bluuebunny/crossref_metadata_2025 huggingface dataset:
Noradrenergic Modulation of Activity in a Vocal Control Nucleus In Vitro
Authors: Solis Michele M. , Perkel David J.
Published: December 2005

Norepinephrine (NE) can profoundly modulate sensory processing, but its effect on motor function is less well understood. Birdsong is a learned behavior involving sensory and motor processes that are influenced by NE. A potential site of NE action is the robust nucleus of the arcopallium (RA): RA receives noradrenergic inputs and has adrenergic receptors, and it is a sensorimotor area instrumental to song production. We hypothesized that NE modulates RA neurons, and as a first test, we examined the effect of NE on RA activity in vitro. We recorded spontaneous activity extracellularly from isolated RA neurons in brain slices made from adult male zebra finches. These neurons exhibited regular tonic activity with firing rates averaging 5.5 Hz. Bath application of NE rapidly and reversibly decreased firing for the majority of neurons, to the extent that spontaneous activity was often abolished. This was likely a direct effect on the cell recorded, because it occurred with blockade of fast excitatory and inhibitory synaptic transmission or of all synaptic transmission. The NE-induced suppression involved α2-adrenergic receptors: yohimbine, an antagonist, completely reversed the suppression, and clonidine, an agonist, partially mimicked it. Perforated patch recordings revealed that NE induced a conductance increase in RA neurons; however, this did not prevent cells from firing when stimulated by afferents in HVC. For some neurons, NE application resulted in an increase in signal-to-noise ratio for spikes evoked by HVC stimulation. Thus NE could strongly modulate the spontaneous activity of RA cells, potentially enhancing signals relayed through RA.
WTC deafness Kyoto (dfk): a rat model for extensive investigations ofKcnq1functions
Authors: Gohma Hiroshi , Kuramoto Takashi , Kuwamura Mitsuru , Okajima Ryoko , Tanimoto Noriaki , Yamasaki Ken-ichi , Nakanishi Satoshi , Kitada Kazuhiro , Makiyama Takeru , Akao Masaharu , Kita Toru , Sasa Masashi , Serikawa Tadao
Published: December 2005

KCNQ1 forms K+channels by assembly with regulatory subunit KCNE proteins and plays a key role in the K+homeostasis in a variety of tissues. In the heart, KCNQ1 is coassembled with KCNE1 to produce a cardiac delayed rectifier K+current. In the inner ear, the KCNQ1/KCNE1 complex maintains the high concentration of K+in the endolymph. In the stomach, KCNQ1 is coassembled with KCNE2 to form the K+exflux channel that is essential for gastric acid secretion. In the colon and small intestine, KCNQ1 is coassembled with KCNE3 to play an important role in transepithelial cAMP-stimulated Cl−secretion. For further understanding of Kcnq1 function in vivo, an animal model has been required. Here we reported the identification of a coisogenic Kcnq1 mutant rat, named deafness Kyoto ( dfk), and the characterization of its phenotypes. WTC- dfk rats carried intragenic deletion at the Kcnq1 gene and showed impaired gain of weight, deafness, and imbalance resulting from the marked reduction of endolymph, prolonged QT interval in the electrocardiogram (ECG), and gastric achlorhydria associated with hypertrophic gastric mucosa. Surprisingly, WTC- dfk rats showed hypertension, which suggested that Kcnq1 might be involved in the regulation of blood pressure. These findings suggest that WTC- dfk rats could represent a powerful tool for studying the physiological functions of KCNQ1 and for the establishment of new therapeutic procedures for Kcnq1-related diseases.
Skeletal Muscle Lipid Metabolism in Exercise and Insulin Resistance
Authors: Kiens Bente
Published: December 2005

Lipids as fuel for energy provision originate from different sources: albumin-bound long-chain fatty acids (LCFA) in the blood plasma, circulating very-low-density lipoproteins-triacylglycerols (VLDL-TG), fatty acids from triacylglycerol located in the muscle cell (IMTG), and possibly fatty acids liberated from adipose tissue adhering to the muscle cells. The regulation of utilization of the different lipid sources in skeletal muscle during exercise is reviewed, and the influence of diet, training, and gender is discussed. Major points deliberated are the methods utilized to measure uptake and oxidation of LCFA during exercise in humans. The role of the various lipid-binding proteins in transmembrane and cytosolic transport of lipids is considered as well as regulation of lipid entry into the mitochondria, focusing on the putative role of AMP-activated protein kinase (AMPK), acetyl CoA carboxylase (ACC), and carnitine during exercise. The possible contribution to fuel provision during exercise of circulating VLDL-TG as well as the role of IMTG is discussed from a methodological point of view. The contribution of IMTG for energy provision may not be large, covering ∼10% of total energy provision during fasting exercise in male subjects, whereas in females, IMTG may cover a larger proportion of energy delivery. Molecular mechanisms involved in breakdown of IMTG during exercise are also considered focusing on hormone-sensitive lipase (HSL). Finally, the role of lipids in development of insulin resistance in skeletal muscle, including possible molecular mechanisms involved, is discussed.
Bullying Girls – Changes after Brief Strategic Family Therapy: A Randomized, Prospective, Controlled Trial with One-Year Follow-Up
Authors: Nickel Marius , Luley Johannes , Krawczyk Jakub , Nickel Cerstin , Widermann Christoph , Lahmann Claas , Muehlbacher Moritz , Forthuber Petra , Kettler Christian , Leiberich Peter , Tritt Karin , Mitterlehner Ferdinand , Kaplan Patrick , Pedrosa Gil Francisco , Rother Wolfhardt , Loew Thomas
Published: December 2005

Background: Many girls bully others. They are conspicuous because of their risk-taking behavior, increased anger, problematic interpersonal relationships and poor quality of life. Our aim was to determine the efficacy of brief strategic family therapy (BSFT) for bullying-related behavior, anger reduction, improvement of interpersonal relationships, and improvement of health-related quality of life in girls who bully, and to find out whether their expressive aggression correlates with their distinctive psychological features. Methods: 40 bullying girls were recruited from the general population: 20 were randomly selected for 3 months of BSFT. Follow-up took place 12 months after the therapy had ended. The results of treatment were examined using the Adolescents’ Risk-taking Behavior Scale (ARBS), the State-Trait Anger Expression Inventory (STAXI), the Inventory of Interpersonal Problems (IIP-D), and the SF-36 Health Survey (SF-36). Results: In comparison with the control group (CG) (according to the intent-to-treat principle), bullying behavior in the BSFT group was reduced (BSFT-G from n = 20 to n = 6; CG from n = 20 to n = 18, p = 0.05) and statistically significant changes in all risk-taking behaviors (ARBS), on most STAXI, IIP-D, and SF-36 scales were observed after BSFT. The reduction in expressive aggression (Anger-Out scale of the STAXI) correlated with the reduction on several scales of the ARBS, IIP-D, and SF-36. Follow-up a year later showed relatively stable events. Conclusions: Our findings suggest that bullying girls suffer from psychological and social problems which may be reduced by the use of BSFT. Expressive aggression in girls appears to correlate with several types of risk-taking behavior and interpersonal problems, as well as with health-related quality of life.
Experimental Posterior Perforating Ocular Injury in Rabbit Eyes: Effects of Radiotherapy with or without Intravitreal Cyclosporin on Vitreous Proliferation
Authors: Karakücük Sarper , Soyuer Serdar , Öner Ayse Öztürk , Soyuer Isın , Yaray Kadir , Mirza Ertugrul , Baskol Gülden , Akin Aynur
Published: December 2005

Double perforating ocular injuries were made in 30 rabbits and the effects of radiotherapy (RT) alone or in combination with cyclosporin (CS) on vitreous proliferation investigated. Thirteen rabbits in group 1 received RT alone (600 cGy), and 13 rabbits in group 2 received RT combined with 100 µg of intravitreal CS. No treatment was given to 4 rabbits in the control group (group 3). All animals were ophthalmologically examined on the 1st, 3rd, 7th, 14th and 28th days following the injury and the clinical findings scored; they were sacrificed on the 28th day, and histopathological scoring was made. The median histopathological score of the RT group (4.0; range: 0–8) was significantly higher than that of the CS + RT group (1.0; range: 0–5; p = 0.018). We conclude that intravitreal CS may be used as an adjunctive agent to RT to inhibit intraocular proliferation following penetrating ocular injury in rabbits.
Clinical Analysis of Benign Eyelid and Conjunctival Tumors
Authors: Baek Se Hyun , Chi Mi Jung
Published: December 2005

Purpose: To assess the relative frequency and clinicopathologic characteristics of benign conjunctival tumors. Methods: A retrospective study of 80 consecutive patients admitted to our hospital with benign eyelid and conjunctival tumor between April 2000 and November 2002 was undertaken, and clinical records including age, sex and involved site of tumors and pathology slides of the patients were reviewed retrospectively. Results: Twenty-three males and 33 females presented with benign eyelid tumors and 12 males and 12 females with conjunctival tumors. Mean age was 42.3 and 29.7 years, respectively. The lower eyelid was involved in 27 (48.2%) of eyelid tumors and the medial conjunctiva in 14 (58.3%) of conjunctival tumors. The most frequent tumor was intradermal nevus (44.6%), seborrheic keratosis (16.1%) and compound nevus (10.7%) in eyelid tumors, and compound nevus (29.2%) and intradermal nevus (25.0%) in conjunctival tumors. Conclusion: This report will provides a basic analysis of benign eyelid and conjunctival tumors.
Ménière’s Disease Is Associated with Single Nucleotide Polymorphisms in the Human Potassium Channel Genes, KCNE1 and KCNE3
Authors: Doi Katsumi , Sato Takashi , Kuramasu Toshihiro , Hibino Hiroshi , Kitahara Tadashi , Horii Arata , Matsushiro Naoki , Fuse Yuka , Kubo Takeshi
Published: December 2005

Although the bases for both the sporadic and inherited forms of Ménière’s disease (MD) remain undefined, it is likely to be multifactorial, one of the factors being a genetic predisposition. Recently, genetic association studies on complex diseases have become very popular and most of them are case-control studies using single nucleotide polymorphisms (SNPs) as markers. Mutations/polymorphisms in KCNE potassium channel genes might play a causative role in MD, because KCNE potassium channels have been suggested to be present and active in transmembrane ion and water transports in the inner ear. In the present study, to identify MD susceptibility genes, we have conducted a genetic association study with optimized sampling, optimized phenotyping/genotyping, and a selection of KCNE genes as the candidate genes. The SNPs analyses identified 112G/A SNP in the KCNE1 gene and 198T/C SNP in the KCNE3 gene in 63 definite MD cases as well as 205 and 237 non-MD control subjects. For both KCNE1 and KCNE3 genes, a significant difference in frequency of each SNP was confirmed between MD cases and non-MD control subjects. The result indicates that 112G/A SNP in the KCNE1 gene and 198T/C SNP in the KCNE3 gene could determine an increased susceptibility to develop MD.
Fas Ligand Expression and Its Correlation with Apoptosis and Proliferation in Lobund-Wistar Prostate Carcinomas
Authors: Gutierrez Linda S. , Noria Francisco , Finol Hector , Sun Longhua , Castellino Francis , Pollard Morris
Published: December 2005

Objective: The Fas (CD95) interaction with its receptor Fas ligand (FasL) is one of the main mechanisms of cell apoptosis. High expression of FasL has been consistently observed in a variety of human cancers. In this study, we evaluated FasL and its relationship with apoptosis and proliferation in Lobund-Wistar (L-W) cancers. The L-W rat strain develops spontaneous and induced adenocarcinomas in the anterior prostate and seminal vesicles. Although FasL expression has been observed in a subset of human prostate carcinomas, this multistage model allowed in vivo evaluation of subclones of malignant cells with a single genetic susceptibility. Methods: Apoptosis was evaluated in spontaneous, induced and transplanted tumors as well as metastasis using the terminal deoxynucleotidyl transferase-mediated dUTP nick end-labeling (TUNEL) technique and transmission electron microscopy. Proliferating cell nuclear antigen (PCNA) and FasL expression were detected using immunohistochemistry and analyzed according to the number of positive cells and intensity of staining using a semiquantitive method. Results: Apoptotic indexes were significantly higher in spontaneous tumors compared to induced (p < 0.008), transplanted tumors (p < 0.0112) and metastases (p < 0.009). TUNEL-positive cells were frequently observed in the leukocytic infiltrate of the stroma in transplanted carcinomas and metastases. These findings were confirmed by electron microscopy. FasL expression was not uniformly localized in L-W carcinomas and its highest expression was observed in transplanted tumors and metastasis (p < 0.005). Moreover, PCNA indices were directly correlated with cancers showing high FasL total scores (Hscores). Conclusions: In this model, high FasL expression was associated with cells displaying low apoptotic indexes and high PCNA index. Therefore, analysis of FasL may have clinical relevance in detecting the malignant potential of prostate cancers.
Twiddler’s Syndrome: An Interesting Cause of Pacemaker Failure
Authors: Castillo Ricardo , Cavusoglu Erdal
Published: December 2005

This case report describes a patient with twiddler’s syndrome, a rare condition of permanent pacemaker failure resulting from inadvertent or deliberate rotation of the pulse generator causing lead dislodgement. This report underscores the importance of dementia as a risk factor for twiddler’s syndrome.
Orange Germin-Like Glycoprotein Cit s 1: An Equivocal Allergen
Authors: Ahrazem Oussama , Ibáñez M. Dolores , López-Torrejón Gema , Sánchez-Monge Rosa , Sastre Joaquin , Lombardero Manuel , Barber Domingo , Salcedo Gabriel
Published: December 2005

Background: Orange allergens are virtually unknown, in spite of the large consumption of this fruit. Germin-like proteins, together with vicilins and legumins, form the cupin superfamily of plant proteins, which includes many seed allergens. Methods: Twenty-nine patients with allergy to oranges were studied. A major IgE-binding protein from orange extracts was isolated by means of a two-step cation-exchange chromatographic protocol. The allergen was characterized by N-terminal amino acid sequencing and MALDI analysis, and its reactivity explored by specific IgE determination in individual sera, ELISA inhibition assays and in vivo skin prick tests (SPT). Chemical deglycosylation of the purified allergen was achieved by trifluoromethylsulfonate acid treatment. Results: The 24-kDa purified allergen, designated Cit s 1, was identified as a germin-like glycoprotein, based on its N-terminal amino acid sequence, molecular size and recognition by rabbit anti-complex N-linked glycan antibodies. Specific IgE to Cit s 1 was detected in 62% of 29 individual sera from orange-allergic patients, whereas positive SPT responses to the purified allergen were obtained in only 10% of such patients. Deglycosylation of Cit s 1 resulted in a loss of its IgE-binding capacity. Moreover, the unrelated plant glycoprotein horseradish peroxidase inhibited over 70% the IgE-binding to Cit s 1. Conclusions: Over 60% of patients with allergy to oranges show specific IgE to Cit s 1. However, the purified allergen exerts a low in vivo reactivity. Complex N-linked glycans seem to play a prominent role in the IgE-binding capacity of Cit s 1. This characteristic of Cit s 1, as well as of other orange glycoproteins, could lead to false positives if the diagnosis of allergy to oranges is mainly based on in vitro specific IgE determination.
Expression of Vascular Adhesion Protein-1 in Atopic Eczema
Authors: Madej Aneta , Reich Adam , Orda Alina , Szepietowski Jacek C.
Published: December 2005

Background:Vascular adhesion protein-1 (VAP-1) is an adhesion molecule with an enzymatic activity which partakes in the migration process of lymphocytes. The aim of this study was to investigate VAP-1 expression in atopic eczema (AE) in comparison with healthy controls and psoriatic individuals. Material and Methods:Forty adult patients suffering from AE aged between 18 and 56 years were included in the study. The control group consisted of 35 healthy volunteers aged between 19 and 49 years and of 71 psoriatic patients aged between 23 and 89 years. The serum concentration of soluble VAP-1 (sVAP-1) was evaluated by ELISA and VAP-1 expression in the skin by immunohistochemistry. Results: Serum level of sVAP-1 in AE patients before treatment was significantly higher compared with healthy volunteers. Similarly, a higher mean number of VAP-1-positive vessels was found in both lesional and nonlesional atopic skin compared with healthy skin. Treatment of AE resulted in a significant reduction in the serum level of sVAP-1. On the other hand, both the serum level of sVAP-1 and the number of dermal vessels with expression of VAP-1 were significantly lower in AE patients compared with psoriatic individuals. Conclusion: This study indicates the important role of VAP-1 in the pathogenesis of chronic inflammatory cutaneous disorders, including AE.
Stereospecific and Redox-Sensitive Increase in Monocyte Adhesion to Endothelial Cells by Homocysteine
Authors: Postea Otilia , Krotz Florian , Henger Anna , Keller Christiane , Weiss Norbert
Published: December 2005

Objective—

Previous studies have shown that elevated homocysteine (Hcy) levels promote the development of atherosclerotic lesions in atherosclerosis-prone animal models. There is evidence that oxidant stress contributes to Hcy’s deleterious effects on the vasculature. The accumulation and adhesion of monocytes to the vascular endothelium is a critical event in the development of atherosclerosis. We investigated the effects of Hcy on the interaction between human endothelial cells (EC) (EC line EA.hy 926 and primary human umbilical vein EC [HUVEC]) and the monocytic cell line THP-1, and the impact of vascular oxidant stress and redox-sensitive signaling pathways on these events.

Methods and Results—

L-Hcy, but not D-Hcy, increases the production of reactive oxygen species inside EC, enhances nuclear factor(NF)-κB activation, and stimulates intercellular adhesion molecule-1 (ICAM-1) RNA transcription and cell surface expression. This leads to a time- and dose-dependent increase in monocyte adhesion to ECs. Pretreatment of ECs with superoxide scavengers (MnTBAP and Tiron) or with an inhibitor of NF-κB activation abolished Hcy-induced monocyte adhesion, ICAM-1 expression, and nuclear translocation of NF-κB.

Conclusions—

These findings suggest that reactive oxygen species produced under hyperhomocysteinemic conditions may induce a proinflammatory situation in the vessel wall that initiates and promotes atherosclerotic lesion development.
OxLDL–IgG Immune Complexes Induce Survival of Human Monocytes
Authors: Oksjoki Riina , Kovanen Petri T. , Lindstedt Ken A. , Jansson Bo , Pentikäinen Markku O.
Published: December 2005

Objective—

Immune complexes containing oxidatively modified low-density lipoprotein (oxLDL) particles are deposited in human atherosclerotic lesions during atherogenesis. Here we studied whether OxLDL–IgG immune complexes (OxLDL–IgG ICs) affect survival of human monocytes.

Methods and Results—

As demonstrated by light microscopy, and analysis of cell proliferation, caspase-3 activity, and DNA fragmentation, OxLDL–IgG ICs promoted survival of cultured human monocytes by decreasing their spontaneous apoptosis. OxLDL–IgG ICs induced a concentration-dependent production of the major monocyte growth factor, monocyte colony-stimulating factor (M-CSF), by the monocytes, but its inhibition was without effect on OxLDL–IgG IC–induced monocyte survival. Rather, OxLDL–IgG ICs induced rapid phosphorylation of Akt, suggesting a direct anti-apoptotic effect mediated by cross-linking of Fcγ receptors. Experiments with receptor blocking antibodies revealed that the OxLDL–IgG IC–induced monocyte survival was mediated by Fcγ receptor I.

Conclusions—

The results show that OxLDL–IgG ICs promote survival of monocytes by cross-linking Fcγ receptor I and activating Akt-dependent survival signaling. The results reveal a novel mechanism by which an immune reaction toward oxLDL can play a role in the accumulation of macrophages in human atherosclerotic lesions.
Identification of the cAMP-Responsive Enhancer of the Murine ABCA1 Gene
Authors: Le Goff Wilfried , Zheng Ping , Brubaker Gregory , Smith Jonathan D.
Published: December 2005

Objective—

To determine the mechanism by which expression of the murine ABCA1 gene is highly induced by cAMP analogues.

Methods and Results—

ABCA1 mRNA turnover cannot account for its induction by cAMP. Thus cAMP induction of ABCA1 mRNA occurs at a transcriptional level. Shotgun cloning DNA fragments from the murine ABCA1 locus identified a strong cAMP responsive enhancer located in the first intron, which led to 25- to 100-fold cAMP-mediated induction of reporter gene activity. Deletions and mutations of this enhancer led to the identification a cAMP-responsive element (CRE) that was essential for the cAMP induction. Furthermore, the capacity of this CRE site to mediate the cAMP induction required the presence of a STAT3/4 element located 81 bp away. A dominant-negative CREB expression vector inhibited the cAMP induction of ABCA1, demonstrating that CREB was required for cAMP induction of ABCA1 expression in RAW264.7 cells.

Conclusion—

Phospho-CREB1 controls the cAMP-mediated induction of murine ABCA1 gene expression through a CRE site acting in cooperation with a nearby STAT element. This CRE site is not conserved in the human ABCA1 gene, explaining why human ABCA1 is not strongly stimulated by cAMP analogs.
Uremia-Specific Effects in the Arterial Media During Development of Uremic Atherosclerosis in Apolipoprotein E–Deficient Mice
Authors: Bro Susanne , Borup Rehannah , Andersen Claus B. , Moeller Flemming , Olgaard Klaus , Nielsen Lars B.
Published: December 2005

Objective—

Uremia accelerates formation of atherosclerosis-like lesions in apolipoprotein E–deficient (apoE
−/−
) mice. In this study, we compared gene expression patterns in classical and uremic atherosclerosis.

Methods and Results—

High-density oligonucleotide microarray analyses were performed with aortic RNA from 5/6 nephrectomized (NX) and sham-operated mice. After 12 weeks, NX apoE
−/−
mice had more atherosclerosis and 24 genes were differentially expressed as compared with
sham
apoE
−/−
mice. Nine genes expressed in muscle cells displayed reduced expression (3.3- to 142-fold,
P
<0.05), whereas osteopontin gene expression was increased 8.7-fold (
P
<0.05) in NX mice. Studies of NX wild-type mice suggested that the changes in NX apoE
−/−
mice were dependent on hypercholesterolemia. Nevertheless, lesioned versus nonlesioned areas of aortas from nonuremic apoE
−/−
mice with classical atherosclerosis displayed less pronounced reductions in expression of the muscle cell related genes than seen in NX apoE
−/−
mice even though the osteopontin gene expression was increased &15-fold. Electron microscopy showed more vacuolized and necrotic smooth muscle cells within the media underneath both nonlesioned and lesioned intima in NX than in
sham
apoE
−/−
mice.

Conclusion—

The results suggest that uremic vasculopathy in apoE
−/−
mice, in addition to intimal atherosclerosis, is characterized by a uremia-specific medial smooth muscle cell degeneration, which appears to be accentuated by hypercholesterolemia.
Effect of Inhibiting Cholesteryl Ester Transfer Protein on the Kinetics of High-Density Lipoprotein Cholesteryl Ester Transport in Plasma
Authors: Kee P. , Caiazza D. , Rye K.-A. , Barrett P.H.R. , Morehouse L.A. , Barter P.J.
Published: December 2005

Objective—

Inhibitors of cholesteryl ester transfer protein (CETP) have been developed as potential anti-atherogenic agents. Theoretically, however, they may be pro-atherogenic by blocking one of the pathways for removing high-density lipoprotein (HDL) cholesteryl esters (CE) from plasma in the final step of reverse cholesterol transport. Here we describe how CETP inhibition in rabbits impacts on the kinetics of HDL CE transport in plasma.

Methods and Results—

Administration of a CETP inhibitor reduced CETP activity by 80% to 90% and doubled the HDL cholesteryl ester concentration. Multi-compartmental analysis was used to determine HDL CE kinetics in CETP-inhibited and control rabbits after injection of tracer amounts of both native and reconstituted HDL labeled with
3
H in the CE moiety. In control rabbits, HDL CE was removed from plasma by both a direct pathway and an indirect pathway after transfer of HDL CE to the very-low-density lipoprotein/low-density lipoprotein fraction. In CETP-inhibited rabbits there was an almost complete block in removal via the indirect pathway. This did not compromise the overall removal of HDL CE from plasma, which was not different in control and inhibited animals.

Conclusion—

Inhibiting CETP in rabbits does not compromise the removal of HDL CE from plasma.
Transforming Growth Factor Beta 1 Induces Neointima Formation Through Plasminogen Activator Inhibitor-1–Dependent Pathways
Authors: Otsuka Goro , Agah Ramtin , Frutkin Andrew D. , Wight Thomas N. , Dichek David A.
Published: December 2005

Objective—

The mechanisms through which transforming growth factor (TGF)-β1 promotes intimal growth, and the pathways through which TGF-β1 expression is regulated in the artery wall, are incompletely understood. We used a mouse model to investigate mechanisms of TGF-β1–induced intimal growth.

Methods and Results—

Adenovirus-mediated overexpression of TGF-β1 in uninjured carotid arteries of wild-type mice induced formation of a cellular and matrix-rich intima. Intimal growth appeared primarily due to cell migration and matrix accumulation, with only a negligible contribution from cell proliferation. Overexpression of TGF-β1 also stimulated expression of plasminogen activator inhibitor type 1 (plasminogen activator inhibitor [PAI]-1) in the artery wall. To test the hypothesis that PAI-1 is a critical downstream mediator of TGF-β1–induced intimal growth, we transduced carotid arteries of PAI-1–deficient (
Serpine1
−/−
) mice with the TGF-β1–expressing vector. Overexpression of TGF-β1 in
Serpine1
−/−
arteries did not increase intimal growth, matrix accumulation, cell migration, or proliferation. Moreover, TGF-β1–transduced arteries of
Serpine1
−/−
mice secreted 6- to 10-fold more TGF-β1 than did arteries of wild-type mice that were infused with the same concentration of the TGF-β1–expressing vector.

Conclusions—

PAI-1 is both a critical mediator of TGF-β1–induced intimal growth and a key negative regulator of TGF-β1 expression in the artery wall.
Apolipoprotein E Recycling
Authors: Heeren Joerg , Beisiegel Ulrike , Grewal Thomas
Published: December 2005

After receptor-mediated endocytosis, the intracellular fate of triglyceride-rich lipoproteins (TRLs) is far more complex than the classical degradation pathway of low-density lipoproteins. Once internalized, TRLs disintegrate in peripheral endosomes, followed by a differential sorting of TRL components. Although core lipids and apolipoprotein B are targeted to lysosomes, the majority of TRL-derived apolipoprotein E (apoE) remains in peripheral recycling endosomes. This pool of TRL-derived apoE is then mobilized by high-density lipoproteins (HDLs) or HDL-derived apoA-I to be recycled back to the plasma membrane, followed by apoE resecretion and the subsequent formation of apoE-containing HDL. The HDL-induced recycling of apoE is accompanied by cholesterol efflux and involves the internalization and targeting of HDL-derived apoA-I to endosomes containing both apoE and cholesterol. These findings point to a yet unknown intracellular link between TRL-derived apoE, cellular cholesterol transport, and HDL metabolism. Recent studies provide first evidence that impaired recycling of TRL-derived apoE4, but not apoE3, is associated with intracellular cholesterol accumulation, which might explain some well-documented effects of apoE4 on HDL metabolism. This review summarizes the current understanding of apoE recycling and its potential role in the regulation of plasma apoE levels in the postprandial state.
Increased Sarcoplasmic Reticulum Calcium Leak but Unaltered Contractility by Acute CaMKII Overexpression in Isolated Rabbit Cardiac Myocytes
Authors: Kohlhaas Michael , Zhang Tong , Seidler Tim , Zibrova Darya , Dybkova Nataliya , Steen Astrid , Wagner Stefan , Chen Lu , Heller Brown Joan , Bers Donald M. , Maier Lars S.
Published: December 2005

The predominant cardiac Ca
2+
/calmodulin-dependent protein kinase (CaMK) is CaMKIIδ. Here we acutely overexpress CaMKIIδ
C
using adenovirus-mediated gene transfer in adult rabbit ventricular myocytes. This circumvents confounding adaptive effects in CaMKIIδ
C
transgenic mice. CaMKIIδ
C
protein expression and activation state (autophosphorylation) were increased 5- to 6-fold. Basal twitch contraction amplitude and kinetics (1 Hz) were not changed in CaMKIIδ
C
versus LacZ expressing myocytes. However, the contraction–frequency relationship was more negative, frequency-dependent acceleration of relaxation was enhanced (τ
0.5Hz
/τ
3Hz
=2.14±0.10 versus 1.87±0.10), and peak Ca
2+
current (
I
Ca
) was increased by 31% (−7.1±0.5 versus −5.4±0.5 pA/pF,
P
<0.05). Ca
2+
transient amplitude was not significantly reduced (−27%,
P
=0.22), despite dramatically reduced sarcoplasmic reticulum (SR) Ca
2+
content (41%;
P
<0.05). Thus fractional SR Ca
2+
release was increased by 60% (
P
<0.05). Diastolic SR Ca
2+
leak assessed by Ca
2+
spark frequency (normalized to SR Ca
2+
load) was increased by 88% in CaMKIIδ
C
versus LacZ myocytes (
P
<0.05; in an multiplicity-of-infection–dependent manner), an effect blocked by CaMKII inhibitors KN-93 and autocamtide-2–related inhibitory peptide. This enhanced SR Ca
2+
leak may explain reduced SR Ca
2+
content, despite measured levels of SR Ca
2+
-ATPase and Na
+
/Ca
2+
exchange expression and function being unaltered. Ryanodine receptor (RyR) phosphorylation in CaMKIIδ
C
myocytes was increased at both Ser2809 and Ser2815, but FKBP12.6 coimmunoprecipitation with RyR was unaltered. This shows for the first time that acute CaMKIIδ
C
overexpression alters RyR function, leading to enhanced SR Ca
2+
leak and reduced SR Ca
2+
content but without reducing twitch contraction and Ca
2+
transients. We conclude that this is attributable to concomitant enhancement of fractional SR Ca
2+
release in CaMKIIδ
C
myocytes (ie, CaMKII-dependent enhancement of RyR Ca
2+
sensitivity during diastole and systole) and increased
I
Ca
.
Impaired Angiogenesis in Glutathione Peroxidase-1–Deficient Mice Is Associated With Endothelial Progenitor Cell Dysfunction
Authors: Galasso Gennaro , Schiekofer Stephan , Sato Kaori , Shibata Rei , Handy Diane E. , Ouchi Noriyuki , Leopold Jane A. , Loscalzo Joseph , Walsh Kenneth
Published: December 2005

Several vascular disease are characterized by elevated levels of reactive oxygen species (ROS). Vascular endothelium is protected from oxidant stress by expressing enzymes such as glutathione peroxidase type 1 (GPx-1). In this study, we investigated the effect of vascular oxidant stress on ischemia-induced neovascularization in a murine model of homozygous deficiency of GPx-1. GPx-1–deficient mice showed impaired revascularization following hindlimb ischemic surgery based on laser Doppler measurements of blood flow and capillary density in adductor muscle. GPx-1–deficient mice also showed an impaired ability to increase endothelial progenitor cell (EPC) levels in response to ischemic injury or subcutaneous administration of vascular endothelial growth factor protein. EPCs isolated from GPx-1–deficient mice showed a reduced ability to neutralize oxidative stress in vitro, which was associated with impaired migration toward vascular endothelial growth factor and increased sensitivity to ROS-induced apoptosis. EPCs isolated from GPx-1–deficient mice were impaired in their ability to promote angiogenesis in wild-type mice, whereas wild-type EPCs were effective in stimulating angiogenesis in GPx-1–deficient mice. These data suggest that EPC dysfunction is a mechanism by which elevated levels of ROS can contribute to vascular disease.
H11 Kinase Prevents Myocardial Infarction by Preemptive Preconditioning of the Heart
Authors: Depre Christophe , Wang Li , Sui Xiangzhen , Qiu Hongyu , Hong Chull , Hedhli Nadia , Ginion Audrey , Shah Amy , Pelat Michel , Bertrand Luc , Wagner Thomas , Gaussin Vinciane , Vatner Stephen F.
Published: December 2005

Ischemic preconditioning confers powerful protection against myocardial infarction through pre-emptive activation of survival signaling pathways, but it remains difficult to apply to patients with ischemic heart disease, and its effects are transient. Promoting a sustained activation of preconditioning mechanisms in vivo would represent a novel approach of cardioprotection. We tested the role of the protein H11 kinase (H11K), which accumulates by 4- to 6-fold in myocardium of patients with chronic ischemic heart disease and in experimental models of ischemia. This increased expression was quantitatively reproduced in cardiac myocytes using a transgenic (TG) mouse model. After 45 minutes of coronary artery occlusion and reperfusion, hearts from TG mice showed an 82±5% reduction in infarct size compared with wild-type (WT), which was similar to the 84±4% reduction of infarct size observed in WT after a protocol of ischemic preconditioning. Hearts from TG mice showed significant activation of survival kinases participating in preconditioning, including Akt and the 5′AMP-activated protein kinase (AMPK). H11K directly binds to both Akt and AMPK and promotes their nuclear translocation and their association in a multiprotein complex, which results in a stimulation of survival mechanisms in cytosol and nucleus, including inhibition of proapoptotic effectors (glycogen synthase kinase-3β, Bad, and Foxo), activation of antiapoptotic effectors (protein kinase Cε, endothelial and inducible NO synthase isoforms, and heat shock protein 70), increased expression of the hypoxia-inducible factor-1α, and genomic switch to glucose utilization. Therefore, activation of survival pathways by H11K preemptively triggers the antiapoptotic and metabolic response to ischemia and is sufficient to confer cardioprotection in vivo equally potent to preconditioning.
Adherent Platelets Recruit and Induce Differentiation of Murine Embryonic Endothelial Progenitor Cells to Mature Endothelial Cells In Vitro
Authors: Langer Harald , May Andreas Eberhard , Daub Karin , Heinzmann Ulrich , Lang Peter , Schumm Michael , Vestweber Dietmar , Massberg Steffen , Schönberger Tanja , Pfisterer Iris , Hatzopoulos Antonis K. , Gawaz Meinrad
Published: December 2005

The homing and differentiation mechanisms of endothelial progenitor cells (EPCs) at sites of vascular lesions are unclear. To investigate whether platelets play a role in the recruitment and differentiation of EPCs, we made use of a robust mouse embryonic EPC (eEPC) line that reliably differentiates to a mature endothelial phenotype. We found that platelets stimulate chemotaxis and migration of these murine eEPCs. Further, the substantial adhesion of murine eEPCs on immobilized platelets that occurs under dynamic flow conditions is inhibited by neutralizing anti–P-selectin glycoprotein ligand-1 and anti–VLA-4 (β
1
-integrin) monoclonal antibodies but not by anti-CD11b (a
M
-integrin; macrophage antigen-1). Coincubation of murine eEPCs with platelets for 5 days induced differentiation of EPCs to mature endothelial cells as verified by positive von Willebrand factor immunofluorescence and detection of Weibel Palade bodies through electron microscopy. We conclude that platelets may play a critical part in the capture and subsequent differentiation of murine eEPCs at sites of vascular lesions, revealing a possible new role of platelets in neoendothelization after vascular injury.
Comparison of ABC/2 Estimation Technique to Computer-Assisted Planimetric Analysis in Warfarin-Related Intracerebral Parenchymal Hemorrhage
Authors: Huttner Hagen B. , Steiner Thorsten , Hartmann Marius , Köhrmann Martin , Juettler Eric , Mueller Stephan , Wikner Johannes , Meyding-Lamade Uta , Schramm Peter , Schwab Stefan , Schellinger Peter D.
Published: December 2005

Background and Purpose—

The ABC/2 formula is a reliable estimation technique of intracerebral hematoma volume. However, oral anticoagulant therapy (OAT)–related intracerebral hemorrhage (ICH) compared with primary ICH is based on a different pathophysiological mechanism, and various shapes of hematomas are more likely to occur. Our objective was to validate the ABC/2 technique based on analyses of the hematoma shapes in OAT-related ICH.

Methods—

We reviewed the computed tomography scans of 83 patients with OAT-associated intraparenchymal ICH. Location was divided into deep, lobar, cerebellar, and brain stem hemorrhage. Shape of the ICH was divided into (A) round-to-ellipsoid, (B) irregular with frayed margins, and (C) multinodular to separated. The ABC/2 technique was compared with computer-assisted planimetric analyses with regard to hematoma site and shape.

Results—

The mean hematoma volume was 40.83±3.9 cm
3
(ABC/2) versus 36.6±3.5 cm
3
(planimetric analysis). Bland–Altman plots suggested equivalence of both estimation techniques, especially for smaller ICH volumes. The most frequent location was a deep hemorrhage (54%), followed by lobar (21%), cerebellar (14%) and brain stem hemorrhage (11%). The most common shape was round-to-ellipsoid (44%), followed by irregular ICH (31%) and separated and multinodular shapes (25%). In the latter, ABC/2 formula significantly overestimated volume by +32.1% (round shapes by +6.7%; irregular shapes by +14.9%;
P
ANOVA <0.01). Variation of the denominator toward ABC/3 in cases of irregularly and separately shaped hematomas revealed more a precise volume estimation with a deviation of −10.3% in irregular and +5.6% in separately shaped hematomas.

Conclusions—

In patients with OAT-related ICH, >50% of bleedings are irregularly shaped. In these cases, hematoma volume is significantly overestimated by the ABC/2 formula. Modification of the denominator to 3 (ie, ABC/3) measured ICH volume more accurately in these patients potentially facilitating treatment decisions.
Altered Hemodynamics and Regional Cerebral Blood Flow in Patients With Hemodynamically Significant Stenoses
Authors: Roc Anne C. , Wang Jiongjiong , Ances Beau M. , Liebeskind David S. , Kasner Scott E. , Detre John A.
Published: December 2005

Background and Purpose—

Blood oxygen level–dependent (BOLD) contrast largely depends on changes in cerebral blood flow (CBF). Because cerebrovascular disease may result in altered CBF, we assessed the temporal dynamics and magnitude of the BOLD response in patients with major arterial stenoses.

Methods—

Seven patients with hemodynamically significant stenoses affecting the anterior circulation (primarily left internal carotid and middle cerebral arteries) were compared with 7 neurologically healthy subjects. Continuous arterial spin-labeled perfusion MRI was used to measure resting CBF globally and within various vascular distributions. The BOLD response was acquired during a visually guided bilateral handball squeeze task while motor performance was recorded by a pressure transducer.

Results—

Baseline CBF was reduced in bilateral middle cerebral artery and left anterior cerebral artery territories in patients. A prolonged BOLD hemodynamic response was observed in patients in bilateral primary motor cortices but not visual cortex. Patients also exhibited a larger early negative BOLD response, or “initial dip,” in left primary motor cortex. There were no differences in motor performance between groups, suggesting behavioral differences were not primarily responsible for the characteristics of the BOLD response.

Conclusions—

An initial deoxygenation followed by a delayed hyperemic BOLD response was observed in patients, although resting flow values were not within an ischemic range. A simple visuomotor BOLD activation paradigm can reflect alterations in the hemodynamic response in patients with hemodynamically significant stenoses.
Endovascular Recanalization Therapy in Acute Ischemic Stroke
Authors: Choi Jae H. , Bateman Brian T. , Mangla Sundeep , Marshall Randolph S. , Prabhakaran Shyam , Chong Ji , Mohr Jay P. , Mast Henning , Pile-Spellman John
Published: December 2005

Background and Purpose—

To assess the outcome in acute ischemic stroke patients not eligible for systemic thrombolysis (outside the 3-hour time window, after surgery, or on anticoagulant) undergoing endovascular recanalization therapy (ERT) at the Columbia University Medical Center (CUMC) and to determine US nationwide usage and outcome of ERT in acute ischemic stroke.

Methods—

Patients treated at CUMC from 2001 to 2004 and the Nationwide Inpatient Sample (NIS) comprising 20% of all admissions in the United States from 1999 to 2002 were analyzed retrospectively.

Results—

Thirty-one patients underwent ERT. Mean age was 68±14 years, 68% were female, and 45% nonwhite (occlusion sites: internal carotid artery 29%; middle cerebral artery 39%; posterior circulation 32%). Pharmacological or mechanical ERT was initiated beyond 3 hours after symptom onset (median time 4.4 hours) in 61%, 29% had surgery, and 39% were on anticoagulant medication. At discharge, 32% had modified Rankin Scale scores of 0 to 2 (52% discharged home or to rehabilitation facilities); overall mortality was 29%, of which 19% were fatal intracerebral hemorrhages. From the NIS cohort, 477 patients (0.17% of all strokes and 14% of all thrombolysis cases) underwent ERT. Fifteen percent died, and ≈50% were discharged home or to rehabilitation facilities. Intracerebral hemorrhage occurred in 6%. Fewer good outcomes of the CUMC cohort may be explained by more unfavorable premorbid patient characteristics compared with the NIS cohort.

Conclusion—

Despite significant variability in patient characteristics and treatment methods among 2 sources of data analyzed, ERT in stroke patients not eligible for intravenous thrombolysis appears to be a relatively safe and effective treatment alternative that is being used increasingly nationwide.
Distribution of Carotid Arterial Lesions in Chinese Patients With Transient Monocular Blindness
Authors: Hsu Hung-Yi , Yang Fu-Yi , Chao A-Ching , Chen Yen-Yu , Chung Chih-Ping , Sheng Wen-Yung , Hu Han-Hwa
Published: December 2005

Background and Purpose—

Asian patients with cerebrovascular diseases have more intracranial atherosclerosis and less extracranial carotid artery stenosis compared with white patients. We systemically evaluated the distribution of carotid arterial lesions in Chinese patients with transient monocular blindness (TMB), which was rarely reported.

Methods—

We prospectively evaluated 105 consecutive patients with TMB. All of the patients received ocular and physical examinations, blood tests for coagulation function and autoimmune diseases, and ultrasonography of cervical and intracranial arteries. All of the carotid lesions were confirmed by magnetic resonance angiography or cerebral angiography.

Results—

Of the 36 (34.3%) patients with significant carotid stenosis (≥50%), 16 (15.2%) had extracranial carotid stenosis; 17 (16.2%) had carotid siphon stenosis; and 3 (2.9%) had both. The duration, onset, and patterns of visual loss were not different between patients with and without carotid arterial lesion.

Conclusions—

This study signified the importance of carotid siphon stenosis as a probable underlying etiology for TMB in Chinese patients.
Accuracy of Color Duplex Ultrasound Diagnosis of Spontaneous Carotid Dissection Causing Ischemia
Authors: Benninger David H. , Georgiadis Dimitri , Gandjour Joubin , Baumgartner Ralf W.
Published: December 2005

Background and Purpose—

Spontaneous dissection of the cervical internal carotid artery (sICAD) is mainly assessed with MRI and magnetic resonance angiography (MRA), which are not always at hand. In contrast, color duplex sonography (CDS) is readily available. We undertook this prospective study to examine the accuracy of CDS to diagnose sICAD in patients with first carotid territory ischemia.

Methods—

Consecutive patients with first carotid territory stroke or transient ischemic attack or retinal ischemia underwent clinical and laboratory examinations, ECG, CDS of the cerebral arteries, cranial computed tomography in case of stroke or transient ischemic attack, and echocardiography and 24-hour ECG in selected cases. Patients were included, if they were <65 years of age, CDS showed a probable sICAD (cervical internal carotid artery stenosed or occluded), or had no determined etiology of ischemia. All of the included patients underwent cervical MRI and MRA±cerebral catheter angiography. The sonographer was blinded to the results of MRI and angiography studies.

Results—

We included 177 of 1652 screened patients. Excluded patients (n=1475) were ≥65 years old (n=818), had another determined cause of ischemia (n=1475), and had intracranial hemorrhage (n=58). CDS diagnosed sICAD in 77 of 177 patients, and the etiology of ischemia was undetermined in the remaining 100 patients. Cervical MRI and angiography showed 74 sICAD; there were 6 falsely positive and 3 falsely negative CDS findings. Thus, sensitivity, specificity, and positive and negative predictive values for CDS diagnosis of patients with sICAD causing carotid territory ischemia was 96%, 94%, 92%, and 97%, respectively.

Conclusions—

Color duplex ultrasound allows the reliable exclusion of sICAD in patients with carotid territory ischemia, whereas diagnosis of CDS of sICAD must be confirmed with cervical MRI and MRA.
Markers of Inflammation and Infection Influence the Outcome of Patients With Baseline Asymptomatic Carotid Lesions
Authors: Corrado Egle , Rizzo Manfredi , Tantillo Rosalba , Muratori Ida , Bonura Francesca , Vitale Giustina , Novo Salvatore
Published: December 2005

Background and Purpose—

It is still in debate whether the evaluation of markers of infection and inflammation may be of importance for cerebrovascular and cardiovascular prevention, and we aimed to investigate this field in a prospective 5-year clinical follow-up study in patients with early stages of atherosclerosis.

Methods—

We studied 668 subjects divided in 3 groups according to the results of carotid ultrasound examination: (1) normal subjects, if intima-media thickness (IMT) was <0.9 mm; (2) with IMT, if IMT was between 0.9 and 1.5 mm; and (3) with asymptomatic carotid plaque, if IMT was >1.5 mm. Traditional cardiovascular risk factors were investigated, and laboratory analysis included measurement of plasma lipids, fibrinogen, C-reactive protein, IgG antibodies for
helicobacter pylori
(HP), cytotoxic HP, cytomegalovirus, and
chlamydia pneumoniae
.

Results—

Cerebrovascular or cardiovascular events were registered in 18% of patients during the follow-up, and at multivariate analysis we found that the high levels of fibrinogen (
P
<0.0001) and C-reactive protein (
P
=0.014), the seropositivity to cytotoxic HP (
P
=0.001) and
chlamydia pneumoniae
(
P
=0.026), the presence of IMT or asymptomatic carotid plaque (
P
<0.0001), and the total burden of infections (
P
<0.0001) were the variables predictive of the clinical events.

Conclusions—

Beyond traditional cardiovascular risk factors, markers of inflammation and infections seem to significantly influence the occurrence of cerebrovascular and cardiovascular events in patients with baseline asymptomatic carotid lesions.