bluuebunny/crossref_metadata_2025 huggingface dataset:
Functionally Redundant Cellobiose-Degrading Soil Bacteria Respond Differentially to Oxygen
Authors: Schellenberger Stefanie , Drake Harold L. , Kolb Steffen
Published: July 2011

The availability of oxygen (O
2
) in aerated (i.e., water-unsaturated) soils affects the metabolic activities of aerobic and anaerobic soil prokaryotes that degrade plant-derived saccharides. Fluctuating availabilities of O
2
were imposed on agricultural soil slurries supplemented with cellobiose. Slurries were subjected to oxic conditions (48 h), followed by an anoxic period (120 h) and a final oxic period (24 h). Redox potential was stable at 500 mV during oxic periods but decreased rapidly (within 10 h) under anoxic conditions to −330 mV. The consumption of cellobiose occurred without apparent delay at all redox potentials. The metabolic activities of seven previously identified saccharolytic family-level taxa of the investigated soil were measured with newly designed quantitative PCR assays targeting the 16S rRNA. Four taxa responded to the experimental conditions. The amounts of rRNAs of
Micrococcaceae
and
Cellulomonadaceae
(
Actinobacteria
) increased under oxic conditions. In contrast, the RNA contents of
Clostridiaceae
(cluster I,
Firmicutes
) and two uncultured family-level-taxa, i.e., “Cellu” and “Sphingo” (both
Bacteroidetes
) increased under anoxic conditions. That the degradation of cellobiose was independent of the availability of O
2
and that redox potentials decreased in response to anaerobic activities indicated that the degradation of cellobiose was linked to functionally redundant cellobiose-degrading taxa capable of altering redox conditions.
Possible Overestimation of Surface Disinfection Efficiency by Assessment Methods Based on Liquid Sampling Procedures as Demonstrated by
In Situ
Quantification of Spore Viability
Authors: Grand I. , Bellon-Fontaine M.-N. , Herry J.-M. , Hilaire D. , Moriconi F.-X. , Naïtali M.
Published: July 2011

The standard test methods used to assess the efficiency of a disinfectant applied to surfaces are often based on counting the microbial survivors sampled in a liquid, but total cell removal from surfaces is seldom achieved. One might therefore wonder whether evaluations of microbial survivors in liquid-sampled cells are representative of the levels of survivors in whole populations. The present study was thus designed to determine the “damaged/undamaged” status induced by a peracetic acid disinfection for
Bacillus atrophaeus
spores deposited on glass coupons directly on this substrate and to compare it to the status of spores collected in liquid by a sampling procedure. The method utilized to assess the viability of both surface-associated and liquid-sampled spores included fluorescence labeling with a combination of Syto 61 and Chemchrome V6 dyes and quantifications by analyzing the images acquired by confocal laser scanning microscopy. The principal result of the study was that the viability of spores sampled in the liquid was found to be poorer than that of surface-associated spores. For example, after 2 min of peracetic acid disinfection, less than 17% ± 5% of viable cells were detected among liquid-sampled cells compared to 79% ± 5% or 47% ± 4%, respectively, when the viability was evaluated on the surface after or without the sampling procedure. Moreover, assessments of the survivors collected in the liquid phase, evaluated using the microscopic method and standard plate counts, were well correlated. Evaluations based on the determination of survivors among the liquid-sampled cells can thus overestimate the efficiency of surface disinfection procedures.
Heavy-Machinery Traffic Impacts Methane Emissions as Well as Methanogen Abundance and Community Structure in Oxic Forest Soils
Authors: Frey Beat , Niklaus Pascal A. , Kremer Johann , Lüscher Peter , Zimmermann Stephan
Published: July 2011

Temperate forest soils are usually efficient sinks for the greenhouse gas methane, at least in the absence of significant amounts of methanogens. We demonstrate here that trafficking with heavy harvesting machines caused a large reduction in CH
4
consumption and even turned well-aerated forest soils into net methane sources. In addition to studying methane fluxes, we investigated the responses of methanogens after trafficking in two different forest sites. Trafficking generated wheel tracks with different impact (low, moderate, severe, and unaffected). We found that machine passes decreased the soils' macropore space and lowered hydraulic conductivities in wheel tracks. Severely compacted soils yielded high methanogenic abundance, as demonstrated by quantitative PCR analyses of methyl coenzyme M reductase (
mcrA
) genes, whereas these sequences were undetectable in unaffected soils. Even after a year after traffic compression, methanogen abundance in compacted soils did not decline, indicating a stability of methanogens here over time. Compacted wheel tracks exhibited a relatively constant community structure, since we found several persisting
mcrA
sequence types continuously present at all sampling times. Phylogenetic analysis revealed a rather large methanogen diversity in the compacted soil, and most
mcrA
gene sequences were mostly similar to known sequences from wetlands. The majority of
mcrA
gene sequences belonged either to the order
Methanosarcinales
or
Methanomicrobiales
, whereas both sites were dominated by members of the families
Methanomicrobiaceae
Fencluster, with similar sequences obtained from peatland environments. The results show that compacting wet forest soils by heavy machinery causes increases in methane production and release.
Biochemical Characterization and Relative Expression Levels of Multiple Carbohydrate Esterases of the Xylanolytic Rumen Bacterium Prevotella ruminicola 23 Grown on an Ester-Enriched Substrate
Authors: Kabel Mirjam A. , Yeoman Carl J. , Han Yejun , Dodd Dylan , Abbas Charles A. , de Bont Jan A. M. , Morrison Mark , Cann Isaac K. O. , Mackie Roderick I.
Published: July 2011

We measured expression and used biochemical characterization of multiple carbohydrate esterases by the xylanolytic rumen bacterium
Prevotella ruminicola
23 grown on an ester-enriched substrate to gain insight into the carbohydrate esterase activities of this hemicellulolytic rumen bacterium. The
P. ruminicola
23 genome contains 16 genes predicted to encode carbohydrate esterase activity, and based on microarray data, four of these were upregulated >2-fold at the transcriptional level during growth on an ester-enriched oligosaccharide (XOS
FA,Ac
) from corn relative to a nonesterified fraction of corn oligosaccharides (AXOS). Four of the 16 esterases (Xyn10D-Fae1A, Axe1-6A, AxeA1, and Axe7A), including the two most highly induced esterases (Xyn10D-Fae1A and Axe1-6A), were heterologously expressed in
Escherichia coli
, purified, and biochemically characterized. All four enzymes showed the highest activity at physiologically relevant pH (6 to 7) and temperature (30 to 40°C) ranges. The
P. ruminicola
23 Xyn10D-Fae1A (a carbohydrate esterase [CE] family 1 enzyme) released ferulic acid from methylferulate, wheat bran, corn fiber, and XOS
FA,Ac
, a corn fiber-derived substrate enriched in
O
-acetyl and ferulic acid esters, but exhibited negligible activity on sugar acetates. As expected, the
P. ruminicola
Axe1-6A enzyme, which was predicted to possess two distinct esterase family domains (CE1 and CE6), released ferulic acid from the same substrates as Xyn10D-Fae1 and was also able to cleave
O
-acetyl ester bonds from various acetylated oligosaccharides (AcXOS). The
P. ruminicola
23 AxeA1, which is not assigned to a CE family, and Axe7A (CE7) were found to be acetyl esterases that had activity toward a broad range of mostly nonpolymeric acetylated substrates along with AcXOS. All enzymes were inhibited by the proximal location of other side groups like 4-
O
-methylglucuronic acid, ferulic acid, or acetyl groups. The unique diversity of carbohydrate esterases in
P. ruminicola
23 likely gives it the ability to hydrolyze substituents on the xylan backbone and enhances its capacity to efficiently degrade hemicellulose.
L
-Arabitol Is the Actual Inducer of Xylanase Expression in Hypocrea jecorina (Trichoderma reesei)
Authors: Mach-Aigner Astrid R. , Gudynaite-Savitch Loreta , Mach Robert L.
Published: July 2011

The saprophytic fungus
Hypocrea jecorina
(anamorph,
Trichoderma reesei
) is an important native producer of hydrolytic enzymes, including xylanases. Regarding principles of sustainability, cheap and renewable raw materials, such as
d
-xylose (the backbone monomer of xylan), have been receiving increasing attention from industries. Recently, it was demonstrated that small (0.5 to 1 mM) amounts of
d
-xylose induce the highest expression of xylanase in
H. jecorina
. However, it was also reported that active metabolism of
d
-xylose is necessary for induction. In this report, we demonstrate that xylitol, the next intermediate in the pentose pathway after
d
-xylose, does not trigger transcription of xylanase-encoding genes in
H. jecorina
QM9414. The highest level of transcription of xylanolytic enzyme-encoding genes occurred in an
xdh1
(encoding a xylitol dehydrogenase) deletion strain cultured in the presence of 0.5 mM
d
-xylose, suggesting that a metabolite upstream of xylitol is the inducer. The expression levels of xylanases in an
xdh1
-
lad1
double-deletion strain were lower than that of an
xdh1
deletion strain. This observation suggested that
l
-xylulose is not an inducer and led to the hypothesis that
l
-arabitol is the actual inducer of xylanase expression. A direct comparison of transcript levels following the incubation of the
H. jecorina
parental strain with various metabolites of the pentose pathway confirmed this hypothesis. In addition, we demonstrate that
xyr1
, the activator gene, is not induced in the presence of pentose sugars and polyols, regardless of the concentration used; instead, we observed low constitutive expression of
xyr1
.
Anaerobic Oxidation of Benzene by the Hyperthermophilic Archaeon Ferroglobus placidus
Authors: Holmes Dawn E. , Risso Carla , Smith Jessica A. , Lovley Derek R.
Published: July 2011

Anaerobic benzene oxidation coupled to the reduction of Fe(III) was studied inFerroglobus placidusin order to learn more about how such a stable molecule could be metabolized under strict anaerobic conditions.F. placidusconserved energy to support growth at 85°C in a medium with benzene provided as the sole electron donor and Fe(III) as the sole electron acceptor. The stoichiometry of benzene loss and Fe(III) reduction, as well as the conversion of [14C]benzene to [14C]carbon dioxide, was consistent with complete oxidation of benzene to carbon dioxide with electron transfer to Fe(III). Benzoate, but not phenol or toluene, accumulated at low levels during benzene metabolism, and [14C]benzoate was produced from [14C]benzene. Analysis of gene transcript levels revealed increased expression of genes encoding enzymes for anaerobic benzoate degradation during growth on benzene versus growth on acetate, but genes involved in phenol degradation were not upregulated during growth on benzene. A gene for a putative carboxylase that was more highly expressed in benzene- than in benzoate-grown cells was identified. These results suggest that benzene is carboxylated to benzoate and that phenol is not an important intermediate in the benzene metabolism ofF. placidus. This is the first demonstration of a microorganism in pure culture that can grow on benzene under strict anaerobic conditions and for which there is strong evidence for degradation of benzene via clearly defined anaerobic metabolic pathways. Thus,F. placidusprovides a much-needed pure culture model for further studies on the anaerobic activation of benzene in microorganisms.
Different Roles of Membrane Potentials in Electrotaxis and Chemotaxis of Dictyostelium Cells
Authors: Gao Run-chi , Zhang Xiao-dong , Sun Yao-hui , Kamimura Yoichiro , Mogilner Alex , Devreotes Peter N. , Zhao Min
Published: July 2011

Many types of cells migrate directionally in direct current (DC) electric fields (EFs), a phenomenon termed galvanotaxis or electrotaxis. The directional sensing mechanisms responsible for this response to EFs, however, remain unknown. Exposing cells to an EF causes changes in plasma membrane potentials (
V

m

). Exploiting the ability of
Dictyostelium
cells to tolerate drastic
V

m

changes, we investigated the role of
V

m

in electrotaxis and, in parallel, in chemotaxis. We used three independent factors to control
V

m

: extracellular pH, extracellular [K
+
], and electroporation. Changes in
V

m

were monitored with microelectrode recording techniques. Depolarized
V

m

was observed under acidic (pH 5.0) and alkaline (pH 9.0) conditions as well as under higher extracellular [K
+
] conditions. Electroporation permeabilized the cell membrane and significantly reduced the
V

m

, which gradually recovered over 40 min. We then recorded the electrotactic behaviors of
Dictyostelium
cells with a defined
V

m

using these three techniques. The directionality (directedness of electrotaxis) was quantified and compared to that of chemotaxis (chemotactic index). We found that a reduced
V

m

significantly impaired electrotaxis without significantly affecting random motility or chemotaxis. We conclude that extracellular pH, [K
+
], and electroporation all significantly affected electrotaxis, which appeared to be mediated by the changes in
V

m

. The initial directional sensing mechanisms for electrotaxis therefore differ from those of chemotaxis and may be mediated by changes in resting
V

m

.
Contributions of Five Secondary Metal Uptake Systems to Metal Homeostasis of Cupriavidus metallidurans CH34
Authors: Kirsten Andreas , Herzberg Martin , Voigt Alexander , Seravalli Javier , Grass Gregor , Scherer Judith , Nies Dietrich H.
Published: July 2011

Cupriavidus metallidurans
is adapted to high concentrations of transition metal cations and is a model system for studying metal homeostasis in difficult environments. The elemental composition of
C. metallidurans
cells cultivated under various conditions was determined, revealing the ability of the bacterium to shield homeostasis of one essential metal from the toxic action of another. The contribution of metal uptake systems to this ability was studied.
C. metallidurans
contains three CorA members of the metal inorganic transport (MIT) protein family of putative magnesium uptake systems, ZupT of the ZRT/IRT protein, or ZIP, family, and PitA, which imports metal phosphate complexes. Expression of the genes for all these transporters was regulated by zinc availability, as shown by reporter gene fusions. While expression of
zupT
was upregulated under conditions of zinc starvation, expression of the other genes was downregulated at high zinc concentrations. Only
corA
1
expression was influenced by magnesium starvation. Deletion mutants were constructed to characterize the contribution of each system to transition metal import. This identified ZupT as the main zinc uptake system under conditions of low zinc availability, CorA
1
as the main secondary magnesium uptake system, and CorA
2
and CorA
3
as backup systems for metal cation import. PitA may function as a cation-phosphate uptake system, the main supplier of divalent metal cations and phosphate in phosphate-rich environments. Thus, metal homeostasis in
C. metallidurans
is achieved by highly redundant metal uptake systems, which have only minimal cation selectivity and are in combination with efflux systems that “worry later” about surplus cations.
Genome Sequence of Mycoplasma ovipneumoniae Strain SC01
Authors: Yang Falong , Tang Cheng , Wang Yong , Zhang Huanrong , Yue Hua
Published: July 2011

Mycoplasma ovipneumoniae
is associated with chronic nonprogressive pneumonia in both sheep and goats. Studies concerning its molecular pathogenesis, genetic analysis, and vaccine development have been hindered due to limited genomic information. Here, we announce the first complete genome sequence of this organism.
Draft Genome Sequence of the Polycyclic Aromatic Hydrocarbon-Degrading, Genetically Engineered Bioluminescent Bioreporter Pseudomonas fluorescens HK44
Authors: Chauhan Archana , Layton Alice C. , Williams Daniel E. , Smartt Abby E. , Ripp Steven , Karpinets Tatiana V. , Brown Steven D. , Sayler Gary S.
Published: July 2011

Pseudomonas fluorescens
strain HK44 (DSM 6700) is a genetically engineered
lux
-based bioluminescent bioreporter. Here we report the draft genome sequence of strain HK44. Annotation of ∼6.1 Mb of sequence indicates that 30% of the traits are unique and distributed over five genomic islands, a prophage, and two plasmids.
Genome Sequence of a Porcine Extraintestinal Pathogenic Escherichia coli Strain
Authors: Tan Chen , Xu Zhuofei , Zheng Huajun , Liu Wugang , Tang Xibiao , Shou Jin , Wu Bin , Wang Shengyue , Zhao Guo-Ping , Chen Huanchun
Published: July 2011

Extraintestinal pathogenic
Escherichia coli
(ExPEC) is an important pathogen which can infect humans and animals and cause many diseases outside the intestine. Here, we report the first draft genome sequence of a porcine ExPEC strain, PCN033, isolated from a pig with meningitis.
Genome Sequence of Ruegeria sp. Strain KLH11, anN-Acylhomoserine Lactone-Producing Bacterium Isolated from the Marine Sponge Mycale laxissima
Authors: Zan Jindong , Fricke W. Florian , Fuqua Clay , Ravel Jacques , Hill Russell T.
Published: July 2011

Ruegeriasp. strain KLH11, isolated from the marine spongeMycale laxissima, produces a complex profile ofN-acylhomoserine lactone quorum-sensing (QS) molecules. The genome sequence provides insights into the genetic potential of KLH11 to maintain complex QS systems, and this is the first genome report of a cultivated symbiont from a marine sponge.
Genome Sequence of the Rice-Pathogenic Bacterium Acidovorax avenae subsp. avenae RS-1
Authors: Xie Guan-Lin , Zhang Guo-Qing , Liu He , Lou Miao-Miao , Tian Wen-Xiao , Li Bin , Zhou Xue-Ping , Zhu Bo , Jin Gu-Lei
Published: July 2011

Acidovorax avenae
subsp.
avenae
is a phytobacterium which is the causative agent of several plant diseases with economic significance. Here, we present the draft genome sequence of strain RS-1, which was isolated from rice shoots in a rice field in China. This strain can cause bacterial stripe of rice.
Complete Genome Sequence of Clostridium acetobutylicum DSM 1731, a Solvent-Producing Strain with Multireplicon Genome Architecture
Authors: Bao Guanhui , Wang Runjiang , Zhu Yan , Dong Hongjun , Mao Shaoming , Zhang Yanping , Chen Zugen , Li Yin , Ma Yanhe
Published: July 2011

Clostridium acetobutylicum
is an important microorganism for solvent production. We report the complete genome sequence of
C. acetobutylicum
DSM 1731, a genome with multireplicon architecture. Comparison with the sequenced type strain
C. acetobutylicum
ATCC 824, the genome of strain DSM1731 harbors a 1.7-kb insertion and a novel 11.1-kb plasmid, which might have been acquired during evolution.
Genome Sequence of Lactobacillus ruminis SPM0211, Isolated from a Fecal Sample from a Healthy Korean
Authors: Lee Sunghee , Cho Yong-Joon , Lee Anne Hayoung , Chun Jongsik , Ha Nam-Joo , Ko GwangPyo
Published: July 2011

Lactobacillus ruminis
SPM0211 is a potential probiotic strain that shows antimicrobial activity against emerging pathogens. Here we present the draft genomic sequence of
L. ruminis
SPM0211, isolated from a fecal sample from a healthy Korean and describe both the common and unique features of this strain.
Complete Genome Sequences of the Chemolithoautotrophic Oligotropha carboxidovorans Strains OM4 and OM5
Authors: Volland Sonja , Rachinger Michael , Strittmatter Axel , Daniel Rolf , Gottschalk Gerhard , Meyer Ortwin
Published: July 2011

We report on genome sequencing of
Oligotropha carboxidovorans
strain OM4 and resequencing of strain OM5. The genomes of both are composed of one chromosome and two plasmids. The presence of two plasmids in the OM5 genome is inconsistent with the previously published sequence, for which only one plasmid was described (D. Paul, S. Bridges, S. Burgess, Y. Dandass, and M. Lawrence, BMC Genomics 11:511, 2010).
Complete Genome Sequence of Bifidobacterium longum subsp. longum KACC 91563
Authors: Ham Jun-Sang , Lee Taeheon , Byun Mi-Jeong , Lee Kyung-Tae , Kim Min-Kyung , Han Gi-Sung , Jeong Seok-Geun , Oh Mi-Hwa , Kim Dong-Hun , Kim Heebal
Published: July 2011

Bifidobacterium longum
strains predominate in the colonic microbiota of breast-fed infants. Here we report the complete genome sequence of
B. longum
subsp.
longum
KACC 91563, isolated from feces of neonates. A single circular chromosome of 2,385,301 bp contains 1,980 protein-coding genes, 56 tRNA genes, and 3 rRNA operons.
Genome Sequence of Lactobacillus johnsonii PF01, Isolated from Piglet Feces
Authors: Lee Je Hee , Chae Jong Pyo , Lee Ji Yoon , Lim Jong-Sung , Kim Geun-Bae , Ham Jun-Sang , Chun Jongsik , Kang Dae-Kyung
Published: July 2011

Lactobacillus johnsonii
PF01, an autochthonous bacterium of the gastrointestinal tract, was isolated from a fecal sample from a piglet. The strain adhered specifically to the duodenal and jejunal epithelial cells of the piglet and had high bile resistance activity. Here we report the genomic sequence of
L. johnsonii
PF01.
Spontaneous anterior dislocation of a mature cataract following old trauma: Figure 1
Authors: Bansal Shveta , Taherian Kasra
Published: July 2011

We report a case of a patient who incurred spontaneous anterior dislocation of a mature cataract which required prompt surgical removal. Some years previous to this, he had sustained blunt trauma to the eye.
Expression of phosphoinositide-specific phospholipase C isoforms in human umbilical vein endothelial cells
Authors: Lo Vasco V R , Pacini L , Di Raimo T , D'arcangelo D , Businaro R
Published: July 2011

Aims

The signalling system of phosphoinositides (PIs) is involved in a number of cell and tissue functions including membrane trafficking, ion channel activity, cell cycle, apoptosis, differentiation and cell and tissue polarity. Recently, a role in cell migration was hypothesised for PI and related molecules including the phosphoinositide-specific phospholipases C (PI-PLCs), main players in PI signalling. The expression of PI-PLCs is tissue-specific and evidence suggests that it varies under different conditions such as tumour progression or cell activation. In order to obtain a complete picture, the expression of all PI-PLC isoforms was analysed in human endothelial cells (EC).

Methods

Using molecular biology methods (RT-PCR), the expression of PI-PLC isoforms was analysed in human umbilical vein endothelial cells (HUVEC), a widely used experimental model for human EC.

Results

All the PI-PLC isoforms except PI-PLC β1, PI-PLC ɛ and PI-PLC ζ were expressed in HUVEC.

Conclusions

The growing interest in the complex cascade of events occurring in angiogenesis will provide useful insights for therapeutic strategies. The expression of PI-PLC isoforms in HUVEC is a useful tool for further studies directed to understanding their role in angiogenesis. However, although HUVEC represent a widely used experimental model for human macrovascular EC, limitations remain in that they cannot fully represent the metabolic properties and interactions of the EC distributed in the entire organism.
Exposure–response relationship between chrysotile exposure and mortality from lung cancer and asbestosis
Authors: Deng Qian , Wang Xiaorong , Wang Mianzheng , Lan Yajia
Published: July 2011

Objectives

To describe mortality in workers exposed to chrysotile asbestos, and determine exposure–response relationships between asbestos exposure and mortality from lung cancer and asbestosis by fitting and comparing different models.

Methods

A prospective cohort consisting of 586 workers in an asbestos textile factory was followed from 1 January 1972 to 31 December 2006. A structured questionnaire was administered to collect personal information and exposure data. Paired concentration samples measured in the workshops were used to convert dust concentrations to fibre concentrations. Individual cumulative asbestos exposure was estimated as the product of fibre concentrations and duration of employment in each job and expressed as fibre-years/ml. The vital status of cohort members was followed annually. Poisson regression analysis was applied to fit log-linear, log-quadratic, power, additive relative risk and categorical models to estimate exposure–response relationships between cumulative fibre exposure and mortality from lung cancer and asbestosis.

Results

Of the 226 deaths (14.6 per 1000 person-years) over the 35-year follow-up, 51 were from lung cancer (3.29 per 1000 person-years) and 37 from asbestosis (2.39 per 1000 person-years). A significant exposure–response relationships with either lung cancer or asbestosis (p<0.001) was observed in the final model. The power model with lagged 10 years was found to be the best model of those evaluated for both lung cancer (β coefficient=0.53) and asbestosis (β coefficient=0.63).

Conclusions

The study confirmed strong associations between exposure to chrysotile asbestos and lung cancer and asbestosis, in which clear exposure–response relationships were observed.
Arteriolar reactivity in lymphocyte-deficient mice
Authors: Leonard Sean , Croy B. Anne , Murrant Coral L.
Published: July 2011

Mounting evidence suggests that lymphocytes have the capacity to contribute to the regulation of systemic circulatory control. We postulated that T and natural killer (NK) cells could modify basal microvascular activity under physiologically normal conditions. In situ intravital microscopy of mouse cremaster vasculature was used to evaluate arteriolar reactivities to the vasoconstrictors angiotensin II (ANG II) and phenylephrine (Phe) and the vasodilators acetylcholine (ACh) and adenosine (Ado) in normal [+/+; wild type (WT)] and genetically immunodeficient (T−B−NK+or T−B−\NK−) C57BL/6 and BALB/c mice, strain backgrounds with differentially polarized T cell cytokine production. Immunodeficient mice tended to have smaller baseline and maximal diameters of third-order cremaster arterioles than their congenic WT partners. In C57BL/6, baseline diameters were similar in T-B−mice without or with NK cells; in BALB/c, baseline diameters were larger in T-B-NK−mice than in T−B−NK+mice. Thus, at baseline, lymphocytes tended to promote vasodilation, except BALB/c NK cells, which mediated mild vasoconstriction. The presence of NK cells suppressed dilations to Ado in both strains, to ACh in the C57BL/6 strain, and dilatory responses to ANG II in C57BL/6 and to Phe in BALB/c. In the BALB/c strain, the presence of T and B cells promoted vasodilatory responses to Ado, attenuated dilations to low ACh concentrations, and exaggerated dilation and constriction responses to ANG II. Thus, under agonist challenge, NK cells generally promote constriction, whereas influences of T and B cells depend upon the stimulus. Therefore, lymphocytes or their products have physiological influences on microvascular arteriolar reactivity.
Targeting intracellular calcium cycling in catecholaminergic polymorphic ventricular tachycardia: a theoretical investigation
Authors: Sung Ruey J. , Lo Chu-Pin , Hsiao Pi Yin , Tien Hui-Chun
Published: July 2011

Catecholaminergic polymorphic ventricular tachycardia (CPVT) is a malignant arrhythmogenic disorder linked to mutations in the cardiac ryanodine receptor (RyR2) and calsequestrin, predisposing the young to syncope and cardiac arrest. To define the role of β-adrenergic stimulation (BAS) and to identify potential therapeutic targeted sites relating to intracellular calcium cycling, we used a Luo-Rudy dynamic ventricular myocyte model incorporated with interacting Markov models of the L-type Ca2+ channel ( ICa,L) and RyR2 to simulate the heterozygous state of mouse RyR2 R4496C mutation (RyR2R4496C+/−) comparable with CPVT patients with RyR2 R4497C mutation. Characteristically, in simulated cells, pacing at 4 Hz or faster or pacing at 2 Hz under BAS with effects equivalent to those of isoproterenol at ≥0.1 μM could readily induce delayed afterdepolarizations (DADs) and DAD-mediated triggered activity (TA) in RyR2R4496C+/− but not in the wild-type via enhancing both ICa,L and sarcoplasmic reticulum (SR) Ca2+ ATPase ( IUP). Moreover, with the use of steady state values of isolated endocardial (Endo), mid-myocardial (M), and epicardial (Epi) cells as initial data for conducting single cell and one-dimensional strand studies, the M cell was more vulnerable for developing DADs and DAD-mediated TA than Endo and Epi cells, and the gap junction coupling represented by diffusion coefficient ( D) of ≤0.000766*98 cm2/ms was required for generating DAD-mediated TA in RyR2R4496C+/−. Whereas individual reduction of Ca2+ release channel of SR and Na-Ca exchanger up to 50% was ineffective, 30% or more reduction of either ICa,L or IUP could totally suppress the inducibility of arrhythmia under BAS. Of note, 15% reduction of both ICa,L and IUP exerted a synergistic antiarrhythmic efficacy. Findings of this model study confirm that BAS facilitates induction of ventricular tachyarrhythmias via its action on intracellular Ca2+ cycling and a pharmacological regimen capable of reducing ICa,L could be an effective adjunctive to β-adrenergic blockers for suppressing ventricular tachyarrhythmias during CPVT.
Differential flux of macrophage inflammatory protein-2 and cytokine-induced neutrophil chemoattractant from the lung after intrapulmonary delivery
Authors: Zamjahn John B. , Quinton Lee J. , Mack Justin C. , Frevert Charles W. , Nelson Steve , Bagby Gregory J.
Published: July 2011

Previously we showed that cytokine-induced neutrophil chemoattractant (CINC), but not macrophage inflammatory protein-2 (MIP-2), is detected in plasma after intratracheal challenge with LPS or the particular chemokines. To further understand the differences between CINC and MIP-2 flux from the lung, we attempted to detect the two chemokines in isolated erythrocytes and leukocytes in rats after intratracheal LPS challenge. In response to intratracheal LPS, we found both CINC and MIP-2 in isolated erythrocytes and leukocytes, suggesting that MIP-2 produced in the LPS-challenged lung entered the circulation like CINC. To assess the relative flux of CINC and MIP-2 from the intra-alveolar compartment into the blood, experiments were performed in rats implanted with vascular catheters in which both chemokines were either injected intratracheally (5 μg) or infused intravenously (20 ng/min) and subsequently measured in plasma or with the cellular elements. Both chemokines appeared in the blood following intratracheal injection, with CINC detected in plasma and cells but MIP-2 only detected in the cellular fraction of blood. Infusion of both chemokines allowed detection of MIP-2 and CINC in plasma and with the cellular elements, which allowed us to calculate clearance for each chemokine and to assess CINC and MIP-2 rates of appearance (Ra) following intratracheal injection. On the basis of plasma and whole blood clearance, CINC Ra was more than sevenfold and fourfold higher, respectively, than MIP-2 Ra. This analysis indicates that differences exist in the rate of flux of CINC and MIP-2 across the epithelial/endothelial barrier of the lung, despite similar molecular size.
Cigarette smoke exposure aggravates air space enlargement and alveolar cell apoptosis inSmad3knockout mice
Authors: Farkas Laszlo , Farkas Daniela , Warburton David , Gauldie Jack , Shi Wei , Stampfli Martin R. , Voelkel Norbert F. , Kolb Martin
Published: July 2011

The concept of genetic susceptibility factors predisposing cigarette smokers to develop emphysema stems from the clinical observation that only a fraction of smokers develop clinically significant chronic obstructive pulmonary disease. We investigated whether Smad3 knockout mice, which develop spontaneous air space enlargement after birth because of a defect in transforming growth factor-β (TGF-β) signaling, develop enhanced alveolar cell apoptosis and air space enlargement following cigarette smoke exposure. We investigated Smad3−/−and Smad3+/+mice at different adult ages and determined air space enlargement, alveolar cell proliferation, and apoptosis. Furthermore, laser-capture microdissection and real-time PCR were used to measure compartment-specific gene expression. We then compared the effects of cigarette smoke exposure on Smad3−/−and littermate controls. Smad3 knockout resulted in the development of air space enlargement in the adult mouse and was associated with decreased alveolar VEGF levels and activity and increased alveolar cell apoptosis. Cigarette smoke exposure aggravated air space enlargement and alveolar cell apoptosis. We also found increased Smad2 protein expression and phosphorylation, which was enhanced following cigarette smoke exposure, in Smad3-knockout animals. Double immunofluorescence analysis revealed that endothelial apoptosis started before epithelial apoptosis. Our data indicate that balanced TGF-β signaling is not only important for regulation of extracellular matrix turnover, but also for alveolar cell homeostasis. Impaired signaling via the Smad3 pathway results in alveolar cell apoptosis and alveolar destruction, likely via increased Smad2 and reduced VEGF expression and might represent a predisposition for accelerated development of emphysema due to cigarette smoke exposure.
Expectations of Care, Perceived Safety, and Anxiety following Acute Behavioural Disturbance in the Emergency Department
Authors: Lim Magdalen , Weiland Tracey , Gerdtz Marie , Dent Andrew
Published: July 2011

Objective. We explored perspectives of emergency department users (patients and visitors) regarding the management of acute behavioural disturbances in the emergency department and whether these disturbances influenced their levels of anxiety.Methods. Emergency department patients and visitors were surveyed using the State-Trait Anxiety Inventory, and a purpose-designed questionnaire and semistructured interview. The main outcome measures were themes that emerged from the questionnaires, the interviews, and scores from the state component of the State-Trait Anxiety Inventory.Results. 70 participants were recruited. Users of the emergency department preferred behaviourally disturbed people be managed in a separate area from the general emergency department population so that the disturbance was inaudible () and out of view (). The state anxiety levels of those that witnessed an acute behavioural disturbance were within the normal range and did not differ to that of ED patients that were not present during such a disturbance (median, control = 37, Code Grey = 33).Conclusions. Behavioural disturbances in the emergency department do not provoke anxiety in other users. However, there is a preference that such disturbances be managed out of visual and audible range. Innovative design features may be required to achieve this.
Persistent Ureteric Dilatation due to Pelvic Actinomycosis Presenting as Pelvic Inflammatory Disease
Authors: Khafagy Richard , Jundi Omar , Rogawski Karol , Namasiviyam Siva
Published: July 2011

Actinomycesis a Gram-positive, filamentous bacterium that normally colonizes mucosal areas. Pelvic actinomycosis is a chronic granulomatous disease caused byActinomyces israeliithat frequently mimics ovarian tumors during presentation. It is diagnosed after surgery in most of the cases. Intravenous penicillin is the most preferred therapeutic agent, and it requires hospitalization up to one month. Pelvic actinomycosis is a rare cause of ureteric obstruction and renal failure. The final diagnosis is usually difficult and often apparent only after histological examination of an operative specimen. The present case led us to consider the etiology and clinical findings and to review the management of reported cases involving ureteric obstruction.
Modeling Reader's Emotional State Response on Document's Typographic Elements
Authors: Tsonos Dimitrios , Kouroupetroglou Georgios
Published: July 2011

We present the results of an experimental study towards modeling the reader's emotional state variations induced by the typographic elements in electronic documents. Based on the dimensional theory of emotions we investigate how typographic elements, like font style (bold, italics, bold-italics) and font (type, size, color and background color), affect the reader's emotional states, namely, Pleasure, Arousal, and Dominance (PAD). An experimental procedure was implemented conforming to International Affective Picture System guidelines and incorporating the Self-Assessment Manikin test. Thirty students participated in the experiment. The stimulus was a short paragraph of text for which any content, emotion, and/or domain dependent information was excluded. The Analysis of Variance revealed the dependency of (a) all the three emotional dimensions on font size and font/background color combinations and (b) the Pleasure dimension on font type and font style. We introduce a set of mapping rules showing how PAD vary on the discrete values of font style and font type elements. Moreover, we introduce a set of equations describing the PAD dimensions' dependency on font size. This novel model can contribute to the automated reader's emotional state extraction in order, for example, to enhance the acoustic rendition of the documents, utilizing text-to-speech synthesis.
Hepatitis B Reactivation in a HBsAg-Negative, HBcAb-Positive Patient Receiving Fludarabine for the Treatment of Chronic Lymphocytic Leukaemia
Authors: Toscanini Federica , De Leo Pasqualina , Calcagno Giuseppe , Malfatti Federica , Grasso Alessandro , Anselmo Marco
Published: July 2011

Hepatitis B virus (HBV) reactivation is an increasingly recognized cause of morbidity and mortality in patients undergoing chemotherapy. In haematology, the risk of reactivation of B hepatitis among HBsAg-positive patients has been documented; therefore, use of lamivudine prophylaxis is recommended before starting chemotherapy. Differently, for HBsAg-negative patients with markers of previous HBV infection (i.e., presence of isolated anti-HBc positivity) (anticore patients) management strategies are not univocal. We describe a rare case of HBV reactivation in an anticore patient after fludarabine therapy for chronic lymphocytic leukaemia. The patient fully recovered after a 6-month course of lamivudine with persistent HBV-DNA clearance and loss of HBsAg. The most important feature of this case is that fludarabine alone infrequently determines HBV reactivation, especially in anticore patients. Therefore, we suggest that patients candidates to receive fludarabine therapy should be considered for lamivudine prophylaxis, not only if HBsAg-positive, but even if anticore-positive only.
A Graphical Method for Solving Interval Matrix Games
Authors: Akyar Handan , Akyar Emrah
Published: July 2011

2 × n or m × 2 interval matrix games are considered, and a graphical
method for solving such games is given. Interval matrix game is
the interval generation of classical matrix games. Because of
uncertainty in real‐world applications, payoffs of a matrix
game may not be a fixed number. Since the payoffs may vary within
a range for fixed strategies, an interval‐valued matrix can
be used to model such uncertainties. In the literature, there are
different approaches for the comparison of fuzzy numbers and
interval numbers. In this work, the idea of acceptability index is
used which is suggested by Sengupta et al. (2001) and Sengupta and
Pal (2009), and in view of acceptability index, well‐known
graphical method for matrix games is adapted to interval matrix
games.
Fuzzy Portfolio Selection Problem with Different Borrowing and Lending Rates
Authors: Chen Wei , Yang Yiping , Ma Hui
Published: July 2011

As we know, borrowing and lending risk‐free assets arise extensively in the theory and practice of finance. However, little study has ever investigated them in fuzzy portfolio problem. In this paper,
the returns of each assets are assumed to be fuzzy variables, then following the mean‐variance approach, a new possibilistic portfolio selection model with different interest rates for borrowing and lending is proposed, in which the possibilistic semiabsolute deviation of the return is used to measure investment risk. The conventional probabilistic mean variance model can be transformed to a linear programming problem under possibility distributions. Finally, a numerical example is given to illustrate the modeling idea and the impact of borrowing and lending on optimal decision making.
Ureteral Strangulation by Fibrosis: A Cold Case Report of Ormand's Disease
Authors: Sandhu Amarpreet , Brickner Leslea , Chen Mark
Published: July 2011

Retroperitoneal fibrosis or Ormand's disease is rare in incidence and clinically elusive to diagnosis until obstructive uropathy clinically manifests by the mechanism of ureteral fibrotic strangulation and acute renal failure. We encountered a 50-year-old woman with months of nonspecific abdominal pain and presented with signs and symptoms of acute renal failure. Laboratory data was significant for blood urea nitrogen 47 mg/dL and creatinine of 8.47 mg/dL. Renal ultrasound revealed bilateral hydronephrosis and an abdominal computed tomogram confirmed an abnormal soft tissue retroperitoneal confluence that encased the pelvic vessels. Urologic consultation was requested and bilateral ureteral stents were placed with relief of her obstructive uropathy. Five days after ureteral stenting her creatinine dropped to 1.64 mg/dL. One month later patient underwent ureterolysis with biopsy showing fibroblast proliferation consistent with acute and chronic inflammation. By ruling out infections and malignancy, the final diagnosis was made to be idiopathic retroperitoneal fibrosis.
Two Cases of Enlarged Zuckerkandl's Tubercle of the Thyroid Displacing the Recurrent Laryngeal Nerve Laterally
Authors: Gurleyik Emin
Published: July 2011

The thyroid has many anatomic variations. Zuckerkandl's tubercle (ZT) is the posterior extension of lateral lobes. ZT has a relation with the recurrent laryngeal nerve (RLN). RLN lateral to ZT is an uncommon occurrence. This paper presents two cases of this uncommon situation. A 60-year-old female patient with large multinodular goiter was treated with total thyroidectomy. A 69-year-old male patient with follicular neoplasm was treated with total lobectomy. The inferior thyroid arteries and the recurrent laryngeal nerves were identified with usual lateral approach. A left ZT was found in case 1 and a right ZT in case 2. Distal parts of the RLNs were displaced laterally by enlarged ZTs in both cases. Grade 3 ZTs composed of thyroid tissue were placed between the trachea and the RLNs. The ZT is a common anatomic feature of the thyroid. Close relation of the tubercle with the RLN is an important surgical entity. The enlarged ZT seldom pushes the nerve laterally. The knowledge of the anatomy of ZT and its relation with the RLN including all variations is mandatory for safe thyroid operations.
Corpus Callosum Microstructural Changes Correlate with Cognitive Dysfunction in Early Stages of Relapsing-Remitting Multiple Sclerosis: Axial and Radial Diffusivities Approach
Authors: Rimkus Carolina de Medeiros , Junqueira Thiago de Faria , Lyra Katarina Paz , Jackowski Marcel P. , Machado Melissa A. R. , Miotto Eliane C. , Callegaro Dagoberto , Otaduy Maria Concepción García , Leite Claudia da Costa
Published: July 2011

The corpus callosum is the largest fiber bundle in the central nervous system and it takes part in several cognitive pathways. It can be affected by multiple sclerosis (MS) early in the disease. DTI is capable of infering the microstructural organization of the white matter. The vectorial analysis of the DTI offers the more specific indices of axial diffusivity (AD) and radial diffusivity (RD), which have shown to be useful to discriminate myelin damage from axon loss, respectively. This study presents DTI results (mean diffusivity (MD), fractional anisotropy (FA), RD, and AD) of 23 relapsing-remitting MS patients and its correlation with cognitive performance. There were 47.8% of cognitive impaired patients (MS CI). We found signs of demyelination, reflected by increased RD, and incipient axon loss, reflected by AD increase, which was slightly higher in the MS CI. The cognitive changes correlated with the DTI parameters, suggesting that loss of complexity in CC connections can impair neural conduction. Thus, cognitive impairment can be related to callosal disconnection, and DTI can be a promising tool to evaluate those changes.
Hydrogen Adsorption on Palladium and Platinum Overlayers: DFT Study
Authors: Pašti Igor A. , Gavrilov Nemanja M. , Mentus Slavko V.
Published: July 2011

Hydrogen adsorption on twenty different palladium and platinum overlayer surfaces with (111) crystallographic orientation was studied by means of periodic DFT calculations on the GGA‐PBE level. Palladium and platinum overlayers here denote either the Pd and Pt mono‐ and bilayers deposited over (111) crystallographic plane of Pd, Pt, Cu, and Au monocrystals or the (111) crystallographic plane of Pd and Pt monocrystals with inserted one‐atom‐thick surface underlayer of Pd, Pt, Cu, and Au. The attention was focused on the bond lengths, hydrogen adsorption energetics, mobility of adsorbed hydrogen, and surface reactivity toward hydrogen electrode reactions. Both the ligand and strain effects were considered, found to lead to a significant modification of the electronic structure of Pd and Pt overlayers, described through the position of the d‐band center, and tuning of the hydrogen adsorption energy in the range that covers approximately 120 kJmol−1. Mobility of hydrogen adsorbed on studied overlayers was found to be determined by hydrogen‐metal binding energy. Obtained results regarding Pd layers on Pt(111) and Au(111) surfaces, in conjunction with some of the recent experimental data, were used to explain its electrocatalytic activity towards hydrogen evolution reaction.
Malignant Range Elevation of Serum Chromogranin A due to Inadvertent Use of Proton Pump Inhibitor in a Subject with Pancreatic Incidentaloma
Authors: Malabu Usman Hammawa , Karamatic Rozemary , Mahy Gillian , Sangla Kunwarjit Singh
Published: July 2011

We present a case of highly elevated tenfold rise of serum chromogranin A in a young, morbidly obese, hypertensive female being investigated for pancreatic mass, weight loss, and elevated ESR. Following extensive noninvasive investigations, an ultrasound-guided pancreatic biopsy confirmed benign haemorrhagic cyst. A clue to the etiology of the hyperchromogranin A was the elevated serum gastrin level leading to suspicion of proton pump inhibitor administration confirmed by admittance to its use. Withdrawal of the medication led to dramatic resolution of the neuroendocrine tumor marker.
Secondary Flow Loss Reduction in a Turbine Cascade with a Linearly Varied Height Streamwise Endwall Fence
Authors: Kumar Krishna Nandan , Govardhan M.
Published: July 2011

The present study attempts to reduce secondary flow losses by application of streamwise endwall fence. After comprehensive analysis on selection of objective function for secondary flow loss reduction, coefficient of secondary kinetic energy (CSKE) is selected as the objective function in this study. A fence whose height varies linearly from the leading edge to the trailing edge and located in the middle of the flow passage produces least CSKE and is the optimum fence. The reduction in CSKE by the optimum fence is 27% compared to the baseline case. The geometry of the fence is new and is reported for the first time. Idea of this fence comes from the fact that the size of the passage vortex (which is the prime component of secondary flow) increases as it travels downstream, hence the height of fence should vary as the objective of fence is to block the passage vortex from crossing the passage and impinging on suction surface of the blade. Optimum fence reduced overturning and underturning of flow by more than 50% compared to the baseline case. Magnitude and spanwise penetration of the passage vortex were reduced considerably compared to the baseline case.