bluuebunny/crossref_metadata_2025 huggingface dataset:
Cooccurring
Gentiana verna
and
Gentiana acaulis
and Their Neighboring Plants in Two Swiss Upper Montane Meadows Harbor Distinct Arbuscular Mycorrhizal Fungal Communities
Authors: Sýkorová Zuzana , Wiemken Andres , Redecker Dirk
Published: July 2007

The community composition of arbuscular mycorrhizal fungi (AMF) was analyzed in roots of
Gentiana verna
,
Gentiana acaulis
, and accompanying plant species from two species-rich Swiss alpine meadows located in the same area. The aim of the study was to elucidate the impact of host preference or host specificity on the AMF community in the roots. The roots were analyzed by nested PCR, restriction fragment length polymorphism screening, and sequencing of ribosomal DNA small-subunit and internal transcribed spacer regions. The AMF sequences were analyzed phylogenetically and used to define monophyletic sequence types. The AMF community composition was strongly influenced by the host plant species, but compositions did not significantly differ between the two sites. Detailed analyses of the two cooccurring gentian species
G. verna
and
G. acaulis
, as well as of neighboring
Trifolium
spp., revealed that their AMF communities differed significantly. All three host plant taxa harbored AMF communities comprising multiple phylotypes from different fungal lineages. A frequent fungal phylotype from
Glomus
group B was almost exclusively found in
Trifolium
spp., suggesting some degree of host preference for this fungus in this habitat. In conclusion, the results indicate that within a relatively small area with similar soil and climatic conditions, the host plant species can have a major influence on the AMF communities within the roots. No evidence was found for a narrowing of the mycosymbiont spectrum in the two green gentians, in contrast to previous findings with their achlorophyllous relatives.
Metabolic Engineering of
Saccharomyces cerevisiae
for Conversion of
d
-Glucose to Xylitol and Other Five-Carbon Sugars and Sugar Alcohols
Authors: Toivari Mervi H. , Ruohonen Laura , Miasnikov Andrei N. , Richard Peter , Penttilä Merja
Published: July 2007

Recombinant
Saccharomyces cerevisiae
strains that produce the sugar alcohols xylitol and ribitol and the pentose sugar
d
-ribose from
d
-glucose in a single fermentation step are described. A transketolase-deficient
S. cerevisiae
strain accumulated
d
-xylulose 5-phosphate intracellularly and released ribitol and pentose sugars (
d
-ribose,
d
-ribulose, and
d
-xylulose) into the growth medium. Expression of the xylitol dehydrogenase-encoding gene
XYL2
of
Pichia stipitis
in the transketolase-deficient strain resulted in an 8.5-fold enhancement of the total amount of the excreted sugar alcohols ribitol and xylitol. The additional introduction of the 2-deoxy-glucose 6-phosphate phosphatase-encoding gene
DOG1
into the transketolase-deficient strain expressing the
XYL2
gene resulted in a further 1.6-fold increase in ribitol production. Finally, deletion of the endogenous xylulokinase-encoding gene
XKS1
was necessary to increase the amount of xylitol to 50% of the 5-carbon sugar alcohols excreted.
Role of
laeA
in the Regulation of
alb1
,
gliP
, Conidial Morphology, and Virulence in
Aspergillus fumigatus
Authors: Sugui Janyce A. , Pardo Julian , Chang Yun C. , Müllbacher Arno , Zarember Kol A. , Galvez Eva M. , Brinster Lauren , Zerfas Patricia , Gallin John I. , Simon Markus M. , Kwon-Chung Kyung J.
Published: July 2007

The
alb1
(
pksP
) gene has been reported as a virulence factor controlling the pigmentation and morphology of conidia in
Aspergillus fumigatus
. A recent report suggested that
laeA
regulates
alb1
expression and conidial morphology but not pigmentation in the
A. fumigatus
strain AF293.
laeA
has also been reported to regulate the synthesis of secondary metabolites, such as gliotoxin. We compared the role of
laeA
in the regulation of conidial morphology and the expression of
alb1
and
gliP
in strains B-5233 and AF293, which differ in colony morphology and nutritional requirements. Deletion of
laeA
did not affect conidial morphology or pigmentation in these strains, suggesting that
laeA
is not involved in
alb1
regulation during conidial morphogenesis. Deletion of
laeA
, however, caused down-regulation of
alb1
during mycelial growth in a liquid medium. Transcription of
gliP
, involved in the synthesis of gliotoxin, was drastically reduced in B-5233
laeAΔ
, and the gliotoxin level found in the culture filtrates was 20% of wild-type concentrations. While up-regulation of
gliP
in AF293 was comparable to that in B-5233, the relative mRNA level in AF293
laeAΔ
was about fourfold lower than that in B-5233
laeAΔ
. Strain B-5233
laeAΔ
caused slower onset of fatal infection in mice relative to that with B-5233. Histopathology of sections from lungs of infected mice corroborated the survival data. Culture filtrates from B-5233
laeAΔ
caused reduced death in thymoma cells and were less inhibitory to a respiratory burst of neutrophils than culture filtrates from B-5233. Our results suggest that while
laeA
is not involved in the regulation of
alb1
function in conidial morphology, it regulates the synthesis of gliotoxin and the virulence of
A. fumigatus.
EhLimA, a Novel LIM Protein, Localizes to the Plasma Membrane inEntamoeba histolytica
Authors: Wender Nomy , Villalobo Eduardo , Mirelman David
Published: July 2007

The parasitic protozoanEntamoeba histolyticarelies on a very dynamic cytoskeleton in order to invade and survive in host tissues. Identification of cytoskeletal elements is key to understanding these processes. Here we present the characterization of EhLimA, the first LIM protein ofE. histolytica. EhLimA consists of a single LIM domain at its N terminus and exhibits the highest degree of homology with DdLimE fromDictyostelium discoideum. Immunofluorescence localization of EhLimA using anti-EhLimA antibodies revealed that EhLimA is highly concentrated at the plasma membrane of cells. Silencing or overexpression of the EhLimAgene did not have a significant effect on the growth or morphology of the parasite. EhLimA associates with the cytoskeleton as demonstrated by the enrichment of the protein in cytoskeleton fractions as well as in pull-down assays that revealed that cytoskeleton association involves interaction with actin. EhLimA binding to actin was shown to be dependent on the N-terminal LIM domain of EhLimA, as removal of even half of the LIM domain resulted in almost complete inhibition of the binding to actin. We also found that a portion of EhLimA floats to the lower-density regions of a sucrose gradient together with portions of the Gal-lectin light subunit and actin. Treatment of cells with the cholesterol-sequestering agent digitonin resulted in increased solubility of EhLimA. These results indicate that in addition to cytoskeletal association, EhLimA may also associate with lipid rafts in the parasite plasma membrane and suggest that EhLimA may be part of the molecular system connecting the actin cytoskeleton to membrane rafts.
Aspergillus nidulans
Conidiation Genes
dewA
,
fluG
, and
stuA
Are Differentially Regulated in Early Vegetative Growth
Authors: Breakspear Andrew , Momany Michelle
Published: July 2007

Microarray analysis was used to identify transcriptional changes in early vegetative growth of the filamentous fungus
Aspergillus nidulans
. The results suggest that the previously identified conidiation genes
dewA
,
fluG
, and
stuA
may function in isotropic expansion during early vegetative growth and asexual reproduction.
VirB1* Promotes T-Pilus Formation in the
vir
-Type IV Secretion System of
Agrobacterium tumefaciens
Authors: Zupan John , Hackworth Cheryl A. , Aguilar Julieta , Ward Doyle , Zambryski Patricia
Published: July 2007

The
vir
-type IV secretion system of
Agrobacterium
is assembled from 12 proteins encoded by the
virB
operon and
virD4
. VirB1 is one of the least-studied proteins encoded by the
virB
operon. Its N terminus is a lytic transglycosylase. The C-terminal third of the protein, VirB1*, is cleaved from VirB1 and secreted to the outside of the bacterial cell, suggesting an additional function. We show that both nopaline and octopine strains produce abundant amounts of VirB1* and perform detailed studies on nopaline VirB1*. Both domains are required for wild-type virulence. We show here that the nopaline type VirB1* is essential for the formation of the T pilus, a subassembly of the
vir
-T4SS composed of processed and cyclized VirB2 (major subunit) and VirB5 (minor subunit). A nopaline
virB1
deletion strain does not produce T pili. Complementation with full-length VirB1 or C-terminal VirB1*, but not the N-terminal lytic transglycosylase domain, restores T pili containing VirB2 and VirB5. T-pilus preparations also contain extracellular VirB1*. Protein-protein interactions between VirB1* and VirB2 and VirB5 were detected in the yeast two-hybrid assay. We propose that VirB1 is a bifunctional protein required for
vir
T4SS assembly. The N-terminal lytic transglycosylase domain provides localized lysis of the peptidoglycan cell wall to allow insertion of the T4SS. The C-terminal VirB1* promotes T-pilus assembly through protein-protein interactions with T-pilus subunits.
In Vivo Oligomerization of the F Conjugative Coupling Protein TraD
Authors: Haft Rembrandt J. F. , Gachelet Eliora G. , Nguyen Tran , Toussaint Luttrell , Chivian Dylan , Traxler Beth
Published: July 2007

Type IV secretory systems are a group of bacterial transporters responsible for the transport of proteins and nucleic acids directly into recipient cells. Such systems play key roles in the virulence of some pathogenic organisms and in conjugation-mediated horizontal gene transfer. Many type IV systems require conserved “coupling proteins,” transmembrane polypeptides that are critical for transporting secreted substrates across the cytoplasmic membrane of the bacterium. In vitro evidence suggests that the functional form of coupling proteins is a homohexameric, ring-shaped complex. Using a library of tagged mutants, we investigated the structural and functional organization of the F plasmid conjugative coupling protein TraD by coimmunoprecipitation, cross-linking, and genetic means. We present direct evidence that coupling proteins form stable oligomeric complexes in the membranes of bacteria and that the formation of some of these complexes requires other F-encoded functions. Our data also show that different regions of TraD play distinct roles in the oligomerization process. We postulate a model for in vivo oligomerization and discuss the probable participation of individual domains of TraD in each step.
Pseudomonas aeruginosa
Psl Is a Galactose- and Mannose-Rich Exopolysaccharide
Authors: Ma Luyan , Lu Haiping , Sprinkle April , Parsek Matthew R. , Wozniak Daniel J.
Published: July 2007

The
Pseudomonas aeruginosa
polysaccharide synthesis locus (
psl
) is predicted to encode an exopolysaccharide which is critical for biofilm formation. Here we used chemical composition analyses and mannose- or galactose-specific lectin staining, followed by confocal laser scanning microscopy and electron microscopy, to show that Psl is a galactose-rich and mannose-rich exopolysaccharide.
Chronic sodium hydrosulfide treatment decreases medial thickening of intramyocardial coronary arterioles, interstitial fibrosis, and ROS production in spontaneously hypertensive rats
Authors: Shi Ying-Xian , Chen Ying , Zhu Yi-Zhun , Huang Guo-Ying , Moore Philip Keith , Huang Shan-Hong , Yao Tai , Zhu Yi-Chun
Published: July 2007

Hydrogen sulfide (H2S) is a gasotransmitter that regulates cardiovascular functions. The present study aimed to examine the hypothesis that chronic treatment with sodium hydrosulfide (NaHS, an H2S donor) is able to prevent left-ventricular remodeling in spontaneously hypertensive rats (SHR). Four-week-old SHR were treated with NaHS (10, 30, and 90 μmol·kg−1·day−1), a combination of NaHS (30 μmol·kg−1·day−1) and glibenclamide (5 mg·kg−1·day−1), glibenclamide alone (5 mg·kg−1·day−1), hydralazine alone (10 mg·kg−1·day−1), and placebo for 3 mo. At the end of the treatment period, variables such as cardiac geometry and function, intramyocardial arterioles ranging in diameter from 25 to 100 μm, perivascular and interstitial collagen content, reactive oxygen species (ROS), thiol groups, conjugated dienes, and DNA base modification were examined. The novel finding of the present study is that chronic NaHS treatment prevented the hypertrophy of intramyocardial arterioles and ventricular fibrosis, as well as decreased myocardial ROS and conjugated diene levels. The cardioprotective effects were blunted by coadministration of glibenclamide, suggesting a role of ATP-sensitive potassium channels in mediating the action of NaHS. Hydralazine caused a comparable reduction of blood pressure compared with NaHS treatment; however, it exerted no effect on the remodeling process or on ROS and conjugated diene levels. Moreover, NaHS treatment caused an increase in myocardial thiol group levels, whereas DNA base modification was not altered by NaHS treatment. In conclusion, the superior cardioprotective effects of NaHS treatment are worthy to be further explored to develop novel therapeutic approaches for the treatment of cardiac remodeling in hypertension.
Cerebral microvascular dilation during hypotension and decreased oxygen tension: a role for nNOS
Authors: Bauser-Heaton Holly D. , Bohlen H. Glenn
Published: July 2007

Endothelial (eNOS) and neuronal nitric oxide synthase (nNOS) are implicated as important contributors to cerebral vascular regulation through nitric oxide (NO). However, direct in vivo measurements of NO in the brain have not been used to dissect their relative roles, particularly as related to oxygenation of brain tissue. We found that, in vivo, rat cerebral arterioles had increased NO concentration ([NO]) and diameter at reduced periarteriolar oxygen tension (Po2) when either bath oxygen tension or arterial pressure was decreased. Using these protocols with highly selective blockade of nNOS, we tested the hypothesis that brain tissue nNOS could donate NO to the arterioles at rest and during periods of reduced perivascular oxygen tension, such as during hypotension or reduced local availability of oxygen. The decline in periarteriolar Po2by bath manipulation increased [NO] and vessel diameter comparable with responses at similarly decreased Po2during hypotension. To determine whether the nNOS provided much of the vascular wall NO, nNOS was locally suppressed with the highly selective inhibitor N-(4S)-(4-amino-5-[aminoethyl]aminopentyl)- N′-nitroguanidine. After blockade, resting [NO], Po2, and diameters decreased, and the increase in [NO] during reduced Po2or hypotension was completely absent. However, flow-mediated dilation during occlusion of a collateral arteriole did remain intact after nNOS blockade and the vessel wall [NO] increased to ∼80% of normal. Therefore, nNOS predominantly increased NO during decreased periarteriolar oxygen tension, such as that during hypotension, but eNOS was the dominant source of NO for flow shear mechanisms.
Cytoprotective effects ofN,N,N-trimethylsphingosine during ischemia- reperfusion injury are lost in the setting of obesity and diabetes
Authors: Gundewar Susheel , Calvert John W. , Elrod John W. , Lefer David J.
Published: July 2007

N, N, N-Trimethylsphingosine chloride (TMS), a stable N-methylated synthetic sphingolipid analog, has been shown to modulate protein kinase C (PKC) activity and exert a number of important biological effects, including inhibition of tumor cell growth and metastasis, inhibition of leukocyte migration and respiratory burst, and inhibition of platelet aggregation. We hypothesized that TMS would be cytoprotective in clinically relevant in vivo murine models of myocardial and hepatic ischemia-reperfusion (I/R) injury. Wild-type, obese ( ob/ ob), and diabetic ( db/ db) mice were subjected to 30 min of left coronary artery occlusion followed by 24 h of reperfusion in the myocardial I/R model. In additional studies, mice were subjected to 45 min of hepatic artery occlusion followed by 5 h of reperfusion. TMS was administered intravenously at the onset of ischemia. Myocardial infarct size, cardiac function, and serum liver enzymes were measured to assess the extent of tissue injury. TMS attenuated myocardial infarct size by 66% in the wild type and by 36% in the ob/ ob mice. Furthermore, TMS reduced serum alanine transaminase levels by 43% in wild-type mice. These benefits did not extend to the ob/ ob mice following hepatic I/R or to the db/ db mice following both myocardial and hepatic I/R. A likely mechanism is the failure of TMS to inhibit PKC-δ translocation in the diseased heart. These data suggest that although TMS is cytoprotective following I/R in normal animals, the cytoprotective actions of TMS are largely attenuated in obese and diabetic animals.
Ovariectomy is protective against renal injury in the high-salt-fed older mRen2.Lewis rat
Authors: Yamaleyeva Liliya M. , Pendergrass Karl D. , Pirro Nancy T. , Gallagher Patricia E. , Groban Leanne , Chappell Mark C.
Published: July 2007

Studies in experimental animals and younger women suggest a protective role for estrogen; however, clinical trials may not substantiate this effect in older females. Therefore, the present study assessed the outcome of ovariectomy in older mRen2.Lewis rats subjected to a high-salt diet for 4 wk. Intact or ovariectomized (OVX, 15 wk of age) mRen2.Lewis rats were aged to 60 wk and then placed on a high-salt (HS, 8% sodium chloride) diet for 4 wk. Systolic blood pressures were similar between groups [OVX 169 ± 6 vs. Intact 182 ± 7 mmHg; P = 0.22] after the 4-wk diet; however, proteinuria [OVX 0.8 ± 0.2 vs. Intact 11.5 ± 2.6 mg/mg creatinine; P < 0.002, n = 6], renal interstitial fibrosis, glomerular sclerosis, and tubular casts were lower in OVX vs. Intact rats. Kidney injury molecule-1 mRNA, a marker of tubular damage, was 53% lower in the OVX HS group. Independent from blood pressure, OVX HS rats exhibited significantly lower cardiac (24%) and renal (32%) hypertrophy as well as lower C-reactive protein (28%). Circulating insulin-like growth factor-I (IGF-I) levels were not different between the Intact and OVX groups; however, renal cortical IGF-I mRNA and protein were attenuated in OVX rats [ P < 0.05, n = 6]. We conclude that ovariectomy in the older female mRen2.Lewis rat conveys protection against salt-dependent increase in renal injury.
Cooperative effects of rhinovirus and TNF-α on airway epithelial cell chemokine expression
Authors: Newcomb Dawn C. , Sajjan Umadevi S. , Nagarkar Deepti R. , Goldsmith Adam M. , Bentley J. Kelley , Hershenson Marc B.
Published: July 2007

Rhinovirus (RV) infections trigger exacerbations of airways disease, but underlying mechanisms remain unknown. We hypothesized that RV and cytokines present in inflamed airways combine to induce augmented airway epithelial cell chemokine expression, promoting further inflammation. To test this hypothesis in a cellular system, we examined the combined effects of RV39 and TNF-α, a cytokine increased in asthma and chronic obstructive pulmonary disease, on airway epithelial cell proinflammatory gene expression. Costimulation of 16HBE14o- human bronchial epithelial cells and primary mucociliary-differentiated tracheal epithelial cells with RV and TNF-α induced synergistic increases in IL-8 and epithelial neutrophil attractant-78 production. Similar synergism was observed for IL-8 promoter activity, demonstrating that the effect is transcriptionally mediated. Whereas increases in ICAM-1 expression and viral load were noted 16–24 h after costimulation, cooperative effects between RV39 and TNF-α were evident 4 h after stimulation and maintained despite incubation with blocking antibody to ICAM-1 given 2 h postinfection or UV irradiation of virus, implying that effects were not solely due to changes in ICAM-1 expression. Furthermore, RV39 infection induced phosphorylation of ERK and transactivation of the IL-8 promoter AP-1 site, which functions as a basal level enhancer, leading to enhanced TNF-α responses. We conclude that RV infection and TNF-α stimulation induce cooperative increases in epithelial cell chemokine expression, providing a cellular mechanism for RV-induced exacerbations of airways disease.
Involvement of KATPand KvLQT1 K+channels in EGF-stimulated alveolar epithelial cell repair processes
Authors: Trinh Nguyen Thu Ngan , Privé Anik , Kheir Lina , Bourret Jean-Charles , Hijazi Tiba , Amraei Mohammad Gholi , Noël Josette , Brochiero Emmanuelle
Published: July 2007

Several respiratory diseases are associated with extensive damage of lung epithelia, and the regulatory mechanisms involved in their regeneration are not clearly defined. Growth factors released by epithelial cells or fibroblasts from injured lungs are important regulators of alveolar repair by stimulating cell motility, proliferation, and differentiation. In addition, K+channels regulate cell proliferation/migration and are coupled with growth factor signaling in several tissues. We decided to explore the hypothesis, never investigated before, that K+could play a prominent role in alveolar repair. We employed a model of mechanical wounding of rat alveolar type II epithelia, in primary culture, to study their response to injury. Wound healing was suppressed by one-half upon epidermal growth factor (EGF) titration with EGF-antibody (Ab) or erbB1/erbB2 tyrosine-kinase inhibition with AG-1478/AG-825. The addition of exogenous EGF slightly stimulated the alveolar wound healing and enhanced, by up to five times, alveolar cell migration measured in a Boyden-type chamber. Conditioned medium collected from injured alveolar monolayers also stimulated cell migration; this effect was abolished in the presence of EGF-Ab. The impact of K+channel modulators was examined in basal and EGF-stimulated conditions. Wound healing was stimulated by pinacidil, an ATP-dependent K+channel (KATP) activator, which also increased cell migration, by twofold, in basal conditions and potentiated the stimulatory effect of EGF. KATPor KvLQT1 inhibitors (glibenclamide, clofilium) reduced EGF-stimulated wound healing, cell migration, and proliferation. Finally, EGF stimulated KATPand KvLQT1 currents and channel expression. In summary, stimulation of K+channels through autocrine activation of EGF receptors could play a crucial role in lung epithelia repair processes.
The Politics of Divine Presence: Temple as Locus of Conflict in the Gospel of Mark
Authors: Driggers Ira Brent
Published: July 2007

This paper examines the intersection of theology and politics in the Gospel of Mark as it pertains to Jesus' conflict with the so-called "leaders," giving special attention to the role of the Jerusalem temple within that conflict. It is argued that the temple as cultic institution does not concern the narrator as much as its affiliation with a priestly elite that abuses its God-given authority at the expense of those in need. As the mediator of God's presence Jesus exposes this abuse through a ministry of outreach, meeting rejection by the very ones charged to oversee the "house of God" (2:26; 11:17). This ironic rejection of the divine presence consists of both ignorance (failure to recognize Jesus as God's son) and self-interest (concern for honor and power). Jesus' climactic condemnation of the temple (11:11-25; 13:1-2) thus symbolizes his rejection of its caretakers, the "tenants" once commissioned by God to care for God's own vineyard (12:1-12).
The Lord's House and David's Lord: The Psalms and Mark's Perspective on Jesus and the Temple
Authors: Watts Rikk
Published: July 2007

Four Davidic Psalms (2, 118, 110, and 22), each cited or alluded to at least twice, in this order, and at critical junctures in Mark's narrative, play a key role in his Gospel. In contemporary understanding Psalm 2 was associated with the future messianic purging of Jerusalem and especially the temple (e.g.4QFlor, Pss Sol 17). Psalm 118, concluding the Egyptian Hallel, spoke of Israel's future deliverance under a Davidic king with the restored temple as the goal of Israel's return from exile. Psalm 110's surprisingly elevated royal designation, uniquely expressed in Melchizedekian priestking terms, contributed to several portraits of exalted heavenly deliverers, some messianic, who would preside over Israel's restoration (e.g.11QMelch, 1 Enoch) while Psalm 22's Davidic suffering and vindication described the deliverance of righteous Zion (e.g.4QPs). Drawing from the dual perspective of their original contexts and contemporary interpretations, this paper proposes that Mark's careful arrangement of his psalm citations presents Jesus as both Israel's Davidic Messiah (Pss. 2, 118) and the temple's Lord (Ps. 110) who, coming to purge Jerusalem but rejected by the temple authorities, announces the present structure's destruction and, through his death and vindication (Ps. 22), its replacement with a new people-temple centered on himself.
From Local Strongman to Facilitator
Authors: Andersson Krister , van Laerhoven Frank
Published: July 2007

Efforts to engage citizens in democratic forms of governance in developing societies are complicated by deeply rooted socioeconomic and political inequalities. In this article, the authors analyze the conditions under which local politicians in rural areas of Latin America are likely to open up to citizen participation in governance decisions. The analytical approach focuses on the incentive structures of local politicians under both decentralized and centralized regimes. The argument is that, regardless of regime type, participatory governance institutions are more likely to emerge when the goals of these institutions are compatible with the interests of the local executive. The authors test the argument by analyzing patterns of interaction between central and local governance actors in 390 municipal governments in Brazil, Chile, Mexico, and Peru. They find that local politicians' incentive structures explain a great deal as to why local governments decide to invite citizens to take part in governance activities.
When Is Social Trust a Desirable Outcome?
Authors: Jamal Amaney
Published: July 2007

Levels of both political and social trust tend to play a crucial role in democracies. Yet we have little understanding of the ways in which trust operates in nondemocratic societies. This article finds that levels of political confidence are linked to generalized trust in both democratic and nondemocratic states. In democracies, then, levels of generalized trust may reinforce existing democratic institutions. In nondemocracies, however, generalized trust may be linked to support for authoritarian patterns of rule. This article argues that although generalized trust serves democracy in democratic settings, it is not linked to democratic forms of political and social engagement in the less democratic states of the Arab world.
Economic Origins of Electoral Support for Authoritarian Successors
Authors: Jhee Byong-Kuen
Published: July 2007

This study explores how economic performance prior to democratic transitions affects the fate of successors to authoritarian rulers in new democracies. It investigates 70 founding election outcomes, finding that successful economic performance under an authoritarian regime increases the vote share of successors. It also finds that the past economic performance of authoritarian rulers decreases the likelihood of government alternation to democratic oppositions. Interim governments that initiate democratic transition, however, are neither blamed nor rewarded for economic conditions during transition periods. This study concludes that electorates are not myopic and that economic voting is not a knee-jerk reaction to short-term economic performance in new democracies.
Perspective Taking, Environmental Concern, and the Moderating Role of Dispositional Empathy
Authors: Sevillano Verónica , Aragonés Juan I. , Schultz P. Wesley
Published: July 2007

This article examines the impact of visual images and perspective taking on concern for environmental problems. Participants in the experiment were 193 university students. Results replicated earlier results showing that perspective taking, combined with images of animals harmed by nature, caused an increase in biospheric environmental concerns. In addition, results showed that the empathic dimension of personal distress moderated the relationship between kind of image and kind of perspective on both biospheric and egoistic environmental concerns. Results about the lack of other moderating effects are discussed.
Young Children's Environmental Attitudes and Behaviors
Authors: Evans Gary W. , Brauchle Gernot , Haq Aliya , Stecker Rachel , Wong Kimberly , Shapiro Elan
Published: July 2007

Two reliable and valid instruments to assess first- and second-grade children's ( N = 100, M = 6.8 years) environmental attitudes and behaviors are presented. A series of games derived primarily from dimensions of the new ecological paradigm theory of environmental attitudes are described for the assessment of environmental attitudes. The games include felt board construction, a board game, and an adjustable worry thermometer. Environmental behaviors are assessed in the same sample using magnitude estimation (jumping different distances to indicate frequency of engagement in behavior) based on an adoption of Kaiser's General Environmental Behavior Scale for adults. The behavior scale employs a Rasch measurement model because environmental behaviors are viewed as a consequence of attitudes in concert with difficulties to implement actions.
Thermal Comfort and Outdoor Activity in Japanese Urban Public Places
Authors: Thorsson Sofia , Honjo Tsuyoshi , Lindberg Fredrik , Eliasson Ingegärd , Lim En-Mi
Published: July 2007

Subjective thermal comfort and outdoor activity in a park and a square in a satellite city northeast of Tokyo were investigated through structured interviews, observations, and comprehensive micrometeorological measurements. Results showed that the park was on an average 1.1°C cooler than the square. The relatively warmer thermal conditions in the square in comparison to the park resulted in a heat load of greater intensity for humans in the square. In general, there was a low relation between the thermal environment and the use of the two places in terms of total attendance. However, the use of the park was influenced more by the thermal conditions than by the use of the square, which can mainly be attributed to the different functions of the two places. Finally, examples of the differences between the use of the sun, the attitudes toward it, and outdoor exposure in Japan and Sweden are highlighted and discussed.
Living With the Stigma of Hepatitis C
Authors: Butt Gail , Paterson Barbara L. , McGuinness Liza K.
Published: July 2007

Stigma poses significant challenges to those with chronic hepatitis C (CHC), their social networks, communities, and society. This study's purpose was to identify and describe how people lived with CHC and made self-care decisions. Data are presented from interviews and daily recordings of 26 study participants. Experiences of stigma were attributed primarily to misconceptions about the cause and transmission of the disease and its association with illicit drug use. Perceptions and responses to stigma were context-dependent, flexible, and varied over time. Stigma created barriers to access of health services and undermined the social supports required to address self-care needs and illness management. The extent and severity of stigma suggests that interventions to reduce or eliminate stigma will require individual, structural, and systemic changes. Further study is required to clarify the relationship between the trajectory of CHC and the experience and responses to stigma.
Caregiver Perspectives on Safety in Home Dementia Care
Authors: Lach Helen W. , Chang Yu-Ping
Published: July 2007

Home safety is a significant problem for caregivers of people with Alzheimer's disease and other dementias. This focus group study is designed to gain insight into caregivers' experiences of managing safety issues and to explore application of the transtheoretical model of health behavior change (TTM) to this problem, toward development of interventions to improve safety care. Caregivers identified safety problems and management strategies, as well as barriers and factors facilitating management, that can help guide the development of interventions. Caregivers described different stages of adopting actions to prevent accidents and injuries consistent with the TTM. The TTM warrants further study for understanding how to help caregivers make changes to promote safe care.
Racial Segregation and Differential Outcomes in Hospital Care
Authors: Clarke Sean P. , Davis Bertha L. , Nailon Regina E.
Published: July 2007

This exploratory study of patients in Pennsylvania (PA) and Virginia (VA) hospitals in 1998-1999 measures the segregation of care for Black patients receiving inpatient care for specific medical and surgical conditions. It also examined inpatient mortality risk for Black patients and the impact of treatment in heavily segregated hospitals on mortality for Blacks and non-Blacks. Segregation of hospital care was found across both states but was more pronounced in PA. Blacks did not experience higher mortality rates than non-Blacks either before or after controls for clinical risk factors in either state and for certain admission types had lower mortality. Both Black and non-Black surgical, heart failure, and lung disease patients treated in VA hospitals with more Black patients had poorer outcomes. Future research should examine how access, patient choice, hospital organization, processes of care, and factors related to nursing care might influence hospital outcomes for patients from different racial backgrounds.
Notch signaling induces cytoplasmic CD3ϵ expression in human differentiating NK cells
Authors: De Smedt Magda , Taghon Tom , Van de Walle Inge , De Smet Greet , Leclercq Georges , Plum Jean
Published: July 2007

It has been proposed that heterogeneity in natural killer (NK)–cell phenotype and function can be achieved through distinct thymic and bone marrow pathways of NK-cell development. Here, we show a link between Notch signaling and the generation of intracellular CD3ϵ (cyCD3)–expressing NK cells, a cell population that can be detected in vivo. Differentiation of human CD34+ cord blood progenitors in IL-15–supplemented fetal thymus organ culture or OP9-Delta-like 1 (DL1) coculture resulted in a high percentage of cyCD3+ NK cells that was blocked by the γ-secretase inhibitor DAPT. The requirement for Notch signaling to generate cyCD3+ NK cells was further illustrated by transduction of CD34+ cord blood (CB) cells with either the active intracellular part of Notch or the dominant-negative mutant of mastermind-like protein 1 that resulted in the generation of NK cells with respectively high or low frequencies of cyCD3. Human thymic CD34+ progenitor cells displayed the potential to generate cyCD3+ NK cells, even in the absence of Notch/DL1 signaling. Peripheral blood NK cells were unable to induce cyCD3 expression after DL1 exposure, indicating that Notch-dependent cyCD3 expression can only be achieved during the early phase of NK-cell differentiation.
Mitochondrial DNA analysis of field populations of Helicoverpa armigera (Lepidoptera: Noctuidae) and of its relationship to H. zea
Authors: Behere Gajanan T , Tay Wee Tek , Russell Derek A , Heckel David G , Appleton Belinda R , Kranthi Keshav R , Batterham Philip
Published: July 2007

Background

Helicoverpa armigera and H. zea are amongst the most significant polyphagous pest lepidopteran species in the Old and New Worlds respectively. Separation of H. armigera and H. zea is difficult and is usually only achieved through morphological differences in the genitalia. They are capable of interbreeding to produce fertile offspring. The single species status of H. armigera has been doubted, due to its wide distribution and plant host range across the Old World. This study explores the global genetic diversity of H. armigera and its evolutionary relationship to H zea.

Results

We obtained partial (511 bp) mitochondrial DNA (mtDNA) Cytochrome Oxidase-I (COI) sequences for 249 individuals of H. armigera sampled from Australia, Burkina Faso, Uganda, China, India and Pakistan which were associated with various host plants. Single nucleotide polymorphisms (SNPs) within the partial COI gene differentiated H. armigera populations into 33 mtDNA haplotypes. Shared haplotypes between continents, low F-statistic values and low nucleotide diversity between countries (0.0017 – 0.0038) suggests high mobility in this pest. Phylogenetic analysis of four major Helicoverpa pest species indicates that H. punctigera is basal to H. assulta, which is in turn basal to H. armigera and H. zea. Samples from North and South America suggest that H. zea is also a single species across its distribution. Our data reveal short genetic distances between H. armigera and H. zea which seem to have been established via a founder event from H. armigera stock at around 1.5 million years ago.

Conclusion

Our mitochondrial DNA sequence data supports the single species status of H. armigera across Africa, Asia and Australia. The evidence for inter-continental gene flow observed in this study is consistent with published evidence of the capacity of this species to migrate over long distances. The finding of high genetic similarity between Old World H. armigera and New World H. zea emphasises the need to consider work on both pests when building pest management strategies for either.
Anxiety and depression in patients with gastrointestinal cancer: does knowledge of cancer diagnosis matter?
Authors: Tavoli Azadeh , Mohagheghi Mohammad Ali , Montazeri Ali , Roshan Rasool , Tavoli Zahra , Omidvari Sepideh
Published: July 2007

Background

Gastrointestinal cancer is the first leading cause of cancer related deaths in men and the second among women in Iran. An investigation was carried out to examine anxiety and depression in this group of patients and to investigate whether the knowledge of cancer diagnosis affect their psychological distress.

Methods

This was a cross sectional study of anxiety and depression in patients with gastrointestinal cancer attending to the Tehran Cancer Institute. Anxiety and depression was measured using the Hospital Anxiety and Depression Scale (HADS). This is a widely used valid questionnaire to measure psychological distress in cancer patients. Demographic and clinical data also were collected to examine anxiety and depression in sub-group of patients especially in those who knew their cancer diagnosis and those who did not.

Results

In all 142 patients were studied. The mean age of patients was 54.1 (SD = 14.8), 56% were male, 52% did not know their cancer diagnosis, and their diagnosis was related to esophagus (29%), stomach (30%), small intestine (3%), colon (22%) and rectum (16%). The mean anxiety score was 7.6 (SD = 4.5) and for the depression this was 8.4 (SD = 3.8). Overall 47.2% and 57% of patients scored high on both anxiety and depression. There were no significant differences between gender, educational level, marital status, cancer site and anxiety and depression scores whereas those who knew their diagnosis showed a significant higher degree of psychological distress [mean (SD) anxiety score: knew diagnosis 9.1 (4.2) vs. 6.3 (4.4) did not know diagnosis, P < 0.001; mean (SD) depression score: knew diagnosis 9.1 (4.1) vs. 7.9 (3.6) did not know diagnosis, P = 0.05]. Performing logistic regression analysis while controlling for demographic and clinical variables studied the results indicated that those who knew their cancer diagnosis showed a significant higher risk of anxiety [OR: 2.7, 95% CI: 1.1–6.8] and depression [OR: 2.8, 95% CI: 1.1–7.2].

Conclusion

Psychological distress was higher in those who knew their cancer diagnosis. It seems that the cultural issues and the way we provide information for cancer patients play important role in their improved or decreased psychological well-being.
Comparison of echocardiographic (US) volumetry with cardiac magnetic resonance (CMR) imaging in transfusion dependent thalassemia major (TM)
Authors: Giakoumis Anastasios , Berdoukas Vasilis , Gotsis Efstathios , Aessopos Athanassios
Published: July 2007

Background

Despite advances in survival in patients with thalassemia major (TM) the most common cause of death is cardiac disease. Regular cardiac follow-up is imperative in order to identify and reverse pathology. Cardiac Magnetic Resonance (CMR) and Echocardiography (US) are applied in parallel to TM patients for cardiac evaluation and ongoing monitoring. A comparison between mutual features would be useful in order to assess the accuracy and reliability of the two methods, with a particular focus on routine US application. TM's special attributes offer an excellent opportunity for cardiac imaging research that has universal general purpose applications.

Methods

135 TM patients underwent US (Teichholz's M-mode formula – rapidly accessible means of measuring volumes and ejection fraction) and CMR volumetry. Paired-samples t-test, Passing & Badlock regression and Bland & Altman plot were used while comparing the common parameters between the CMR and the US.

Results

We found that the US volumes were underestimated, especially the end-diastolic volume (p < 0.001). The end-systolic volume showed a borderline two-tailed probability (p ≈ 0.05). The correlation for the ejection fraction was acceptable (r = 0.60) without a statistically significant difference (p = 0.37) and the Bland Altman plot range was narrow (25.8%). There was a satisfactory correlation of the US' shortening fraction with CMR's ejection fraction (r = 0.58).

Conclusion

In cases where cardiac wall movement abnormalities are absent, the US Teichholz's M-mode formula for volume measurements, though less sophisticated in comparison to the high resolution CMR technique, offers an adequate ejection fraction estimation for routine use, especially when monitoring gross alterations in cardiac function over time, and is easy to perform.
Prospective associations of social self-control with drug use among youth from regular and alternative high schools
Authors: Pokhrel Pallav , Sussman Steve , Rohrbach Louise Ann , Sun Ping
Published: July 2007

Background

This study examined the one year prospective associations between adolescent social self-control and drug outcomes (cigarette use, alcohol use, marijuana use, hard drug use, and problem drug use) among adolescents from regular and continuation high schools. In our previous cross-sectional study, poor social self-control was found to be associated with higher drug use, controlling for 12 personality disorder categories. In this study, we attempted to find out (a) whether lack of social self-control predicted drug use one year later, and (b) whether drug use at baseline predicted social self-control one year later.

Methods

We surveyed 2081 older adolescents from 9 regular (N = 1529) and 9 continuation (alternative) (N = 552) high schools in the Los Angeles area. Data were collected at two time points in an interval of approximately 1 year.

Results

Past 30-day cigarette smoking, marijuana use, hard drug use, and problem drug use at baseline were found to predict lower social self-control at follow-up, controlling for baseline social self-control and demographic variables. The effect of problem drug use as a one-year predictor of social self-control was found to be moderated by school type (regular or continuation high school), such that the relationship was significant for continuation high school students only. Conversely, social self-control was found to predict past 30-day alcohol use, marijuana use, and problem drug use, controlling for baseline drug use and demographic variables. For alcohol use, marijuana use, and problem drug use outcomes, school type was not found to moderate the effects of social self-control, though an interaction effect was found regarding cigarette smoking. Social self-control was a significant predictor of cigarette use only at regular high school.

Conclusion

The results indicate that social self-control and drug use share a reciprocal relationship. Lack of social self-control in adolescents seems to result in increased drug use, which in turn is likely to further decrease social self-control. Thus, it seems that social self-control is an alterable cognitive-behavioral attribute which can be improved through skill-based interventions in order to prevent drug use among adolescents. Policies aimed at preventing drug abuse among adolescents may benefit from institutionalizing social self-control skills training.
Non-invasive measurement of adrenocortical activity in male and female rats
Authors: Lepschy M , Touma C , Hruby R , Palme R
Published: July 2007

Rats are widely used in biomedical research as animal models for human diseases. However, due to their small body size, blood sampling is complicated and invasive and thereby can seriously interfere with endocrine functions and possibly compromise the animals' welfare. Therefore, a non-invasive technique to monitor stress hormones in these animals is highly desired. Our study aimed to gain general information about corticosterone metabolism and excretion and to validate a 5 α-pregnane-3 β,11 β,21-triol-20-one enzyme immunoassay (EIA) to reliably measure faecal corticosterone metabolites (CMs) in laboratory rats. In total, 18 rats were administered 2.3 MBq of 3H-corticosterone intravenously and per os, respectively (intravenous: 6 males and 6 females; per os: 3 males and 3 females). Subsequently, all voided excreta were frequently collected for five days. About 75±9% of the recovered CMs were found in the faeces. Peak concentrations of radiolabelled steroids appeared in the urine after 1.7±0.6 h in males and after 6.0±3.5 h in females. In faeces, maxima were observed after 14.7±2.4 h in both sexes. In principle, the time course and delay for both routes of administration (intravenous or per os) were the same, except for a delay of peak concentrations in urine (4.5±2.1 h) in per os administered males. Using high-performance liquid chromatography (HPLC), faecal 3H-CMs were characterized and differences were found between the sexes. In both sexes, corticosterone was extensively metabolized, but while males showed only minor variations in their CM patterns, those of females differed largely between individuals. To validate the mentioned EIA, we investigated the diurnal variation (DV) of glucocorticoids as well as effects of the injection procedure itself and conducted an adrenocorticotropic hormone challenge test and a dexamethasone suppression test, using six male and six female rats each. Our results demonstrated that pharmacological stimulation, suppression and DV of adrenocortical activity were accurately reflected by means of CM measurement in faeces. By successful physiological validation, we proved for the first time the suitability of an immunoassay to non-invasively monitor adrenocortical activity in rats of both sexes. This method opens up new perspectives for biomedical and pharmacological investigations as well as for animal welfare related issues.