bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis of Human Alphaherpesvirus MicroRNA Expression in Latently Infected Human Trigeminal Ganglia
Authors: Umbach Jennifer L. , Nagel Maria A. , Cohrs Randall J. , Gilden Donald H. , Cullen Bryan R.
Published: August 2009

Analysis of cells infected by a wide range of herpesviruses has identified numerous virally encoded microRNAs (miRNAs), and several reports suggest that these viral miRNAs are likely to play key roles in several aspects of the herpesvirus life cycle. Here we report the first analysis of human ganglia for the presence of virally encoded miRNAs. Deep sequencing of human trigeminal ganglia latently infected with two pathogenic alphaherpesviruses, herpes simplex virus 1 (HSV-1) and varicella-zoster virus (VZV), confirmed the expression of five HSV-1 miRNAs, miR-H2 through miR-H6, which had previously been observed in mice latently infected with HSV-1. In addition, two novel HSV-1 miRNAs, termed miR-H7 and miR-H8, were also identified. Like four of the previously reported HSV-1 miRNAs, miR-H7 and miR-H8 are encoded within the second exon of the HSV-1 latency-associated transcript. Although VZV genomic DNA was readily detectable in the three human trigeminal ganglia analyzed, we failed to detect any VZV miRNAs, suggesting that VZV, unlike other herpesviruses examined so far, may not express viral miRNAs in latently infected cells.
Intestinal intussusception in adults due to acute enterovirus infection
Authors: Chia A Y , Chia J K
Published: August 2009

Three adult cases of intussusceptions, associated with enteroviruses occurring within a 3-week period, are reported. Virological studies include viral RNA detection in stool samples and staining for enterovirus protein by immunoperoxidase staining of the resected intestinal tissues. A new mechanism for intussusception associated with enterovirus is proposed. Tap water was implicated in the outbreak. Better monitoring of drinking-water may prevent other cases of non-polio enterovirus infection.
Coarse particles and mortality: evidence from a multi-city study in California
Authors: Malig B J , Ostro B D
Published: August 2009

Objective:

To examine the risk of all-cause and cardiovascular mortality associated with short-term coarse particle exposure in California while addressing issues of exposure misclassification by limiting the study to those residing near a pollution monitor.

Methods:

Deaths in 15 California counties from 1999 to 2005 were linked to coarse particulate monitoring data. Case deaths were limited to those residing in a zip code within 20 km of a pollution monitor. We used conditional logistic regression with a case-crossover design to estimate county-specific effects of coarse particles. County estimates were then pooled using random-effects meta-analysis to create overall study estimates. Effects specific to race and educational status were also analysed.

Results:

We observed an increased excess risk (ER) of both all-cause mortality (ER per 10 μg/m3 = 0.7%, 95% CI −0.1 to 1.5) and cardiovascular mortality (ER per 10 μg/m3 = 1.3%, 95% CI 0.1 to 2.5) from a 2-day lag in coarse particles. Greater effects were observed among Hispanics and non-high school graduates. Adjustment for fine particles and decreasing the inclusion buffer to 10 km did not substantively alter the results.

Conclusions:

Our study provides further evidence of an association between acute exposure to coarse particles and mortality, and supports the hypothesis that lower socioeconomic status groups may be more susceptible to its effects.
An examination of the effect on cigarette prices and promotions of Philip Morris USA penalties to stores that sell cigarettes to minors: Table 1
Authors: Feighery E C , Schleicher N C , Ribisl K M , Rogers T
Published: August 2009

Objective:

The purpose of this study was to assess the potential impact of public policies to regulate price discounting strategies on retail cigarette prices and advertising. Philip Morris USA (PM USA) has a policy designed to sanction stores violating state laws banning illegal tobacco sales to minors by temporarily suspending price discounting incentives. This study examined the impact of those sanctions on retail cigarette prices and sales promotion advertising.

Method:

In November 2006, the California Attorney General’s Office informed PM USA that 196 stores were found guilty of illegal underage sales. Of these, 109 stores that participated in the PM USA Retail Leaders Program were notified that their merchandising and/or promotional resources would be suspended for the month of April 2007. The remaining 87 stores were not sanctioned and served as a comparison group. Trained raters assessed advertising and prices of selected PM USA brands in these stores pre-penalty and during the penalty phase.

Results:

There were no significant differences between sanctioned and non-sanctioned stores on median changes in price and sales promotion advertising from the pre-penalty to the penalty phase.

Conclusion:

The lack of impact on cigarette prices and advertising indicate that the PM USA policy may be flawed in its design or execution. If public policies are developed to restrain cigarette price discounting strategies, they should be crafted to ensure compliance and preclude possible compensatory actions by retailers.
Methods of the International Tobacco Control (ITC) China Survey
Authors: Wu Changbao , Thompson Mary E , Fong Geoffrey T , Li Qiang , Jiang Yuan , Yang Yan , Feng Guoze
Published: August 2009

This paper describes the design features, data collection methods and analytical strategies of the ITC China Survey, a prospective cohort study of 800 adult smokers and 200 adult non-smokers in each of six cities in China . In addition to features and methods which are common to ITC surveys in other countries, the ITC China Survey possesses unique features in frame construction, a large first phase data enumeration and sampling selection; and it uses special techniques and measures in training, field work organisation and quality control. It also faces technical challenges in sample selection and weight calculation when some selected upper level clusters need to be replaced by new ones owing to massive relocation exercises within the cities.
Distinguishing risk factors for the onset of cravings, withdrawal symptoms and tolerance in novice adolescent smokers
Authors: Wileyto P , O’Loughlin J , Lagerlund M , Meshefedjian G , Dugas E , Gervais A
Published: August 2009

Aim:

While many studies report determinants of adolescent cigarette smoking, few identify risk factors for nicotine dependence (ND). This study distinguished between risk factors for three hallmarks of ND including cravings, withdrawal symptoms and tolerance.

Methods:

A total of 319 novice smokers were followed every 3 months from first puff on a cigarette until the end of secondary school. Outcomes included time to first report of cravings, withdrawal symptoms and tolerance.

Results:

Female sex, inhalation, smoking a whole cigarette, weekly smoking, daily smoking and alcohol use each independently increased the incidence of the onset of cravings. Inhalation, weekly smoking, daily smoking and alcohol use predicted the onset of withdrawal symptoms. Withdrawal symptoms, smoking a whole cigarette, monthly smoking, daily smoking and friends and siblings smoking increased the incidence of the onset of tolerance. None of parental education, impulsivity, novelty seeking, self-esteem, depression, stress, parental smoking, physical activity, or participation in sports teams was associated with the outcomes.

Conclusion:

The hallmarks of early ND are related to intensity and frequency of cigarette use. Avoidance of daily smoking may be particularly important in preventing the onset of ND symptoms and sustained smoking.
Estimating missed government tax revenue from foreign tobacco: survey of discarded cigarette packs: Table 1
Authors: Wilson N , Thomson G , Edwards R , Peace J
Published: August 2009

Aim:

To clarify the extent of use of foreign (including duty free, foreign normal retail and smuggled) tobacco, and to estimate missed government tax revenue in a geographically isolated country.

Methods:

Discarded cigarette packs were collected on the streets of four cities and six New Zealand towns/rural locations between November 2008 and January 2009.

Results:

Out of a total of 1310 packs collected, 42 foreign packs were identified (3.2%, 95% CI 2.4% to 4.3%). Overall, the distribution of packs by country and company was not suggestive of any clustering that might indicate smuggling. At 3.2% of packs being “foreign”, the New Zealand government is losing around $36 million per year in tobacco-related tax relative to if all this tobacco was purchased in New Zealand. For various reasons (including that it was not possible to identify packs bought duty free within New Zealand, and other New Zealand survey data indicating duty free product use at 3.8% of packs), the figure reached is probably an underestimate of the true level.

Conclusion:

The New Zealand government is missing out on revenue that could be used for improving the funding of tobacco control, and smokers are being exposed to cheaper tobacco thus increasing their risk of continuing to smoke. This government and other governments can and should act at the international and national levels to end the sales of duty free tobacco.
Response of an aquifer near Ottawa to tidal forcing and the Alaskan earthquake of 1964
Authors: Bower D. R. , Heaton K. C.
Published: August 2009

Coincident with the Alaskan event the water level in a deep well near Ottawa showed a small initial rise then a fall of 28 cm followed by a decay back to the original level over a period of several days. This is suggestive of a residual dilatation with subsequent fluid diffusion. It is shown that this explanation is consistent with the diffusion and elastic properties of the aquifer determined independently from a slug test and from the response to earth tides. Assuming a simple unconfined saturated porous half-space, the results indicate that the upper 200 m (approximately) is effectively decoupled from horizontal stresses whereas below this depth a permanent dilatation of approximately 2.9 × 10−7 occurred. This is much too large and of the wrong sign to be accounted for by the residual strain field of the earthquake. As an alternative, dilatancy induced by strong local ground motion is suggested.
The troughs at the rear of the New Hebrides island arc: Possible mechanisms of formation
Authors: Dubois Jacques , Dugas François , Lapouille André , Louat rémy
Published: August 2009

A geomorphological description of the tectonic troughs behind the volcanic arc is provided from data gathered in the New Hebrides island arc. From bathymetry and seismic reflection profiles, a representative plan of these troughs is made. From front to rear, the arc sequence is generally a small depression, followed by a wide, deep depression with a narrow ridge along either side. Stratigraphy and tectonics clearly show that the troughs were induced by crustal stretching; sedimentary formations observed are thought to be Plio-Quaternary. Magnetic anomalies on several profiles, and some gravimetric data, show information on the deep structure and genesis of the troughs. We conclude from the data that these recently faulted basins are symmetrical about the longitudinal axis where rising magma is causing uplift.Three possible mechanisms are suggested for the formation of the troughs. The most likely is that transcurrent faults occurred in the curved parts of the arcs, after which convection cells appeared in the asthenosphere above the Benioff zone. The rising columns of the converting cells caused tensional tectonic movement beneath the troughs along pre-existing fault lines. Ascending material then formed intrusions, creating magnetic anomalies.
Revisions to the stratigraphy and biochronology of the Upper Cretaceous Nanaimo Group, British Columbia and Washington State
Authors: Ward Peter D.
Published: August 2009

The stratigraphy of the Upper Cretaceous Nanaimo Group of the Vancouver Island region is revised on the bases of new fossil and field data. Previously unrecognized turbidite facies of the Haslam Formation are proposed as the new Cowichan Member of the Haslam Formation. This member either overlies or intertongues with the new Haslam Creek Member of the Haslam Formation. The Extension–Protection Formation is subdivided into three formations: the lower Extension Formation, the middle Pender Formation (new name) and the upper Protection Formation.The macrofossil zonal succession can be revised to include a new local-range zone superjacent to the Schmidti Zone and subjacent to the Vancouverense Zone named the Chicoensis Zone, based on the Nanaimo Group occurrences of Baculites chicoensis Trask and Submortoniceras chicoense (Trask). Another new zone is proposed superjacent to the Vancouverense Zone and subjacent to the Suciaensis Zone, named the Paciflcum Zone. This latter zone is based on the local Nanaimo Group ranges of Metaplacenticeras cf. M. pacificum (Smith) and Baculites rex Anderson.
The determination of sedimentation rates in Lake Ontario using the 210Pb dating method
Authors: Farmer John G.
Published: August 2009

The 210Pb dating method has been applied successfully to the determination of recent sedimentation rates at four sites distributed among the three major sedimentary basins (Niagara, Mississauga and Rochester) of Lake Ontario. Following correction for effects due to compaction of the sediments, mean sedimentation rates ranging from 0.02 cm/year at the periphery of the Mississauga basin to 0.11 cm/year in the Niagara and Rochester basins were determined. Allowance for compaction reduced the non-compaction-corrected sedimentation rates by 20–35%. Neither 210Pb nor fallout 137Cs profiles indicated surface mixing of sediment sufficient to noticeably affect the calculated sedimentation rates. At all four sites, the sedimentation rate seems to have remained constant during the last 100–150 years.
Lead-isotope geochronology of the Portman Lake area, Northwest Territories
Authors: Stevenson R. , Cumming G. L. , Krstic D.
Published: August 2009

An area of Archean rocks extending from northwestern Saskatchewan into the Northwest Territories is referred to as the Nolan block.Whole rocks and minerals separated from granodiorite surrounding an occurrence of amazonite at Portman Lake in the centre of this block have been studied in some detail using several dating techniques. The following ages result: [Formula: see text] on abraded zircons from the granodiorite; 2589 ± 4 Ma whole-rock Pb/Pb age of the granodiorite; 2561 ± 6 and 2475 ± 13 Ma internal Pb/Pb isochrons; and 2610 ± 10 Ma Pb/Pb model ages on galena and amazonite.Pb/Pb internal isochrons were obtained by successive leaching of whole-rock samples and apparently indicate episodes of minor resetting of the whole-rock system. The close agreement between zircon ages, whole-rock Pb/Pb isochrons, and model ages on galena with no indication of Hudsonian updating suggest that the area has been essentially undisturbed since the Archean. The internal isochrons seem similar to Rb/Sr dates in the area and may indicate similarities in thermal response of the Rb–Sr and U–Pb systems in rocks.
A quantitative analysis of lithospheric subsidence due to thinning by simple shear
Authors: Mudford Brett S.
Published: August 2009

Kinematic simple-shear models have recently been used to provide qualitative explanations for tectonic features in the Basin and Range Province of the southwestern United States and on passive margins. In this paper, a general kinematic simple-shear model is presented. Explicit expressions for the subsidence and stretching factors across a simple-shear zone are derived for two important cases. The first case is one in which simple-shear rifting occurs along a major fault that cuts through the whole lithosphere. In the second case, simple-shear thinning takes place in a brittle zone overlying a regional ductile zone that is undergoing pure-shear thinning. In these cases the subsidence and stretching factors both have characteristic distributions across the stretched region, which can indicate the dominant mode of rifting. It is also shown that simple-shear rifting under the assumption of local isostatic compensation cannot lead to the production of uplifted metamorphic core complexes unless some additional mechanism such as crustal underplating is operating.
Anatomy of a large-scale braid-plain quartzarenite from the Neoproterozoic Shaler Group, Victoria Island, Northwest Territories, Canada
Authors: Rainbird Robert H.
Published: August 2009

The Neoproterozoic Kuujjua Formation is an up to 120 m thick, texturally submature quartzarenite typified by laterally persistent tabular planar cosets of simple and compound planar crossbedding, intercalated with rare, thin dolomitic siltstone lenses up to tens of kilometres wide. It is interpreted as the deposit of a big river, occupying a braid plain, at least 150 km wide, which flowed into the Amundsen Basin from the southeast. The dominant elements of this deposit are stacked tabular and laterally continuous compound crossbeds, interpreted as very large channel forms, which migrated mainly by lateral accretion of superposed small- to moderate-scale two-dimensional dunes. Simple planar crossbedding represents moderate to large two-dimensional periodic bedforms deposited in channels. Rare trough crossbedding represents three-dimensional dunes, which probably were deposited in narrow low-stage chutes that cut across the larger bedforms. Dolomitic siltstone lenses are interpreted as deposits of large flood basin playa lakes that were periodically rejuvenated by river floods. Unrestricted migration of the channels back and forth across the braid plain reworked many of the thin lake deposits and produced the observed multistoried sandstone sheet geometry. A prevailing arid climate is indicated by the occurrence of evaporite casts and pseudomorphs in the flood-basin deposits. The Kuujjua Formation shares features with deposits of the Brahmaputra River; however, there appear to be no modern analogues for the thick, large-scale braided-stream deposits that characterized many Proterozoic cratonic basins.
Le Groupe de la Hutte Sauvage: sédimentation alluvionnaire épi-orogénique dans l'arrière-pays de la fosse du Labrador (Protérozoïque inférieur, Nouveau-Québec)
Authors: Girard Réjean
Published: August 2009

The Hutte Sauvage Group is an epicontinental siliciclastic sedimentary sequence deposited onto polycyclic gneiss of the Rae Province, between the New-Québec (Labrador trough) and Torngat Lower Proterozoic orogens. Bounded to the west by the George River shear zone, the Hutte Sauvage Group shows an asymmetric facies distribution. From west to east, and from base to top, it is made of talus conglomerate, alluvial fan arkose, and wacke–quartzite assemblage of probable fluvial origin. The talus conglomerate includes fragments from lithodemic units to the west, indicative of a local derivation. Boulders from the De Pas Batholith imply a maximum age of 1.84 Ga for the onset of sedimentation. Structural analysis of the basement faults, along with the sedimentary facies analysis, suggest erosion and sedimentation along a fault scarp affected by normal scissors-like movement coinciding with the George River shear zone. The Hutte Sauvage Group deposition being younger than the regional transcurrent shearing and the arc magmatism episode, the group is therefore considered to be the youngest supracrustal assemblage preserved in the New-Québec and Torngat orogens.
Autonomic effects on the spectral analysis of heart rate variability after exercise
Authors: Ng Jason , Sundaram Sri , Kadish Alan H. , Goldberger Jeffrey J.
Published: August 2009

Although frequency-domain analysis of heart rate variability (HRV) has been performed in the setting of exercise and recovery from exercise, the relationship of specific frequency components to sympathetic and parasympathetic inputs has not been validated in this setting. The aim of this study is to evaluate the relationship of frequency components of HRV to sympathetic and parasympathetic modulation in the setting of recovery after exercise using selective autonomic blockade. Normal subjects ( n = 27, 17 men, 53 ± 7 yr old) underwent bicycle stress testing on four separate days. On day 1, a baseline study without autonomic blockade was performed. On days 2 through 4, either β-adrenergic, parasympathetic, or double blockade was administered during exercise and completed 3 min before recovery. Continuous ECG was recorded for 5 min starting from the end of exercise. Time- and frequency-domain measures of HRV were computed for each of the five 1-min segments of RR intervals. Parasympathetic blockade significantly decreased all the HRV measures compared with baseline ( P < 0.02 for all). Root mean square of successive differences of RR intervals (rMSSD) was increased by β-adrenergic blockade ( P < 0.0002). All the HRV measures except rMSSD showed increases with time after the first minute of recovery. The low frequency-to-high frequency ratio did not respond to autonomic blockade or to recovery time, consistent with the expected changes in sympathovagal influence. Root mean square (detrended SD) and rMSSD were highly correlated with the square root of the total power ( r = 0.96) and high-frequency power ( r = 0.95), respectively. Although there are marked reductions in the frequency-domain measures in recovery versus rest, the fluctuations in the low- and high-frequency bands respond to autonomic blockade in the expected fashion. Time-domain measures of HRV were highly correlated with frequency-domain measures and therefore provide a computationally more efficient assessment of autonomic influences during recovery from exercise that is less susceptible to anomalies of frequency-domain analysis.
Impact of ionic current variability on human ventricular cellular electrophysiology
Authors: Romero Lucía , Pueyo Esther , Fink Martin , Rodríguez Blanca
Published: August 2009

Abnormalities in repolarization and its rate dependence are known to be related to increased proarrhythmic risk. A number of repolarization-related electrophysiological properties are commonly used as preclinical biomarkers of arrhythmic risk. However, the variability and complexity of repolarization mechanisms make the use of cellular biomarkers to predict arrhythmic risk preclinically challenging. Our goal is to investigate the role of ionic current properties and their variability in modulating cellular biomarkers of arrhythmic risk to improve risk stratification and identification in humans. A systematic investigation into the sensitivity of the main preclinical biomarkers of arrhythmic risk to changes in ionic current conductances and kinetics was performed using computer simulations. Four stimulation protocols were applied to the ten Tusscher and Panfilov human ventricular model to quantify the impact of ±15 and ±30% variations in key model parameters on action potential (AP) properties, Ca2+ and Na+ dynamics, and their rate dependence. Simulations show that, in humans, AP duration is moderately sensitive to changes in all repolarization current conductances and in L-type Ca2+ current ( ICaL) and slow component of the delayed rectifier current ( IKs) inactivation kinetics. AP triangulation, however, is strongly dependent only on inward rectifier K+ current ( IK1) and delayed rectifier current ( IKr) conductances. Furthermore, AP rate dependence (i.e., AP duration rate adaptation and restitution properties) and intracellular Ca2+ and Na+ levels are highly sensitive to both ICaL and Na+/K+ pump current ( INaK) properties. This study provides quantitative insights into the sensitivity of preclinical biomarkers of arrhythmic risk to variations in ionic current properties in humans. The results show the importance of sensitivity analysis as a powerful method for the in-depth validation of mathematical models in cardiac electrophysiology.
Sphingosine 1-phosphate is an important endogenous cardioprotectant released by ischemic pre- and postconditioning
Authors: Vessey Donald A. , Li Luyi , Honbo Norman , Karliner Joel S.
Published: August 2009

Exogenous sphingosine 1-phosphate (S1P) is an effective cardioprotectant against ischemic injury. We have investigated the hypothesis that S1P is also an important endogenous cardioprotectant released during both ischemic preconditioning (IPC) and ischemic postconditioning (IPOST). IPC of ex vivo rat hearts was instituted by two cycles of 3 min ischemia-5 min reperfusion prior to 40 min of index ischemia and then 40 min of reperfusion. IPC resulted in 70% recovery of left ventricular developed pressure (LVDP) upon reperfusion and a small infarct size (10%). VPC23019 (VPC), a specific antagonist of S1P1 and 3 G protein-coupled receptors (GPCRs), when present during preconditioning blocked protection afforded by two cycles of IPC. VPC also blocked preconditioning of isolated rat cardiac myocytes subjected to hypoxia-reoxygenation injury. Increased release of S1P from myocytes in response to IPC was also demonstrated. These data indicate that S1P is released from myocytes in response to IPC and protects by binding to S1P GPCRs. In the ex vivo heart, if a third cycle of IPC was added to increase release of endogenous mediators, then the need for any individual mediator (e.g., S1P) was diminished and VPC had little effect. The adenosine antagonist 8-( p-sulfophenyl)-theophylline (8-SPT) likewise inhibited protection by two cycles but not three cycles of IPC, but VPC plus 8-SPT inhibited protection by three cycles of IPC. Similar to IPC, IPOST induced by four postindex ischemia cycles of 15 s reperfusion-15 s ischemia resulted in 66% recovery of LVDP and a 7% infarct size. When VPC was present during postconditioning and reperfusion, LVDP only recovered by 26% and the infarct size increased to 27%. Adding an additional cycle of IPOST reduced the inhibitory effect of VPC and 8-SPT individually, but not their combined effect. These studies reveal that S1P is an important mediator of both IPC and IPOST that is released along with adenosine during each cycle of IPC or IPOST.
Interleukin-1α stimulates proinflammatory cytokine expression in human cardiac myofibroblasts
Authors: Turner Neil A. , Das Anupam , Warburton Philip , O'Regan David J. , Ball Stephen G. , Porter Karen E.
Published: August 2009

Cardiac myofibroblasts (CMF) play a key role in infarct repair and scar formation following myocardial infarction (MI) and are also an important source of proinflammatory cytokines. We postulated that interleukin-1α (IL-1α), a potential early trigger of acute inflammation post-MI, could stimulate human CMF to express additional proinflammatory cytokines. Furthermore, we hypothesized that these effects may be modulated by the anti-inflammatory cytokine interleukin-10 (IL-10). Human CMF were cultured from atrial biopsies from multiple patients. Interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), and cardiotrophin-1 (CT-1) mRNA expression and secretion were measured using quantitative real-time RT-PCR and enzyme-linked immunosorbent assay. IL-1α (0.001–10 ng/ml, 0–6 h) stimulated IL-1β, TNF-α, and IL-6 mRNA expression with distinct temporal and concentration profiles, resulting in increased cytokine secretion. The response to IL-1α was much greater than with TNF-α. Neither IL-1α nor TNF-α treatment modulated CT-1 mRNA expression. Immunoblotting with phosphospecific antibodies revealed that IL-1α stimulated the extracellular signal-regulated kinase (ERK)-1/2, p38 mitogen-activated protein kinase (MAPK), c-Jun NH2-terminal kinase (JNK), phosphatidylinositol 3-kinase (PI 3-kinase)/protein kinase B (Akt), and nuclear factor (NF)-κB signaling pathways. Pharmacological inhibitor studies indicated roles for PI 3-kinase/Akt and NF-κB pathways in mediating IL-1β expression, and for NF-κB and p38 MAPK pathways in mediating TNF-α expression. IL-1α-induced IL-6 mRNA expression was reduced by p38 MAPK inhibition, but increased by ERK and JNK pathway inhibitors. IL-10 produced a consistent but modest reduction in IL-1α-induced IL-6 mRNA levels (not IL-1β or TNF-α), but this was not reflected by reduced IL-6 protein secretion. In conclusion, IL-1α stimulates human CMF to express IL-1β, TNF-α, and IL-6 via specific signaling pathways, responses that are unaffected by IL-10 exposure.
N-acetylcysteine inhibits alveolar epithelial-mesenchymal transition
Authors: Felton V. M. , Borok Z. , Willis B. C.
Published: August 2009

The ability of transforming growth factor-β1 (TGF-β1) to induce epithelial-mesenchymal transition (EMT) in alveolar epithelial cells (AEC) in vitro and in vivo, together with the demonstration of EMT in biopsies of idiopathic pulmonary fibrosis (IPF) patients, suggests a role for TGF-β1-induced EMT in disease pathogenesis. We investigated the effects of N-acetylcysteine (NAC) on TGF-β1-induced EMT in a rat epithelial cell line (RLE-6TN) and in primary rat alveolar epithelial cells (AEC). RLE-6TN cells exposed to TGF-β1 for 5 days underwent EMT as evidenced by acquisition of a fibroblast-like morphology, downregulation of the epithelial-specific protein zonula occludens-1, and induction of the mesenchymal-specific proteins α-smooth muscle actin (α-SMA) and vimentin. These changes were inhibited by NAC, which also prevented Smad3 phosphorylation. Similarly, primary alveolar epithelial type II cells exposed to TGF-β1 also underwent EMT that was prevented by NAC. TGF-β1 decreased cellular GSH levels by 50–80%, whereas NAC restored them to ∼150% of those found in TGF-β1-treated cells. Treatment with glutathione monoethyl ester similarly prevented an increase in mesenchymal marker expression. Consistent with its role as an antioxidant and cellular redox stabilizer, NAC dramatically reduced intracellular reactive oxygen species production in the presence of TGF-β1. Finally, inhibition of intracellular ROS generation during TGF-β1 treatment prevented alveolar EMT, but treatment with H2O2alone did not induce EMT. We conclude that NAC prevents EMT in AEC in vitro, at least in part through replenishment of intracellular GSH stores and limitation of TGF-β1-induced intracellular ROS generation. We speculate that beneficial effects of NAC on pulmonary function in IPF may be mediated by inhibitory effects on alveolar EMT.
Neutrophil-mediated lung permeability and host defense proteins
Authors: Kantrow Stephen P. , Shen Zhiwei , Jagneaux Tonya , Zhang Ping , Nelson Steve
Published: August 2009

Neutrophil recruitment to the alveolar space is associated with increased epithelial permeability. The present study investigated in mice whether neutrophil recruitment to the lung leads to accumulation of plasma-derived host defense proteins in the alveolar space and whether respiratory burst contributes to this increase in permeability. Albumin, complement C1q, and IgM were increased in bronchoalveolar lavage (BAL) fluid 6 h after intratracheal LPS challenge. Neutrophil depletion before LPS treatment completely prevented this increase in BAL fluid protein concentration. Respiratory burst was not detected in neutrophils isolated from BAL fluid, and BAL proteins were increased in mice deficient in a key subunit of the respiratory burst apparatus, gp91phox, similar to wild-type mice. Neutrophil recruitment elicited by intratracheal instillation of the chemokines macrophage inflammatory protein-2 and keratinocyte-derived chemokine was also accompanied by accumulation of albumin, C1q, and IgM. During neutrophil recruitment to the alveolar space, epithelial permeability facilitates delivery of host defense proteins. The observed increase in epithelial permeability requires recruitment of neutrophils, but not activation of the respiratory burst, and occurs with chemokine-induced neutrophil migration independent of LPS exposure.
Golgi, trafficking, and mitosis dysfunctions in pulmonary arterial endothelial cells exposed to monocrotaline pyrrole and NO scavenging
Authors: Lee Jason , Reich Reuben , Xu Fang , Sehgal Pravin B.
Published: August 2009

Although the administration of monocrotaline (MCT) into experimental animals is in widespread use today in investigations of pulmonary arterial hypertension (PAH), the underlying cellular and subcellular mechanisms that culminate in vascular remodeling are incompletely understood. Bovine pulmonary arterial endothelial cells (PAECs) in culture exposed to monocrotaline pyrrole (MCTP) develop “megalocytosis” 18–24 h later characterized by enlarged hyperploid cells with enlarged Golgi, mislocalization of endothelial nitric oxide synthase away from the plasma membrane, decreased cell-surface/caveolar nitric oxide (NO), and hypo- S-nitrosylation of caveolin-1, clathrin heavy chain, and N-ethylmaleimide-sensitive factor. We investigated whether MCTP did in fact affect functional intracellular trafficking. The NO scavenger (4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide (c-PTIO) and the NO donor diethylamine NONOate were used for comparison. Both MCTP and c-PTIO produced distinctive four- to fivefold enlarged PAECs within 24–48 h with markedly enlarged/dispersed Golgi, as visualized by immunostaining for the Golgi tethers/matrix proteins giantin, GM130, and p115. Live-cell uptake of the Golgi marker C5ceramide revealed a compact juxtanuclear Golgi in untreated PAECs, brightly labeled enlarged circumnuclear Golgi after MCTP, but minimally labeled Golgi elements after c-PTIO. These Golgi changes were reduced by NONOate. After an initial inhibition during the first day, both MCTP and c-PTIO markedly enhanced anterograde secretion of soluble cargo (exogenous vector-expressed recombinant horseradish peroxidase) over the next 4 days. Live-cell internalization assays using fluorescently tagged ligands showed that both MCTP and c-PTIO inhibited the retrograde uptake of acetylated low-density lipoprotein, transferrin, and cholera toxin B. Moreover, MCTP, and to a variable extent c-PTIO, reduced the cell-surface density of all receptors assayed (LDLR, TfnR, BMPR, Tie-2, and PECAM-1/CD31). In an important distinction, c-PTIO enhanced mitosis in PAECs but MCTP inhibited mitosis, even that due to c-PTIO, despite markedly exaggerated Golgi dispersal. Taken together, these data define a broad-spectrum Golgi and subcellular trafficking dysfunction syndrome in endothelial cells exposed to MCTP or NO scavenging.
Golgi dysfunction is a common feature in idiopathic human pulmonary hypertension and vascular lesions in SHIV-nef-infected macaques
Authors: Sehgal Pravin B. , Mukhopadhyay Somshuvra , Patel Kirit , Xu Fang , Almodóvar Sharilyn , Tuder Rubin M. , Flores Sonia C.
Published: August 2009

Golgi dysfunction has been previously investigated as a mechanism involved in monocrotaline-induced pulmonary hypertension (PAH). In the present study, we addressed whether Golgi dysfunction might occur in pulmonary vascular cells in idiopathic PAH (IPAH) and whether there might be a causal relationship between trafficking dysfunction and vasculopathies of PAH. Quantitative immunostaining for the Golgi tethers giantin and p115 on human lung tissue from patients with IPAH ( n = 6) compared with controls demonstrated a marked cytoplasmic dispersal of giantin- and p115-bearing vesicular elements in vascular cells in the proliferative, obliterative, and plexiform lesions in IPAH and an increase in the amounts of these Golgi tethers/matrix proteins per cell. The causality question was approached by genetic means using human immunodeficiency virus (HIV)-Nef, a protein that disrupts endocytic and trans-Golgi trafficking. Macaques infected with a chimeric simian immunodeficiency virus (SIV) containing the HIV- nef gene (SHIV- nef), but not the nonchimeric SIV virus containing the endogenous SIV- nef gene, displayed pulmonary arterial vasculopathies similar to those in human IPAH. Giantin and p115 levels and their subcellular distribution in pulmonary vascular cells in lungs of SHIV- nef infected macaques ( n = 4) were compared with SIV-infected ( n = 3) and an uninfected macaque control. Only macaques infected with chimeric SHIV- nef showed pulmonary vascular lesions containing cells with dramatic cytoplasmic dispersal and an increase in giantin and p115. Specifically, the HIV-Nef-positive cells showed increased giantin, p115, and the activated transcription factor PY-STAT3. These data represent the first test of the Golgi dysfunction hypothesis in IPAH and place trafficking and Golgi disruption in the chain of causality of pulmonary vasculopathies in the macaque model.
The effects of repeated allergen challenge on airway smooth muscle structural and molecular remodeling in a rat model of allergic asthma
Authors: Labonté Isabelle , Hassan Muhannad , Risse Paul-André , Tsuchiya Kimitake , Laviolette Michel , Lauzon Anne-Marie , Martin James G.
Published: August 2009

The effects of remodeling of airway smooth muscle (SM) by hyperplasia on airway SM contractility in vivo are poorly explored. The aim of this study was to investigate the relationship between allergen-induced airway SM hyperplasia and its contractile phenotype. Brown Norway rats were sensitized with ovalbumin (OVA) or saline on day 0 and then either OVA-challenged once on day 14 and killed 24 h later or OVA-challenged 3 times (on days 14, 19, and 24) and killed 2 or 7 days later. Changes in SM mass, expression of total myosin, SM myosin heavy chain fast isoform (SM-B) and myosin light chain kinase (MLCK), tracheal contractions ex vivo, and airway responsiveness to methacholine (MCh) in vivo were assessed. One day after a single OVA challenge, the number of SM cells positive for PCNA was greater than for control animals, whereas the SM mass, contractile phenotype, and tracheal contractility were unchanged. Two days after three challenges, SM mass and PCNA immunoreactive cells were increased (3- and 10-fold, respectively; P < 0.05), but airway responsiveness to MCh was unaffected. Lower expression in total myosin, SM-B, and MLCK was observed at the mRNA level ( P < 0.05), and total myosin and MLCK expression were lower at the protein level ( P < 0.05) after normalization for SM mass. Normalized tracheal SM force generation was also significantly lower 2 days after repeated challenges ( P < 0.05). Seven days after repeated challenges, features of remodeling were restored toward control levels. Allergen-induced hyperplasia of SM cells was associated with a loss of contractile phenotype, which was offset by the increase in mass.
TNFα inhibits apoptotic cell clearance in the lung, exacerbating acute inflammation
Authors: Borges Valeria M. , Vandivier R. William , McPhillips Kathleen A. , Kench Jennifer A. , Morimoto Konosuke , Groshong Steve D. , Richens Tiffany R. , Graham Brian B. , Muldrow Alaina M. , Heule Lea Van , Henson Peter M. , Janssen William J.
Published: August 2009

Efficient removal of apoptotic cells is essential for resolution of inflammation. Failure to clear dying cells can exacerbate lung injury and lead to persistent inflammation and autoimmunity. Here we show that TNFα blocks apoptotic cell clearance by alveolar macrophages and leads to proinflammatory responses in the lung. Compared with mice treated with intratracheal TNFα or exogenous apoptotic cells, mice treated with the combination of TNFα plus apoptotic cells demonstrated reduced apoptotic cell clearance from the lungs and increased recruitment of inflammatory leukocytes to the air spaces. Treatment with intratracheal TNFα had no effect on the removal of exogenous apoptotic cells from the lungs of TNFα receptor-1 (p55) and -2 (p75) double mutant mice and no effect on leukocyte recruitment. Bronchoalveolar lavage from mice treated with TNFα plus apoptotic cells contained increased levels of proinflammatory cytokines IL-6, KC, and MCP-1, but exhibited no change in levels of anti-inflammatory cytokines IL-10 and TGF-β. Administration of TNFα plus apoptotic cells during LPS-induced lung injury augmented neutrophil accumulation and proinflammatory cytokine production. These findings suggest that the presence of TNFα in the lung can alter the response of phagocytes to apoptotic cells leading to inflammatory cell recruitment and proinflammatory mediator production.
Thrombin induces fibronectin-specific migration of pulmonary microvascular endothelial cells: requirement of calcium/calmodulin-dependent protein kinase II
Authors: Meoli David F. , White R. James
Published: August 2009

Pulmonary arterial hypertension (PAH) is a progressive disease of excess vasoconstriction and vascular cell proliferation that results in increased pulmonary vascular resistance and right heart failure. We have previously shown ( 66 ) that tissue factor expression is increased in the abnormal vessels of patients and rats with PAH. We hypothesized that tissue factor and its downstream mediator, thrombin, would promote migration of endothelial cells (EC) and the vascular pathology of PAH. Immunostaining revealed EC and a fibronectin-enriched matrix within the “plexiform-like” lesions in a rat model of severe PAH. In a modified Boyden assay, protease-activated receptor 1 (PAR1; thrombin receptor) stimulation by agonist peptide or thrombin induced pulmonary microvascular EC (PMVEC) migration when the cells were interacting with fibronectin, but not with other extracellular matrix proteins. Thrombin/fibronectin-induced migration was confirmed in wound healing and angiogenesis assays and was abrogated by the PAR1 antagonist SCH79797 and soluble RGD peptide. This fibronectin dependence was unique to PAR1 activation; other EC agonists evaluated did not induce migration on any matrix, and 10% FBS stimulated similar levels of migration on all matrix proteins tested. Thrombin/fibronectin stimulated autophosphorylation of calcium/calmodulin dependent protein kinase II (CaMKII) in PMVEC, and inhibitors of CaMKII blocked thrombin-induced migration on fibronectin, but had no effect on migration induced by 10% FBS. In contrast, EC isolated from the proximal pulmonary artery migrated in response to most agonists independent of the matrix substrate. Our findings illustrate EC heterogeneity in a single tissue and indicate a novel role for CaMKII in mediating EC migration. Because PMVEC have been shown to have impressive proliferative potential, thrombin/fibronectin-stimulated migration of these cells to a site of injured endothelium is a potential mechanism by which thrombin contributes to the development of vascular lesions in PAH.
Calcineurin plays a modulatory role in loading-induced regulation of type I myosin heavy chain gene expression in slow skeletal muscle
Authors: Pandorf Clay E. , Jiang Weihua H. , Qin Anqi X. , Bodell Paul W. , Baldwin Kenneth M. , Haddad Fadia
Published: August 2009

The role of calcineurin (Cn) in skeletal muscle fiber-type expression has been a subject of great interest because of reports indicating that it controls the slow muscle phenotype. To delineate the role of Cn in phenotype remodeling, particularly its role in driving expression of the type I myosin heavy chain (MHC) gene, we used a novel strategy whereby a profound transition from fast to slow fiber type is induced and examined in the absence and presence of cyclosporin A (CsA), a Cn inhibitor. To induce the fast-to-slow transition, we first subjected rats to 7 days of hindlimb suspension (HS) + thyroid hormone [triiodothyronine (T3)] to suppress nearly all expression of type I MHC mRNA in the soleus muscle. HS + T3 was then withdrawn, and rats resumed normal ambulation and thyroid state, during which vehicle or CsA (30 mg·kg−1·day−1) was administered for 7 or 14 days. The findings demonstrate that, despite significant inhibition of Cn, pre-mRNA, mRNA, and protein abundance of type I MHC increased markedly during reloading relative to HS + T3 ( P < 0.05). Type I MHC expression was, however, attenuated by CsA compared with vehicle treatment. In addition, type IIa and IIx MHC pre-mRNA, mRNA, and relative protein levels were increased in Cn-treated compared with vehicle-treated rats. These findings indicate that Cn has a modulatory role in MHC transcription, rather than a role as a primary regulator of slow MHC gene expression.
Triple Positive Solutions for Third‐Order m‐Point Boundary Value Problems on Time Scales
Authors: Liu Jian , Xu Fuyi
Published: August 2009

We study the following third‐order m‐point boundary value problems on time scales , t ∈ [0, T] T, , uΔ(T) = 0, , where φ : R → R is an increasing homeomorphism and homomorphism and φ(0) = 0, 0 < ξ1 < ⋯<ξm−2 < ρ(T). We obtain the existence of three positive solutions by using fixed‐point theorem in cones. The conclusions in this paper essentially extend and improve the known results.
Diagnosis of Infections Caused by Pathogenic Free-Living Amoebae
Authors: da Rocha-Azevedo Bruno , Tanowitz Herbert B. , Marciano-Cabral Francine
Published: August 2009

Naegleria fowleri,Acanthamoeba spp.,Balamuthia mandrillaris, andSappiniasp. are pathogenic free-living amoebae.N. fowlericauses Primary Amoebic Meningoencephalitis, a rapidly fatal disease of the central nervous system, whileAcanthamoeba spp.andB. mandrillariscause chronic granulomatous encephalitis.Acanthamoeba spp.also can cause cutaneous lesions and Amoebic Keratitis, a sight-threatening infection of the cornea that is associated with contact lens use or corneal trauma.Sappinia pedatahas been identified as the cause of a nonlethal case of amoebic encephalitis. In view of the potential health consequences due to infection with these amoebae, rapid diagnosis is critical for early treatment. Microscopic examination and culture of biopsy specimens, cerebral spinal fluid (CSF), and corneal scrapings have been used in the clinical laboratory. For amoebic keratitis, confocal microscopy has been used to successfully identify amoebae in corneal tissue. More recently, conventional and real-time PCR assays have been developed that are sensitive and specific for the amoebae. In addition, multiplex PCR assays are available for the rapid identification of these pathogens in biopsy tissue, CSF, and corneal specimens.
Ankylosing Spondylitis Patients Commencing Biologic Therapy Have High Baseline Levels of Comorbidity: A Report from the Australian Rheumatology Association Database
Authors: Oldroyd John , Schachna Lionel , Buchbinder Rachelle , Staples Margaret , Murphy Bridie , Bond Molly , Briggs Andrew , Lassere Marissa , March Lyn
Published: August 2009

Aims. To compare the baseline characteristics of a population-based cohort of patients with ankylosing spondylitis (AS) commencing biological therapy to the reported characteristics of bDMARD randomised controlled trials (RCTs) participants.Methods. Descriptive analysis of AS participants in the Australian Rheumatology Association Database (ARAD) who were commencing bDMARD therapy.Results. Up to December 2008, 389 patients with AS were enrolled in ARAD. 354 (91.0%) had taken bDMARDs at some time, and 198 (55.9%) completed their entry questionnaire prior to or within 6 months of commencing bDMARDs. 131 (66.1%) had at least one comorbid condition, and 24 (6.8%) had a previous malignancy (15 nonmelanoma skin, 4 melanoma, 2 prostate, 1 breast, cervix, and bowel). Compared with RCT participants, ARAD participants were older, had longer disease duration and higher baseline disease activity.Conclusions. AS patients commencing bDMARDs in routine care are significantly different to RCT participants and have significant baseline comorbidities.