bluuebunny/crossref_metadata_2025 huggingface dataset:
Duplex PCR To Differentiate between
Mycoplasma synoviae
and
Mycoplasma gallisepticum
on the Basis of Conserved Species-Specific Sequences of Their Hemagglutinin Genes
Authors: Ben Abdelmoumen Mardassi B. , Ben Mohamed R. , Gueriri I. , Boughattas S. , Mlik B.
Published: February 2005

We developed a duplex PCR assay targeting the hemagglutinin multigene families, vlhA and pMGA, of
Mycoplasma synoviae
and
Mycoplasma gallisepticum
, respectively. The assay proved to be specific and sensitive enough to justify its use for the simultaneous detection of the two major avian mycoplasma species from field isolates.
Rapid Diagnosis of Herpes Simplex Virus Infection by a Loop-Mediated Isothermal Amplification Method
Authors: Enomoto Yoshihiko , Yoshikawa Tetsushi , Ihira Masaru , Akimoto Shiho , Miyake Fumi , Usui Chie , Suga Sadao , Suzuki Kayoko , Kawana Takashi , Nishiyama Yukihiro , Asano Yoshizo
Published: February 2005

Primers for herpes simplex virus type 1 (HSV 1)-specific loop-mediated isothermal amplification (LAMP) method amplified HSV-1 DNA, while HSV-2-specific primers amplified only HSV-2 DNA; no LAMP products were produced by reactions performed with other viral DNAs. The sensitivities of the HSV-1- and HSV-2-specific LAMP methods, determined by agarose gel electrophoresis, reached 500 and 1,000 copies/tube, respectively. The turbidity assay, however, determined the sensitivity of the HSV-1- and HSV-2-specific LAMP methods to be 1,000 and 10,000 copies/tube, respectively. After initial validation studies, 18 swab samples (in sterilized water) collected from patients with either gingivostomatitis or vesicular skin eruptions were examined. HSV-1 LAMP products were detected by agarose gel electrophoresis in the 10 samples that also demonstrated viral DNA detection by real-time PCR. Nine of these 10 samples exhibited HSV-1 LAMP products by turbidity assay. Furthermore, both the agarose gel electrophoresis and the turbidity assay directly detected HSV-1 LAMP products in 9 of the 10 swab samples collected in sterilized water. Next, we examined the reliability of HSV type-specific LAMP for the detection of viral DNA in clinical specimens (culture medium) collected from genital lesions. HSV-2 was isolated from all of the samples and visualized by either agarose gel electrophoresis or turbidity assay.
Identification and Characterization of Clinical Isolates of Members of the
Staphylococcus sciuri
Group
Authors: Stepanović Srdjan , Dakić Ivana , Morrison Donald , Hauschild Tomasz , Ježek Petr , Petráš Petr , Martel An , Vuković Dragana , Shittu Adebayo , Devriese Luc A.
Published: February 2005

A total of 28 staphylococcal isolates from human clinical specimens belonging to the
Staphylococcus sciuri
group were identified and characterized. The API Staph and ID32 STAPH correctly identified
S. sciuri
and
S. lentus
but not
S. vitulinus
strains. Identification to the subspecies level was possible only by a PCR-based method.
Identification and First Report of
Inonotus
(
Phellinus
)
tropicalis
as an Etiologic Agent in a Patient with Chronic Granulomatous Disease
Authors: Sutton D. A. , Thompson E. H. , Rinaldi M. G. , Iwen P. C. , Nakasone K. K. , Jung H. S. , Rosenblatt H. M. , Paul M. E.
Published: February 2005

Although isolates of filamentous basidiomycetes can usually be recognized in a clinical laboratory setting, identification is problematic, as they seldom exhibit diagnostic morphological features formed in nature. This paper is the first report of
Inonotus
(
Phellinus
)
tropicalis
inciting human disease and describes the methods used to support the identification.
Liver Abscess Caused by
magA
+
Klebsiella pneumoniae
in North America
Authors: Fang Ferric C. , Sandler Netanya , Libby Stephen J.
Published: February 2005

Taiwan has witnessed an emerging syndrome of liver abscess caused by
Klebsiella pneumoniae
carrying the
magA
gene required for exopolysaccharide web biosynthesis. We report a patient transferred from Alaska to Washington State with a
magA
+
K. pneumoniae
liver abscess and describe a simple approach for recognition of these hypervirulent strains.
Isolation of an Influenza C Virus Introduced into Japan by a Traveler from Malaysia
Authors: Matsuzaki Yoko , Sato Katsuhiko , Sugawara Kanetsu , Takashita Emi , Muraki Yasushi , Morishita Takayuki , Kumagai Norimichi , Suzuki Sousuke , Hongo Seiji
Published: February 2005

An influenza C virus was isolated from a Japanese traveler who had visited Malaysia in April 1999. Phylogenetic analysis indicated that the genome composition of this virus was distinct from that of any other strain isolated in Japan. The possibility that a genetically unique influenza C virus was introduced into Japan by a traveler is shown.
Effect of branched-chain fatty acid on lipid dynamics in mice lacking liver fatty acid binding protein gene
Authors: Atshaves Barbara P. , McIntosh Avery L. , Payne H. Ross , Mackie John , Kier Ann B. , Schroeder Friedhelm
Published: February 2005

Although a role for liver fatty acid protein (L-FABP) in the metabolism of branched-chain fatty acids has been suggested based on data obtained with cultured cells, the physiological significance of this observation remains to be demonstrated. To address this issue, the lipid phenotype and metabolism of phytanic acid, a branched-chain fatty acid, were determined in L-FABP gene-ablated mice fed a diet with and without 1% phytol (a metabolic precursor to phytanic acid). In response to dietary phytol, L-FABP gene ablation exhibited a gender-dependent lipid phenotype. Livers of phytol-fed female L-FABP−/− mice had significantly more fatty lipid droplets than male L-FABP−/− mice, whereas in phytol-fed wild-type L-FABP+/+ mice differences between males and females were not significant. Thus L-FABP gene ablation exacerbated the accumulation of lipid droplets in phytol-fed female, but not male, mice. These results were reflected in the lipid profile, where hepatic levels of triacylglycerides in phytol-fed female L-FABP−/− mice were significantly higher than in male L-FABP−/− mice. Furthermore, livers of phytol-fed female L-FABP−/− mice exhibited more necrosis than their male counterparts, consistent with the accumulation of higher levels of phytol metabolites (phytanic acid, pristanic acid) in liver and serum, in addition to increased hepatic levels of sterol carrier protein (SCP)-x, the only known peroxisomal enzyme specifically required for branched-chain fatty acid oxidation. In summary, L-FABP gene ablation exerted a significant role, especially in female mice, in branched-chain fatty acid metabolism. These effects were only partially compensated by concomitant upregulation of SCP-x in response to L-FABP gene ablation and dietary phytol.
Caveolin-1 in oncogenic transformation, cancer, and metastasis
Authors: Williams Terence M. , Lisanti Michael P.
Published: February 2005

Caveolae are 50- to 100-nm omega-shaped invaginations of the plasma membrane that function as regulators of signal transduction. Caveolins are a class of oligomeric structural proteins that are both necessary and sufficient for caveolae formation. Interestingly, caveolin-1 has been implicated in the pathogenesis of oncogenic cell transformation, tumorigenesis, and metastasis. Here, we review the available experimental evidence (gleaned from cultured cells, animal models, and human tumor samples) that caveolin-1 (Cav-1) functions as a “tumor and/or metastasis modifier gene.” Genetic evidence from the study of Cav-1(−/−) null mice and human breast cancer mutations [CAV-1 (P132L)] supports the idea that caveolin-1 normally functions as a negative regulator of cell transformation and mammary tumorigenesis. In contrast, caveolin-1 may function as a tumor promoter in prostate cancers. We discuss possible molecular mechanisms to explain these intriguing, seemingly opposing, findings. More specifically, caveolin-1 phosphorylation (at Tyr14 and Ser80) and mutations (P132L) may override or inactivate the growth inhibitory activity of the caveolin-scaffolding domain (residues 82–101).
The mechanical basis of impaired esophageal emptying postfundoplication
Authors: Ghosh Sudip K. , Kahrilas Peter J. , Zaki Tamer , Pandolfino John E. , Joehl Raymond J. , Brasseur James G.
Published: February 2005

Fundoplication (FP) efficacy is a trade-off between protection against reflux and postoperative dysphagia from the surgically altered mechanical balance within the esophagogastric segment. The purpose of the study was to contrast quantitatively the mechanical balance between normal and post-FP esophageal emptying. Physiological data were combined with mathematical models based on the laws of mechanics. Seven normal controls (NC) and seven post-FP patients underwent concurrent manometry and fluoroscopy. Temporal changes in geometry of the distal bolus cavity and hiatal canal, and cavity-driving pressure were quantified during emptying. Mathematical models were developed to couple cavity pressure to hiatal geometry and esophageal emptying and to determine cavity muscle tone. We found that the average length of the hiatal canal post-FP was twice that of NC; reduction of hiatal radius was not significant. All esophageal emptying events post-FP were incomplete (51% retention); there was no significant difference in the period of emptying between NC and post-FP, and average emptying rates were 40% lower post-FP. The model predicted three distinct phases during esophageal emptying: hiatal opening ( phase I), a quasi-steady period ( phase II), and final emptying ( phase III). A rapid increase in muscle tone and driving pressure forced normal hiatal opening. Post-FP there was a severe impairment of cavity muscle tone causing deficient hiatal opening and flow and bolus retention. We conclude that impaired esophageal emptying post-FP follows from the inability of distal esophageal muscle to generate necessary tone rapidly. Immobilization of the intrinsic sphincter by the surgical procedure may contribute to this deficiency, impaired emptying, and possibly, dysphagia.
Polyamines are necessary for synthesis and stability of occludin protein in intestinal epithelial cells
Authors: Guo Xin , Rao Jaladanki N. , Liu Lan , Zou Tongtong , Keledjian Kaspar M. , Boneva Dessy , Marasa Bernard S. , Wang Jian-Ying
Published: February 2005

Occludin is an integral membrane protein that forms the sealing element of tight junctions and is critical for epithelial barrier function. Polyamines are implicated in multiple signaling pathways driving different biological functions of intestinal epithelial cells (IEC). The present study determined whether polyamines are involved in expression of occludin and play a role in intestinal epithelial barrier function. Studies were conducted in stable Cdx2-transfected IEC-6 cells (IEC-Cdx2L1) associated with a highly differentiated phenotype. Polyamine depletion by α-difluoromethylornithine (DFMO) decreased levels of occludin protein but failed to affect expression of its mRNA. Other tight junction proteins, zonula occludens (ZO)-1, ZO-2, claudin-2, and claudin-3, were also decreased in polyamine-deficient cells. Decreased levels of tight junction proteins in DFMO-treated cells were associated with dysfunction of the epithelial barrier, which was overcome by exogenous polyamine spermidine. Decreased levels of occludin in polyamine-deficient cells was not due to the reduction of intracellular-free Ca2+concentration ([Ca2+]cyt), because either increased or decreased [Ca2+]cytdid not alter levels of occludin in the presence or absence of polyamines. The level of newly synthesized occludin protein was decreased by ∼70% following polyamine depletion, whereas its protein half-life was reduced from ∼120 min in control cells to ∼75 min in polyamine-deficient cells. These findings indicate that polyamines are necessary for the synthesis and stability of occludin protein and that polyamine depletion disrupts the epithelial barrier function, at least partially, by decreasing occludin.
Treatment with bindarit, a blocker of MCP-1 synthesis, protects mice against acute pancreatitis
Authors: Bhatia Madhav , Ramnath Raina Devi , Chevali Lakshmi , Guglielmotti Angelo
Published: February 2005

Chemokines are believed to play a key role in the pathogenesis of acute pancreatitis. We have earlier shown that pancreatic acinar cells produce the chemokine monocyte chemotactic protein (MCP)-1 in response to caerulein hyperstimulation, demonstrating that acinar-derived MCP-1 is an early mediator of inflammation in acute pancreatitis. Blocking chemokine production or action is a major target for pharmacological intervention in a variety of inflammatory diseases, such as acute pancreatitis. 2-Methyl-2-[[1-(phenylmethyl)-1H-indazol-3yl]methoxy]propanoic acid (bindarit) has been shown to preferentially inhibit MCP-1 production in vitro in monocytes and in vivo without affecting the production of the cytokines IL-1, IL-6, or the chemokines IL-8, protein macrophage inflammatory-1α, and RANTES. The present study aimed to define the role of MCP-1 in acute pancreatitis with the use of bindarit. In a model of acute pancreatitis induced by caerulein hyperstimulation, prophylactic as well as therapeutic treatment with bindarit significantly reduced MCP-1 levels in the pancreas. Also, this treatment significantly protected mice against acute pancreatitis as evident by attenuated hyperamylasemia neutrophil sequestration in the pancreas (pancreatic MPO activity), and pancreatic acinar cell injury/necrosis on histological examination of pancreas sections.
Mechanical traumatic injury without circulatory shock causes cardiomyocyte apoptosis: role of reactive nitrogen and reactive oxygen species
Authors: Tao Ling , Liu Hui-Rong , Gao Feng , Qu Yan , Christopher Theodore A. , Lopez Bernard L. , Ma Xin L.
Published: February 2005

Apoptotic cell death plays a critical role in tissue injury and organ dysfunction under a variety of pathological conditions. The present study was designed to determine whether apoptosis may contribute to posttraumatic cardiac dysfunction, and if so, to investigate the mechanisms involved. Male adult mice were subjected to nonlethal traumatic injury, and cardiomyocyte apoptosis, cardiac function, and cardiac production of reactive oxygen/nitrogen species were determined. Modified Noble-Collip drum trauma did not result in circulatory shock, and the 24-h survival rate was 100%. No direct mechanical traumatic injury was observed in the heart immediately after trauma. However, cardiomyocyte apoptosis gradually increased and reached a maximal level 12 h after trauma. Significantly, cardiac dysfunction was observed 24 h after trauma in the isolated perfused heart. This was completely reversed when apoptosis was blocked by administration of a nonselective caspase inhibitor immediately after trauma. In the traumatized hearts, reactive nitrogen species (e.g., nitric oxide) and reactive oxygen species (e.g., superoxide) were both significantly increased, and maximal nitric oxide production preceded maximal apoptosis. Moreover, a highly cytotoxic reactive species, peroxynitrite, was markedly increased in the traumatic heart, and there was a significant positive correlation between cardiac nitrotyrosine content and caspase 3 activity. Our present study demonstrated for the first time that nonlethal traumatic injury caused delayed cell death and that apoptotic cardiomyocyte death contributes to posttrauma organ dysfunction. Antiapoptotic treatments, such as blockade of reactive nitrogen oxygen species generation, may be novel strategies in reducing posttrauma multiple organ failure.
Effect of 1,1-dimethylphenyl 1,4-piperazinium on mouse tracheal smooth muscle responsiveness
Authors: Dorion G. , Israël-Assayag E. , Beaulieu M. J. , Cormier Y.
Published: February 2005

Bronchial hyperresponsiveness is one of the main features of asthma. A nicotinic receptor agonist, 1,1-dimethylphenyl 1,4-piperazinium (DMPP), has been shown to have an inhibitory effect on airway response to methacholine in an in vivo model of asthma. The aims of this study were to 1) verify whether nicotinic acetylcholine receptors (nAChR) were present on mouse tracheal smooth muscle, 2) verify whether bronchoprotection observed in mice was due to a direct effect on airway smooth muscle, and 3) compare the effects of nicotinic agonists to that of salbutamol. α3-, α4-, and α7-nAChR subunits were detected by immunofluorescence on tracheal tissues from normal BALB/c mice. The effect of DMPP on tracheal responsiveness was verified by an isometric method. Tracheas were isolated from normal mice, placed in organ baths, and contracted with a single dose of methacholine. Cumulative doses of DMPP or salbutamol were added to the baths. Results show that mouse tracheal smooth muscle is positive for α4- and α7-nAChR subunits and that the epithelium is positive for α3-, α4-, and α7-subunits. DMPP induced a greater dose-dependent relaxation of tracheal smooth muscles precontracted with methacholine than with salbutamol. These results suggest that the smooth muscle-relaxing effect of DMPP could have some interest in the treatment of obstructive pulmonary diseases.
Evaluation of interactions between CCK and GLP-1 in their effects on appetite, energy intake, and antropyloroduodenal motility in healthy men
Authors: Brennan Ixchel M. , Feltrin Kate L. , Horowitz Michael , Smout Andre J. P. M. , Meyer James H. , Wishart Judith , Feinle-Bisset Christine
Published: February 2005

There is evidence that CCK and glucagon-like peptide-1 (GLP-1) mediate the effects of nutrients on appetite and gastrointestinal function and that their interaction may be synergistic. We hypothesized that intravenous CCK-8 and GLP-1 would have synergistic effects on appetite, energy intake, and antropyloroduodenal (APD) motility. Nine healthy males (age 22 ± 1 yr) were studied on four separate days in a double-blind, randomized fashion. Appetite and APD pressures were measured during 150-min intravenous infusions of 1) isotonic saline (control), 2) CCK-8 (1.8 pmol·kg−1·min−1), 3) GLP-1 (0.9 pmol·kg−1·min−1), or 4) both CCK-8 (1.8 pmol·kg−1·min−1) and GLP-1 (0.9 pmol·kg−1·min−1). At 120 min, energy intake at a buffet meal was quantified. CCK-8, but not GLP-1, increased fullness, decreased desire to eat and subsequent energy intake, and increased the number and amplitude of isolated pyloric pressure waves and basal pyloric pressure ( P < 0.05). Both CCK-8 and GLP-1 decreased the number of antral and duodenal pressure waves (PWs) ( P < 0.05), and CCK-8+GLP-1 decreased the number of duodenal PWs more than either CCK-8 or GLP-1 alone ( P < 0.02). This was not the case for appetite or isolated pyloric PWs. In conclusion, at the doses evaluated, exogenously administered CCK-8 and GLP-1 had discrepant effects on appetite, energy intake, and APD pressures, and the effects of CCK-8+GLP-1, in combination, did not exceed the sum of the effects of CCK-8 and GLP-1, providing no evidence of synergism.
Relationship between intracellular Po2 recovery kinetics and fatigability in isolated single frog myocytes
Authors: Kindig Casey A. , Walsh Brandon , Howlett Richard A. , Stary Creed M. , Hogan Michael C.
Published: February 2005

In single frog skeletal myocytes, a linear relationship exists between “fatigability” and oxidative capacity. The purpose of this investigation was to study the relationship between the intracellular Po2 (PiO2) offset kinetics and fatigability in single Xenopus laevis myocytes to test the hypothesis that PiO2 offset kinetics would be related linearly with myocyte fatigability and, by inference, oxidative capacity. Individual myocytes ( n = 30) isolated from lumbrical muscle were subjected to a 2-min bout of isometric peak tetanic contractions at either 0.25- or 0.33-Hz frequency while PiO2 was measured continuously via phosphorescence quenching techniques. The mean response time (MRT; time to 63% of the overall response) for PiO2 recovery from contracting values to resting baseline was calculated. After the initial square-wave constant-frequency contraction trial, each cell performed an incremental contraction protocol [i.e., frequency increase every 2 min from 0.167, 0.25, 0.33, 0.5, 1.0, and 2.0 Hz until peak tension fell below 50% of initial values (TTF)]. TTF values ranged from 3.39 to 10.04 min for the myocytes. The PiO2 recovery MRT ranged from 26 to 146 s. A significant ( P < 0.05), negative relationship (MRT = −12.68TTF + 168.3, r2 = 0.605) between TTF and PiO2 recovery MRT existed. These data demonstrate a significant correlation between fatigability and oxidative phosphorylation recovery kinetics consistent with the notion that oxidative capacity determines, in part, the speed with which skeletal muscle can recover energetically to alterations in metabolic demand.
Measuring peripheral resistance and conduit arterial structure in humans using Doppler ultrasound
Authors: Naylor Louise H. , Weisbrod Cara J. , O'Driscoll Gerry , Green Daniel J.
Published: February 2005

The purpose of this study was to establish valid indexes of conduit and resistance vessel structure in humans by using edge detection and wall tracking of high-resolution B-mode arterial ultrasound images, combined with synchronized Doppler waveform envelope analysis, to calculate conduit artery blood flow and diameter continuously across the cardiac cycle. Nine subjects aged 36.7 (9.2) yr underwent, on separate days, assessment of brachial artery blood flow and diameter response to 5-, 10-, and 15-min periods of forearm ischemia in the presence and absence of combined sublingual glyceryl trinitrate (GTN) administration. Two further sessions examined responses to ischemic exercise, one in combination with GTN. The peak brachial artery diameter was observed in response to the combination of ischemic exercise and GTN; a significant difference existed between resting brachial artery diameter and peak brachial artery diameter, indicating that resting diameter may be a poor measure of conduit vessel structure in vivo. Peak brachial artery flow was also observed in response to a combination of forearm ischemia exercise and GTN administration, the response being greater than that induced by periods of ischemia, GTN, or ischemic exercise alone. These data indicate that noninvasive indexes of conduit and resistance vessel structure can be simultaneously determined in vivo in response to a single, brief, stimulus and that caution should be applied in using resting arterial diameter as a surrogate measure of conduit artery structure in vivo.
Amino acid supplementation alters bone metabolism during simulated weightlessness
Authors: Zwart S. R. , Davis-Street J. E. , Paddon-Jones D. , Ferrando A. A. , Wolfe R. R. , Smith S. M.
Published: February 2005

High-protein and acidogenic diets induce hypercalciuria. Foods or supplements with excess sulfur-containing amino acids increase endogenous sulfuric acid production and therefore have the potential to increase calcium excretion and alter bone metabolism. In this study, effects of an amino acid/carbohydrate supplement on bone resorption were examined during bed rest. Thirteen subjects were divided at random into two groups: a control group (Con, n = 6) and an amino acid-supplemented group (AA, n = 7) who consumed an extra 49.5 g essential amino acids and 90 g carbohydrate per day for 28 days. Urine was collected for n-telopeptide (NTX), deoxypyridinoline (DPD), calcium, and pH determinations. Bone mineral content was determined and potential renal acid load was calculated. Bone-specific alkaline phosphatase was measured in serum samples collected on day 1 (immediately before bed rest) and on day 28. Potential renal acid load was higher in the AA group than in the Con group during bed rest ( P < 0.05). For all subjects, during bed rest urinary NTX and DPD concentrations were greater than pre-bed rest levels ( P < 0.05). Urinary NTX and DPD tended to be higher in the AA group ( P = 0.073 and P = 0.056, respectively). During bed rest, urinary calcium was greater than baseline levels ( P < 0.05) in the AA group but not the Con group. Total bone mineral content was lower after bed rest than before bed rest in the AA group but not the Con group ( P < 0.05). During bed rest, urinary pH decreased ( P < 0.05), and it was lower in the AA group than the Con group. These data suggest that bone resorption increased, without changes in bone formation, in the AA group.
Hypoadiponectinemia Is Associated With Ischemic Cerebrovascular Disease
Authors: Chen Miao-Pei , Tsai Jack C.-R. , Chung Fu-Mei , Yang Sheng-Shan , Hsing Liang-Lan , Shin Shyi-Jang , Lee Yau-Jiunn
Published: February 2005

Objective—

Adiponectin, an adipocyte-derived peptide with antiinflammatory and antiatherogenic effects, is known to protect against the initiation and progression of atherosclerosis. In this study, we investigate whether hypoadiponectinemia is present in patients with ischemic cerebrovascular disease (CVD).

Methods and Results—

In this case-control study, plasma adiponectin concentration was measured by an enzyme-linked immunosorbent assay in type 2 diabetic and nondiabetic subjects with or without ischemic CVD. A total of 534 subjects were studied. The mean plasma level of adiponectin of the 228 patients with ischemic CVD was significantly lower than that of 306 subjects without CVD. When the analysis was stratified according to diabetes status, plasma levels of adiponectin in CVD subjects with or without type 2 diabetes were significantly lower than those of their counterparts. Decreasing concentrations of adiponectin were independently and significantly associated with a higher risk of CVD when concentrations were analyzed by quartile and as a continuous variable. When patients with CVD were subgrouped according to the comorbidity with or without type2 diabetes, the same trend of association between plasma adiponectin and risk of CVD was observed in each group.

Conclusion—

These data show that there are significantly lower levels of plasma adiponectin in patients with ischemic CVD.
Physical Inactivity Increases Oxidative Stress, Endothelial Dysfunction, and Atherosclerosis
Authors: Laufs Ulrich , Wassmann Sven , Czech Thomas , Münzel Thomas , Eisenhauer Marco , Böhm Michael , Nickenig Georg
Published: February 2005

Objective—

Sedentary lifestyle is associated with increased cardiovascular events. The underlying molecular mechanisms are incompletely understood. Reactive oxygen species (ROS) contribute to endothelial dysfunction and atherosclerosis. An important source of vascular ROS is the NADPH oxidase.

Methods and Results—

C57BL6 mice were subjected to regular housing (physical inactivity) or voluntary training on running wheels (6 weeks). Inactivity increased vascular lipid peroxidation to 148±9% and upregulated superoxide release to 176±17% (L-012 chemiluminescence) and 188±29% (cytochrome C reduction assay), respectively. ROS production was predominantly increased in the endothelium and the media (dihydroethidium fluorescence). Activity of the NADPH oxidase was increased to 154±22% in the sedentary group. Rac1 GST-PAK pull-down assays showed an upregulation of rac1 activity to 161±14%. Expression levels of the subunits nox1, p47phox, and p67phox were increased. To address the significance of the antioxidative effects of running, experiments were repeated in apolipoprotein E–deficient mice treated with a high-cholesterol diet. Inactivity increased vascular superoxide production and impaired endothelium-dependent vasorelaxation. Atherosclerotic lesion formation was significantly accelerated in sedentary mice.

Conclusions—

Inactivity increases vascular NADPH oxidase expression and activity and enhances vascular ROS production, which contributes to endothelial dysfunction and atherosclerosis during sedentary as opposed to physically active lifestyle.
High Serum Levels of Advanced Glycation End Products Predict Increased Coronary Heart Disease Mortality in Nondiabetic Women but not in Nondiabetic Men
Authors: Kilhovd Bente K. , Juutilainen Auni , Lehto Seppo , Rönnemaa Tapani , Torjesen Peter A. , Birkeland Kåre I. , Berg Tore J. , Hanssen Kristian F. , Laakso Markku
Published: February 2005

Background—

Advanced glycation end products (AGEs), modification products of glycation or glycoxidation of proteins and lipids, have been linked to premature atherosclerosis in patients with diabetes as well as in nondiabetic subjects.

Methods and Results—

Serum levels of AGEs were measured with an immunoassay in samples obtained at baseline examination of a random sample of 1141 nondiabetic individuals (535 men and 606 women), aged 45 to 64 years, living in Kuopio, East Finland, or Turku, West Finland in 1982 to 1984. After 18 years of follow-up, all-cause mortality, cardiovascular disease (CVD), and coronary heart disease (CHD) mortality were registered on the basis of copies of death certificates. Multivariate Cox regression model showed a significant association of serum AGEs with all-cause (
P
=0.012), CVD (
P
=0.018), and CHD (
P
=0.008) mortality in women but not in men. Fasting serum AGEs in the highest quartile were an independent risk factor for all-cause (hazards ratio [HR], 1.90; 95% CI, 1.16 to 3.11;
P
=0.011) and CHD (HR, 6.51; 95% CI, 1.78 to 23.79;
P
=0.005) mortality in women, even after the adjustment for confounding factors, including highly sensitive C-reactive protein.

Conclusions—

The present study is the first to show that serum levels of AGEs can predict total, CVD, and CHD mortality in nondiabetic women.
Effect of Oxidation on the Platelet-Activating Properties of Low-Density Lipoprotein
Authors: Korporaal Suzanne J.A. , Gorter Gertie , van Rijn Herman J.M. , Akkerman Jan-Willem N.
Published: February 2005

Objective—Because of the large variation in oxidizing procedures and susceptibility to oxidation of low-density lipoprotein (LDL) and the lack in quantification of LDL oxidation, the role of oxidation in LDL–platelet contact has remained elusive. This study aims to compare platelet activation by native LDL (nLDL) and oxidized LDL (oxLDL).

Methods and Results—After isolation, nLDL was dialyzed against FeSO4to obtain LDL oxidized to well-defined extents varying between 0% and >60%. The oxLDL preparations were characterized with respect to their platelet-activating properties. An increase in LDL oxidation enhances platelet activation via 2 independent pathways, 1 signaling via p38MAPKphosphorylation and 1 via Ca2+mobilization. Between 0% and 15% oxidation, the p38MAPKroute enhances fibrinogen binding induced by thrombin receptor (PAR-1)-activating peptide (TRAP), and signaling via Ca2+is absent. At >30% oxidation, p38MAPKsignaling increases further and is accompanied by Ca2+mobilization and platelet aggregation in the absence of a second agonist. Despite the increase in p38MAPKsignaling, synergism with TRAP disappears and oxLDL becomes an inhibitor of fibrinogen binding. Inhibition is accompanied by binding of oxLDL to the scavenger receptor CD36, which is associated with the fibrinogen receptor, αIIbβ3.

Conclusion—At >30% oxidation, LDL interferes with ligand binding to integrin αIIbβ3, thereby attenuating platelet functions.
Serum Lipid Profiles Poorly Correlate With
Chlamydia pneumoniae
,
Helicobacter pylori
, and Cytomegalovirus Seropositivity in Prospectively Followed-Up Healthy Children
Authors: Volanen Iina , Raitakari Olli T. , Vainionpää Raija , Arffman Martti , Aarnisalo Johanna , Anglé Susanna , Kallio Katariina , Simell Olli
Published: February 2005

Objective—

Chronic
Chlamydia pneumoniae
(
Cpn
),
Helicobacter pylori
(
Hp
), and herpes virus infections have been associated with atherogenic serum lipid profile and an excess of cardiovascular events in adults. Because mechanisms leading to atherosclerosis are active since early childhood, we examined whether
Cpn, Hp
, or cytomegalovirus (CMV) seropositivity relates to serum lipid, lipoprotein, or apolipoprotein concentrations in children. We also looked for factors increasing probability of
Cpn
seropositivity in children.

Methods and Results—

Cpn-
specific IgG and IgA, as well as
Hp-
specific and CMV-specific IgG antibodies were assessed by enzyme immunoassay in 199 apparently healthy children, followed-up from 7 to 11 years of age. Serum lipid profiles were studied at the ages of 7, 9, and 11 years using standard methods. Neither seroconversion to
Cpn
IgG or IgA antibody positivity nor persistent seropositivity for
Cpn, Hp
, or CMV was associated with proatherogenic serum lipid values. Children with siblings were more likely to possess
Cpn
antibodies than children without siblings (IgG: OR, 5.24; 95% CI, 1.63 to 16.82; IgA: OR, 3.32; 95% CI, 1.15 to 9.57).

Conclusions—

These data suggest that contrary to the observations in adults,
Cpn, Hp
, and CMV seropositivity in otherwise healthy children is not associated with disturbances in serum lipid profile.
Novel Role of ARF6 in Vascular Endothelial Growth Factor–Induced Signaling and Angiogenesis
Authors: Ikeda Satoshi , Ushio-Fukai Masuko , Zuo Lian , Tojo Taiki , Dikalov Sergey , Patrushev Nikolay A. , Alexander R. Wayne
Published: February 2005

Vascular endothelial growth factor (VEGF) stimulates endothelial cell (EC) migration and proliferation primarily through the VEGF receptor-2 (VEGFR2). We have shown that VEGF stimulates a Rac1-dependent NAD(P)H oxidase to produce reactive oxygen species (ROS) that are involved in VEGFR2 autophosphorylation and angiogenic-related responses in ECs. The small GTPase ARF6 is involved in membrane trafficking and cell motility; however, its roles in VEGF signaling and physiological responses in ECs are unknown. In this study, we show that overexpression of dominant-negative ARF6 [ARF6(T27N)] almost completely inhibits VEGF-induced Rac1 activation, ROS production, and VEGFR2 autophosphorylation in ECs. Fractionation of caveolae/lipid raft membranes demonstrates that ARF6, Rac1, and VEGFR2 are localized in caveolin-enriched fractions basally. VEGF stimulation results in the release of VEGFR2 from caveolae/lipid rafts and caveolin-1 without affecting localization of ARF6, Rac1, or caveolin-1 in these fractions. The egress of VEGFR2 from caveolae/lipid rafts is contemporaneous with the tyrosine phosphorylation of caveolin-1 (Tyr14) and VEGFR2 and with their association with each other. ARF6(T27N) significantly inhibits both VEGF-induced responses. Immunofluorescence studies show that activated VEGFR2 and phosphocaveolin colocalize at focal complexes/adhesions after VEGF stimulation. Both overexpression of ARF6(T27N) and mutant caveolin-1(Y14F), which cannot be phosphorylated, block VEGF-stimulated EC migration and proliferation. Moreover, ARF6 expression is markedly upregulated in association with an increase in capillary density in a mouse hindlimb ischemia model of angiogenesis. Thus, ARF6 is involved in the temporal-spatial organization of caveolae/lipid rafts– and ROS-dependent VEGF signaling in ECs as well as in angiogenesis in vivo.
A Pilot Dose-Escalation Safety Study of Tenecteplase in Acute Ischemic Stroke
Authors: Haley E. Clarke , Lyden Patrick D. , Johnston Karen C. , Hemmen Thomas M. ,   the TNK in Stroke Investigators
Published: February 2005

Background and Purpose—

Recombinant tissue-type plasminogen activator (rtPA) is the only approved treatment in acute ischemic stroke. However, intracerebral hemorrhage (ICH) occurs in 6.4% of patients treated with rtPA and limits its use. Tenecteplase (TNK) is a modified form of rtPA, with longer half-life and greater fibrin specificity. Patients after myocardial infarction had fewer systemic hemorrhages when treated with TNK compared with rtPA. This open-label, dose-escalation safety study was conducted to develop initial experience with TNK in the treatment of ischemic stroke.

Methods—

Eligible patients were treated with an intravenous bolus infusion of TNK within 3 hours of stroke onset. The dose escalation was conducted in tiers of 25 patients, starting at 0.1 mg/kg, to a planned maximum of 0.6 mg/kg. The primary endpoint was symptomatic intracranial hemorrhage within 36 hours of treatment. All patients were followed-up for 3 months.

Results—

Eighty-eight (88) patients were treated in 4 dosing tiers. In the first 3 tiers (0.1, 0.2, 0.4 mg/kg) of 25 patients each, no symptomatic and 2 (8%), 8 (32%), and 7 (28%) asymptomatic ICHs occurred. Enrollment into the fourth tier at 0.5 mg/kg was closed after 2 of 13 patients (15%) had symptomatic and 3 (23%) had asymptomatic ICHs. Overall, modified Rankin scores at 3 months were similar to those of historical controls treated with rtPA and not significantly different between treatment groups.

Conclusions—

TNK doses of 0.1 to 0.4 mg/kg are safe in ischemic stroke. Future trials are needed to compare the effect of TNK on neurological outcome and safety as compared with rtPA.
Priorities for Clinical Research in Intracerebral Hemorrhage
Authors:   NINDS ICH Workshop Participants
Published: February 2005

Background and Purpose—

Spontaneous intracerebral hemorrhage (ICH) is one of the most lethal stroke types. In December 2003, a National Institute of Neurological Disorders and Stroke (NINDS) workshop was convened to develop a consensus for ICH research priorities. The focus was clinical research aimed at acute ICH in patients.

Methods—

Workshop participants were divided into 6 groups: (1) current state of ICH research; (2) basic science; and (3) imaging, (4) medical, (5) surgical, and (6) clinical methodology. Each group formulated research priorities before the workshop. At the workshop, these were discussed and refined.

Results—

Recent progress in management of hemorrhage growth, intraventricular hemorrhage, and limitations in the benefit of open craniotomy were noted. The workshop identified the importance of developing animal models to reflect human ICH, as well as the phenomena of rebleeding. More human ICH pathology is needed. Real-time, high-field magnets and 3-dimensional imaging, as well as high-resolution tissue probes, are ICH imaging priorities. Trials of acute blood pressure–lowering in ICH and coagulopathy reversal are medical priorities. The exact role of edema in human ICH pathology and its treatment requires intensive study. Trials of minimally invasive surgical techniques including mechanical and chemical surgical adjuncts are critically important. The methodologic challenges include establishing research networks and a multi-specialty approach. Waiver of consent issues and standardizing care in trials are important issues. Encouragement of young investigators from varied backgrounds to enter the ICH research field is critical.

Conclusions—

Increasing ICH research is crucial. A collaborative approach is likely to yield therapies for this devastating form of brain injury.
Efficacy and Safety of Nimodipine in Subcortical Vascular Dementia
Authors: Pantoni Leonardo , del Ser Teodoro , Soglian Andrea G. , Amigoni Silvia , Spadari Giovanni , Binelli Daniela , Inzitari Domenico
Published: February 2005

Background and Purpose—

Evidence of drug efficacy in vascular dementia (VaD) is scanty. Therapeutic trials should address VaD subtypes. We studied the efficacy and safety of the calcium antagonist nimodipine in subcortical VaD.

Methods—

242 patients defined as affected by subcortical VaD based on clinical (ICD-10) and computed tomography criteria were randomized to oral nimodipine 90 mg/d or placebo.

Results—

230 patients (121 nimodipine, mean age 75.2±6.1; 109 placebo, 75.4±6.0) were valid for the intention-to-treat analysis. At 52 weeks, the Sandoz Clinical Assessment Geriatric scale 5-point variation (primary outcome measure) did not differ significantly between the 2 groups. However, patients on nimodipine performed better than placebo patients in lexical production (
P
<0.01) and less frequently showed deterioration (3 or more point-drop versus baseline) on a Mini-Mental State Examination (28.1% versus 50.5%; χ
2
P
<0.01) and Global Deterioration Scale (
P
<0.05). Dropouts and adverse events were all significantly more common among placebo than nimodipine patients, particularly cardiovascular (30 versus 13; RR, 2.26; 95% CI, 1.11 to 4.60) and cerebrovascular events (28 versus 10; RR, 2.48; 95% CI, 1.23 to 4.98), and behavioral disturbances requiring intervention (22 versus 5; RR, 3.88; 95% CI, 1.49 to 10.12). A worst-rank analysis, performed to correct for the effect of the high dropout rate in the placebo group, showed additional significant differences in favor of nimodipine in Set Test and MMSE total scores.

Conclusions—

Nimodipine may be of some benefit in subcortical VaD. Confirming previous results, the safety analysis of this study shows that in this high-risk population, nimodipine might protect against cardiovascular comorbidities.
The Pathophysiology of Watershed Infarction in Internal Carotid Artery Disease
Authors: Momjian-Mayor Isabelle , Baron Jean-Claude
Published: February 2005

Background and Purpose—

In carotid disease, infarcts can occur in the cortical as well as internal watershed (WS), or both. Better understanding the pathophysiology of WS infarcts would guide treatment. Two distinct hypotheses, namely low-flow and micro-embolism, are equally supported by neuropathological and physiological studies. Here we review the evidence regarding the mechanisms for WS stroke in carotid disease and whether they differ between cortical and internal WS infarcts.

Summary of Review—

After a brief account of the anatomy of the WS and the cerebrovascular physiology in circumstances of low perfusion pressure, the literature concerning the mechanisms of WS infarction in carotid disease is reviewed and discussed with emphasis on imaging and ultrasound studies of the cerebral hemodynamics.

Conclusion—

The evidence strongly favors a hemodynamic mechanism for internal WS infarction, especially regarding the so-called rosary-like pattern in the centrum semiovale. However, the relationships between cortical WS infarction and hemodynamic compromise appear more complicated. Thus, although severe hemodynamic compromise appears to underlie combined cortical and internal WS infarction, artery-to-artery embolism may play an important role in isolated cortical WS infarcts. Based on the high prevalence of microembolic signals documented by ultrasound in symptomatic carotid disease, a recent hypothesis postulates that embolism and hypoperfusion play a synergetic role, according to which small embolic material prone to lodge in distal field arterioles would be more likely to result in cortical micro-infarcts when chronic hypoperfusion prevails. Future studies combining imaging of brain perfusion, diffusion-weighted imaging, and ultrasound detection of microembolic signals should help resolve these issues.
Effects of Fosinopril and Pravastatin on Carotid Intima-Media Thickness in Subjects With Increased Albuminuria
Authors: Asselbergs Folkert W. , van Roon Arie M. , Hillege Hans L. , de Jong Paul E. , Gans Reinold O.B. , Smit Andries J. , van Gilst Wiek H.
Published: February 2005

Background and Purpose—

Elevated urinary albumin excretion (UAE) is associated with an increased carotid intima-media thickness (IMT). Because angiotensin-converting enzyme inhibitors as well as statins have been shown to lower UAE and the progression of IMT, we assessed the effects of fosinopril and pravastatin on carotid IMT in subjects with an increased UAE (15 to 300 mg/24 h).

Methods—

IMT was measured at the posterior wall of the left common carotid artery using radio-frequency signal analysis obtained by M-mode ultrasonography. 642 subjects were double-blind randomized to fosinopril 20 mg or matching placebo and to pravastatin 40 mg or matching placebo and were available for intention-to-treat analysis.

Results—

Mean age was 51±11 years, 65% were male, the median UAE was 22.5 (15.5 to 40.8) mg/24 h, and the mean IMT at baseline was 0.77±0.18 mm. The overall progression rate of IMT in 4 years was 0.037±0.006 mm. No significant difference in IMT progression was found between fosinopril, pravastatin, or matching placebo. IMT after 4 years was predicted by IMT at baseline, age, gender, pulse pressure, and low-density lipoprotein cholesterol levels. Furthermore, a higher incidence of clinical events was observed in subjects with an IMT >1 mm after a mean follow-up of 46±7 months (hazard ratio, 3.13; 95% confidence interval, 1.59 to 6.16;
P
=0.001).

Conclusions—

In subjects with an increased UAE, treatment with fosinopril and pravastatin showed no significant effect on carotid IMT. Furthermore, an IMT <1 mm at baseline is an important indicator for event-free survival.
Localized Reversible Reduction of Apparent Diffusion Coefficient in Transient Hypoglycemia-Induced Hemiparesis
Authors: Böttcher J. , Kunze A. , Kurrat C. , Schmidt P. , Hagemann G. , Witte O.W. , Kaiser W.A.
Published: February 2005

Background and Purpose—

The pathophysiology of hypoglycemia shares a common mechanism with cerebral ischemia, but so far, little is known regarding MRI of humans with hypoglycemia.

Methods—

We report a patient with left hemiparesis and dysarthria associated with a blood glucose level of 1.7 mmol/L. The patient recovered completely after glucose infusion.

Results—

The initial diffusion-weighted imaging (DWI) showed increased signal intensities and a reduction of apparent diffusion coefficient (ADC) values localized in the corpus callosum (splenium) and asymmetrically in the corona radiata. After 48 hours, follow-up revealed complete recovery of DWI and ADC signal abnormalities.

Conclusion—

To our knowledge, this is the first presentation of a case with transient hypoglycemia-induced focal neurological deficits revealing completely reversible MRI changes in terms of disturbed DWI and ADC with a peculiar as yet undescribed topography.
Radiographic Measures of Chronic Periodontitis and Carotid Artery Plaque
Authors: Engebretson Steven P. , Lamster Ira B. , Elkind Mitchell S.V. , Rundek Tatjana , Serman Neill J. , Demmer Ryan T. , Sacco Ralph L. , Papapanou Panos N. , Desvarieux Moïse
Published: February 2005

Background and Purpose—

Chronic periodontitis (CP) is associated with stroke and subclinical atherosclerosis, but clinical measurement of CP can be time consuming and invasive. The purpose of this study was to determine whether radiographically assessed CP is associated with nonstenotic carotid artery plaque as an ultrasound measure of subclinical atherosclerosis.

Methods—

Panoramic oral radiographs were obtained from 203 stroke-free subjects ages 54 to 94 during the baseline examination of the Oral Infections and Vascular Disease Epidemiology Study (INVEST). CP exposure among dentate subjects was defined either categorically (periodontal bone loss ≥50% [severe] versus <50% bone loss) or via tertile formation (for dose-response investigation), with edentulous subjects categorized separately. In all subjects, high-resolution B-mode carotid ultrasound was performed. Carotid plaque thickness (CPT) and prevalence (present/absent) were recorded. Covariates included age, sex, smoking, diabetes, hypertension, low-density lipoprotein (LDL) cholesterol, and high-density lipoprotein cholesterol.

Results—

Among dentate subjects with severe periodontal bone loss, mean CPT was significantly greater (1.20±1.00 mm versus 0.73±0.89 mm;
P
=0.003). CPT increased with more severe bone loss (upper versus lower tertile bone loss;
P
=0.049; adjusted for age, sex, and hypertension). This apparent dose-response effect was more evident among never-smokers. In a fully adjusted multivariate logistic regression model, severe periodontal bone loss was associated with a nearly 4-fold increase in risk for the presence of carotid artery plaque (adjusted odds ratio, 3.64; CI, 1.37 to 9.65).

Conclusions—

Severe periodontal bone loss is associated independently with carotid atherosclerosis. Panoramic oral radiographs may thus provide an efficient means to assess CP in studies of atherosclerosis risk.