS and evaluated the chemopreventive efficacy of silibinin in carcinogen-treated B6/129 wild-type (WT) and iNOS−/− mice.

Experimental Design: Male B6/129-Nos2tm1Lau (iNOS−/−) and B6/129PF2 WT mice were injected i.p. with 1 mg/g body weight urethane once weekly for 7 consecutive weeks, followed by silibinin gavage (742 mg/kg body weight) for 5 d/wk for 18 weeks.

Results: Quantification of micro-CT data in real-time showed that silibinin significantly decreases urethane-induced tumor number and size in WT mice, consistent with measurements made ex vivo at study termination. Genetic ablation of iNOS decreased urethane-induced tumor multiplicity by 87% (P < 0.001) compared to WT mice. Silibinin decreased tumor multiplicity by 71% (P < 0.01) in WT mice, but did not show any such considerable effect in iNOS−/− mice. Tumors from WT mice expressed more iNOS (P < 0.01) but almost similar eNOS and nNOS than those in silibinin-treated mice. In these tumors, silibinin moderately (P < 0.01) inhibited cell proliferation but strongly (P < 0.01) reduced the number of newly formed nestin-positive microvessels. Silibinin decreased VEGFR2 level, and STAT3 and NF-κB activation in tumors.

Conclusions: The lack of effect of silibinin in iNOS−/− mice suggests that silibinin exerts most of its chemopreventive and angiopreventive effects through its inhibition of iNOS expression in lung tumors. Our results support iNOS as a potential target for controlling lung cancer, and demonstrate the value of real-time noninvasive micro-CT imaging modality for evaluating the efficacy of lung cancer chemopreventive agents. Clin Cancer Res; 17(4); 1–9. ©2010 AACR.
MYC Amplification as a Prognostic Marker of Early-Stage Lung Adenocarcinoma Identified by Whole Genome Copy Number Analysis
Authors: Iwakawa Reika , Kohno Takashi , Kato Motohiro , Shiraishi Kouya , Tsuta Koji , Noguchi Masayuki , Ogawa Seishi , Yokota Jun
Published: December 2010

Purpose: Even in small-sized (≤2 cm in greatest dimension) and/or pathologic stage I lung adenocarcinoma (ADC), a considerable proportion of the patients will relapse within 5 years and show poor prognosis. The purpose of this study was to identify genetic alterations that define prognosis of patients with early-stage lung ADC.

Experimental Design: Regions of copy number alterations in 65 small-sized lung ADCs and 40 ADC cell lines were determined by using GeneChip Human Mapping 10-K and 250-K single-nucleotide polymorphism (SNP) arrays, respectively. A copy number assay based on real-time genomic PCR (RT-G-PCR) was done for 60 small-sized lung ADCs and 162 stage I lung ADCs.

Results: Several regions on chromosomes 5p, 7p, 8q, and 14q were frequently (>10%) amplified in both small-sized ADCs and lung ADC cell lines. In particular, the MYC gene was mapped in the minimum common region at chromosome 8q24.21, and therefore was indicated to be a target of gene amplification in lung ADCs. MYC amplification correlated with poor prognosis (P = 0.031) of patients with small-sized ADCs. MYC amplification detected by SNP array analysis was well reproduced by RT-G-PCR analysis. Therefore, to investigate the utility of MYC amplification as a prognostic marker for early-stage lung ADCs, 162 stage I lung ADCs were subjected to the analysis. MYC amplification was associated with relapse-free survival in these patients (P = 0.013 by multivariate Cox proportional hazard model analysis).

Conclusions: These results strongly indicate that MYC amplification is a prognostic marker of patients with early-stage lung ADCs. Clin Cancer Res; 17(6); 1481–9. ©2010 AACR.
Biophysical and Molecular Characterization of a Novel De Novo
KCNJ2
Mutation Associated With Andersen-Tawil Syndrome and Catecholaminergic Polymorphic Ventricular Tachycardia Mimicry
Authors: Barajas-Martinez Hector , Hu Dan , Ontiveros Gustavo , Caceres Gabriel , Desai Mayurika , Burashnikov Elena , Scaglione Jorge , Antzelevitch Charles
Published: December 2010

Background—

Mutations in
KCNJ2
, the gene encoding the human inward rectifier potassium channel Kir2.1 (I
K1
or I
Kir2.1
), have been identified in Andersen-Tawil syndrome. Andersen-Tawil syndrome is a multisystem inherited disease exhibiting periodic paralysis, cardiac arrhythmias, and dysmorphic features at times mimicking catecholaminergic polymorphic ventricular tachycardia.

Methods and Results—

Our proband displayed dysmorphic features including micrognathia, clinodactyly, and syndactyly and exhibited multiform extrasystoles and bidirectional ventricular tachycardia both at rest and during exercise testing. The patient's symptoms continued after administration of nadolol but subsided after treatment with flecainide. Molecular genetic screening revealed a novel heterozygous mutation (c.779G>C/p.R260P) in
KCNJ2
. Whole-cell patch-clamp studies conducted in TSA201 cells transfected with wild-type human
KCNJ2
cDNA (WT-
KCNJ2
) yielded robust I
Kir2.1
but no measurable current in cells expressing the R260P mutant. Coexpression of WT and R260P-
KCNJ2
(heterozygous expression) yielded a markedly reduced inward I
Kir2.1
compared with WT alone (−36.5±9.8 pA/pF versus −143.5±11.4 pA/pF, n=8 for both,
P
<0.001, respectively, at −90 mV), indicating a strong dominant negative effect of the mutant. The outward component of I
Kir2.1
measured at −50 mV was also markedly reduced with the heterozygous expression versus WT (0.52±5.5 pA/pF versus 23.4±6.7 pA/pF, n=8 for both,
P
<0.001, respectively). Immunocytochemical analysis indicates that impaired trafficking of R260P-
KCNJ2
channels.

Conclusions—

We report a novel de novo
KCNJ2
mutation associated with classic phenotypic features of Andersen-Tawil syndrome and catecholaminergic polymorphic ventricular tachycardia mimicry. The R260P mutation produces a strong dominant negative effect leading to marked suppression of I
K1
secondary to a trafficking defect.
Making Service Improvement Happen
Authors: McDermott Aoife M. , Keating Mary A.
Published: December 2010

This article illustrates the importance of social context in generating positive service improvement outcomes. Empirically, the qualitative research is based on a multilevel approach to theorizing from context. It considers the dimensions of the social and task contexts constraining and enabling service improvement in three Irish hospitals. Cross-sector case comparison (public, voluntary/nonprofit, and private sector) is used to consider the influence of task context, while attention to in-organization arrangements is used to consider the social context. The authors identify the influence of the task context on service improvement capacity and the influence of the social context on service improvement climate. Crucially, by taking account of service improvement outcomes, the authors identify both (a) the relative importance of the social context and (b) the impact of contextual configurations, through which the social context can either countervail or enhance task context effects. The findings suggest that organizations should focus on developing their social contexts to augment service improvement.
International consensus for a definition of disease flare in lupus
Authors: Ruperto N , Hanrahan LM , Alarcón GS , Belmont HM , Brey RL , Brunetta P , Buyon JP , Costner MI , Cronin ME , Dooley MA , Filocamo G , Fiorentino D , Fortin PR , Franks AG , Gilkeson G , Ginzler E , Gordon C , Grossman J , Hahn B , Isenberg DA , Kalunian KC , Petri M , Sammaritano L , Sánchez-Guerrero J , Sontheimer RD , Strand V , Urowitz M , von Feldt JM , Werth VP , Merrill JT
Published: December 2010

The Lupus Foundation of America (LFA) convened an international working group to obtain a consensus definition of disease flare in lupus. With help from the Paediatric Rheumatology International Trials Organization (PRINTO), two web-based Delphi surveys of physicians were conducted. Subsequently, the LFA held a second consensus conference followed by a third Delphi survey to reach a community-wide agreement for flare definition. Sixty-nine of the 120 (57.5%) polled physicians responded to the first survey. Fifty-nine of the responses were available to draft 12 preliminary statements, which were circulated in the second survey. Eighty-seven of 118 (74%) physicians completed the second survey, with an agreement of 70% for 9/12 (75%) statements. During the second conference, three alternative flare definitions were consolidated and sent back to the international community. One hundred and sixteen of 146 (79.5%) responded, with agreement by 71/116 (61%) for the following definition: “A flare is a measurable increase in disease activity in one or more organ systems involving new or worse clinical signs and symptoms and/or laboratory measurements. It must be considered clinically significant by the assessor and usually there would be at least consideration of a change or an increase in treatment.” The LFA proposes this definition for lupus flare on the basis of its high face validity.