bluuebunny/crossref_metadata_2025 huggingface dataset:
Prevalence of headache in Australian footballers: Table 1
Authors: McCrory P , Heywood J , Coffey C
Published: January 2005

Objective:To survey the prevalence and risk factors for headache in a population of elite professional Australian footballers.

Methods:A prospective questionnaire based survey was performed on elite Australian footballers participating in a national competition. The survey was designed to assess the prevalence and risk factors for headache using standardised International Headache Society (HIS) criteria. Headache prevalence was compared with that of an age and sex matched community control population.

Results:A total of 160 questionnaires were analysed. Headaches were reported by 80% of subjects, with 49% of respondents reporting headaches during competitive match play and 60% during training. There was no significant difference between the footballers and the community sample in the number of headaches ever; however, they did report more headaches in the three months before the survey —that is, during the competitive playing season. In the footballers, 22% of headaches conformed to the strict IHS definition of migraine headaches. When the relaxed definition of “footballer’s migraine” was used, 34% of headaches met these criteria. Footballers were at significantly increased risk of footballer’s migraine than community controls.

Conclusions:Headaches are common in Australian footballers, and the prevalence of migraine is increased in relation to community prevalence studies. Furthermore, the strict IHS criteria may not adequately identify the specific subtype of football related headache. This finding has important implications in the management of headache in this setting.
Paediatric sport related concussion pilot study
Authors: McCrory P , Davis G
Published: January 2005

This article has been retracted. See the retraction notice for details. The PDF is retained for transparency.
Ischemia of rat stomach mobilizes ECL cell histamine
Authors: Kitano Masayuki , Bernsand Maria , Kishimoto Yosuke , Norlén Per , Håkanson Rolf , Haenuki Yoko , Kudo Masatoshi , Hasegawa Junichi
Published: January 2005

Microdialysis was used to study how ischemia-evoked gastric mucosal injury affects rat stomach histamine, which resides in enterochromaffin-like (ECL) cells and mast cells. A microdialysis probe was inserted into the gastric submucosa, and the celiac artery was clamped (30 min), followed by removal of the clamp. Microdialysate histamine was determined by enzyme-linked immunosorbent assay. In addition, we studied the long-term effects of ischemia on the oxyntic mucosal histidine decarboxylase activity in omeprazole-treated rats. Gastric mucosal lesions induced by the ischemia were enlarged on removal of the clamp. The microdialysate histamine concentration increased immediately on clamping (50-fold rise within 30 min) and declined promptly after the clamp was removed. In contrast, histidine decarboxylase activity of the ECL cells was lowered by the ischemia and returned to preischemic values 9 days later. Mast cell-deficient rats responded to ischemia-reperfusion much like wild-type rats with respect to histamine mobilization. Pretreatment with the irreversible inhibitor of histidine decarboxylase, α-fluoromethylhistidine, which is known to eliminate histamine from ECL cells, prevented the rise in microdialysate histamine. Pharmacological blockade of acid secretion (cimetidine or omeprazole) prevented the lesions induced by ischemia-reperfusion insult but not the mobilization of histamine. In conclusion, ischemia of the celiac artery mobilizes large amounts of histamine from ECL cells, which occurs independently of the gross mucosal lesions. The prompt reduction of the mucosal histidine decarboxylase activity in response to ischemia probably reflects ECL cell damage. The lesions develop not because of mobilization of histamine per se but because of ischemia plus reperfusion plus gastric acid.
P2X and P2Y purinergic receptors on human intestinal epithelial carcinoma cells: effects of extracellular nucleotides on apoptosis and cell proliferation
Authors: Coutinho-Silva Robson , Stahl Lynn , Cheung Kwok-Kuen , de Campos Nathalia Enes , de Oliveira Souza Carolina , Ojcius David M. , Burnstock Geoffrey
Published: January 2005

Extracellular nucleotides interact with purinergic receptors, which regulate ion transport in a variety of epithelia. With the use of two different human epithelial carcinoma cell lines (HCT8 and Caco-2), we have shown by RT-PCR that the cells express mRNA for P2X1, P2X3, P2X4, P2X5, P2X6, P2X7, P2Y1, P2Y2, P2Y4, P2Y6, P2Y11, and P2Y12receptors. Protein expression for P2Y1and P2Y2receptors was also demonstrated immunohistochemically, and P2X receptor subtype protein was present in the following decreasing order: P2X4> P2X7> P2X1> P2X3> P2X6> P2X5>> P2X2. The functional presence of P2X7, P2Y1, P2Y2, and P2Y4receptors was shown based on the effect of extracellular nucleotides on apoptosis or cell proliferation, and measurement of nucleotide-dependent calcium fluxes using a fluorometric imaging plate reader in the presence of different selective agonists and antagonists. ATP, at high concentrations, induced apoptosis through ligation of P2X7and P2Y1receptors; conversely, ATP, at lower concentrations, and UTP stimulated proliferation, probably acting via P2Y2receptors. We therefore propose that stimulation or dysfunction of purinergic receptors may contribute at least partially to modulation of epithelial carcinoma cell proliferation and apoptosis.
Essential fatty acid deficiency in mice is associated with hepatic steatosis and secretion of large VLDL particles
Authors: Werner Anniek , Havinga Rick , Bos Trijnie , Bloks Vincent W. , Kuipers Folkert , Verkade Henkjan J.
Published: January 2005

Essential fatty acid (EFA) deficiency in mice decreases plasma triglyceride (TG) concentrations and increases hepatic TG content. We evaluated in vivo and in vitro whether decreased hepatic secretion of TG-rich very low-density lipoprotein (VLDL) contributes to this consequence of EFA deficiency. EFA deficiency was induced in mice by feeding an EFA-deficient (EFAD) diet for 8 wk. Hepatic VLDL secretion was quantified in fasted EFAD and EFA-sufficient (EFAS) mice using the Triton WR-1339 method. In cultured hepatocytes from EFAD and EFAS mice, VLDL secretion into medium was measured by quantifying [3H]-labeled glycerol incorporation into TG and phospholipids. Hepatic expression of genes involved in VLDL synthesis and clearance was measured, as were plasma activities of lipolytic enzymes. TG secretion rates were quantitatively similar in EFAD and EFAS mice in vivo and in primary hepatocytes from EFAD and EFAS mice in vitro. However, EFA deficiency increased the size of secreted VLDL particles, as determined by calculation of particle diameter, particle sizing by light scattering, and evaluation of the TG-to-apoB ratio. EFA deficiency did not inhibit hepatic lipase and lipoprotein lipase activities in plasma, but increased hepatic mRNA levels of apoAV and apoCII, both involved in control of lipolytic degradation of TG-rich lipoproteins. EFA deficiency does not affect hepatic TG secretion rate in mice, but increases the size of secreted VLDL particles. Present data suggest that hypotriglyceridemia during EFA deficiency is related to enhanced clearance of altered VLDL particles.
Regression of pressure overload-induced left ventricular hypertrophy in mice
Authors: Gao Xiao-Ming , Kiriazis Helen , Moore Xiao-Lei , Feng Xin-Heng , Sheppard Karen , Dart Anthony , Du Xiao-Jun
Published: January 2005

As a prelude to investigating the mechanism of regression of pressure overload-induced left ventricular (LV) hypertrophy (LVH), we studied the time course for the development and subsequent regression of LVH as well as accompanying alterations in cardiac function, histology, and gene expression. Mice were subjected to aortic banding for 4 or 8 wk to establish LVH, and regression was initiated by release of aortic banding for 6 wk. Progressive increase in LV mass and gradual chamber dilatation and dysfunction occurred after aortic banding. LVH was also associated with myocyte enlargement, interstitial fibrosis, and enhanced expression of atrial natriuretic peptide, collagen I, collagen III, and matrix metalloproteinase-2 but suppressed expression of α-myosin heavy chain and sarcoplasmic reticulum Ca2+-ATPase. Aortic debanding completely or partially reversed LVH, chamber dilatation and dysfunction, myocyte size, interstitial fibrosis, and gene expression pattern, each with a distinct time course. The extent of LVH regression was dependent on the duration of pressure overload, evidenced by the fact that restoration of LV structure and function was complete in animals subjected to 4 wk of aortic banding but incomplete in animals subjected to 8 wk of aortic banding. In conclusion, LVH regression comprises a variety of morphological, functional, and genetic components that show distinct time courses. A longer period of pressure overload is associated with a slower rate of LVH regression.
Magnetic resonance stress tagging in ischemic heart disease
Authors: Paetsch Ingo , Föll Daniela , Kaluza Adam , Luechinger Roger , Stuber Matthias , Bornstedt Axel , Wahl Andreas , Fleck Eckart , Nagel Eike
Published: January 2005

High-dose dobutamine magnetic resonance stress testing has been shown to be superior to dobutamine stress echocardiography for diagnosis of coronary artery disease (CAD). We determined the feasibility of quantitative myocardial tagging during low- and high-dose dobutamine stress and tested the ability of global systolic and diastolic quantitative parameters to identify patients with significant CAD. Twenty-five patients suspected of having significant CAD were examined with a standard high-dose dobutamine/atropine stress magnetic resonance protocol (1.5-T scanner, Philips). All patients underwent invasive coronary angiography as the standard of reference for the presence ( n = 13) or absence ( n = 12) of significant CAD. During low-dose dobutamine stress, systolic (circumferential shortening, systolic rotation, and systolic rotation velocity) and diastolic (velocity of circumferential lengthening and diastolic rotation velocity) parameters changed significantly in patients without CAD (all P < 0.05 vs. rest) but not in patients with CAD. Identification of patients without and with CAD during low-dose stress was possible using the diastolic parameter of “time to peak untwist.” At high-dose stress, none of the global systolic or diastolic parameters showed the potential to identify the presence of significant CAD. With myocardial tagging, a quantitative analysis of systolic and diastolic function was feasible during low- and high-dose dobutamine stress. In our study, the diastolic parameter of time to peak untwist as assessed during low-dose dobutamine stress was the most promising global parameter for identification of patients with significant CAD. Thus quantitative myocardial tagging may become a tool that reduces the need for high-dose dobutamine stress.
Cytosolic NADH redox and thiol oxidation regulate pulmonary arterial force through ERK MAP kinase
Authors: Oeckler Richard A. , Arcuino Elizabeth , Ahmad Mansoor , Olson Susan C. , Wolin Michael S.
Published: January 2005

An ERK MAP kinase-mediated contractile mechanism previously reported to be activated by peroxide and stretch in bovine coronary arteries is shown in this study to be present in endothelium-denuded bovine pulmonary arteries and subject to regulation by modulation of cytosolic NAD(H) redox through the lactate dehydrogenase reaction. Although our previous work identified an acute Po2-dependent peroxide-mediated relaxation of bovine pulmonary arteries on exposure to lactate, a 30-min treatment with 10 mM lactate enhanced ERK phosphorylation and increased force generation to 30 mM KCl. Hypoxia inhibited these responses to lactate. Increases in ERK phosphorylation and the enhancement of force generation by lactate and stretch are attenuated in the presence of inhibitors of Nox oxidase (0.1 mM apocynin) or ERK activation (10 μM PD-98059) and by 0.1 mM ebselen. Additionally, incubation of pulmonary arteries with 10 mM pyruvate lowered basal levels of ERK phosphorylation, and it inhibited both the ERK phosphorylation and the enhancement in force generation to 30 mM KCl caused by stretch. Treatment of pulmonary arteries with the thiol oxidant diamide (1 μM) elicited what appears to be a peroxide-independent increase in force and ERK phosphorylation that were both attenuated by PD-98059. Thus pulmonary arteries possess a peroxide-elicited contractile mechanism involving ERK MAP kinase, which is stimulated by stretch and regulated through the control of Nox oxidase activity by the availability of cytosolic NADH.
Trimethylthiazoline supports conditioned flavor avoidance and activates viscerosensory, hypothalamic, and limbic circuits in rats
Authors: Myers Elizabeth A. , Rinaman Linda
Published: January 2005

Interoceptive stimuli modulate stress responses and emotional state, in part, via ascending viscerosensory inputs to the hypothalamus and limbic forebrain. It is unclear whether similar viscerosensory pathways are recruited by emotionally salient exteroceptive stimuli, such as odors. To address this question, we investigated conditioned avoidance and central c-Fos activation patterns in rats exposed to synthetic trimethylthiazoline (TMT), an odiferous natural component of fox feces. Experiment 1 demonstrated that rats avoid consuming novel flavors that previously were paired with TMT exposure, evidence that TMT supports conditioned flavor avoidance. Experiment 2 examined central neural systems activated by TMT. Odor-naive rats were acutely exposed to low or high levels of TMT or a novel nonaversive control odor and were perfused with fixative 60–90 min later. A subset of rats received retrograde neural tracer injections into the central nucleus of the amygdala (CeA) 7–10 days before odor exposure and perfusion. Brain sections were processed for dual-immunocytochemical detection of c-Fos and other markers to identify noradrenergic (NA) neurons, corticotropin-releasing hormone (CRH) neurons, and retrogradely labeled neurons projecting to the CeA. Significantly greater proportions of medullary and pontine NA neurons, hypothalamic CRH neurons, and CeA-projecting neurons were activated in rats exposed to TMT compared with activation in rats exposed to the nonaversive control odor. Thus the ability of TMT to support conditioned avoidance behavior is correlated with significant odor-induced recruitment of hypothalamic CRH neurons and brain stem viscerosensory inputs to the CeA.
Cytokine profiles in the testes of rats treated with lipopolysaccharide reveal localized suppression of inflammatory responses
Authors: O'Bryan Moira K. , Gerdprasert Orapin , Nikolic-Paterson David J. , Meinhardt Andreas , Muir Julie A. , Foulds Lynda M. , Phillips David J. , de Kretser David M. , Hedger Mark P.
Published: January 2005

Evidence indicates that the testis possesses a reduced capacity to mount inflammatory and rejection responses, which undoubtedly contributes to the ongoing survival of the highly immunogenic germ cells. The contribution of local cytokine expression to this condition was investigated in adult male rats treated with lipopolysaccharide to induce inflammation. Cytokine mRNA and protein expression were determined in tissue extracts and fluids by Northern blot analysis, quantitative PCR, or RNAse protection assay and specific ELISAs. Testicular expression of the proinflammatory cytokines, interleukin (IL)-1β and tumor necrosis factor-α was considerably attenuated compared with the liver (control tissue); in contrast, the testicular IL-6 response was enhanced. Expression of IL-10, a type 2 immunoregulatory cytokine, was similar in both testis and liver, whereas the immunoregulatory/anti-inflammatory cytokines transforming growth factor-β1and activin A were constitutively elevated in both normal and inflamed testes. The IL-1β and transforming growth factor-β1proteins were present principally in their latent (inactive) forms, indicating that enzymic processing is an important control mechanism for these two cytokines within the testis. These data indicate that inflammatory and regulatory cytokine activity is regulated at both transcriptional and posttranslational levels in a testis-specific manner. It is concluded that a novel pattern of suppression of proinflammatory cytokine responses and normal or elevated expression of immunoregulatory cytokines may be responsible for reduced inflammatory responses and enhanced graft survival in the testis. These data have important implications for the understanding and treatment of male autoimmune infertility, testicular inflammation. and carcinogenesis.
Effect of glutamine on water and sodium absorption in human jejunum at baseline and during PGE1-induced secretion
Authors: Coëffier Moïse , Hecketsweiler Bernadette , Hecketsweiler Philippe , Déchelotte Pierre
Published: January 2005

Glutamine, a major fuel for enterocytes, stimulates water and sodium absorption in animal models of secretory diarrhea, but data in humans are still limited. The aim of this study was to investigate the effect of glutamine on jejunal absorption during hypersecretion in humans. In six healthy adults, the effects of glutamine on jejunal absorption were assessed with a triple-lumen tube on two occasions, at baseline and during PGE1-induced hypersecretion (0.1 μg·kg−1·min−1) in a random order. Isoosmolar solutions containing polyethylene glycol 4000 as nonabsorbable marker were infused in the jejunum at 10 ml/min over 1-h periods: saline (sodium chloride 308 mmol/l), glucose-mannitol 45:45 mM, glucose 90 mM, alanine-glucose 45:45 mM, glutamine-glucose 45:45 mM, and glutamine 90 mM. Net absorptive and secretory fluxes were measured at steady state. At baseline, glutamine- and alanine-containing solutions induced a threefold increase of water and sodium absorption ( P < 0.05); 90 mM glutamine stimulated water absorption more than 90 mM glucose (3.6 ± 0.6 vs. 1.9 ± 0.3 ml·min−1·30 cm−1, P < 0.05). PGE1-induced hypersecretion was reduced ( P < 0.05) by solutions of alanine-glucose, glutamine-glucose, and glutamine 90 mM ( P < 0.05) and reversed to absorption by alanine-glucose and glutamine-glucose. Glutamine and alanine absorption was nearly complete and was not influenced by PGE1. In conclusion, glutamine stimulates water and electrolyte absorption in human jejunum, even during experimental hypersecretion. In addition to the metabolic effects of glutamine, these results support the evaluation of glutamine-containing solutions for the rehydration and the nutritional support of patients with secretory diarrhea.
Genetic determinants on rat chromosome 6 modulate variation in the hypercapnic ventilatory response using consomic strains
Authors: Dwinell M. R. , Forster H. V. , Petersen J. , Rider A. , Kunert M. P. , Cowley A. W. , Jacob H. J.
Published: January 2005

To understand the genetic basis of pathways involved in the control of breathing, a large scale, high-throughput study using chromosomal substitution strains of rats is underway. Eight new consomic rat stains (SS-2BN, SS-4BN, SS-6BN, SS-7BN, SS-8BN, SS-11BN, SS-12BN, SS-14BN, SS-YBN), containing one homozygous BN/NHsdMcwi (BN) chromosome on a background of SS/JrHsdMcwi (SS), were created by PhysGen ( http://pga.mcw.edu ) Program for Genomic Applications. Male and female rats were studied using standard plethysmography under control conditions and during acute hypoxia (inspired oxygen fraction = 0.12) and hypercapnia (inspired CO2fraction = 0.07). The rats were also studied during treadmill exercise. Both male and female BN rats had a significantly lower ventilatory response during 7% CO2compared with SS rats of the same gender. SS-6BNfemale rats had a significantly reduced ventilatory response, similar to BN rats due primarily to a reduced tidal volume. Male SS-6BNrats had a significantly reduced tidal volume response to hypercapnia but a slightly increased frequency response during hypercapnia. Gene(s) on the Y chromosome may play a role in this increased frequency response in the male rats because the SS-YBNhypercapnic ventilatory response involves a significantly increased frequency response. Several chromosomal substitutions slightly altered the ventilatory responses to hypoxia and exercise. However, genes on chromosomes 6 and Y of those studied are of primary importance in aspects of ventilatory control currently studied.
Effect of body tilt on calf muscle performance and blood flow in humans
Authors: Egaña Mikel , Green Simon
Published: January 2005

To explore the effect of posture on muscle performance, we tested the effects of body tilt angle on the strength, endurance, and fatigue of, and blood flow into, the plantar flexors. Human subjects were fixed to a tilt table that could tilt them from the horizontal (0°) to upright (90°) position and enabled force to be applied to a footplate through isometric action of the right calf muscle. In experiment 1, six subjects performed a strength test and graded test (intermittent contractions) to the point of failure at three tilt angles (0, 47, and 90°). In Experiment 2, seven subjects performed a strength test and constant-force test [70% maximum force (Fmax); intermittent contractions] to the point of failure in the horizontal and three inclined positions (32, 47, and 67°). In experiment 3, leg blood flow was assessed during constant-force exercise at two intensities (30 and 70% Fmax) and two tilt angles (0 and 67°) in six subjects. Strength was not affected ( P > 0.05) by tilt angle. Time to failure during the graded test was significantly higher at 47° (25.9 ± 2.0 min) and 90° (25.1 ± 3.0 min) than 0° (22.2 ± 2.6 min). Time to failure during the constant-force test was also significantly higher at 32° (7.1 ± 3.6 min), 47° (8.0 ± 5.2 min), and 67° (8.6 ± 5.6 min) compared with 0° (4.0 ± 2.6 min). When graded or constant-force exercise was performed with arterial flow to the leg eliminated, there were no differences in exercise time between the horizontal and an inclined position. During nonischemic exercise, leg blood flow was significantly higher during exercise in the inclined position. These results demonstrate that head-up tilt improves endurance of the plantar flexors, that this effect occurs in the absence of an effect on strength, and that it depends on an intact peripheral circulation. Moreover, the postural effect on muscle endurance appears to be due to a greater blood flow into the leg, an effect that is established during the initial contractions.
Activated Forkhead Transcription Factor Inhibits Neointimal Hyperplasia After Angioplasty Through Induction of p27
Authors: Park Kyung-Woo , Kim Dae-Hee , You Hyun-Jung , Sir Jung-Ju , Jeon Soo-In , Youn Seock-Won , Yang Han-Mo , Skurk Carsten , Park Young-Bae , Walsh Kenneth , Kim Hyo-Soo
Published: January 2005

Objective—

We examined the effects of FKHRL1 (forkhead transcription factor in rhabdomyosarcoma like-1) overexpression on vascular smooth muscle cell (VSMC) proliferation, apoptosis, and cell cycle, in vitro, and the role of FKHRL1 and p27 in the pathophysiology of neointimal growth after balloon angioplasty, in vivo. Furthermore, we tested whether FKHRL1 overexpression can inhibit neointimal hyperplasia in a rat carotid artery model.

Methods and Results—

Adenovirus expressing the constitutively active FKHRL1 (FKHRL1-TM; triple mutant) with 3 Akt phosphorylation sites mutated was transfected to subconfluent VSMCs. FKHRL1 overexpression in cultured VSMCs increased p27 expression, leading to G1 phase cell-cycle arrest and increased apoptosis. In vivo, the phosphorylation of FKHRL1 increased significantly 3 hours after balloon injury and decreased thereafter, with the subsequent downregulation of p27. Although the phosphorylation of FKHRL1 was greatest at 3 hours, the downregulation of p27 showed a temporal delay, only slightly starting to decrease after 3 hours and reaching a nadir at 72 hours after balloon injury. Gene transfer of FKHRL1-TM increased p27, decreased proliferation, and increased apoptosis of VSMCs, which resulted in a marked reduction in neointima formation (intima-to-media ratio: 0.31±0.13 versus 1.17±0.28, for FKHRL1-TM versus Adv-GFP;
P
<0.001).

Conclusion—

Balloon angioplasty leads to the phosphorylation of FKHRL1 and decreased expression of p27, thereby promoting a proliferative phenotype in VSMCs in vitro and in vivo. This study reveals the importance of FKHRL1 in proliferation and viability of VSMCs and suggests that it may serve as a molecular target for interventions to reduce neointima formation after angioplasty.
Hyperglycemia Reduces Survival and Impairs Function of Circulating Blood-Derived Progenitor Cells
Authors: Kränkel Nicolle , Adams Volker , Linke Axel , Gielen Stephan , Erbs Sandra , Lenk Karsten , Schuler Gerhard , Hambrecht Rainer
Published: January 2005

Objective—

Function and availability of circulating progenitor cells (CPC) have been shown to be impaired in patients with diabetes mellitus (DM). Therefore, the aim of the present study was to analyze possible mechanisms leading to the reduction of CPC amount and function.

Methods and Results—

Peripheral blood mononuclear cells (MNCs) of healthy donors (n=15) were cultivated under hyperglycemia (HG) conditions (12 mmol/L D-Glucose) or in osmotic control medium (Con) (5 mmol/L D-Glucose plus 7 mmol/L L-Glucose) for 7 days. CPC amount was determined by uptake of acetylated low-density lipoprotein and lectin binding. On the functional level, cell cycle status, nitric oxide (NO) production, and migrational and integrative capacity of CPCs were assessed. HG conditions caused a significant decrease in CPC amount derived from healthy MNCs. Furthermore, HG conditions led to a functional impairment, reflected in a decreased NO production and matrix metalloproteinase (MMP)-9 activity, as well as an impairment of the migrational and integrative capacities.

Conclusion—

HG, a main feature of DM, affects important functional characteristics of CPCs. These results may provide further insight into the pathomechanism of endothelial dysfunction in HG.
Mesoangioblasts, Vessel-Associated Multipotent Stem Cells, Repair the Infarcted Heart by Multiple Cellular Mechanisms
Authors: Galli Daniela , Innocenzi Anna , Staszewsky Lidia , Zanetta Lucia , Sampaolesi Maurilio , Bai Antonio , Martinoli Elena , Carlo Eleonora , Balconi Giovanna , Fiordaliso Fabio , Chimenti Stefano , Cusella Gabriella , Dejana Elisabetta , Cossu Giulio , Latini Roberto
Published: January 2005

Objective—

To test the potential of mesoangioblasts (Mabs) in reducing postischemic injury in comparison with bone marrow progenitor cells (BMPCs), fibroblasts (Fbs), and embryonic stem cell–derived endothelial cells (ECs), and to identify putative cellular protective mechanisms.

Methods and Results—

Cells were injected percutaneously in the left ventricular (LV) chamber of C57BL/6 mice, 3 to 6 hours after coronary ligation, and detected in the hearts 2 days and 6 weeks later. Echocardiographic examinations were performed at 6 weeks. LV dilation was reduced and LV shortening fraction was improved with Mabs and BMPCs but not with ECs and Fbs. Donor cell colonization of the host myocardium was modest and predominantly in the smooth muscle layer of vessels. Capillary density was higher in the peripheral infarct area and apoptotic cardiomyocytes were fewer with Mabs and BMPCs. Mabs and BMPCs, but not Fbs or ECs, promoted survival of cultured cardiocytes under low-oxygen in culture. This activity was present in Mab-conditioned medium and could be replaced by a combination of basic fibroblast growth factor (bFGF), insulin-like growth factor (IGF)-1, and hepatocyte growth factor (HGF), all of which are produced by these cells. Conditioned medium from Mabs, but not from Fbs, stimulated proliferation of smooth muscle cells in vitro.

Conclusions—

Mabs appear as effective as BMPCs in reducing postinfarction LV dysfunction, likely through production of antiapoptotic and angiogenic factors.
15-Deoxy-Δ12,14-Prostaglandin J2(15d-PGJ2) Signals Through Retinoic Acid Receptor–Related Orphan Receptor-α but Not Peroxisome Proliferator–Activated Receptor-γ in Human Vascular Endothelial Cells
Authors: Migita Hideyuki , Morser John
Published: January 2005

Objective—15-Deoxy-Δ12,14-prostaglandin J2(15d-PGJ2), a natural ligand of the peroxisome proliferator–activated receptor-γ (PPARγ), has been shown to inhibit proinflammatory gene expression, but the signaling mechanisms involved remain unclear. Because retinoic acid receptor–related orphan receptor-α (RORα) has been reported to suppress tumor necrosis factor-α (TNF-α)–induced expression of proinflammatory genes, we hypothesized that 15d-PGJ2 may induce RORα expression resulting in inhibition of proinflammatory gene expression.

Methods and Results—We demonstrate that 15d-PGJ2 induced RORα1 and RORα4 expression and inhibited TNF-α–induced vascular cell adhesion molecule-1 (VCAM-1) and intercellular adhesion molecule-1 (ICAM-1) expression in human umbilical vein endothelial cells (HUVECs). In contrast, the synthetic PPARγ ligand pioglitazone weakly induced RORα4 expression but did not affect RORα1 expression or TNF-α–induced gene expression. Biphenol A diglycidyl ether, a PPARγ antagonist, did not block the effect of 15d-PGJ2 on RORα expression. Adenovirus-mediated overexpression of RORα1 inhibited TNF-α–induced VCAM-1 and ICAM-1 expression, and overexpression of a mutant form of RORα1 (RORα1Δ), which inhibited transcriptional activity of RORα1 and RORα4, attenuated its inhibition. Furthermore, we found that RORα1Δ attenuated the inhibitory actions of 15d-PGJ2 on TNF-α–induced VCAM-1 and ICAM-1 expression.

Conclusions—These results suggest that 15d-PGJ2 inhibits TNF-α–induced expression of proinflammatory genes mediated in part via induction of RORα in HUVECs. This mechanism provides a novel insight into PPARγ-independent actions of 15d-PGJ2.
Leukocytosis and Ischemic Vascular Disease Morbidity and Mortality
Authors: Coller Barry S.
Published: January 2005

The association between leukocytosis and increased morbidity and mortality of ischemic vascular disease has been observed for more than half a century, and recent studies in >350 000 patients confirm the robustness of the association and the dramatically higher relative and absolute acute and chronic mortality rates in patients with high versus low leukocyte counts. Although there is reason to believe that the association is not causal (that is, that leukocytosis is simply a marker of inflammation), there is also reason to believe that the leukocytosis directly enhances acute thrombosis and chronic atherosclerosis. Leukocytosis also is associated with poor prognosis and vaso-occlusive events in patients with sickle cell disease, and experimental data suggest a direct role for leukocytes in microvascular obstruction. The only way to test whether leukocytes contribute directly to poor outcome in ischemic cardiovascular disease is to assess the effect of modifying leukocyte function or number. Because selective blockade of leukocyte integrin αMβ2 and P-selectin have thus far been disappointing as therapeutic strategies in human cardiovascular and cerebrovascular disease, I discuss the potential risks and benefits of short-term treatment with hydroxyurea to decrease the leukocyte count in select populations of patients at the highest risk of short-term death.
Glycogen-Synthase Kinase3β/β-Catenin Axis Promotes Angiogenesis Through Activation of Vascular Endothelial Growth Factor Signaling in Endothelial Cells
Authors: Skurk Carsten , Maatz Henrike , Rocnik Edward , Bialik Ann , Force Thomas , Walsh Kenneth
Published: January 2005

Glycogen-Synthase Kinase 3β (GSK3β) has been shown to function as a nodal point of converging signaling pathways in endothelial cells to regulate vessel growth, but the signaling mechanisms downstream from GSK3β have not been identified. Here, we show that β-catenin is an important downstream target for GSK3β action in angiogenesis and dissect the signal transduction pathways involved in the angiogenic phenotype. Transduction of human umbilical vein endothelial cells (HUVECs) with a kinase-mutant form of the enzyme (KM-GSK3β) increased cytosolic β-catenin levels, whereas constitutively active GSK3β (S9A-GSK3β) reduced β-catenin levels. Lymphoid enhancer factor/T-cell factor promoter activity was upregulated by KM-GSK3β and diminished by S9A-GSK3β, whereas manipulation of Akt signaling had no effect on this parameter. β-Catenin transduction induced capillary formation in a Matrigel-plug assay in vivo and promoted endothelial cell differentiation into network structures on Matrigel-coated plates in vitro. β-Catenin activated the expression of vascular endothelial growth factor (VEGF)-A and VEGF-C in endothelial cells, and these effects were mediated at the levels of protein, mRNA, and promoter activity. Consistent with these data, β-catenin increased the phosphorylation of the VEGF receptor 2 (VEGF-R2) and promoted its association with PI3-kinase, leading to a dose-dependent activation of the serine–threonine kinase Akt. Inhibition of PI3-kinase or Akt signaling led to a significant reduction in the pro-angiogenic activity of β-catenin. Collectively, these data show that the growth factor–PI3-kinase–Akt axis functions downstream of GSK3β/β-catenin signaling in endothelial cells to promote angiogenesis.
Induced Deletion of the
N-Cadherin
Gene in the Heart Leads to Dissolution of the Intercalated Disc Structure
Authors: Kostetskii Igor , Li Jifen , Xiong Yanming , Zhou Rong , Ferrari Victor A. , Patel Vickas V. , Molkentin Jeffery D. , Radice Glenn L.
Published: January 2005

The structural integrity of the heart is maintained by the end-to-end connection between the myocytes called the intercalated disc. The intercalated disc contains different junctional complexes that enable the myocardium to function as a syncytium. One of the junctional complexes, the zonula adherens or adherens junction, consists of the cell adhesion molecule, N-cadherin, which mediates strong homophilic cell–cell adhesion via linkage to the actin cytoskeleton. To determine the function of N-cadherin in the working myocardium, we generated a conditional knockout containing loxP sites flanking exon 1 of the
N-cadherin
(
Cdh2
) gene. Using a cardiac-specific tamoxifen-inducible Cre transgene,
N-cadherin
was deleted in the adult myocardium. Loss of N-cadherin resulted in disassembly of the intercalated disc structure, including adherens junctions and desmosomes. The mutant mice exhibited modest dilated cardiomyopathy and impaired cardiac function, with most animals dying within two months after tamoxifen administration. Decreased sarcomere length and increased Z-line thickness were observed in the mutant hearts consistent with loss of muscle tension because N-cadherin was no longer available to anchor myofibrils at the plasma membrane. Ambulatory electrocardiogram monitoring captured the abrupt onset of spontaneous ventricular tachycardia, confirming that the deaths were arrhythmic in nature. A significant decrease in the gap junction protein, connexin 43, was observed in the N-cadherin–depleted hearts. This animal model provides the first demonstration of the hierarchical relationship of the structural components of the intercalated disc in the working myocardium, thus establishing N-cadherin’s paramount importance in maintaining the structural integrity of the heart.
Increased PI3-Kinase in Presympathetic Brain Areas of the Spontaneously Hypertensive Rat
Authors: Veerasingham Shereeni J. , Yamazato Masanobu , Berecek Kathleen H. , Wyss J. Michael , Raizada Mohan K.
Published: January 2005

Existing evidence led us to hypothesize that increases in p85α, a regulatory subunit of PI3-kinase, in presympathetic brain areas contribute to hypertension. PI3-kinase p85α, p110α, and p110δ mRNA was 1.5- to 2-fold higher in the paraventricular nucleus (PVN) of spontaneously hypertensive rats (SHR) compared with their controls, Wistar Kyoto rats (WKY). The increase in p85α/p110δ was attenuated in SHR treated with captopril, an angiotensin (Ang)-converting enzyme inhibitor, from in utero to 6 months of age. In the rostral ventrolateral medulla (RVLM), p110δ mRNA was ≈2-fold higher in SHR than in WKY. Moreover, the increases in mRNA were associated with higher PI3-kinase activity in both nuclei. The functional relevance was studied in neuronal cultures because SHR neurons reflect the augmented p85α mRNA and PI3-kinase activity. Expression of a p85 dominant-negative mutant decreased norepinephrine (NE) transporter mRNA and [
3
H]NE uptake by ≈60% selectively in SHR neurons. In summary, increased p85α/p110δ expression in the PVN and RVLM is associated with increased PI3-kinase activity in the SHR. Furthermore, normalized PI3-kinase p85α/p110δ expression within the PVN might contribute to the overall effect of captopril, perhaps attributable to a consequent decrease in NE availability.
Vascular Endothelial–Cadherin Tyrosine Phosphorylation in Angiogenic and Quiescent Adult Tissues
Authors: Lambeng Nathalie , Wallez Yann , Rampon Christine , Cand Francine , Christé Georges , Gulino-Debrac Danielle , Vilgrain Isabelle , Huber Philippe
Published: January 2005

Vascular endothelial–cadherin (VE-cadherin) plays a key role in angiogenesis and in vascular permeability. The regulation of its biological activity may be a central mechanism in normal or pathological angiogenesis. VE-cadherin has been shown to be phosphorylated on tyrosine in vitro under various conditions, including stimulation by VEGF. In the present study, we addressed the question of the existence of a tyrosine phosphorylated form of VE-cadherin in vivo, in correlation with the quiescent versus angiogenic state of adult tissues. Phosphorylated VE-cadherin was detected in mouse lung, uterus, and ovary but not in other tissues unless mice were injected with peroxovanadate to block protein phosphatases. Remarkably, VE-cadherin tyrosine phosphorylation was dramatically increased in uterus and ovary, and not in other organs, during PMSG/hCG-induced angiogenesis. In parallel, we observed an increased association of VE-cadherin with Flk1 (VEGF receptor 2) during hormonal angiogenesis. Additionally, Src kinase was constitutively associated with VE-cadherin in both quiescent and angiogenic tissues and increased phosphorylation of VE-cadherin–associated Src was detected in uterus and ovary after hormonal treatment. Src-VE-cadherin association was detected in cultured endothelial cells, independent of VE-cadherin phosphorylation state and Src activation level. In this model, Src inhibition impaired VEGF-induced VE-cadherin phosphorylation, indicating that VE-cadherin phosphorylation was dependent on Src activation. We conclude that VE-cadherin is a substrate for tyrosine kinases in vivo and that its phosphorylation, together with that of associated Src, is increased by angiogenic stimulation. Physical association between Flk1, Src, and VE-cadherin may thus provide an efficient mechanism for amplification and perpetuation of VEGF-stimulated angiogenic processes.
Haptoglobin Genotype– and Diabetes-Dependent Differences in Iron-Mediated Oxidative Stress In Vitro and In Vivo
Authors: Asleh Rabea , Guetta Julia , Kalet-Litman Shiri , Miller-Lotan Rachel , Levy Andrew P.
Published: January 2005

We have recently demonstrated in multiple independent population-based longitudinal and cross sectional analyses that the haptoglobin 2-2 genotype is associated with an increased risk for diabetic cardiovascular disease. The chief function of haptoglobin (Hp) is to bind to hemoglobin and thereby prevent hemoglobin-induced oxidative tissue damage. This antioxidant function of haptoglobin is mediated in part by the ability of haptoglobin to prevent the release of iron from hemoglobin on its binding. We hypothesized that there may be diabetes- and haptoglobin genotype–dependent differences in the amount of catalytically active redox active iron derived from hemoglobin. We tested this hypothesis using several complementary approaches both in vitro and in vivo. First, measuring redox active iron associated with haptoglobin-hemoglobin complexes in vitro, we demonstrate a marked increase in redox active iron associated with Hp 2-2-glycohemoglobin complexes. Second, we demonstrate increased oxidative stress in tissue culture cells exposed to haptoglobin 2-2-hemoglobin complexes as opposed to haptoglobin 1-1-hemoglobin complexes, which is inhibitable by desferrioxamine by either a chelation or reduction mechanism. Third, we demonstrate marked diabetes-dependent differences in the amount of redox active iron present in the plasma of mice genetically modified expressing the Hp 2 allele as compared with the Hp 1 allele. Taken together these data implicate redox active iron in the increased susceptibility of individuals with the Hp 2 allele to diabetic vascular disease.
Accessory Kvβ
1
Subunits Differentially Modulate the Functional Expression of Voltage-Gated K
+
Channels in Mouse Ventricular Myocytes
Authors: Aimond Franck , Kwak Seung P. , Rhodes Kenneth J. , Nerbonne Jeanne M.
Published: January 2005

Voltage-gated K
+
(Kv) channel accessory (β) subunits associate with pore-forming Kv α subunits and modify the properties and/or cell surface expression of Kv channels in heterologous expression systems. There is very little presently known, however, about the functional role(s) of Kv β subunits in the generation of native cardiac Kv channels. Exploiting mice with a targeted disruption of the Kvβ
1
gene (Kvβ
1
−/−
), the studies here were undertaken to explore directly the role of Kvβ
1
in the generation of ventricular Kv currents. Action potential waveforms and peak Kv current densities are indistinguishable in myocytes isolated from the left ventricular apex (LVA) of Kvβ
1
−/−
and wild-type (WT) animals. Analysis of Kv current waveforms, however, revealed that mean±SEM
I
to,f
density is significantly (
P
≤0.01) lower in Kvβ
1
−/−
(21.0±0.9 pA/pF; n=68), than in WT (25.3±1.4 pA/pF; n=42), LVA myocytes, and that mean±SEM
I
K,slow
density is significantly (
P
≤0.01) higher in Kvβ
1
−/−
(19.1±0.9 pA/pF; n=68), compared with WT (15.9±0.7 pA/pF; n=42), LVA cells. Pharmacological studies demonstrated that the TEA-sensitive component of
I
K,slow
,
I
K,slow2,
is selectively increased in Kvβ
1
−/−
LVA myocytes. In parallel with the alterations in
I
to,f
and
I
K,slow2
densities, Kv4.3 expression is decreased and Kv2.1 expression is increased in Kvβ
1
−/−
ventricles. Taken together, these results demonstrate that Kvβ
1
differentially regulates the functional cell surface expression of myocardial
I
to,f
and
I
K,slow2
channels.
Action Potential Duration Restitution and Alternans in Rabbit Ventricular Myocytes
Authors: Goldhaber Joshua I. , Xie Lai-Hua , Duong Tan , Motter Christi , Khuu Kien , Weiss James N.
Published: January 2005

Action potential duration (APD) restitution properties and repolarization alternans are thought to be important arrhythmogenic factors. We investigated the role of intracellular calcium (Ca
2+
i
) cycling in regulating APD restitution slope and repolarization (APD) alternans in patch-clamped rabbit ventricular myocytes at 34 to 36°C, using the perforated or ruptured patch clamp techniques with Fura-2-AM to record Ca
2+
i
. When APD restitution was measured by either the standard extrastimulus (S1S2) method or the dynamic rapid pacing method, the maximum APD restitution slope exceeded 1 by both methods, but was more shallow with the dynamic method. These differences were associated with greater Ca
2+
i
accumulation during dynamic pacing. The onset of APD alternans occurred at diastolic intervals at which the APD restitution slope was significantly <1 and was abolished by suppressing sarcoplasmic reticulum (SR) Ca
2+
i
cycling with thapsigargin and ryanodine, or buffering the global Ca
2+
i
transient with BAPTA-AM or BAPTA. Thapsigargin and ryanodine flattened APD restitution slope to <1 when measured by the dynamic method, but not by the S1S2 method. BAPTA-AM or BAPTA failed to flatten APD restitution slope to <1 by either method. In conclusion, APD alternans requires intact Ca
2+
i
cycling and is not reliably predicted by APD restitution slope when Ca
2+
i
cycling is suppressed. Ca
2+
i
cycling may contribute to differences between APD restitution curves measured by S1S2 versus dynamic pacing protocols by inducing short-term memory effects related to pacing-dependent Ca
2+
i
accumulation.
Phenytoin Exposure Is Associated With Functional and Cognitive Disability After Subarachnoid Hemorrhage
Authors: Naidech Andrew M. , Kreiter Kurt T. , Janjua Nazli , Ostapkovich Noeleen , Parra Augusto , Commichau Christopher , Connolly E. Sander , Mayer Stephan A. , Fitzsimmons Brian-Fred M.
Published: January 2005

Background and Purpose—

Phenytoin (PHT) is routinely used for seizure prophylaxis after subarachnoid hemorrhage (SAH), but may adversely affect neurologic and cognitive recovery.

Methods—

We studied 527 SAH patients and calculated a “PHT burden” for each by multiplying the average serum level of PHT by the time in days between the first and last measurements, up to a maximum of 14 days from ictus. Functional outcome at 14 days and 3 months was measured with the modified Rankin scale, with poor functional outcome defined as dependence or worse (modified Rankin Scale ≥4). We assessed cognitive outcomes at 14 days and 3 months with the telephone interview for cognitive status.

Results—

PHT burden was associated with poor functional outcome at 14 days (OR, 1.5 per quartile; 95% CI, 1.3 to 1.8;
P
<0.001), although not at 3 months (
P
=0.09); the effect remained (OR, 1.6 per quartile; 95% CI, 1.2 to 2.1;
P
<0.001) after correction for admission Glasgow Coma Scale, fever, stroke, age, National Institutes of Health Stroke Scale ≥10, hydrocephalus, clinical vasospasm, and aneurysm rebleeding. Seizure in hospital (OR, 4.1; 95% CI, 1.5 to 11.1;
P
=0.002) was associated with functional disability in a univariate model only. Higher quartiles of PHT burden were associated with worse telephone interview for cognitive status scores at hospital discharge (
P
<0.001) and at 3 months (
P
=0.003).

Conclusions—

Among patients treated with PHT, burden of exposure to PHT predicts poor neurologic and cognitive outcome after SAH.
Public Awareness of Warning Symptoms, Risk Factors, and Treatment of Stroke in Northwest India
Authors: Pandian Jeyaraj D. , Jaison Ashish , Deepak Sukhbinder S. , Kalra Guneet , Shamsher Shivali , Lincoln Douglas J. , Abraham George
Published: January 2005

Background and Purpose—

This study assessed public awareness of warning symptoms, risk factors, and treatment of stroke in Ludhiana, Punjab, North West India.

Methods—

A hospital-based survey was conducted between February 2002 and September 2002 by the Stroke section of Christian Medical College. The study subjects were relatives of patients without history of stroke, attending the outpatient department of the hospital. Trained medical students, interns, and a nurse interviewed subjects using a structured, pretested, open-ended questionnaire.

Results—

Nine hundred forty-two individuals were interviewed during the study period (56.4% men, mean age 40.1 years, age range 15 to 80 years). Forty-five percent of the subjects did not recognize the brain as the affected organ in stroke. In the multivariate analysis, higher education (
P
<0.001; odds ratio 2.6; 95%, CI 1.8 to 3.8) and upper socioeconomic status (
P
<0.005; odds ratio 1.6; CI, 1.1 to 2.2) correlated with a better knowledge of which organ was affected in stroke. Twenty-three percent of the participants did not know a single warning symptom of stroke. Twenty-one percent of the subjects could not identify even a single risk factor for stroke. Seven percent of the study population believed that oil massage would improve stroke victims. A small proportion of subjects believed in witchcraft, faith healing, homeopathic, and ayurvedic treatment (3%).

Conclusions—

This hospital-based survey reveals a better awareness of stroke warning signs and risk factors. However, knowledge regarding the organ involved, etiology, and treatment of stroke is lacking. Considerable education is needed to increase public awareness in modern concepts of stroke treatment.