bluuebunny/crossref_metadata_2025 huggingface dataset:
Uncovering the blind spot of patient satisfaction: an international survey
Authors: Rozenblum Ronen , Lisby Marianne , Hockey Peter M , Levtizion-Korach Osnat , Salzberg Claudia A , Lipsitz Stuart , Bates David W
Published: September 2011

Background

To achieve a high level of patient satisfaction, providers need to identify and address patients' expectations. However, providers' beliefs and attitudes regarding expectations, as well as how to manage them, are not well understood.

Methods

The authors developed a survey to assess clinicians' awareness, attitudes, competence and performance with respect to patient expectations. The authors surveyed clinicians in four academic hospitals located in Denmark, Israel, the UK and the USA.

Results

The authors collected 1004 questionnaires (79.9% response rate) from four hospitals in four countries spanning three continents. Overall, 88.8% of respondents stated that clinician awareness regarding patient expectations was moderate to low, with significant differences between countries (p<0.001). Although 89.4% of clinicians believed it was important to ask patients about expectations, only 16.1% reported actually asking (p<0.0001). Nurses were more likely than physicians to ask patients about expectations (20.1% vs 11.5%, p<0.001). Only 19.6% of respondents felt they had adequate training to handle patients' expectations. In multivariate analyses, clinicians with greater awareness and adequate training were more likely to ask patients about their expectations.

Conclusion

While clinicians think it is important to ask patients about their expectations, they often fail to do so and consequently may not respond adequately. These results identify a ‘blind spot’ in clinicians' approach when attempting to address patient expectations and improve patient satisfaction, suggesting that healthcare organisations should take a more active role in increasing clinicians' awareness and initiating structured training programmes to cope with patient expectations.
The prognostic value of tissue oxygen saturation in emergency department patients with severe sepsis or septic shock
Authors: Vorwerk Christiane , Coats Timothy J
Published: September 2011

Objectives

To determine the derangement of muscle tissue oxygen saturation (StO2) in the early phase of emergency department (ED) sepsis management and its relationship to 30-day mortality in patients with severe sepsis or septic shock.

Methods

A prospective cohort study conducted in the ED of a university hospital. Patients were included if they had a clinical diagnosis of severe sepsis or septic shock. Thenar muscle tissue StO2on arrival in the ED and its change with usual ED sepsis management was measured using near-infrared spectroscopy. A follow-up measurement was obtained after 24 h of treatment. All patients were followed for 30 days.

Results

49 patients were included, of which 24 (49%) died. There was no difference in mean StO2on arrival in the ED between survivors and non-survivors (72% vs 72%; p=0.97). Following ED treatment the mean StO2of survivors improved significantly to 78% (p<0.05) while StO2remained persistently low in non-survivors (p=0.94). Persistently low StO2(<75%) despite initial resuscitative treatment was associated with a twofold increase in mortality (RR of death 2.1%; 95% CI 1.2% to 3.5%).

Conclusion

Patients with severe sepsis/septic shock have abnormal muscle tissue StO2upon arrival in the ED. Inability to normalise StO2with ED sepsis management is associated with a poor outcome. The role of StO2as an early prognostic and potential therapeutic biomarker in severe sepsis or septic shock warrants further exploration.
The generalized second law in chameleon cosmology
Authors: Farajollahi H. , Salehi A. , Tayebi F.
Published: September 2011

In this paper, we investigate the validity of the generalized second law of thermodynamics in flat Friedmann–Lemaître–Robertson–Walker chameleon cosmology where the boundary of the universe is assumed to be enclosed by the dynamical apparent horizon. It has been shown that, in a bouncing scenario for the universe with phantom crossing, the total entropy decreases with time in the contracting epoch, whereas, the dynamics of the internal and horizon entropies depend on the behaviour of both the equation of state and the Hubble parameters.
Impact of α-lipoic acid on liver peroxisome proliferator-activated receptor-α, vascular remodeling, and oxidative stress in insulin-resistant rats
Authors: El Midaoui Adil , Lungu Calin , Wang Hui , Wu Lingyun , Robillard Caroline , DeBlois Denis , Couture Réjean
Published: September 2011

This study sought to determine the impact of α-lipoic acid (LA) on superoxide anion (O2•–) production and peroxisome proliferator-activated receptor-α (PPARα) expression in liver tissue, plasma free fatty acids (FFA), and aortic remodeling in a rat model of insulin resistance. Sprague–Dawley rats (50–75 g) were given either tap water or a drinking solution containing 10% D-glucose for 14 weeks, combined with a diet with or without LA supplement. O2•– production was measured by lucigenin chemiluminescence, and PPAR-α expression by Western blotting. Cross-sectional area (CSA) of the aortic media and lumen and number of smooth muscle cells (SMC) were determined histologically. Glucose increased systolic blood pressure (SBP), plasma levels of glucose and insulin, and insulin resistance (HOMA index). All of these effects were attenuated by LA. Whereas glucose had no effect on liver PPAR-α protein level, it decreased plasma FFA. LA decreased the aortic and liver O2•– production, body weight, and plasma FFA levels in control and glucose-treated rats. Liver PPAR-α protein levels were increased by LA, and negatively correlated with plasma FFA. Medial CSA was reduced in all glucose-treated rats, and positively correlated with plasma FFA but not with SBP or aortic O2•– production. Glucose also reduced aortic lumen area, so that the media-to-lumen ratio remained unchanged. The ability of LA to lower plasma FFA appears to be mediated, in part, by increased hepatic PPAR-α expression, which may positively affect insulin resistance. Glucose-fed rats may serve as a unique model of aortic atrophic remodeling in hypertension and early metabolic syndrome.
Time course of acute neuroprotective effects of lithium carbonate evaluated by brain impedanciometry in the global ischemia model
Authors: Wix-Ramos R. , Eblen-Zajjur A.
Published: September 2011

It is well known that chronic treatment with lithium gives cytoprotection from ischemia and neurodegeneration. Despite the clinical relevance, the potential effects of acute lithium treatment just before and during early stages of ischemia are not well known. Brain impedance was measured in an experimental global ischemia model, to determine these potential effects and their time course,as measured in minutes. Thiobarbital anesthetized (60 mg·kg–1, intraperitoneal injection) male Sprague–Dawley rats were infused intravenously (i.v.) with isovolumetric amounts of ringer (n = 10 rats) or lithium (Li2CO3; 10; 30; 100 mg·kg–1; n = 6 rats per dose tested). Cortico-subcortical impedance was recorded before (20 min) and after (20 min) the infusion, and during global cerebral ischemia (20 min) induced by cardiopulmonary arrest due to the administration of D-tubocurarine. Lithium did not change tissue impedance in normoxid animals. In the ringer-infused group, global cerebral ischemia first (9 min) shows a fast voltage decay rate (–7.08%·min–1), followed by a slow one (–0.94%·min–1) for the last 11 min of the recording. Lithium, at any dose tested, induced a strong reduction in voltage decay for both fast (–3.7%·min–1) and slow (–5.2%·min–1) phases, although the reduction was more intense in the first phase (>58%, Mann–Whitney Z = 2.02; P < 0.043). The reduction was more effective at 10 mg (Li2CO3)·kg–1 than at 30 or 100 mg·kg–1. The time course of brain edema was defined by curve fitting for ringer- (time constant λ = 512.9 s) or lithium-infused animals (λ = 302.0 s). These results suggest that acute lithium infusion 20 min prior to global ischemia, strongly reduces cerebral impedance by reducing the decay rate and the duration of the fast decay phase, and increasing time constant decay during ischemia.
SUBFACTOR REALIZATION OF MODULAR INVARIANTS: II
Authors: EVANS DAVID E. , PINTO PAULO R.
Published: September 2011

We use the subfactor approach to study in detail the realization of the modular invariants of the double of the symmetric group S3at all twists w ∈ Z3(S3, 𝕋) and of the Haagerup subfactor, correcting an error in our previous work.
Caffeine modulates phosphorylation of insulin receptor substrate-1 and impairs insulin signal transduction in rat skeletal muscle
Authors: Egawa Tatsuro , Tsuda Satoshi , Ma Xiao , Hamada Taku , Hayashi Tatsuya
Published: September 2011

Caffeine decreases insulin sensitivity and insulin-stimulated glucose transport in skeletal muscle; however, the precise mechanism responsible for this deleterious effect is not understood fully. We investigated the effects of incubation with caffeine on insulin signaling in rat epitrochlearis muscle. Caffeine (≥1 mM, ≥15 min) suppressed insulin-stimulated insulin receptor substrate (IRS)-1 Tyr612phosphorylation in a dose- and time-dependent manner. These responses were associated with inhibition of the insulin-stimulated phosphorylation of phosphatidylinositol 3-kinase (PI3K) Tyr458, Akt Ser473, and glycogen synthase kinase-3β Ser9and with inhibition of insulin-stimulated 3- O-methyl-d-glucose (3MG) transport but not with inhibition of the phosphorylation of insulin receptor-β Tyr1158/62/63. Furthermore, caffeine enhanced phosphorylation of IRS-1 Ser307and an IRS-1 Ser307kinase, inhibitor-κB kinase (IKK)-α/β Ser176/180. Blockade of IKK/IRS-1 Ser307by caffeic acid ameliorated the caffeine-induced downregulation of IRS-1 Tyr612phosphorylation and 3MG transport. Caffeine also increased the phosphorylation of IRS-1 Ser789and an IRS-1 Ser789kinase, 5′-AMP-activated protein kinase (AMPK). However, inhibition of IRS-1 Ser789and AMPK phosphorylation by dantrolene did not rescue the caffeine-induced downregulation of IRS-1 Tyr612phosphorylation or 3MG transport. In addition, caffeine suppressed the phosphorylation of insulin-stimulated IRS-1 Ser636/639and upstream kinases, including the mammalian target of rapamycin and p70S6 kinase. Intravenous injection of caffeine at a physiological dose (5 mg/kg) in rats inhibited the phosphorylation of insulin-stimulated IRS-1 Tyr612and Akt Ser473in epitrochlearis muscle. Our results indicate that caffeine inhibits insulin signaling partly through the IKK/IRS-1 Ser307pathway, via a Ca2+- and AMPK-independent mechanism in skeletal muscle.
Digital infrared thermographic imaging for remote assessment of traumatic injury
Authors: Cooke William H. , Moralez Gilbert , Barrera Chelsea R. , Cox Paul
Published: September 2011

The purpose of this study was to test the hypotheses that digital infrared thermographic imaging (DITI) during simulated uncontrolled hemorrhage will reveal 1) respiratory rate and 2) changes of skin temperature that track reductions of stroke volume. In 45 healthy volunteers (25 men and 20 women), we recorded the ECG, finger photoplethysmographic arterial pressure, respiratory rate (pneumobelt and DITI of the nose), cardiac output (inert rebreathing), and skin temperature of the forehead during lower body negative pressure (LBNP) at three continuous decompression rates; slow (−3 mmHg/min), medium (−6 mmHg/min), and fast (−12 mmHg/min) to an ending pressure of −60 mmHg. Respiratory rates calculated from the pneumobelt (14.7 ± 0.9 breaths/min) and DITI (14.9 ± 1.2 breaths/min) were not different ( P = 0.21). LBNP induced an average stroke volume reduction of 1.3 ml/mmHg regardless of decompression speed. Maximal reductions of stroke volume and forehead temperature were −100 ± 12 ml and −0.32 ± 0.12°C (slow), −86 ± 12 ml and −0.74 ± 0.27°C (medium), and −78 ± 5 ml and −0.17 ± 0.02°C (fast). Changes of forehead temperature as a function of changes of stroke volume were best described by a quadratic fit to the data (slow R2= 0.95; medium R2= 0.89; and fast R2= 0.99).Our results suggest that a thermographic camera may prove useful for the remote assessment of traumatically injured patients. Life sign detection may be determined by verifying respiratory rate. Determining the magnitude and rate of hemorrhage may also be possible based on future algorithms derived from associations between skin temperature and stroke volume.
Regional function-structure relationships in lungs of an elastase murine model of emphysema
Authors: Ishii Masaru , Emami Kiarash , Xin Yi , Barulic Amy , Kotzer Charles J. , Logan Gregory A. , Chia Elaine , MacDuffie-Woodburn John P. , Zhu Jianliang , Pickup Stephen , Kuzma Nicholas , Kadlecek Stephen , Podolin Patricia L. , Rizi Rahim R.
Published: September 2011

Changes in lung function and structure were studied using hyperpolarized3He MRI in an elastase-induced murine model of emphysema. The combined analysis of the apparent diffusion coefficient (ADC) and fractional ventilation ( R) were used to distinguish emphysematous changes and also to develop a model for classifying sections of the lung into diseased and normal. Twelve healthy male BALB/c mice (26 ± 2 g) were randomized into healthy and elastase-induced mice and studied ∼8–11 wk after model induction. ADC and R were measured at a submillimeter planar resolution. Chord length ( Lx) data were analyzed from histology samples from the corresponding imaged slices. Logistic regression was applied to estimate the probability that an imaged pixel came from a diseased animal, and bootstrap methods (1,000 samples) were used to compare the regression results for the morphological and imaging results. Multivariate ANOVA (MANOVA) was used to analyze transformed ADC (ADCBC), and R ( RBC) data and also to control for the experiment-wide error rate. MANOVA and ANOVA showed that elastase induced a statistically measureable change in the average transformed Lxand ADCBCbut not in the average RBC. Marginal mean analysis demonstrated that ADCBCwas on average 0.19 [95% confidence interval (CI): 0.16, 0.22] higher in the emphysema group, whereas RBCwas on average 0.05 (95% CI: 0.04, 0.06) lower. Logistic regression supported the hypothesis that ADCBCand RBC, together, were better at differentiating normal from diseased tissue than either measurement alone. The odds ratios for ADCBCand RBCwere 7.73 (95% CI: 5.23, 11.42) and 9.14 × 10−5(95% CI: 3.33 × 10−5, 25.06 × 10−5), respectively. Using a 50% probability cutoff, this model classified 70.6% of pixels correctly. The sensitivity and specificity of this model at the 50% cutoff were 74.9% and 65.2%, respectively. The area under the receiver operating characteristic curve was 0.76 (95% CI: 0.74, 0.78). The regression model presented can be used to map MRI data to disease probability maps. These probability maps present a future possibility of using both measurements in a more clinically feasible method of diagnosing this disease.
The Eldercare Factory
Authors: Sharkey Noel , Sharkey Amanda
Published: September 2011

Rapid advances in service robotics together with dramatic shifts in population demographics have led to the notion that technology may be the answer to our eldercare problems. Robots are being developed for feeding, washing, lifting, carrying and mobilising the elderly as well as monitoring their health. They are also being proposed as a substitute for companionship. While these technologies could accrue major benefits for society and empower the elderly, we must balance their use with the ethical costs. These include a potential reduction in human contact, increased feeling of objectification and loss of control, loss of privacy and personal freedom as well as deception and infantilisation. With appropriate guidelines in place before the introduction of robots en masse into the care system, robots could improve the lives of the elderly, reducing their dependence and creating more opportunities for social interaction. Without forethought, the elderly may find themselves in a barren world of machines, a world of automated care: a factory for the elderly.
Fructose Malabsorption: How Much Fructose Can a Healthy Subject Tolerate?
Authors: Frieling T. , Kuhlbusch-Zicklam R. , Kalde S. , Heise J. , Hülsdonk A. , Kreysel C.
Published: September 2011

Background/Aims: In a prospective study, we evaluated fructose absorption capacity in 17 healthy female volunteers aged 16–27 years. Methods: All volunteers underwent analysis of their daily food intake diary and standardized breath tests. The volunteers were challenged consecutively with oral intake of 50, 25 and 15 g of fructose. Results: The average daily ingestion of fructose (19.54 ± 14.95 g) was not different between volunteers with positive and negative breath tests. On day 1, 53% of subjects exhibited a significant (≧20 ppm) increase in breath hydrogen and gastrointestinal symptoms upon challenge with 50 g of fructose. Moreover, 37.5% of the volunteers with a negative breath test became positive upon a second challenge with 50 g of fructose but remained asymptomatic. On day 2, 1 of the 9 volunteers (12.5%) with a positive breath test on day 1 exhibited an asymptomatic positive breath test upon exposure to 25 and 15 g of fructose on day 3. The 8 volunteers with a negative test (25 g of fructose) remained negative after a second exposure to 25 g of fructose. Conclusion: The results of this study indicate that hydrogen breath tests with fructose challenge of 50 g of fructose are inappropriate to characterize clinically significant fructose malabsorption.
Retinoic Acid Rescues Deficient Airway Innervation and Peristalsis of Hypoplastic Rat Lung Explants
Authors: Pederiva Federica , Martinez Leopoldo , Tovar Juan A.
Published: September 2011

Background: Bronchial peristalsis modulates lung growth and is deficient in hypoplastic nitrofen-exposed rat lung explants. Retinoic acid (RA) rescues lung hypoplasia. This study examines whether decreased bronchial innervation contributes to this developmental deficiency and if RA is able to recover bronchial innervation and motility. Material and Methods: After IRB approval, pregnant rats received either 100 mg nitrofen or vehicle on gestational day 9.5 (E9.5). Embryonic lung primordia harvested on E13 were cultured for 72 h and RA was added daily to the medium when appropriate. Lung growth was assessed by counting the number of terminal buds and measuring explant surface, total DNA and protein in control, control + RA, nitrofen and nitrofen + RA groups. Peristaltic contractions were recorded for 10 min under an inverted microscope. Lung explants stained for anti-protein gene product 9.5 (PGP 9.5) and smooth muscle α-actin were examined under a confocal microscope for depicting the specific relationship between neural and smooth muscle cells. PGP 9.5 and smooth muscle α-actin levels were quantified by Western blot analysis for assessing the neural and muscle cell expressions. Comparisons between groups were made with non-parametric tests. Results: The number of terminal buds, the explants’ surface and the DNA and protein contents were significantly decreased in nitrofen-exposed lungs in comparison with controls. In contrast, these measurements were normal in explants exposed to both nitrofen and RA. Bronchial peristalsis (contractions/min) was significantly decreased in nitrofen-exposed lungs in comparison with controls; in contrast, in nitrofen + RA lungs it was similar to controls. In all study groups, the airways were surrounded by smooth muscle and ensheathed in a plexus of nerve fibers containing ganglia. PGP 9.5 protein levels were decreased in nitrofen-exposed lungs, but they normalized when RA was added. No differences were found in α-actin protein levels. Explants exposed only to RA were similar to control. Conclusions: Lung growth, bronchial innervation and peristalsis are decreased in nitrofen-exposed lung explants and are rescued by RA. If deficient airway innervation contributing to dysmotility and pulmonary hypoplasia can be pharmacologically rescued, new relatively simple prenatal interventions could be envisioned.
Determinants of Outcome in Non-Septic Critically Ill Patients with Acute Kidney Injury on Continuous Venovenous Hemofiltration
Authors: Koning Mark V. , Roest Asselina A. , Vervloet Marc G. , Groeneveld A.B. Johan , Nurmohamed Shaikh A.
Published: September 2011

Background/Aims: In view of ongoing controversy, we wished to study whether patient characteristics and/or continuous venovenous hemofiltration (CVVH) characteristics contribute to the outcome of non-septic critically ill patients with acute kidney injury (AKI). Methods: We retrospectively studied 102 consecutive patients in the intensive care unit (ICU) with non-septic AKI needing CVVH. Patient and CVVH characteristics were evaluated. Primary outcome was mortality up to day 28 after CVVH initiation. Results: Forty-four patients (43%) died during the 28-day period after the start of CVVH. In univariate analyses, non-survivors had more often a cardiovascular reason for ICU admission, greater disease acuity/severity and organ failure, lower initial creatinine levels, less use of heparin and more use of bicarbonate-based substitution fluid. The latter two can be attributed to high lactate levels and bleeding tendency in non-survivors necessitating withholding lactate-buffered fluid and heparin, respectively, according to our clinical protocol. In multivariate analyses, mortality was predicted by disease severity, use of bicarbonate-based fluids and lack of heparin, while initial creatinine and CVVH dose did not contribute. Conclusion: The outcome of non-septic AKI in need of CVVH is more likely to be determined by underlying or concurrent, acute and severe disease rather than by CVVH characteristics, including timing and dose.
Passive Exercise Using Whole-Body Periodic Acceleration Enhances Blood Supply to Ischemic Hindlimb
Authors: Rokutanda Taku , Izumiya Yasuhiro , Miura Mitsutoshi , Fukuda Shota , Shimada Kenei , Izumi Yasukatsu , Nakamura Yasuhiro , Araki Satoshi , Hanatani Shinsuke , Matsubara Junichi , Nakamura Taishi , Kataoka Keiichiro , Yasuda Osamu , Kaikita Koichi , Sugiyama Seigo , Kim-Mitsuyama Shokei , Yoshikawa Junichi , Fujita Masatoshi , Yoshiyama Minoru , Ogawa Hisao
Published: September 2011

Objective—

Whole-body periodic acceleration (WBPA) has been developed as a passive exercise technique to improve endothelial function by increasing shear stress through repetitive movements in spinal axis direction. We investigated the effects of WBPA on blood flow recovery in a mouse model of hindlimb ischemia and in patients with peripheral arterial disease.

Methods and Results—

After unilateral femoral artery excision, mice were assigned to either the WBPA (n=15) or the control (n=13) group. WBPA was applied at 150 cpm for 45 minutes under anesthesia once a day. WBPA significantly increased blood flow recovery after ischemic surgery, as determined by laser Doppler perfusion imaging. Sections of ischemic adductor muscle stained with anti-CD31 antibody showed a significant increase in capillary density in WBPA mice compared with control mice. WBPA increased the phosphorylation of endothelial nitric oxide synthase (eNOS) in skeletal muscle. The proangiogenic effect of WBPA on ischemic limb was blunted in eNOS-deficient mice, suggesting that the stimulatory effects of WBPA on revascularization are eNOS dependent. Quantitative real-time polymerase chain reaction analysis showed significant increases in angiogenic growth factor expression in ischemic hindlimb by WBPA. Facilitated blood flow recovery was observed in a mouse model of diabetes despite there being no changes in glucose tolerance and insulin sensitivity. Furthermore, both a single session and 7-day repeated sessions of WBPA significantly improved blood flow in the lower extremity of patients with peripheral arterial disease.

Conclusion—

WBPA increased blood supply to ischemic lower extremities through activation of eNOS signaling and upregulation of proangiogenic growth factor in ischemic skeletal muscle. WBPA is a potentially suitable noninvasive intervention to facilitate therapeutic angiogenesis.
Coupling of Fcγ Receptor I to Fcγ Receptor IIB by Src Kinase Mediates C-Reactive Protein Impairment of Endothelial Function
Authors: Sundgren Nathan C. , Zhu Weifei , Yuhanna Ivan S. , Chambliss Ken L. , Ahmed Mohamed , Tanigaki Keiji , Umetani Michihisa , Mineo Chieko , Shaul Philip W.
Published: September 2011

Rationale:

Elevations in C-reactive protein (CRP) are associated with increased cardiovascular disease risk and endothelial dysfunction. CRP antagonizes endothelial nitric oxide synthase (eNOS) through processes mediated by the IgG receptor Fcγ receptor IIB (FcγRIIB), its immunoreceptor tyrosine-based inhibitory motif, and SH2 domain-containing inositol 5′-phosphatase 1. In mice, CRP actions on eNOS blunt carotid artery re-endothelialization.

Objective:

How CRP activates FcγRIIB in endothelium is not known. We determined the role of Fcγ receptor I (FcγRI) and the basis for coupling of FcγRI to FcγRIIB in endothelium.

Methods and Results:

In cultured endothelial cells, FcγRI-blocking antibodies prevented CRP antagonism of eNOS, and CRP activated Src via FcγRI. CRP-induced increases in FcγRIIB immunoreceptor tyrosine-based inhibitory motif phosphorylation and SH2 domain-containing inositol 5′-phosphatase 1 activation were Src-dependent, and Src inhibition prevented eNOS antagonism by CRP. Similar processes mediated eNOS antagonism by aggregated IgG used to mimic immune complex. Carotid artery re-endothelialization was evaluated in offspring from crosses of CRP transgenic mice (TG-CRP) with either mice lacking the γ subunit of FcγRI (FcRγ
−/−
) or FcγRIIB
−/−
mice. Whereas re-endothelialization was impaired in TG-CRP vs wild-type, it was normal in both FcRγ
−/−
; TG-CRP and FcγRIIB
−/−
; TG-CRP mice.

Conclusions:

CRP antagonism of eNOS is mediated by the coupling of FcγRI to FcγRIIB by Src kinase and resulting activation of SH2 domain-containing inositol 5′-phosphatase 1, and consistent with this mechanism, both FcγRI and FcγRIIB are required for CRP to blunt endothelial repair in vivo. Similar mechanisms underlie eNOS antagonism by immune complex. FcγRI and FcγRIIB may be novel therapeutic targets for preventing endothelial dysfunction in inflammatory or immune complex-mediated conditions.
Neighborhood Disadvantage and Ischemic Stroke
Authors: Brown Arleen F. , Liang Li-Jung , Vassar Stefanie D. , Stein-Merkin Sharon , Longstreth W.T. , Ovbiagele Bruce , Yan Tingjian , Escarce José J.
Published: September 2011

Background and Purpose—

Neighborhood characteristics may influence the risk of stroke and contribute to socioeconomic disparities in stroke incidence. The objectives of this study were to examine the relationship between neighborhood socioeconomic status and incident ischemic stroke and examine potential mediators of these associations.

Methods—

We analyzed data from 3834 whites and 785 blacks enrolled in the Cardiovascular Health Study, a multicenter, population-based, longitudinal study of adults ages ≥65 years from 4 US counties. The primary outcome was adjudicated incident ischemic stroke. Neighborhood socioeconomic status was measured using a composite of 6 census tract variables. Race-stratified multilevel Cox proportional hazard models were constructed adjusted for sociodemographic, behavioral, and biological risk factors.

Results—

Among whites, in models adjusted for sociodemographic characteristics, stroke hazard was significantly higher among residents of neighborhoods in the lowest compared with the highest neighborhood socioeconomic status quartile (hazard ratio, 1.32; 95% CI, 1.01–1.72) with greater attenuation of the hazard ratio after adjustment for biological risk factors (hazard ratio, 1.16; 0.88–1.52) than for behavioral risk factors (hazard ratio, 1.30; 0.99–1.70). Among blacks, we found no significant associations between neighborhood socioeconomic status and ischemic stroke.

Conclusions—

Higher risk of incident ischemic stroke was observed in the most disadvantaged neighborhoods among whites, but not among blacks. The relationship between neighborhood socioeconomic status and stroke among whites appears to be mediated more strongly by biological than behavioral risk factors.
Intracranial Stenting of Subacute Symptomatic Atherosclerotic Occlusion Versus Stenosis
Authors: Lü Peng-Hua , Park Jee Won , Park Soonchan , Kim Jong Lim , Lee Deok Hee , Kwon Sun Uck , Kim Jong Sung , Yun Sung-Cheol , Suh Dae Chul
Published: September 2011

Background and Purpose—

Limited data are available concerning the outcome of angioplasty/stenting for subacute atherosclerotic intracranial artery occlusion, which is often associated with progressive symptom development in the salvageable brain under ischemic threat due to poor collateral blood supply.

Methods—

Among 177 patients who underwent angioplasty and/or stenting for severe symptomatic intracranial steno-occlusion, 26 had subacute atherosclerotic intracranial artery occlusion. Outcome after stenting (N=22) was assessed according to procedural success (return of antegrade flow and residual stenosis <50%), adverse event (any stroke or death) rate, and restenosis (>50%) using weighted Cox proportional hazards regression in the overall cohort and in separate subgroups.

Results—

Successful recanalization was achieved in 95%. Three adverse events (13.6%) occurred among patients undergoing stenting for occlusion, including 2 major strokes and 1 nonprocedure-related death. Good outcome (modified Rankin Scale ≤2) was achieved in 73%. In the overall cohort, no significant difference was observed between the occlusion and stenosis groups in terms of the risk of adverse events (hazard ratio for the occlusion group, 1.055; 95% CI, 0.29–3.90) or the risk of restenosis (hazard ratio for the occlusion group, 1.2; 95% CI, 0.19–7.72). A trend toward a higher rate of adverse events was observed in older age (>65 years), progressive worsening, balloon-expandable stent, and no history of a preprocedural P2Y12 assay.

Conclusions—

In a cohort of patients undergoing angioplasty/stenting for subacute atherosclerotic intracranial artery occlusion, no significant difference in the rates of adverse events was observed. However, several factors, including age, tended to be associated with a higher event rate.
Postcontrast Susceptibility-Weighted Imaging
Authors: Jagadeesan Bharathi D. , Delgado Almandoz Josser E. , Benzinger Tammie L.S. , Moran Christopher J.
Published: September 2011

Background and Purpose—

The purpose of this study was to determine the utility of postcontrast susceptibility-weighted MRI (PCSWI) in the evaluation of vascular malformations of the brain (BVM).

Methods—

We retrospectively evaluated PCSWI and digital subtraction angiography data from 16 consecutive patients with known or suspected BVM, which had been entered into a prospectively maintained database during a 1-year period. There had been no intervening treatment or change in patients' symptoms between the PCSWI and digital subtraction angiography studies. The use of PCSWI in the detection of arteriovenous shunting was compared with that of routine noncontrast susceptibility-weighted imaging, time-of-flight MR angiography, and contrast-enhanced MR angiography using digital subtraction angiography results as the reference standard. The presence of arteriovenous shunting in PCSWI or susceptibility-weighted imaging sequences was defined by the presence of abnormal signal hyperintensity in the venous structures adjacent to the BVM.

Results—

A total of 17 BVMs were identified by digital subtraction angiography (9 newly diagnosed arteriovenous malformations, 3 dural arteriovenous fistulas, 4 treated arteriovenous malformations with residual arteriovenous shunting, and 1 complex developmental venous anomaly). PCSWI was 100% sensitive and 100% specific with 100% positive predictive value and 100% negative predictive value for the detection of arteriovenous shunting in these BVMs. The PCSWI/susceptibility-weighted imaging signal intensity ratio in the most prominent early draining venous structure was 1.2±0.32.

Conclusions—

PCSWI appears to be superior to susceptibility-weighted imaging, time-of-flight MR angiography, and contrast-enhanced MR angiography in detecting arteriovenous shunting in BVMs and may be useful in the initial diagnosis and follow-up of patients with BVMs.
Vertebral Artery Halo Sign in Patients With Stroke
Authors: García-García Jorge , Ayo-Martín Óscar , Argandoña-Palacios Lucía , Segura Tomas
Published: September 2011

Background and Purpose—

The purpose of this study was to describe typical ultrasonographic findings of vertebral arteries in patients affected by giant cell arteritis.

Methods—

Color duplex sonography was used to asses the cervical arteries within 24 hours from stroke onset in 1237 patients. Vertebral arteritis was considered if concentric, homogeneous, and smooth hypoechogenic mural thickening (the so-called halo sign) was present in at least 1 cervical segment of the vertebral artery. If the patient showed such findings, an ultrasound examination of the temporal artery was also performed. Patients with probable giant cell arteritis were treated with high-dose intravenous methylprednisolone in association with antiplatelet therapy. Temporal artery biopsy was carried out by a vascular surgeon in the site targeted by the ultrasonographer.

Results—

Five patients were diagnosed as having vertebral arteritis according to ultrasound criteria. All of them had initial neurological deficit due to infarctions affecting the vertebrobasilar territory. One patient died due to aspiration pneumonia, whereas the others were independent at discharge. All patients had a positive biopsy for giant cell arteritis.

Conclusions—

Vertebral artery involvement in giant cell arteritis may be suspected by color duplex sonography. This fact would allow a prompt diagnosis and treatment of this otherwise fatal disease. Because duplex ultrasonography is a usual test performed on patients with stroke, the recognition of the halo sign in vertebral arteries may be of crucial interest in selected cases.
Telomerase Reverse Transcriptase Upregulation Attenuates Astrocyte Proliferation and Promotes Neuronal Survival in the Hypoxic–Ischemic Rat Brain
Authors: Qu Yi , Duan Zhoujin , Zhao Fengyan , Wei Dapeng , Zhang Jianbo , Tang Binzhi , Li Jiao , Yang Chunlei , Mu Dezhi
Published: September 2011

Background and Purpose—

Telomerase reverse transcriptase (TERT) is tightly related to the resistance of cells to stress and injury. However, little is known about the roles of TERT in the nervous system. We try to investigate the effects of TERT on the function of astrocytes in developing rat brains subjected to hypoxia–ischemia.

Methods—

TERT expression was detected in rat brains with hypoxia–ischemia. In in vitro study, the function of astrocytes with TERT overexpression was measured, and the effects of astrocyte on neuronal apoptosis were examined. Moreover, overexpression or inhibition of TERT was conducted in vivo by gene transduction. Astrocyte proliferation was examined through Ki67 staining. Terminal deoxynucleotidyltransferase-mediated dUTP nick end labeling staining and brain infarct volume calculation were used to detect neuronal injury.

Results—

Both TERT mRNA and protein were upregulated in neurons within 2 days but shifted to astrocytes at Day 3 after hypoxia–ischemia. Astrocyte proliferation was inhibited with TERT overexpression due to the upregulation of cell-cycle regulatory protein p15. Meanwhile, the apoptosis of neurons increased, whereas neurons were cocultured with conditioned media from astrocytes with TERT inhibition compared with TERT overexpression due to the decrease of neurotrophin-3 expression in astrocytes. Furthermore, Ki67-positive astrocytes and neuronal injury were found to be inhibited in TERT-overexpressing rat brains with hypoxia–ischemia.

Conclusions—

TERT attenuates astrocyte proliferation and promotes neuronal survival in the developing rat brain after hypoxia–ischemia, partly through its enhancement of p15 and neurotrophin-3 expression in astrocytes.
Adverse Effects of Bone Marrow Stromal Cell Treatment of Stroke in Diabetic Rats
Authors: Chen Jieli , Ye Xinchun , Yan Tao , Zhang Chunling , Yang Xiao-Ping , Cui Xu , Cui Yishen , Zacharek Alex , Roberts Cynthia , Liu Xinfeng , Dai Xiangguo , Lu Mei , Chopp Michael
Published: September 2011

Background and Purpose—

Cell therapy with bone marrow stromal cells (BMSCs) improves functional recovery after stroke in nondiabetic rats. However, its effect on diabetics with stroke is unknown. This study investigated the effect of BMSCs on stroke outcome in Type 1 diabetic (T1DM) rats.

Methods—

T1DM was induced in adult male Wistar rats by injecting streptozotocin. Nondiabetic and T1DM rats were subjected to 2 hours of middle cerebral artery occlusion (MCAO), treated with or without BMSCs (3×10
6
) at 24 hours after MCAO, and monitored for 14 days.

Results—

Functional benefit was not detected in T1DM-MCAO treated with BMSC rats compared with corresponding T1DM-MCAO controls. BMSC treatment in T1DM-MCAO rats had increased mortality, blood–brain barrier leakage, brain hemorrhage, and angiogenesis. Internal carotid artery neointimal formation and cerebral arteriole narrowing/occlusion were also observed in T1DM-MCAO+BMSCs rats compared with T1DM-MCAO controls (
P
<0.05), but not in nondiabetic stroke rats. We further studied the underlying mechanisms responsible for BMSC-induced blood–brain barrier leakage and accelerated vascular damage in T1DM-MCAO rats. We found that the expression of angiogenin (an angiogenic factor) and ED1 (a marker for macrophages) was significantly increased in the T1DM-MCAO+BMSC rats in the ischemic brain and internal carotid artery compared with nontreated T1DM-MCAO rats, but not in nondiabetic stroke rats.

Conclusions—

BMSC therapy in T1DM-MCAO rats does not improve functional outcome. On the contrary, it increases blood–brain barrier leakage and cerebral artery neointimal formation, and arteriosclerosis, which possibly is due to increased expression of angiogenin. Thus, BMSC treatment starting 24 hours after MCAO may not be beneficial for diabetic subjects with stroke.
Learning Entailment Relations by Global Graph Structure Optimization
Authors: Berant Jonathan , Dagan Ido , Goldberger Jacob
Published: September 2011

Identifying entailment relations between predicates is an important part of applied semantic inference. In this article we propose a global inference algorithm that learns such entailment rules. First, we define a graph structure over predicates that represents entailment relations as directed edges. Then, we use a global transitivity constraint on the graph to learn the optimal set of edges, formulating the optimization problem as an Integer Linear Program. The algorithm is applied in a setting where, given a target concept, the algorithm learns on the fly all entailment rules between predicates that co-occur with this concept. Results show that our global algorithm improves performance over baseline algorithms by more than 10%.
The Global Atmospheric Circulation Response to Tropical Diabatic Heating Associated with the Madden–Julian Oscillation during Northern Winter
Authors: Seo Kyong-Hwan , Son Seok-Woo
Published: September 2011

The detailed dynamical mechanisms of the upper-tropospheric circulation response to the Madden–Julian oscillation (MJO) convection are examined by integrating a primitive equation model. A series of initial-value calculations with the climatological boreal winter background flow forced by the MJO-like thermal forcing successfully capture the key aspects of the observed circulation response to the MJO convection. This suggests that a large fraction of MJO-related circulation anomalies are direct responses to tropical heating in both the tropics and extratropics and can be largely explained by linear dynamics.

It is found that MJO-like dipole heatings not only intensify tropical upper-tropospheric anomalies but also weaken them at certain regions because of the interaction between equatorial Kelvin and Rossby waves. The Rossby wave train primarily excited by horizontal divergence of upper-level perturbation flow propagates northeastward and then heads back to the equator. In this way, Rossby wave activity once generated over the subtropical Indian Ocean tends to enhance the equatorial upper-tropospheric anomalies over the tropical Atlantic and West Africa that have already been created by the zonally propagating equatorial Rossby and Kelvin waves. A ray path tracing reveals that a successive downstream development of Rossby wave train mostly results from the large-scale waves with zonal wavenumbers 2–3 in the Northern Hemisphere and 3–5 in the Southern Hemisphere.

The sensitivity tests show that the overall results are quite robust. It is found, however, that the detailed circulation response to the MJO-like forcing is somewhat sensitive to the background flow. This suggests that MJO-related circulation anomalies may have nonnegligible long-term variability and change as background flow varies.
The Effects and Interactions of Student, Teacher, and Setting Variables on Reading Outcomes for Kindergarteners Receiving Supplemental Reading Intervention
Authors: Hagan-Burke Shanna , Coyne Michael D. , Kwok Oi-man , Simmons Deborah C. , Kim Minjung , Simmons Leslie E. , Skidmore Susan T. , Hernandez Caitlin L. , McSparran Ruby Maureen
Published: September 2011

This exploratory study examined the influences of student, teacher, and setting characteristics on kindergarteners’ early reading outcomes and investigated whether those relations were moderated by type of intervention. Participants included 206 kindergarteners identified as at risk for reading difficulties and randomly assigned to one of two supplemental interventions: (a) an experimental explicit, systematic, code-based program or (b) their schools’ typical kindergarten reading intervention. Results from separate multilevel structural equation models indicated that among student variables, entry-level alphabet knowledge was positively associated with phonemic and decoding outcomes in both conditions. Entry-level rapid automatized naming also positively influenced decoding outcomes in both conditions. However, its effect on phonemic outcomes was statistically significant only among children in the typical practice comparison condition. Regarding teacher variables, the quality of instruction was associated with significantly higher decoding outcomes in the typical reading intervention condition but had no statistically significant influence on phonemic outcomes in either condition. Among setting variables, instruction in smaller group sizes was associated with better phonemic outcomes in the comparison condition but had no statistically significant influence on outcomes of children in the intervention group. Mode of delivery (i.e., pullout vs. in class) had no statistically significant influence on either outcome variable.
Effects of Ovariectomy and Estrogen Replacement Therapy on Laryngeal Tissue
Authors: Tatlıpınar Arzu , Güneş Pembegül , Özbeyli Dilek , Çimen Burak , Gökçeer Tanju
Published: September 2011

Objective

To determine the histopathological effect of estrogen deficiency and hormone replacement treatment on laryngeal tissue in ovariectomized rats.

Study Design

Animal study.

Setting

The study was conducted at the animal experiment laboratory of Marmara University School of Medicine, Istanbul, Turkey.

Subjects and Methods

Six‐month‐old female Wistar albino rats were divided into the following 3 groups (n = 8 per group): sham‐operated control, ovariectomized, and ovariectomized with estrogen replacement. Rats in the ovariectomized with estrogen replacement group received 17 β‐estradiol valerate (200 µg/kg, subcutaneously) once a week. Animals were killed after 8 weeks of intervention.

Results

Significant changes were observed in the ovariectomized group when edema in lamina propria, inflammation in squamous, respiratory epithelia and lamina propria, pseudostratification, and cilia loss were assessed. Except cilia loss, there were no significant differences in the assessments between the sham‐operated control and ovariectomized with estrogen replacement groups.

Conclusions

On the basis of histopathological evaluations, it was shown that estrogen replacement helped to improve laryngeal changes due to experimentally induced menopause.
Acute sleep deprivation: the effects of the AMPAKINE compound CX717 on human cognitive performance, alertness and recovery sleep
Authors: Boyle Julia , Stanley Neil , James Lynette M , Wright Nicola , Johnsen Sigurd , Arbon Emma L , Dijk Derk-Jan
Published: September 2011

AMPA receptor modulation is a potential novel approach to enhance cognitive performance. CX717 is a positive allosteric modulator of the AMPA receptor that has shown efficacy in rodent and primate cognition models. CX717 (100 mg, 300 mg and 1000 mg) and placebo were studied in 16 healthy male volunteers (18–45 years) in a randomized, crossover study. Cognitive function, arousal and recovery sleep (by polysomnography) were assessed during the extended wakefulness protocol. Placebo condition was associated with significant decrements in cognition, particularly at the circadian nadir (between 03:00 and 05:00). Pre-specified primary and secondary analyses (general linear mixed modelling, GLMM) at each separate time point did not reveal consistent improvements in performance or objective alertness with any dose of CX717. Exploratory repeated measures analysis, a method used to take into account the influence of individual differences, demonstrated an improvement in attention-based task performance following the 1000 mg dose. Analysis of the recovery sleep showed that CX717 1000 mg significantly reduced stage 4 and slow-wave sleep ( p ≤ 0.05) with evidence of reduced electroencephalogram (EEG) slow-wave and spindle activity. The study suggests that CX717 only at the 1000 mg dose may counteract effects of sleep deprivation on attention-based tasks and that it may interfere with subsequent recovery sleep.
Girls Gone Wild? Heterosexual Women’s Same-Sex Encounters at College Parties
Authors: Yost Megan R. , McCarthy Lauren
Published: September 2011

Our purpose was to explore a relatively new sexual behavior—heterosexual women kissing one another publicly at college parties. Popular press articles suggest this is a common occurrence among college women, but no known psychological research has been conducted on its prevalence or meaning. In Study 1, we conducted an online survey of students at a private, residential college to ascertain the prevalence of this behavior. Results indicated that a substantial minority of women (33%) had engaged in this behavior, and the majority of participants (69%), both male and female, had observed this behavior. In Study 2, we recruited heterosexual women who reported having kissed another woman at a college party. We collected open-ended responses from 77 women via a questionnaire and 27 of these women also completed a semistructured interview. Thematic analyses revealed characteristics of the social context that encouraged this behavior, including pressure to so engage, high levels of alcohol consumption, heterosexist attitudes, and the belief that college is a time for experimentation. A total of seven different motivations for engaging in this behavior were described by participants, reflecting both extrinsic motivations (e.g., to gain male attention) and intrinsic motivations (e.g., to bond with female friends). Results are discussed in terms of sociocultural influences (women’s sexual objectification and sexualized college parties) and individual factors (women’s sexual fluidity and heterosexual identity development) related to this behavior, highlighting issues of empowerment versus objectification.