bluuebunny/crossref_metadata_2025 huggingface dataset:
Dissociation between cardiomyocyte function and remodeling with β-adrenergic receptor blockade in isolated canine mitral regurgitation
Authors: Pat Betty , Killingsworth Cheryl , Denney Thomas , Zheng Junying , Powell Pamela , Tillson Michael , Dillon A. Ray , Dell'Italia Louis J.
Published: October 2008

The low-pressure volume overload of isolated mitral regurgitation (MR) is associated with increased adrenergic drive, left ventricular (LV) dilatation, and loss of interstitial collagen. We tested the hypothesis that β1-adrenergic receptor blockade (β1-RB) would attenuate LV remodeling after 4 mo of MR in the dog. β1-RB did not attenuate collagen loss or the increase in LV mass in MR dogs. Using MRI and three-dimensional (3-D) analysis, there was a 70% increase in the LV end-diastolic (LVED) volume-to-LV mass ratio, a 23% decrease in LVED midwall circumferential curvature, and a >50% increase in LVED 3-D radius/wall thickness in MR dogs that was not attenuated by β1-RB. However, β1-RB caused a significant increase in LVED length from the base to apex compared with untreated MR dogs. This was associated with an increase in isolated cardiomyocyte length (171 ± 5 μm, P < 0.05) compared with normal (156 ± 3 μm) and MR (165 ± 4 μm) dogs. Isolated cardiomyocyte fractional shortening was significantly depressed in MR dogs compared with normal dogs (3.73 ± 0.31 vs. 5.02 ± 0.26%, P < 0.05) and normalized with β1-RB (4.73 ± 0.48%). In addition, stimulation with the β-adrenergic receptor agonist isoproterenol (25 nM) increased cardiomyocyte fractional shortening by 215% ( P < 0.05) in β1-RB dogs compared with normal (56%) and MR (50%) dogs. In summary, β1-RB improved LV cardiomyocyte function and β-adrenergic receptor responsiveness despite further cell elongation. The failure to attenuate LV remodeling associated with MR could be due to a failure to improve ultrastructural changes in extracellular matrix organization.
A further analysis of why pulmonary venous pressure rises after the onset of LV dysfunction
Authors: Magder S. , Veerassamy S. , Bates J. H. T.
Published: October 2008

Based on a dynamic computational model of the circulation, Burkhoff and Tyberg ( Am J Physiol Heart Circ Physiol 265: H1819–H1828, 1993) concluded that the rise in pulmonary venous pressure (Pvp) with left ventricular (LV) dysfunction requires a decrease in vascular capacitance and transfer of unstressed volume to stressed volume (ν). We argue that the values they used for venous resistance (Rvs), venous compliance (Cvs), and ν were too low, and changing these values significantly changes the conclusion. We used a computational model of the circulation that was similar to theirs, but we made Rvs four times higher (0.06 versus 0.015 mmHg·s·ml−1), Cvs larger (110 versus 70 ml/mmHg), and ν larger (1,400 versus 750 ml); all other parameters, including those for the heart, were essentially the same. We simulated left ventricular dysfunction by decreasing end-systolic elastance (Eeslv) as they did and examined changes in cardiac output, arterial blood pressure, and Pvp. We then examined the effect of changes in Rvs, heart rate, and ν when Eeslv was depressed with and without pericardial constraint. In contrast to their findings, with our parameters the model predicts that decreasing Eeslv substantially increases Pvp. Furthermore, increasing systemic vascular resistance or decreasing Rvs or heart rate produces large increases in Pvp when Eeslv is reduced. Pericardial constraint limits the changes in Pvp. In conclusion, when Rvs and Cvs are increased, baseline ν must be higher to maintain normal cardiac output. This increased volume can shift between compartments under flow conditions and account for the increase in Pvp with decreased left ventricular function even without recruitment of unstressed volume.
Altered collagen fiber kinematics define the onset of localized ligament damage during loading
Authors: Quinn Kyle P. , Winkelstein Beth A.
Published: October 2008

Detecting the initiation of mechanical injury to biological tissue, and not just its ultimate failure, is critical to a sensitive and specific characterization of tissue tolerance, development of quantitative relationships between macro- and microstructural tissue responses, and appropriate interpretation of physiological responses to loading. We have developed a novel methodological approach to detect the onset and spatial location of structural damage in collagenous soft tissue, before its visible rupture, via identification of atypical regional collagen fiber kinematics during loading. Our methods utilize high-speed quantitative polarized light imaging to identify the onset of tissue damage in ligament regions where mean collagen fiber rotation significantly deviates from its behavior during noninjurious loading. This technique was validated by its ability to predict the location of visible rupture ( P = 0.0009). This fiber rotation-based metric of damage identifies potential facet capsular ligament injury beginning well before rupture, at 51 ± 12% of the displacement required to produce tissue failure. Although traditional macroscale strain metrics fail to identify the location of microstructural damage, initial injury detection determined by altered fiber rotation was significantly correlated ( R = 0.757, P = 0.049) with tissue yield (defined by a decrease in stiffness), supporting the capabilities of this method. Damaged regions exhibited higher variance in fiber direction than undamaged regions ( P = 0.0412).
Individualization of transfer function in estimation of central aortic pressure from the peripheral pulse is not required in patients at rest
Authors: Westerhof Berend E. , Guelen Ilja , Stok Wim J. , Lasance Han A. J. , Ascoop Carl A. P. L. , Wesseling Karel H. , Westerhof Nico , Bos Willem Jan W. , Stergiopulos Nikos , Spaan Jos A. E.
Published: October 2008

Central aortic pressure gives better insight into ventriculo-arterial coupling and better prognosis of cardiovascular complications than peripheral pressures. Therefore transfer functions (TF), reconstructing aortic pressure from peripheral pressures, are of great interest. Generalized TFs (GTF) give useful results, especially in larger study populations, but detailed information on aortic pressure might be improved by individualization of the TF. We found earlier that the time delay, representing the travel time of the pressure wave between measurement site and aorta is the main determinant of the TF. Therefore, we hypothesized that the TF might be individualized (ITF) using this time delay. In a group of 50 patients at rest, aged 28–66 yr (43 men), undergoing diagnostic angiography, ascending aortic pressure was 119 ± 20/70 ± 9 mmHg (systolic/diastolic). Brachial pressure, almost simultaneously measured using catheter pullback, was 131 ± 18/67 ± 9 mmHg. We obtained brachial-to-aorta ITFs using time delays optimized for the individual and a GTF using averaged delay. With the use of ITFs, reconstructed aortic pressure was 121 ± 19/69 ± 9 mmHg and the root mean square error (RMSE), as measure of difference in wave shape, was 4.1 ± 2.0 mmHg. With the use of the GTF, reconstructed pressure was 122 ± 19/69 ± 9 mmHg and RMSE 4.4 ± 2.0 mmHg. The augmentation index (AI) of the measured aortic pressure was 26 ± 13%, and with ITF and GTF the AIs were 28 ± 12% and 30 ± 11%, respectively. Details of the wave shape were reproduced slightly better with ITF but not significantly, thus individualization of pressure transfer is not effective in resting patients.
Two faces of nitric oxide: implications for cellular mechanisms of oxygen toxicity
Authors: Allen Barry W. , Demchenko Ivan T. , Piantadosi Claude A.
Published: October 2008

Recent investigations have elucidated some of the diverse roles played by reactive oxygen and nitrogen species in events that lead to oxygen toxicity and defend against it. The focus of this review is on toxic and protective mechanisms in hyperoxia that have been investigated in our laboratories, with an emphasis on interactions of nitric oxide (NO) with other endogenous chemical species and with different physiological systems. It is now emerging from these studies that the anatomical localization of NO release, which depends, in part, on whether the oxygen exposure is normobaric or hyperbaric, strongly influences whether toxicity emerges and what form it takes, for example, acute lung injury, central nervous system excitation, or both. Spatial effects also contribute to differences in the susceptibility of different cells in organs at risk from hyperoxia, especially in the brain and lungs. As additional nodes are identified in this interactive network of toxic and protective responses, future advances may open up the possibility of novel pharmacological interventions to extend both the time and partial pressures of oxygen exposures that can be safely tolerated. The implications of a better understanding of the mechanisms by which NO contributes to central nervous system oxygen toxicity may include new insights into the pathogenesis of seizures of diverse etiologies. Likewise, improved knowledge of NO-based mechanisms of pulmonary oxygen toxicity may enhance our understanding of other types of lung injury associated with oxidative or nitrosative stress.
Ibn al-Nafis, the pulmonary circulation, and the Islamic Golden Age
Authors: West John B.
Published: October 2008

Ibn al-Nafis (1213–1288) was an Arab physician who made several important contributions to the early knowledge of the pulmonary circulation. He was the first person to challenge the long-held contention of the Galen School that blood could pass through the cardiac interventricular septum, and in keeping with this he believed that all the blood that reached the left ventricle passed through the lung. He also stated that there must be small communications or pores ( manafidh in Arabic) between the pulmonary artery and vein, a prediction that preceded by 400 years the discovery of the pulmonary capillaries by Marcello Malpighi. Ibn al-Nafis and another eminent physiologist of the period, Avicenna (ca. 980–1037), belong to the long period between the enormously influential school of Galen in the 2nd century, and the European scientific Renaissance in the 16th century. This is an epoch often given little attention by physiologists but is known to some historians as the Islamic Golden Age. Its importance is briefly discussed here.
Folate Nutritional Genetics and Risk for Hypertension in an Elderly Population Sample
Authors: Ng Xiaowei , Boyd Lyndell , Dufficy Lisa , Naumovski Nenad , Blades Barbara , Travers Cheryl , Lewis Peter , Sturm Jonathon , Yates Zoë , Townley-Jones Maureen , Roach Paul , Veysey Martin , Lucock Mark
Published: October 2008

Background/Aims: 118 elderly participants (65–90 years) were assessed for any relationship between folate, related genes and hypertension. Methods: Six B-vitamin-related SNPs were genotyped in 80 normotensive and 38 hypertensive subjects. Results: Of six polymorphisms (677C>T-MTHFR, 1298A>C-MTHFR, 80G>A-RFC, 2756A>G-MS, 66A>G- MSR, 19bpDHFR and 1561C>T-GCPII), only 677C>T-MTHFR was a significant risk for hypertension: OR 1.89; 95% CI 1.07–3.32 (χ2 p = 0.038). Additionally, hypertensive subjects had a significantly lower intake of dietary folate than normotensive individuals (p = 0.0221), although this did not markedly alter blood metabolite levels. Several significant linear associations between dietary folate and related blood metabolites were found in normotensive subjects (p < 0.001 for Hcy, red cell and serum folate) and were as predicted on an a priori basis – generally weaker associations existed in hypertensive subjects (p < 0.05 for serum folate). This was true for data examined collectively or by genotype. Multiple-regression analysis for diastolic or systolic blood pressure showed significant interaction for gender and folate intake (p = 0.014 and 0.019, respectively). In both cases this interaction occurred only in females, with higher folate intake associated with decreased blood pressure. Regressing diastolic blood pressure and 677C>T-MTHFR genotype showed significance (males; p = 0.032) and borderline significance (all subjects). Conclusion: Dietary folate and 677C>T-MTHFR genotype may modify blood pressure.
Evaluation of Acellular Dermis for Closure of Abdominal Wall Defects in a Rat Model
Authors: Pirayesh A. , Dur A.H.M. , Paauw N.J. , Monstrey S. , Kreis R.W. , Hoekstra M.J. , Richters C.D.
Published: October 2008

Background: Abdominal wall repair can be performed with synthetic or biological materials. Biological materials may reduce the risk of infections and fibrosis. The aim of this study was to evaluate two acellular human dermis products. Materials and Methods: A rat model was used to compare the two materials. One was prepared using low concentrations of NaOH; the other material was SureDerm™, which is commercially available. Full thickness defects were prepared in the abdominal wall and closed with the materials. Rats were sacrificed at 1 or 4 months after operation and the numbers of adhesions to the bowels were scored. Samples were tak- en for histological analysis and to measure the breaking strength. Results: In both groups a good functional integration of the implants with the abdominal wall was observed. There was no adhesion formation with the bowels in the group with the NaOH prototype. In the SureDerm group, 4 out of 7 rats showed only small adhesions at 4 months after operation. Breaking strength of the healed tissue was significantly higher in the NaOH prototype group at 4 months after operation (p < 0.0026). Conclusions: The results indicate that both human acellular dermis products may be used in clinical trials for closure of abdominal wall defects.
Comparison of the Potency of Different Brands of Serenoa Repens Extract on 5α-Reductase Types I and II in Prostatic Co-Cultured Epithelial and Fibroblast Cells
Authors: Scaglione Francesco , Lucini Valeria , Pannacci Marilou , Caronno Alessia , Leone Claude
Published: October 2008

Background:Serenoa repens extract is the phytotherapeutic agent most frequently used for the treatment of the urological symptoms caused by benign prostatic hyperplasia. There are many extracts in the market and each manufacturer uses different extraction processes; for this reason, it’s possible that one product is not equivalent to another. The aim of this study was to compare the activity of different extracts of Serenoa repens marketed in Italy. Methods: The following extracts were tested on 10 day co-cultured epithelial and fibroblast cells by a 5α-reductase activity assay: Permixon®, Saba®, Serpens®, Idiprost®, Prostamev®, Profluss® and Prostil®. In order to assess the variability in Serenoa repens products, 2 different batches for each brand were evaluated. Results and Conclusions: All extracts tested, albeit variably, are able to inhibit both isoforms of 5α-reductase. However, the potency of the extracts appears to be very different, as well as the potencies of 2 different batches of the same extract. This is probably due to qualitative and quantitative differences in the active ingredients. So, the product of each company must be tested to evaluate the clinical efficacy and bioactivity.
Obesity and the Metabolic Syndrome in the Elderly – A Mini-Review
Authors: Lechleitner Monika
Published: October 2008

The metabolic syndrome is defined as a cluster of cardiometabolic risk factors which are related to insulin resistance. Beyond the importance of each separate risk factor, the aggregation of abdominal obesity, impaired glucose metabolism, dyslipidemia and hypertension, summarized as the metabolic syndrome, characterizes individuals with a significant increase in the risk for type 2 diabetes and cardiovascular disease. In the prosperous countries of the world, the prevalence of the metabolic syndrome is about 20% in the adult population, and increases with increasing age, which is mainly attributed to the significant increase in overweight and obesity, also in elderly. Current data indicate that weight-loss therapy improves physical function, quality of life and the medical complications associated with obesity. This review summarizes epidemiologic data, diagnostic criteria and the clinical importance of the metabolic syndrome, the complex pathophysiologic mechanisms involved in the development of insulin resistance in elderly, and the various therapeutic options. According to these data the identification and treatment of patients with a metabolic syndrome would be an important approach to reduce morbidity and impairments in the elderly.
Alcohol and Estrogen Replacement Therapy in Postmenopausal Women
Authors: Tivis Laura J. , Ceballos Natalie A. , Chastain Garvin , Tivis Rick D.
Published: October 2008

The literature remains contentious regarding the separate and combined effects of moderate drinking and estrogen replacement therapy (ERT) on cognition. In the current study, the authors sought to disentangle the predictive utility of alcohol use, ERT and their interaction on the episodic and semantic memory stores of postmenopausal women. It was predicted that relationships between moderate drinking, ERT and cognition would be attenuated by demographic and health-related factors. Postmenopausal women (n = 298) completed a battery of cognitive tests designed to assess speed and accuracy of episodic and knowledge-based cognitive processing. Potentially confounding variables were categorized and tested as mediators in hierarchical regression analyses. Moderate drinking was a weak predictor of episodic availability prior to removal of potential mediators. ERT use was a significant predictor of episodic and knowledge-based availability; no mediators were identified. Alcohol moderated ERT, as a combined alcohol/ERT variable was shown to be related to cognition. Neither moderate drinking nor ERT use was associated with cognitive speed. These findings suggest that positive relationships between alcohol and cognition are likely mediated by other variables, and should not be regarded as a benefit of drinking. Further, results support ERT as a predictor of knowledge-based and episodic availability, independent of mood stabilization or socioeconomic influences. Finally, alcohol and ERT appear to interact to impact both episodic and knowledge-based performance.
Surgery and Risk of Sporadic Creutzfeldt-Jakob Disease in Denmark and Sweden: Registry-Based Case-Control Studies
Authors: Mahillo-Fernandez Ignacio , de Pedro-Cuesta Jesús , Bleda Maria José , Cruz Mabel , Mølbak Kåre , Laursen Henning , Falkenhorst Gerhard , Martínez-Martín Pablo , Siden Åke
Published: October 2008

Background: Epidemiologic evidence of surgical transmission of sporadic Creutzfeldt-Jakob disease (sCJD) remains controversial. Methods: From Danish and Swedish registries we selected 167 definite and probable sCJD cases (with onset between 1987 and 2003) and 3,059 controls (835 age-, sex-, and residence-matched, and 2,224 unmatched). Independent of case/control status, surgical histories were obtained from National Hospital Discharge Registries. Surgical procedures were categorized by body system group and lag time to onset of sCJD. Exposure frequencies were compared using logistic regression. Results: A history of any major surgery, conducted ≧20 years before sCJD onset, was more common in cases than both matched (OR = 2.44, 95% CI = 1.46–4.07) and unmatched controls (OR = 2.25, 95% CI = 1.48–3.44). This observation was corroborated by a linear increase in risk per surgical discharge (OR = 1.57, 95% CI = 1.13–2.18; OR = 1.50, 95% CI = 1.18–1.91). Surgery of various body systems, including peripheral vessels, digestive system and spleen, and female genital organs, was significantly associated with increased sCJD risk. Conclusions: A variety of major surgical procedures constitute a risk factor for sCJD following an incubation period of many years. A considerable number of sCJD cases may originate from health care-related accidental transmission.
Cellular Adhesion to Growth Surfaces: a Possible Role for Low Molecular Weight Surface Components
Authors: Wildridge M. , Sherbet G.V.
Published: October 2008

Cell lines initiated from a fibrocystic hyperplasia and a carcinoma of the breast and an established human fetal lung fibroblast line, MRC5, were grown in culture. The surface proteins of the cells were iodinated in cell monolayer, and in suspension following harvesting from culture flasks using EDTA. Data are presented which show that cells labelled in suspension show reduced incorporation of 125I into surface proteins of high molecular weight &(>100,000 daltons) and considerably increased incorporation into proteins with molecular weight& < 100,000 daltons. These changes are discussed in relation to the possible release of surface material by the action of EDTA. It is also suggested, on the basis of the current findings, that the detachment of cells may expose low molecular weight components possibly involved in the attachment of the cells to the substratum.
Systemic Anaphylaxis in Mast-Cell-Deficient Mice of W/Wv and Sl/Sld Genotypes
Authors: Ha Tai-You , Reed Norman D.
Published: October 2008

Active systemic anaphylaxis was induced in mast-cell-deficient mice of W/Wv and Sl/Sld genotypes. The mast-cell-deficient mice were successfully sensitized either by an intraperitoneal injection of chicken γ-globulin (CγG) mixed with adjuvant, alum and saline extract of Bordetella pertussis, or by an intravenous injection of CγG alone. Sensitized mice showed signs of systemic anaphylaxis and died after one or more intravenous challenge injections of CγG. These studies show that active systemic anaphylaxis can occur in mast-cell-deficient mice and suggest that cells other than mast cells may release adequate mediators to support systemic anaphylaxis.
Nicotine Augments Glomerular Injury in a Rat Model of Acute Nephritis
Authors: Jaimes Edgar A. , Tian Run-Xia , Joshi Mahesh S. , Raij Leopoldo
Published: October 2008

Background/Aims: Epidemiologic studies suggest that cigarette smoke worsens the progression of renal injury in patients with glomerular diseases. The mechanisms involved have not been elucidated. These studies were designed to determine whether nicotine worsens markers of inflammation including glomerular cell proliferation and fibronectin deposition in an in vivomodel of glomerular injury. Methods: Sprague-Dawley rats were injected with anti-Thy1 antibody and given either tap water or nicotine in the drinking water until sacrifice at day 14. Fibronectin expression was measured by Western blot and immunohistochemistry. COX-2 expression was also determined by Western blot in the kidney cortex of rats treated with nicotine and in cultured human mesangial cells treated with nicotine. Results: Anti-Thy1 antibody administration resulted in a significant increase in the number of cells per glomerulus that was further increased by the administration of nicotine. In nephritic rats, the administration of nicotine significantly increased fibronectin and COX-2 expression. In cultured human mesangial cells we also demonstrated that nicotine increases COX-2 expression and activity and that COX-2 mediates mesangial cell proliferation in response to nicotine. Conclusion: Either in vivo or in vitro treatment with nicotine leads to activation of inflammatory mediators and hallmarks of glomerular injury, which may explain the mechanisms involved in the deleterious effects of cigarette smoking on renal disease.
Experimental Study of Hormone Receptor Development in a Unicellular Model System
Authors: Csaba G. , Németh G. , Vargha P.
Published: October 2008

It was shown earlier that diiodotyrosine (T2) stimulates the growth of Tetrahymena. In the present study clonal populations of Tetrahymena, derived from subcultures propagated in the presence of T2, showed a highly significant increase of intra-clone variance over the control, while inter-clone variation was significant, but not decisive. This suggests that genetic factors play a smaller role in the development of the cell membrane receptor pattern than the genetic variability of the membrane itself, which seems to account for the stabilization of the adequate receptors on first exposure to a hormone.
Heme Oxygenase-1 Regulates Cardiac Mitochondrial Biogenesis via Nrf2-Mediated Transcriptional Control of Nuclear Respiratory Factor-1
Authors: Piantadosi Claude A. , Carraway Martha Sue , Babiker Abdelwahid , Suliman Hagir B.
Published: October 2008

Heme oxygenase (HO)-1 is a protective antioxidant enzyme that prevents cardiomyocyte apoptosis, for instance, during progressive cardiomyopathy. Here we identify a fundamental aspect of the HO-1 protection mechanism by demonstrating that HO-1 activity in mouse heart stimulates the bigenomic mitochondrial biogenesis program via induction of NF-E2–related factor (Nrf)2 gene expression and nuclear translocation. Nrf2 upregulates the mRNA, protein, and activity for HO-1 as well as mRNA and protein for nuclear respiratory factor (NRF)-1. Mechanistically, in cardiomyocytes, endogenous carbon monoxide (CO) generated by HO-1 overexpression stimulates superoxide dismutase-2 upregulation and mitochondrial H
2
O
2
production, which activates Akt/PKB. Akt deactivates glycogen synthase kinase-3β, which permits Nrf2 nuclear translocation and occupancy of 4 antioxidant response elements (AREs) in the
NRF-1
promoter. The ensuing accumulation of nuclear NRF-1 protein leads to gene activation for mitochondrial biogenesis, which opposes apoptosis and necrosis caused by the cardio-toxic anthracycline chemotherapeutic agent, doxorubicin. In cardiac cells, Akt silencing exacerbates doxorubicin-induced apoptosis, and in vivo CO rescues wild-type but not Akt1
−/−
mice from doxorubicin cardiomyopathy. These findings consign HO-1/CO signaling through Nrf2 and Akt to the myocardial transcriptional program for mitochondrial biogenesis, provide a rationale for targeted mitochondrial CO therapy, and connect cardiac mitochondrial volume expansion with the inducible network of xenobiotic and antioxidant cellular defenses.
Atorvastatin Reduces the Risk of Cardiovascular Events in Patients With Carotid Atherosclerosis
Authors: Sillesen Henrik , Amarenco Pierre , Hennerici Michael G. , Callahan Alfred , Goldstein Larry B. , Zivin Justin , Messig Michael , Welch K. Michael
Published: October 2008

Background and Purpose—

The Stroke Prevention by Aggressive Reduction in Cholesterol Levels (SPARCL) trial found that treatment with atorvastatin 80 mg per day reduced the risk of stroke and cardiovascular events in patients with a recent transient ischemic attack (TIA) or stroke. We hypothesized this benefit would be greatest in the subgroup of patients with carotid stenosis.

Methods—

The SPARCL trial randomized patients with TIA or stroke within 1 to 6 months without known coronary heart disease (CHD) and low-density lipoprotein cholesterol 100 to 190 mg/dL to treatment with atorvastatin 80 mg per day or placebo. Investigators identified subjects as having carotid stenosis not requiring revascularization at the time of randomization. Of the total SPARCL population, 1007 were documented as having carotid stenosis at baseline, 3271 did not, and the status of 453 was unknown.

Results—

We found no heterogeneity in the treatment effect for the SPARCL primary (fatal and nonfatal stroke) and secondary end points between the group with and without carotid stenosis. The group with carotid artery stenosis had greater benefit when all cerebro- and cardiovascular events were combined. In the group with carotid artery stenosis, treatment with atorvastatin was associated with a 33% reduction in the risk of any stroke (hazard ratio [HR] 0.67, 95% confidence interval [CI] 0.47, 0.94;
P
=0.02), and a 43% reduction in risk of major coronary events (HR 0.57, 95% CI 0.32, 1.00;
P
=0.05). Later carotid revascularization was reduced by 56% (HR 0.44, 95% CI 0.24, 0.79;
P
=0.006) in the group randomized to atorvastatin.

Conclusion—

Consistent with the overall results of the SPARCL intention to treat population, intense lipid lowering with atorvastatin reduced the risk of cerebro- and cardiovascular events in patients with and without carotid stenosis. The carotid stenosis group may have greater benefit.
Territorial Arterial Spin Labeling in the Assessment of Collateral Circulation
Authors: Chng Soke Miang , Petersen Esben Thade , Zimine Ivan , Sitoh Yih-Yian , Lim C.C. Tchoyoson , Golay Xavier
Published: October 2008

Background and Purpose—

Collateral circulation plays a vital role in patients with steno-occlusive disease, in particular for predicting stroke outcome. Digital subtraction angiography (DSA) is the gold standard for the assessment of collateral circulation, despite its invasive nature. Recently, the development of a new class of arterial spin labeling (ASL) methods allowed independent measurement of territorial flow information without the need for contrast media injection. Here, we compared combined territorial ASL (TASL) and MR angiography (MRA) against DSA in the assessment of collateral circulation.

Methods—

Eighteen patients presenting with extra- or intracranial arterial steno-occlusive disease were recruited. All DSA studies were performed using a biplane angiography unit. MR imaging consisted of time-of-flight MRA and TASL, performed at 3T. Collateral circulation on both modalities was evaluated in consensus in a double-blinded manner by 3 neuroradiologists.

Results—

Good agreement was found between DSA and TASL in the assessment of collateral flow: Cramer coefficient, V=0.53 (
P
<0.0001) and Contingency coefficient, C=0.67, with kappa=0.70 and kappa=0.72 in the assessment of flow and collaterals, respectively. TASL and DSA successfully evaluated 89% and 98% of the vessels, respectfully. Failure was linked to motion-related artifacts in TASL, and highly tortuous vessels in DSA. Generally, combined MRA-TASL was comparable to DSA in diagnostic quality.

Conclusions—

TASL provided radiological information comparable to DSA on collateral flow, with the advantage that it could be performed during routine MRI studies. TASL may provide insight on collateral perfusion in patients who may not otherwise be candidates for DSA, and may potentially replace it.
Impact of Fasting Glycemia and Regional Cerebral Perfusion in Diabetic Subjects
Authors: Cosentino Francesco , Battista Rodolfo , Scuteri Angelo , De Sensi Francesco , De Siati Luca , Di Russo Carmen , Camici Giovanni G. , Volpe Massimo
Published: October 2008

Background and Purpose—

Diabetes mellitus increases the risk of ischemic stroke. The aim of this study was to investigate the correlation between fasting plasma glucose (FPG) and changes in regional cerebral perfusion (CP) in subjects with DM.

Methods—

CP was assessed in 24 subjects (mean age 44±2.5 years) with type 1 diabetes mellitus by single photon emission computed tomography.

Results—

Analysis of CP during elevated FPG (224±24 mg/dL) showed 3 or more deficits in 42% of the subjects. A positive relationship between the number of CP deficits and FPG was observed (
P
<0.01), but not with age, sex, body mass index, or duration of diabetes mellitus. Regional deficits were reduced (
P
<0.001) with improvement in FPG (119±5 mg/dL). This reduction remained significant after adjustment for age, sex, and body mass index. Plasma levels of P-selectin, intercellular adhesion molecule-1, and vascular cell adhesion molecule-1, established markers of endothelial dysfunction, were significantly decreased with lower FPG. Furthermore, thiobarbituric acid reactive substance plasma levels, an index of oxidative stress, were also reduced (
P
<0.01).

Conclusions—

The present study demonstrates that changes in FPG are associated with functional changes in regional CP. Hyperglycemia-induced endothelial dysfunction may be implicated in the impaired regional CP of diabetic subjects.
Unruptured Intracranial Aneurysms
Authors: Ishibashi Toshihiro , Murayama Yuichi , Urashima Mitsuyoshi , Saguchi Takayuki , Ebara Masaki , Arakawa Hideki , Irie Koreaki , Takao Hiroyuki , Abe Toshiaki
Published: October 2008

Backgrounds and Purpose—

The authors evaluated the incidence of rupture of unruptured intracranial saccular aneurysm during observation.

Methods—

Between January 2003 and December 2006, a total of 419 patients with 529 unruptured intracranial saccular aneurysms were observed without treatment. The mean follow-up duration was 905.3 days. Aneurysm size was measured by 3-dimensional CT angiography. Clinical and 3-dimensional CT angiography follow-up were obtained every 6 months.

Results—

Nineteen aneurysms ruptured during observation resulting in a 1.4% rupture rate per year. A history of subarachnoid hemorrhage (hazard ratio, 7.3; 95% CI, 2.5 to 21.2), posterior circulation aneurysm (hazard ratio, 2.9; 95% CI, 1.1 to 8), and large size were significant independent predictors for aneurysm rupture.

Conclusions—

Size, history of subarachnoid hemorrhage, and posterior circulation aneurysms were significant risk factors for prediction of rupture of unruptured intracranial saccular aneurysms.
Abnormal Responses of the Human Cerebral Microcirculation to Papaverin During Aneurysm Surgery
Authors: Pennings Frederik A. , Albrecht Kees W. , Muizelaar J. Paul , Schuurman P. Richard , Bouma Gerrit J.
Published: October 2008

Background and Purpose—

The role of the cerebral microcirculation in delayed ischemia after subarachnoid hemorrhage remains obscure. To test the hypothesis that cerebral arterioles have a reduced capacity to dilate after subarachnoid hemorrhage, we studied the microvascular responses to papaverine (PPV) in patients undergoing aneurysm surgery.

Method—

In 14 patients undergoing aneurysm surgery, the diameter changes of cortical microvessels after topical application of PPV were observed using orthogonal polarizing spectral imaging.

Results—

In control subjects, neither arterioles nor venules showed diameter changes in response to topical PPV. In patients operated <48 hours after subarachnoid hemorrhage, PPV resulted in vasodilatation of arterioles with 45±41% increase in arteriolar diameter (
P
=0.012). In 2 of these patients, arteriolar diameter returned below baseline value. In patients undergoing late aneurysm clipping, the diameter increase of the arterioles after PPV was 25±24% (not significant). In 2 patients of this group, no vasodilatation but focal arteriolar narrowing occurred.

Conclusions—

In patients with subarachnoid hemorrhage, unpredictable response patterns to PPV were observed with “rebound” vasoconstriction suggesting increased contractility of the microcirculation. Yet, diminished vasodilatory capacity of the cerebral microcirculation after subarachnoid hemorrhage was not confirmed by this study.
Can Early Neurosonology Predict Outcome in Acute Stroke?
Authors: Stolz Erwin , Cioli Francesca , Allendoerfer Jens , Gerriets Tibo , Del Sette Massimo , Kaps Manfred
Published: October 2008

Background and Purpose—

Prediction of short- and long-term prognosis is an important issue in acute stroke care. This metaanalysis explores the prognostic value of initial bed-side transcranial ultrasound in acute stroke.

Methods—

All studies prospectively applying TCCS or TCD within 24 hours of symptom onset in acute stroke, with a minimal cohort size of 20 patients, and reporting clinical outcome variables in relation to the vascular findings were included into this metaanalysis. Study quality was assessed by 2 independent reviewers.

Results—

Twenty-five studies with 1813 included patients identified by electronic and manual search fulfilled the inclusion criteria. Middle cerebral artery (MCA) occlusion was associated with a significantly increased risk for a fatal course of stroke (OR 2.46, 95% CI 1.33 to 4.52). Patients with patent MCA were more likely to clinically improve within 4 days than patients with MCA occlusion (OR 11.11, 95% CI 5.44 to 22.69). Full recanalization within 6 hours after symptom onset was highly significantly associated with clinical improvement within 48 hours (OR 5.64, 95% CI 3.82 to 8.31) and functional independence after 3 months (OR 6.07, 95% CI 3.94 to 9.35).

Conclusions—

Transcranial ultrasound provides important information on prognosis in patients with acute stroke.
Patient-Specific Decision-Making for Warfarin Therapy in Nonvalvular Atrial Fibrillation
Authors: Eckman Mark H. , Wong Lawrence K.S. , Soo Yannie O.Y. , Lam Wynnie , Yang Song Ran , Greenberg Steven M. , Rosand Jonathan
Published: October 2008

Background and Purpose—

Intracerebral hemorrhage (ICH) accounts for a majority of long-term morbidity and mortality associated with bleeding while on warfarin. Both ICH and warfarin-related ICH appear to have a genetic component. Furthermore, advanced neuroimaging using MRI can now identify individuals at increased risk of ICH. We explore whether screening strategies that include genetic profiling and neuroimaging might improve the safety of chronic anticoagulation for atrial fibrillation by identifying individuals from whom warfarin should be withheld.

Methods—

We used a Markov state transition decision model. Effectiveness was measured in quality-adjusted life-years. Data sources included the English language literature using MEDLINE searches and bibliographies from selected articles along with empirical data from our institutions. The base case was a 69-year-old man with newly diagnosed nonvalvular atrial fibrillation.

Results—

For patients at average risk for thromboembolic events and known to possess a hypothetical genetic profile increasing risk for warfarin ICH, anticoagulation remains the preferred strategy until the relative hazard of ICH exceeds 23.8. Genetic profiling would be favored for patients at low risk of thromboembolism (1.5% per year) if the hypothetical gene variant(s) conferred a relative risk of ICH >4.1. Screening strategies in which patients underwent genotyping and MRI before anticoagulation did not improve aggregate patient outcomes unless the predictive power of MRI exceeded current best guess estimates and patients were at low to moderate risk of thromboembolism.

Conclusion—

Currently identified genetic markers of bleeding risk do not confer a risk of ICH sufficiently high to warrant routine genetic testing for patients at average risk of thromboembolism. Even if patients undergo screening with MRI as well as genotyping, currently available data on the role of MRI on risk of ICH and warfarin ICH do not support use of these tests for withholding anticoagulation in patients with atrial fibrillation.
Soviet Support for Egypt's Intervention in Yemen, 1962–1963
Authors: Ferris Jesse
Published: October 2008

Drawing on documents and memoirs in Russian and Arabic, this article tells the unknown story of Soviet-Egyptian cooperation in the early phases of the Yemeni Civil War, a war that broke out while much of the world's attention was focused on the Cuban missile crisis and the war between India and Pakistan. Egypt's fateful decision to intervene in the conflict was dependent on substantial Soviet backing, which strengthened the relationship between the USSR and Gamal Abdel Nasser's government in Egypt. In response to a plea from Nasser, Nikita Khrushchev authorized the military transport branch of the Soviet Air Force to embark on a clandestine airlift operation ferrying Egyptian troops into Yemen to shore up the new government there.
From the Open Skies Proposal of 1955 to the Norstad Plan of 1960: A Plan Too Far
Authors: Tal David
Published: October 2008

A proposal drafted by General Lauris Norstad for the creation of a limited inspection zone in Central Europe and in the Arctic Circle—a proposal that came to be known as the Norstad Plan—evolved out of President Dwight D. Eisenhower's Open Skies proposal. The proposal, based on ideas promoted by Eisenhower's disarmament adviser, Harold Stassen, departed from traditional U.S. disarmament policy. The plan was eventually aborted by West Germany and France, but the document heralded a shift in Eisenhower's disarmament policy. The president was ready to give up the all-or-nothing approach and adopt an incremental approach. To this end, the United States would make concessions that would render U.S. proposals more acceptable to the Soviet Union. The plan adumbrated the conceptual change that paved the way for the Limited Nuclear Test Ban Treaty and the Non-Proliferation Treaty.
Spirit and Spirituality: Philosophical Trends in Late Modern Pneumatology
Authors: Shults F. LeRon
Published: October 2008

This dialogue piece reviews some of the key developments in the doctrine of the Holy Spirit in late modern theology that have contributed to the scholarly and practical integration of pneumatology and Christian spirituality. Shifts in the meaning and use of three concepts — matter, person, and force — have played a particularly influential role in these developments. These trends are illustrated in several recent pneumatological proposals. The final section outlines some new directions for the ongoing task of reforming pneumatology.
Filtering Diversity
Authors: Poster Winifred R.
Published: October 2008

The spread of corporate diversity programs in the past decade has meant renewed attention to the rhetoric of fairness in employment relations. A number of organizational dynamics can derail this project, however, especially at the transnational level. In the author's case studies of a U.S. high-tech firm (AmCo) and its subsidiary in India (TransCo), this happens through a filtering process, in which managers disassemble broad themes of diversity and repackage them in more narrow and exclusive terms. In the United States, the discourse of gender is more legitimate, whereas in India, it is ethnicity/race. These discourses of diversity have both positive and negative implications. They are used by managers to divert attention from overt forms of stratification and avoid disruptions in employee relations, yet they also generate a mutual critique between the two firms that can help to overcome the filtering process and achieve a more integrated understanding of discrimination.
The Racialization of Global Labor
Authors: Bonacich Edna , Alimahomed Sabrina , Wilson Jake B.
Published: October 2008

Drawing on both historical and contemporary examples, the authors argue that today's global capitalist system is maintained and structured within a global system of White supremacy. Groups of workers are located within a hierarchically organized, racialized labor system that differentially exploits workers based upon their racialized and gendered location. Dominant racialized labor groups (mainly White/European workers) are in general afforded more privileges than subordinate racialized labor groups (workers of color), who face the denial of basic citizenship rights and higher degrees of exploitation and inferior working conditions.
Gender and Economic Change in the United States and Mexico, 1900-2000
Authors: Fernández-Kelly Patricia
Published: October 2008

This article investigates the relationship between changing gender definitions and economic development in the United States and Mexico over the course of a century. On the basis of historical research and fieldwork, the author highlights the role played by the national state in both countries in defining the proper ambit and behavior of men and women. She maintains that gender is a central vector in the organization of class hierarchies. Then, the author discusses the effects of global economic integration on gender definitions, arguing that the present era is characterized by the virtual disappearance of the family wage and growing atomization of the labor force in terms of gender. Finally, she provides an analysis of strategic sectors differentiated in terms of gender, race, and national background. Included are women working in export-processing zones, a new technocratic class residing in global cities, displaced White workers, and radicalized urban populations.
Global Care Crisis
Authors: Isaksen Lise Widding , Devi Sambasivan Uma , Hochschild Arlie Russell
Published: October 2008

More and more of the world's migrants are mothers who leave their families in the villages of the South to take up jobs caring for families in the North. Most current research on this trend focuses on the conditions of work that such migrant mothers face in the North or on the children she leaves in the South, understood as a rearrangement of roles in the family. Here, the authors call for a macro-analytic theory of the effect of such migration and consider two alternate views. According to one, the care of children in the South involves a transfer of “social capital” from South to North. According to the other, it involves a more fundamental erosion of the “commons” of the South by the markets of the North. The latter, the authors propose, best captures the full nature of this important hidden injury of global capitalism.
Class Backgrounds, Modes of Incorporation, and Puerto Ricans' Pathways Into the Transnational Professional Workforce
Authors: Aranda Elizabeth M.
Published: October 2008

Patterns of labor market incorporation of two samples of middle-class Puerto Ricans (U.S. migrants and return migrants to the Island) are examined in this article. Particular attention is paid to the diverse class backgrounds of Puerto Rican professionals and how these backgrounds (and how they structure migration options) impact educational attainment. The author also examines the resources and opportunities garnered through U.S. citizenship, specifically among those from working-class/poor backgrounds who are more likely to be structurally constrained in their efforts to achieve social mobility. The author further analyzes the direct and indirect impact of these factors on Puerto Ricans' incorporation into mainland and Island labor markets and their entry into the transnational professional workforce.
Two Stops in Today's New Global Geographies
Authors: Sassen Saskia
Published: October 2008

The key variable is the incipient formation of global labor markets at the top and bottom of the economic system. At the top there is the transnational market for high-level managerial and professional talent across economic sectors, from finance to engineering; this market is increasingly shaped by public and private regulations. At the bottom one finds an amalgamation of mostly informal flows, with the “global care chains” among the most visible ones. There are sites of complex intersection between these two markets. The two sites singled out for examining the formation of these labor circuits are the global city and a set of Global South countries subject to the international debt-financing regime that puts governments, firms, and households under enormous constraints to survive. Emigration and people trafficking now generate money flows that help governments, firms, and households survive. The focus is especially on lower labor circuits and their feminizing.
Gangkill: An Exploratory Empirical Assessment of Gang Membership, Homicide Offending, and Prison Misconduct
Authors: Drury Alan J. , DeLisi Matt
Published: October 2008

Extant research indicates that inmates with street gang history are prone for prison misconduct but that inmates convicted of homicide offenses are less likely to be noncompliant. No research has explored the interaction between street gang history and homicide offending. Based on official infraction data from 1,005 inmates selected from the Southwestern United States, the current study found that inmates with street gang history and convictions for homicide offenses were significantly involved in six types of institutional misconduct, net the effects of homicide offending, offense severity, street and prison gang risk, violence history, and demographics. Implications for theory and research are explored.