bluuebunny/crossref_metadata_2025 huggingface dataset:
Transient Effects of Anesthetics on Dendritic Spines and Filopodia in the Living Mouse Cortex
Authors: Yang Guang , Chang Paul C. , Bekker Alex , Blanck Thomas J.J. , Gan Wen-Biao
Published: July 2011

Background

Anesthetics are widely used to induce unconsciousness, pain relief, and immobility during surgery. It remains unclear whether the use of anesthetics has significant and long-lasting effects on synapse development and plasticity in the brain. To address this question, the authors examined the formation and elimination of dendritic spines, postsynaptic sites of excitatory synapses, in the developing mouse cortex during and after anesthetics exposure.

Methods

Transgenic mice expressing yellow fluorescence protein in layer 5 pyramidal neurons were used in this study. Mice at 1 month of age underwent ketamine-xylazine and isoflurane anesthesia over a period of hours. The elimination and formation rates of dendritic spines and filopodia, the precursors of spines, were followed over hours to days in the primary somatosensory cortex using transcranial two-photon microscopy. Four to five animals were examined under each experimental condition. Student t test and Mann-Whitney U test were used to analyze the data.

Results

Administration of either ketamine-xylazine or isoflurane rapidly altered dendritic filopodial dynamics but had no significant effects on spine dynamics. Ketamine-xylazine increased filopodial formation whereas isoflurane decreased filopodial elimination during 4 h of anesthesia. Both effects were transient and disappeared within a day after the animals woke up.

Conclusion

Studies suggest that exposure to anesthetics transiently affects the dynamics of dendritic filopodia but has no significant effect on dendritic spine development and plasticity in the cortex of 1-month-old mice.
High Oxygen Partial Pressure Decreases Anemia-induced Heart Rate Increase Equivalent to Transfusion
Authors: Feiner John R. , Finlay-Morreale Heather E. , Toy Pearl , Lieberman Jeremy A. , Viele Maurene K. , Hopf Harriet W. , Weiskopf Richard B.
Published: July 2011

Background

Anemia is associated with morbidity and mortality and frequently leads to transfusion of erythrocytes. The authors sought to directly compare the effect of high inspired oxygen fraction versus transfusion of erythrocytes on the anemia-induced increased heart rate (HR) in humans undergoing experimental acute isovolemic anemia.

Methods

The authors combined HR data from healthy subjects undergoing experimental isovolemic anemia in seven studies performed by the group. HR changes associated with breathing 100% oxygen by nonrebreathing facemask versus transfusion of erythrocytes at their nadir hemoglobin concentration of 5 g/dl were examined. Data were analyzed using a mixed-effects model.

Results

HR had an inverse linear relationship to hemoglobin concentration with a mean increase of 3.9 beats per min per gram of hemoglobin (beats/min/g hemoglobin) decrease (95% CI, 3.7-4.1 beats/min/g hemoglobin), P < 0.0001. Return of autologous erythrocytes significantly decreased HR by 5.3 beats/min/g hemoglobin (95% CI, 3.8-6.8 beats/min/g hemoglobin) increase, P < 0.0001. HR at nadir hemoglobin of 5.6 g/dl (95% CI, 5.5-5.7 g/dl) when breathing air (91.4 beats/min; 95% CI, 87.6-95.2 beats/min) was reduced by breathing 100% oxygen (83.0 beats/min; 95% CI, 79.0-87.0 beats/min), P < 0.0001. The HR at hemoglobin 5.6 g/dl when breathing oxygen was equivalent to the HR at hemoglobin 8.9 g/dl when breathing air.

Conclusions

High arterial oxygen partial pressure reverses the heart rate response to anemia, probably because of its usability rather than its effect on total oxygen content. The benefit of high arterial oxygen partial pressure has significant potential clinical implications for the acute treatment of anemia and results of transfusion trials.
Single-step capture and sequencing of natural DNA for detection of BRCA1 mutations
Authors: Thompson John F. , Reifenberger Jeffrey G. , Giladi Eldar , Kerouac Kristen , Gill Jaime , Hansen Erik , Kahvejian Avak , Kapranov Philipp , Knope Travis , Lipson Doron , Steinmann Kathleen E. , Milos Patrice M.
Published: July 2011

Genetic testing for disease risk is an increasingly important component of medical care. However, testing can be expensive, which can lead to patients and physicians having limited access to the genetic information needed for medical decisions. To simplify DNA sample preparation and lower costs, we have developed a system in which any gene can be captured and sequenced directly from human genomic DNA without amplification, using no proteins or enzymes prior to sequencing. Extracted whole-genome DNA is acoustically sheared and loaded in a flow cell channel for single-molecule sequencing. Gene isolation, amplification, or ligation is not necessary. Accurate and low-cost detection of DNA sequence variants is demonstrated for the BRCA1 gene. Disease-causing mutations as well as common variants from well-characterized samples are identified. Single-molecule sequencing generates very reproducible coverage patterns, and these can be used to detect any size insertion or deletion directly, unlike PCR-based methods, which require additional assays. Because no gene isolation or amplification is required for sequencing, the exceptionally low costs of sample preparation and analysis could make genetic tests more accessible to those who wish to know their own disease susceptibility. Additionally, this approach has applications for sequencing integration sites for gene therapy vectors, transposons, retroviruses, and other mobile DNA elements in a more facile manner than possible with other methods.
Multiparameter Viability Assay for Stress Profiling Applied to the Food Pathogen Listeria monocytogenes F2365
Authors: Nocker Andreas , Caspers Martien , Esveld-Amanatidou Athina , van der Vossen Jos , Schuren Frank , Montijn Roy , Kort Remco
Published: July 2011

A novel generic approach for stress profiling was applied to
Listeria monocytogenes
strain F2365. This food-borne pathogen was exposed to gradients of five different stresses of increasing intensity, typically ranging from moderate to lethal conditions. The stress factors included heat, acidic pH, a detergent disinfectant, an oxidant, and hyperosmotic conditions. In addition to CFU counts and lag time, five different molecular viability parameters were measured by fluorescence-based assays, including membrane integrity, membrane potential, esterase activity, redox activity, and intracellular pH stability. The last was measured by our recently invented real-time viability assay. Exposure to all stresses resulted in clear dose-response relationships for all viability parameters with the exception of hyperosmotic conditions. A statistical analysis showed strong correlations for (i) the growth parameters plate counts and lag times, (ii) the enzyme-associated functions redox and esterase activity, and (iii) the membrane-associated pH stability and membrane integrity. Results indicated a pronounced difference in the susceptibilities of the measured parameters depending on the stress factor applied. However, at relatively high stress intensities, all of the viability parameters became affected independent of the stress factor. Applications of the approach presented here include studies on the mechanism of action of unknown compounds with biocidal activity and a comparative analysis of the severities of the impact of stress conditions of interest. It appears that a meaningful evaluation of the impact of mild stress conditions can be obtained only through measurement of multiple viability parameters.
A Limited Microbial Consortium Is Responsible for Extended Bioreduction of Uranium in a Contaminated Aquifer
Authors: Gihring Thomas M. , Zhang Gengxin , Brandt Craig C. , Brooks Scott C. , Campbell James H. , Carroll Susan , Criddle Craig S. , Green Stefan J. , Jardine Phil , Kostka Joel E. , Lowe Kenneth , Mehlhorn Tonia L. , Overholt Will , Watson David B. , Yang Zamin , Wu Wei-Min , Schadt Christopher W.
Published: July 2011

Subsurface amendments of slow-release substrates (e.g., emulsified vegetable oil [EVO]) are thought to be a pragmatic alternative to using short-lived, labile substrates for sustained uranium bioimmobilization within contaminated groundwater systems. Spatial and temporal dynamics of subsurface microbial communities during EVO amendment are unknown and likely differ significantly from those of populations stimulated by soluble substrates, such as ethanol and acetate. In this study, a one-time EVO injection resulted in decreased groundwater U concentrations that remained below initial levels for approximately 4 months. Pyrosequencing and quantitative PCR of 16S rRNA from monitoring well samples revealed a rapid decline in groundwater bacterial community richness and diversity after EVO injection, concurrent with increased 16S rRNA copy levels, indicating the selection of a narrow group of taxa rather than a broad community stimulation. Members of the
Firmicutes
family
Veillonellaceae
dominated after injection and most likely catalyzed the initial oil decomposition. Sulfate-reducing bacteria from the genus
Desulforegula
, known for long-chain fatty acid oxidation to acetate, also dominated after EVO amendment. Acetate and H
2
production during EVO degradation appeared to stimulate NO
3
−
, Fe(III), U(VI), and SO
4
2−
reduction by members of the
Comamonadaceae
,
Geobacteriaceae
, and
Desulfobacterales
. Methanogenic archaea flourished late to comprise over 25% of the total microbial community. Bacterial diversity rebounded after 9 months, although community compositions remained distinct from the preamendment conditions. These results demonstrated that a one-time EVO amendment served as an effective electron donor source for
in situ
U(VI) bioreduction and that subsurface EVO degradation and metal reduction were likely mediated by successive identifiable guilds of organisms.
Real-Time Detection and Identification of Chlamydophila Species in Veterinary Specimens by Using SYBR Green-Based PCR Assays
Authors: Nordentoft Steen , Kabell Susanne , Pedersen Karl
Published: July 2011

Infections caused by members of the
Chlamydiaceae
family have long been underestimated due to the requirement of special laboratory facilities for the detection of this group of intracellular pathogens. Furthermore, new studies of this group of intracellular pathogens have revealed that host specificity of different species is not as clear as recently believed. As most members of the genus
Chlamydophila
have shown to be transmissible from animals to humans, sensitive and fast detection methods are required. In this study, SYBR green-based real-time assays were developed that detect all members of
Chlamydiaceae
and differentiate the most prevalent veterinary
Chlamydophila
species:
Cp. psittaci
,
Cp. abortus
,
Cp. felis
, and
Cp. caviae
. By adding bovine serum albumin to the master mixes, target DNA could be detected directly in crude lysates of enzymatically digested conjunctival or pharyngeal swabs or tissue specimens from heart, liver, and spleen without further purification. The assays were evaluated on veterinary specimens where all samples were screened using a family-specific PCR, and positive samples were further tested using species-specific PCRs.
Cp. psittaci
was detected in 47 birds,
Cp. felis
was found in 10 cats,
Cp. caviae
was found in one guinea pig, and
Cp. abortus
was detected in one sheep. The screening assay appeared more sensitive than traditional microscopical examination of stained tissue smears. By combining a fast, robust, and cost-effective method for sample preparation with a highly sensitive family-specific PCR, we were able to screen for
Chlamydiaceae
in veterinary specimens and confirm the species in positive samples with additional PCR assays.
Changes in Diversity and Functional Gene Abundances of Microbial Communities Involved in Nitrogen Fixation, Nitrification, and Denitrification in a Tidal Wetland versus Paddy Soils Cultivated for Different Time Periods
Authors: Bannert Andrea , Kleineidam Kristina , Wissing Livia , Mueller-Niggemann Cornelia , Vogelsang Vanessa , Welzl Gerhard , Cao Zhihong , Schloter Michael
Published: July 2011

In many areas of China, tidal wetlands have been converted into agricultural land for rice cultivation. However, the consequences of land use changes for soil microbial communities are poorly understood. Therefore, we investigated bacterial and archaeal communities involved in inorganic nitrogen turnover (nitrogen fixation, nitrification, and denitrification) based on abundances and relative species richness of the corresponding functional genes along a soil chronosequence ranging between 50 and 2,000 years of paddy soil management compared to findings for a tidal wetland. Changes in abundance and diversity of the functional groups could be observed, reflecting the different chemical and physical properties of the soils, which changed in terms of soil development. The tidal wetland was characterized by a low microbial biomass and relatively high abundances of ammonia-oxidizing microbes. Conversion of the tidal wetlands into paddy soils was followed by a significant increase in microbial biomass. Fifty years of paddy management resulted in a higher abundance of nitrogen-fixing microbes than was found in the tidal wetland, whereas dominant genes of nitrification and denitrification in the paddy soils showed no differences. With ongoing rice cultivation, copy numbers of archaeal ammonia oxidizers did not change, while that of their bacterial counterparts declined. The
nirK
gene, coding for nitrite reductase, increased with rice cultivation time and dominated its functionally redundant counterpart,
nirS
, at all sites under investigation. Relative species richness showed significant differences between all soils with the exception of the archaeal ammonia oxidizers in the paddy soils cultivated for 100 and 300 years. In general, changes in diversity patterns were more pronounced than those in functional gene abundances.
Novel Virulent and Broad-Host-Range Erwinia amylovora Bacteriophages Reveal a High Degree of Mosaicism and a Relationship to Enterobacteriaceae Phages
Authors: Born Yannick , Fieseler Lars , Marazzi Janine , Lurz Rudi , Duffy Brion , Loessner Martin J.
Published: July 2011

A diverse set of 24 novel phages infecting the fire blight pathogenErwinia amylovorawas isolated from fruit production environments in Switzerland. Based on initial screening, four phages (L1, M7, S6, and Y2) with broad host ranges were selected for detailed characterization and genome sequencing. Phage L1 is a member of thePodoviridae, with a 39.3-kbp genome featuring invariable genome ends with direct terminal repeats. Phage S6, another podovirus, was also found to possess direct terminal repeats but has a larger genome (74.7 kbp), and the virus particle exhibits a complex tail fiber structure. Phages M7 and Y2 both belong to theMyoviridaefamily and feature long, contractile tails and genomes of 84.7 kbp (M7) and 56.6 kbp (Y2), respectively, with direct terminal repeats. The architecture of all four phage genomes is typical for tailed phages, i.e., organized into function-specific gene clusters. All four phages completely lack genes or functions associated with lysogeny control, which correlates well with their broad host ranges and indicates strictly lytic (virulent) lifestyles without the possibility for host lysogenization. Comparative genomics revealed that M7 is similar toE. amylovoravirus ΦEa21-4, whereas L1, S6, and Y2 are unrelated to any otherE. amylovoraphage. Instead, they feature similarities to enterobacterial viruses T7, N4, and ΦEcoM-GJ1. In a series of laboratory experiments, we provide proof of concept that specific two-phage cocktails offer the potential for biocontrol of the pathogen.
Determination of the Catalytic Base in Family 48 Glycosyl Hydrolases
Authors: Kostylev Maxim , Wilson David B.
Published: July 2011

The catalytic base in family 48 glycosyl hydrolases has not been previously established experimentally. Based on structural and modeling data published to date, we used site-directed mutagenesis and azide rescue activity assays to show definitively that the catalytic base in
Thermobifida fusca
Cel48A is aspartic acid 225. Of the tested mutants, only Cel48A with the D225E mutation retained partial activity on soluble and insoluble substrates. In azide rescue experiments, only the D225G mutation, in the smallest residue tested, showed an increase in activity with added azide.
Action at a Distance: Amino Acid Substitutions That Affect Binding of the Phosphorylated CheY Response Regulator and Catalysis of Dephosphorylation Can Be Far from the CheZ Phosphatase Active Site
Authors: Freeman Ashalla M. , Mole Beth M. , Silversmith Ruth E. , Bourret Robert B.
Published: July 2011

Two-component regulatory systems, in which phosphorylation controls the activity of a response regulator protein, provide signal transduction in bacteria. For example, the phosphorylated CheY response regulator (CheYp) controls swimming behavior. In
Escherichia coli
, the chemotaxis phosphatase CheZ stimulates the dephosphorylation of CheYp. CheYp apparently binds first to the C terminus of CheZ and then binds to the active site where dephosphorylation occurs. The phosphatase activity of the CheZ
2
dimer exhibits a positively cooperative dependence on CheYp concentration, apparently because the binding of the first CheYp to CheZ
2
is inhibited compared to the binding of the second CheYp. Thus, CheZ phosphatase activity is reduced at low CheYp concentrations. The CheZ21IT gain-of-function substitution, located far from either the CheZ active site or C-terminal CheY binding site, enhances CheYp binding and abolishes cooperativity. To further explore mechanisms regulating CheZ activity, we isolated 10 intragenic suppressor mutations of
cheZ21IT
that restored chemotaxis. The suppressor substitutions were located along the central portion of CheZ and were not allele specific. Five suppressor mutants tested biochemically diminished the binding of CheYp and/or the catalysis of dephosphorylation, even when the suppressor substitutions were distant from the active site. One suppressor mutant also restored cooperativity to CheZ21IT. Consideration of results from this and previous studies suggests that the binding of CheYp to the CheZ active site (not to the C terminus) is rate limiting and leads to cooperative phosphatase activity. Furthermore, amino acid substitutions distant from the active site can affect CheZ catalytic activity and CheYp binding, perhaps via the propagation of structural or dynamic perturbations through a helical bundle.
The Rickettsia prowazekii ExoU Homologue Possesses Phospholipase A
1
(PLA
1
), PLA
2
, and Lyso-PLA
2
Activities and Can Function in the Absence of Any Eukaryotic Cofactors
In Vitro
Authors: Housley Nicole A. , Winkler Herbert H. , Audia Jonathon P.
Published: July 2011

Here we have characterized the
Rickettsia prowazekii
RP534 protein, a homologue of the
Pseudomonas aeruginosa
ExoU phospholipase A (PLA) secreted cytotoxin. Our studies showed that purified recombinant RP534 PLA possessed the predicted PLA
2
and lyso-PLA
2
activities based on what has been published for
P. aeruginosa
ExoU. RP534 also displayed PLA
1
activity under the conditions tested, whereas ExoU did not. In addition, recombinant RP534 displayed a basal PLA activity that could hydrolyze phosphatidylcholine in the absence of any eukaryotic cofactors. Interestingly, the addition of bovine liver superoxide dismutase 1 (SOD1), a known activator of
P. aeruginosa
ExoU, resulted in an increased rate of RP534-catalyzed phospholipid hydrolysis, indicating that mechanisms of activation of the ExoU family of PLAs may be evolutionarily conserved. The mechanism of SOD1-dependent stimulation of RP534 was further examined using active site mutants and a fluorogenic phospholipid substrate whose hydrolysis by RP534 over a short time course is measureable only in the presence of SOD1. These studies suggest a mechanism by which SOD1 stimulates RP534 activity once it has bound to the substrate. We also show that antibody raised against RP534 was useful for immunoprecipitating active RP534 from
R. prowazekii
lysed cell extracts, thus verifying that this protein is expressed and active in rickettsiae isolated from embryonated hen egg yolk sacs.
The Heat-Resistant Agglutinin Family Includes a Novel Adhesin from Enteroaggregative Escherichia coli Strain 60A
Authors: Mancini Justin , Weckselblatt Brooke , Chung Yoonjie K. , Durante Julia C. , Andelman Steven , Glaubman Jessica , Dorff Justin D. , Bhargava Samhita , Lijek Rebeccah S. , Unger Katherine P. , Okeke Iruka N.
Published: July 2011

Heat-resistant agglutinin 1 (Hra1) is an accessory colonization factor of enteroaggregative
Escherichia coli
(EAEC) strain 042. Tia, a close homolog of Hra1, is an invasin and adhesin that has been described in enterotoxigenic
E. coli
. We devised a PCR-restriction fragment length polymorphism screen for the associated genes and found that they occur among 55 (36.7%) of the enteroaggregative
E. coli
isolates screened, as well as lower proportions of enterotoxigenic, enteropathogenic, enterohemorrhagic, and commensal
E. coli
isolates. Overall, 25%, 8%, and 3% of 150 EAEC strains harbored
hra1
alone,
tia
alone, or both genes, respectively. One EAEC isolate, 60A, produced an amplicon with a unique restriction profile, distinct from those of
hra1
and
tia
. We cloned and sequenced the full-length agglutinin gene from strain 60A and have designated it
hra2
. The
hra2
gene was not detected in any of 257 diarrheagenic
E. coli
isolates in our collection but is present in the genome of
Salmonella enterica
serovar Heidelberg strain SL476. The cloned
hra2
gene from strain 60A, which encodes a predicted amino acid sequence that is 64% identical to that of Hra1 and 68% identical to that of Tia, was sufficient to confer adherence on
E. coli
K-12. We constructed an
hra2
deletion mutant of EAEC strain 60A. The mutant was deficient in adherence but not autoaggregation or invasion, pointing to a functional distinction from the autoagglutinin Hra1 and the Tia invasin. Hra1, Tia, and the novel accessory adhesin Hra2 are members of a family of integral outer membrane proteins that confer different colonization-associated phenotypes.
Roles of the Redox-Active Disulfide and Histidine Residues Forming a Catalytic Dyad in Reactions Catalyzed by 2-Ketopropyl Coenzyme M Oxidoreductase/Carboxylase
Authors: Kofoed Melissa A. , Wampler David A. , Pandey Arti S. , Peters John W. , Ensign Scott A.
Published: July 2011

NADPH:2-ketopropyl-coenzyme M oxidoreductase/carboxylase (2-KPCC), an atypical member of the disulfide oxidoreductase (DSOR) family of enzymes, catalyzes the reductive cleavage and carboxylation of 2-ketopropyl-coenzyme M [2-(2-ketopropylthio)ethanesulfonate; 2-KPC] to form acetoacetate and coenzyme M (CoM) in the bacterial pathway of propylene metabolism. Structural studies of 2-KPCC from
Xanthobacter autotrophicus
strain Py2 have revealed a distinctive active-site architecture that includes a putative catalytic triad consisting of two histidine residues that are hydrogen bonded to an ordered water molecule proposed to stabilize enolacetone formed from dithiol-mediated 2-KPC thioether bond cleavage. Site-directed mutants of 2-KPCC were constructed to test the tenets of the mechanism proposed from studies of the native enzyme. Mutagenesis of the interchange thiol of 2-KPCC (C82A) abolished all redox-dependent reactions of 2-KPCC (2-KPC carboxylation or protonation). The air-oxidized C82A mutant, as well as wild-type 2-KPCC, exhibited the characteristic charge transfer absorbance seen in site-directed variants of other DSOR enzymes but with a pK
a
value for C87 (8.8) four units higher (i.e., four orders of magnitude less acidic) than that for the flavin thiol of canonical DSOR enzymes. The same higher pK
a
value was observed in native 2-KPCC when the interchange thiol was alkylated by the CoM analog 2-bromoethanesulfonate. Mutagenesis of the flavin thiol (C87A) also resulted in an inactive enzyme for steady-state redox-dependent reactions, but this variant catalyzed a single-turnover reaction producing a 0.8:1 ratio of product to enzyme. Mutagenesis of the histidine proximal to the ordered water (H137A) led to nearly complete loss of redox-dependent 2-KPCC reactions, while mutagenesis of the distal histidine (H84A) reduced these activities by 58 to 76%. A redox-independent reaction of 2-KPCC (acetoacetate decarboxylation) was not decreased for any of the aforementioned site-directed mutants. We interpreted and rationalized these results in terms of a mechanism of catalysis for 2-KPCC employing a unique hydrophobic active-site architecture promoting thioether bond cleavage and enolacetone formation not seen for other DSOR enzymes.
An Integrated Proteomics/Transcriptomics Approach Points to Oxygen as the Main Electron Sink for Methanol Metabolism in Methylotenera mobilis
Authors: Beck David A. C. , Hendrickson Erik L. , Vorobev Alexey , Wang Tiansong , Lim Sujung , Kalyuzhnaya Marina G. , Lidstrom Mary E. , Hackett Murray , Chistoserdova Ludmila
Published: July 2011

Methylotenera
species, unlike their close relatives in the genera
Methylophilus
,
Methylobacillus
, and
Methylovorus
, neither exhibit the activity of methanol dehydrogenase nor possess
mxaFI
genes encoding this enzyme, yet they are able to grow on methanol. In this work, we integrated a genome-wide proteomics approach, shotgun proteomics, and a genome-wide transcriptomics approach, shotgun transcriptome sequencing (RNA-seq), of
Methylotenera mobilis
JLW8 to identify genes and enzymes potentially involved in methanol oxidation, with special attention to alternative nitrogen sources, to address the question of whether nitrate could play a role as an electron acceptor in place of oxygen. Both proteomics and transcriptomics identified a limited number of genes and enzymes specifically responding to methanol. This set includes genes involved in oxidative stress response systems, a number of oxidoreductases, including XoxF-type alcohol dehydrogenases, a type II secretion system, and proteins without a predicted function. Nitrate stimulated expression of some genes in assimilatory nitrate reduction and denitrification pathways, while ammonium downregulated some of the nitrogen metabolism genes. However, none of these genes appeared to respond to methanol, which suggests that oxygen may be the main electron sink during growth on methanol. This study identifies initial targets for future focused physiological studies, including mutant analysis, which will provide further details into this novel process.
Human NK Cells Are Alerted to Induction of p53 in Cancer Cells by Upregulation of the NKG2D Ligands ULBP1 and ULBP2
Authors: Textor Sonja , Fiegler Nathalie , Arnold Annette , Porgador Angel , Hofmann Thomas G. , Cerwenka Adelheid
Published: July 2011

Natural killer (NK) cells are immune cells sensing and eliminating foreign, stressed, transformed, and senescent cells through specialized surface receptors, such as NKG2D, that interacts with several virus- or stress-inducible ligands, including ULBP1 and -2, which are expressed on target cell surfaces. For example, induction of DNA damage or cellular senescence pathways in tumor cells led to upregulation of NKG2D ligands that activate NK cells. Although, both pathways activate p53, the relationship of p53 activation to upregulation of NKG2D ligands has not been addressed. In this study, we report that induction of wild-type p53, but not mutant p53, strongly upregulated mRNA and cell surface expression of ULBP1 and -2, whereas expression of other NK cell ligands was not affected. We defined intronic p53-responsive elements in these two novel p53 target genes. Coculture of wild-type p53-induced human tumor cells with primary human NK cells enhanced NKG2D-dependent degranulation and IFN-γ production by NK cells. Accordingly, treatment of certain wild-type p53-expressing tumor cell lines with the p53-reactivating small molecular compound RITA resulted in upregulation of ULBP2 mRNA and cell surface protein expression. Taken together, our findings define the involvement of p53 in the regulation of specific NKG2D ligands that enhance NK cell–mediated target recognition. One implication of our work is that activating p53 after adoptive transfer of NK cells might constitute an effective combinatorial strategy of NK cell–based immunochemotherapy in cancers in which wild-type p53 function is preserved. Cancer Res; 71(18); 5998–6009. ©2011 AACR.
Effect of cement matrix and composite thickness on properties of 2-2 type cement-based piezoelectric composites
Authors: Dongyu Xu  , Xin Cheng  , Shifeng Huang  , Minhua Jiang
Published: July 2011

In this study, 2-2 type cement-based piezoelectric composites were fabricated by dice-and-fill technique. The effects of cement matrix and composite thickness on electrical and acoustic properties of the composite were analyzed. The results show that all the 2-2 type cement-based piezoelectric composites using different kinds of cement as matrix have superior piezoelectric and electromechanical properties. Cement matrix has little influence on the acoustic impedance of the composites, which fluctuates between 13.68 and 15.84 M rayl. With decreasing composite thickness, the piezoelectric strain factor d33, the dielectric factor ερ, and dielectric loss tan δ of the composites decrease, while the piezoelectric voltage factor g33, the thickness electromechanical coupling coefficient Kt, and the mechanical quality factor Qm increase. The acoustic impedance of the composites fluctuates around 14 M rayl with increasing the composite thickness, which is obviously less than that of the pure piezoelectric ceramic. Therefore, 2-2 type cement-based piezoelectric sensors suitable for civil engineering structure can be easily tailored by adjusting the composite thickness.
Who Are We?
Authors: Ran Bing , Golden Timothy J.
Published: July 2011

Using Pennsylvania State University’s responses to an identity threat, this article discusses the social construction of organizational identity as a negotiated outcome between various stakeholders. The authors propose four main characteristics of the social construction of organizational identity—intentional, temporal, relational, and external—that extend Ran and Duimering’s demarcation of two identity construction processes: the linguistic and the social construction. The authors also provide some guidance for public institutions, universities, or nonprofit organizations as they construct, maintain, and negotiate a positive identity in the context of threatening changes.
Civic Engagement and Internet Use in Local Governance
Authors: Kim B. Joon , Kavanaugh Andrea L. , Hult Karen M.
Published: July 2011

Civically and politically interested individuals often use the Internet to facilitate and augment their civic and political participation. At the local level, such people also use the Internet to communicate and share information with fellow members of the local community groups to which they belong. In doing so, local groups help to create awareness and draw citizens into public deliberation about local issues and concerns, not only offline (a role they have played for many years) but also online. This research examines the interplay of individual-level and local group-level factors through an analysis of household survey data from the town of Blacksburg, Virginia, and surrounding areas in 2005 and 2006. It seeks to reconcile different levels of analysis—individual and group levels—relating to the use and impact of the Internet on civic engagement. This study identifies the distinctive influences at both the individual level and the community group level by applying a multilevel statistical model (specifically, the hierarchical linear model). First, at the individual level of analysis, this study found that internal and external political efficacy and community collective efficacy were significant individual-level factors explaining the Internet use for civic and political purposes. Second, at the group level of analysis, community group Internet use—which includes listservs, discussion forums, and blogs, among other emerging Internet technologies—and group political discussion were revealed as key influences on citizens’ perspectives on the helpfulness of the Internet for civic and political purposes. Finally, in multilevel analysis, when taking individual-level variables into account, the group-level variables (group Internet use and group political discussion and interests) are positively associated with the views of the helpfulness of the Internet in connecting with others in the community and becoming more involved in local issues.
The Impact of Nonaudit Services on Capital Markets
Authors: Nam Seunghan , Ronen Joshua
Published: July 2011

The framers of the Sarbanes–Oxley Act (SOX) presume that nonaudit services (NASs) lower the quality of financial statements, so they have prohibited auditors from offering most NASs. In addition, regulators believe that NASs may cause the auditor to be perceived as “dependent” in appearance, thus increasing information risk, even if they have no impact on the quality of financial statements. The authors investigate two hypotheses using pre-SOX data. First, they ask whether the proportion of NASs fees to total fees has a positive or negative association with the ability of financial statements to predict a firm’s future cash flows, which can be considered a measure of the quality of the statements. Second, they ask whether the proportion has a negative or positive association with the cost of capital (COC) and the bid/ask spread, controlling for the predictability. The COC and the bid/ask spread serve as proxies for information risk. Contrary to the proponents of prohibiting NAS, the authors find that the proportion of NASs fees to total fees has a positive association with predictability. Controlling for the quality of financial statements, NASs still have a negative association with the COC and the bid/ask spread as proxies for information risk. These findings suggest that NASs improve the quality of financial statements and reduce information risk.
The Impact of IFRS on Accounting Quality in a Regulated Market
Authors: Liu Chunhui , Yao Lee J. , Hu Nan , Liu Ling
Published: July 2011

As more countries consider the adoption of International Financial Reporting Standards (IFRS) that are based on practices prevalent in the English-speaking countries with free markets, it’s increasingly important to understand the impact of IFRS on countries of different institutional, economic, and political environments. This article reports a study that examines the impact of IFRS on accounting quality in a regulated market, China, where new substantially IFRS-convergent accounting standards became mandatory for listed firms in 2007. Accounting quality is examined for the period 2005 to 2008 with only firms mandated to follow the new standards. The empirical results generally indicate that accounting quality improved with decreased earnings management and increased value relevance of accounting measures in China since 2007. Firms audited by the Big Four are expected to have higher quality before the standard change evidenced quality improvement to a smaller extent. Further analysis shows that such changes are less likely to result from changes in economic conditions but from the changes of the standards. Through the analysis of China’s adoption of the new substantially IFRS-convergent standards, the study provides direct evidence on the question of whether IFRS can be relevant to markets that are still disciplined mainly by regulators rather than by market mechanisms.
The Effect of Varied Conductor Preparatory Gestures on Singer Upper Body Movement
Authors: Manternach Jeremy N.
Published: July 2011

This study was designed to examine the effect of five conductor preparatory gestures on indirect measurements of individual singers’ ( N = 60) head and shoulder movements at two junctures as they sang a familiar melody. To inform music teacher preparation, the preparatory gestures were chosen to test various recommendations made by choral conducting instructors. Among primary results: (a) participant head movement significantly increased when the conductor modeled upward head movement; (b) participant shoulder movement significantly increased when the conductor modeled upward shoulder movement; (c) participant shoulder movement increased during a downward moving gesture as compared to an upward moving gesture; and (d) participant head and shoulder measurements differed between the initial breath and the internal breath taken in the melody. These results were discussed in terms of choral conducting pedagogy and music teacher preparation.
A Comparison of the Cyclic Variation in Serum Levels of CA125 Across the Menstrual Cycle Using Two Commercial Assays
Authors: McLemore Monica R. , Aouizerat Bradley E. , Lee Kathryn A. , Chen Lee-may , Cooper Bruce , Tozzi Michael , Miaskowski Christine
Published: July 2011

Background: Clinicians use CA125, a tumor-associated antigen, primarily to monitor epithelial ovarian cancer. However, CA125 lacks the sensitivity and specificity necessary for population-based screening in healthy women. The purpose of this study was to determine if serum concentrations of CA125 differed across the three phases of the menstrual cycle in healthy, premenopausal women using two commercially available assays. Methods: Healthy, Caucasian women between the ages of 18 and 39 were enrolled using strict criteria to exclude factors known to contribute to CA125 fluctuations. Menstrual cycle regularity was determined using calendars maintained by participants for 3 months. After cycle regularity was established, blood was drawn at three time points for CA125 determination using two commercial assays (i.e., Siemens and Panomics). Results: Regardless of the assay used, CA125 values were highest during menses. The CA125 values decreased 0.2 U/ml per day from menses to the end of the same cycle, which resulted in a net decrease of 5.8 U/ml across the cycle. Conclusions: The two commercial assays for CA125 determination demonstrated good concordance in terms of reference ranges regardless of epitope differences. While CA125 levels changed over the course of the menstrual cycle, these changes may not be clinically significant in healthy women. This study is the first to control for factors known to contribute to CA125 elevations; to quantify a decrease in CA125 levels across the menstrual cycle; and to confirm concordance in the relative decreases in serum CA125 levels across the menstrual cycle between two frequently used commercial assays.
Effect of Self-Management Intervention on Cortisol and Daily Stress Levels in Irritable Bowel Syndrome
Authors: Deechakawan Wimon , Cain Kevin C. , Jarrett Monica E. , Burr Robert L. , Heitkemper Margaret M.
Published: July 2011

Self-management programs that include cognitive behavioral strategies have been shown to improve gastrointestinal (GI) symptoms, psychological distress, and quality of life (QoL) in persons with irritable bowel syndrome (IBS). However, less is known about the physiological impact of such a change. As part of a randomized controlled trial using a comprehensive self-management (CSM) intervention ( n = 126) compared to usual care (UC; n = 62), cortisol levels were measured in 4 weekly first morning urine samples at baseline and at 3-, 6-, and 12-month follow-up. In addition, diary (28 days) ratings of stress were recorded at baseline, 3, 6, and 12 months. The omnibus test of all three outcome times showed no differences in urine cortisol levels between the CSM and UC groups ( p = .400); however, at 3 months the CSM group had significantly higher cortisol levels than the UC group ( p = .012). The CSM group reported lower daily stress levels ( p = .046 from the omnibus test of all 3 time points) than the UC group, with the effect getting stronger over time. Despite marked improvements in reported stress and previously reported GI and psychological distress symptoms at later follow-ups, the CSM program did not reduce urine cortisol levels in adults with IBS. These results suggest that the first-void urine cortisol levels are not reflective of self-reported daily stress in this patient population.
Aminopeptidase Activity Profile in Cultured Human Osteoblasts
Authors: Lucena Gema , Reyes-Botella Candela , García-Martínez Olga , Díaz-Rodríguez Lourdes , Alba Francisco , Ruiz Concepción
Published: July 2011

Aminopeptidases (APs) are enzymes involved in a wide variety of biological processes and present in a variety of different cell populations. The authors studied these enzymes in primary cultured human osteoblasts in order to establish an activity profile and thereby contribute to knowledge of bone tissue. The authors used 13 different substrates ( N-terminal amino acids) and a fluorimetric assay to examine AP activity associated with the membranes of cultured osteoblasts. The authors demonstrated activity > 10 pmol/min/104 cells when glycine, alanine, leucine, arginine, phenylalanine, methionine, and lysine were used as substrates. The activity was markedly lower (<1.6 pmol/min/104 cells) when the other N-terminal amino acids were used. Puromycin and bestatin inhibited AP activity, though not completely, when we used AlaNA or LeuNA as substrates. Further studies are warranted to determine the role of these enzymes in bone tissue physiology.
‘‘When Keeping it Real Goes Wrong’’: Resident Evil 5, Racial Representation, and Gamers
Authors: Brock André
Published: July 2011

Videogames’ ability to depict cultural iconographies and characters have occasionally led to accusations of insensitivity. This article examines gamers’ reactions to a developer’s use of Africans as enemies in a survival horror videogame, Resident Evil 5. Their reactions offer insight into how videogames represent Whiteness and White privilege within the social structure of ‘‘play.’’ Omi and Winant’s (1994) racial formation theory notes that race is formed through cultural representations of human bodies organized in social structures. Accordingly, depictions of race in electronic spaces rely upon media imagery and social interactions. Videogames construct exotic fantasy worlds and peoples as places for White male protagonists to conquer, explore, exploit, and solve. Like their precursors in science fiction, fantasy, and horror, videogame narratives, activities, and players often draw from Western values of White masculinity, White privilege as bounded by conceptions of ‘‘other,’’ and relationships organized by coercion and domination.
The Promise of Play: A New Approach to Productive Play
Authors: Lindtner Silvia , Dourish Paul
Published: July 2011

Games are woven into webs of cultural meaning, social connection, politics, and economic change. This article builds on previous work in cultural, new media, and game studies to introduce a new approach to productive play, the promise of play. This approach analyzes games as sites of cultural production in times of increased transnational mediation and speaks to the formation of identity across places. The authors ground their explorations in findings from ethnographic research on gaming in urban China. The spread of Internet access and increasing popularity of digital entertainment in China has been used as an indicator of social change and economic progress shaped by global flows. It has also been described as being limited by local forces such as tight information control. As such, gaming technologies in China are ideal to ask broader questions about digital media as sites of production at the intersection of local contingencies and transnational developments.
A perspective on the future public health practitioner
Authors: Hanlon Phil , Carlisle Sandra , Hannah Margaret , Lyon Andrew , Reilly David
Published: July 2011

In the centuries following the Enlightenment, scientific and technological developments gave ‘modern people’ an unprecedented ability to understand, predict and control the natural world. This has brought health and social benefits unimaginable to our ancestors and sets us apart from all previous generations. Yet there is a wide-ranging body of evidence that suggests that modernity is now in decline, largely because its methods and mindset are increasingly recognized as unsustainable. Problems are manifest in the emergence of new public health epidemics such as obesity and addictive behaviours, the loss of well-being and increase in anxiety and depression in affluent society, and the persistence of ever-widening health and social inequalities at national and global levels. Still larger problems now confront us, such as climate change, peak oil and the loss of biodiversity, all of which are linked to the ‘modern’ way of life. We are potentially faced with the collapse of certain aspects of modern society: we are certainly faced with the prospect of inevitable change. While the broad public health community has an important role to play in developing workable solutions to such daunting problems, we argue that some profound changes will be needed in order for us to cope successfully. No blueprints for dealing with change exist, which means that we will need to learn our way into the future. In this paper we take a perspective on the role and nature of the future practitioner in public health and health promotion. We argue that future practitioners will need to develop new ways of thinking, being and doing; new perspectives and new forms of understanding the world. We believe our discipline – and people generally – to be capable of such development, as insights from multiple sources tell us that human nature is malleable, not fixed. We use this analysis to trace, as examples, the imagined lives of five women living in different eras over the course of history in a Western society, and the emergence of different mindsets or worldviews, as the social, economic and cultural context changes. Post-modern analysts might insist that we have no basis for making value judgements between such different worldviews. In this paper, however, we argue that future practitioners should be empathetic to different views and willing to move beyond them, as necessary. We will need to learn and develop in ways that are compatible with our intrinsic needs as human beings and the needs of our ecosystem. We conclude by suggesting just some of the supportive processes of change needed in mapping out a more sustainable future for the public health community.
Incidence of a first thromboembolic event in asymptomatic carriers of high-risk antiphospholipid antibody profile: a multicenter prospective study
Authors: Pengo Vittorio , Ruffatti Amelia , Legnani Cristina , Testa Sophie , Fierro Tiziana , Marongiu Francesco , De Micheli Valeria , Gresele Paolo , Tonello Marta , Ghirarduzzi Angelo , Bison Elisa , Denas Gentian , Banzato Alessandra , Padayattil Jose Seena , Iliceto Sabino
Published: July 2011

Persistent antiphospholipid (aPL) antibodies are occasionally found in subjects without prior history of thromboembolic events (TEs), raising the dilemma of whether to initiate or not a primary thromboprophylaxis. A first TE is considered rare in aPL carriers, but previous studies did not consider the aPL profile nor was the test positivity confirmed in a reference laboratory. In this study, 104 subjects with high-risk aPL profile (positive lupus anticoagulant, anticardiolipin, and anti-β2–glycoprotein I antibodies, triple positivity) confirmed in a reference laboratory, were followed up for a mean of 4.5 years. There were 25 first TEs (5.3% per year): the cumulative incidence after 10 years was 37.1% (95% confidence interval [CI], 19.9%-54.3%). On multivariate analysis, male sex (hazard ratio = 4.4; 95% CI, 1.5-13.1, P = .007) and risk factors for venous thromboembolism (hazard ratio = 3.3; 95% CI, 1.3-8.5, P = .01) were independent predictors for TEs. Aspirin did not significantly affect the incidence of TE. In conclusion, the occurrence of a first TE in carriers of high-risk aPL profile is considerable; it is more frequent among male subjects and in the presence of additional risk factors for venous TE. These data can help in the decision to initiate primary thromboprophylaxis in these subjects.