bluuebunny/crossref_metadata_2025 huggingface dataset:
USE OF MIXTURE DESIGN AND FLOW CHARACTERISTICS TO FORMULATE ICE CREAM COMPOUND COATINGS
Authors: GHORBEL DORRA , DOUIRI IMEN , ATTIA HAMADI , TRIGUI MOEZ
Published: July 2009

Flow properties of three industrial formulas of ice cream compound coatings were studied in the steady state regime with the coaxial geometry. Flow curves showed shear‐thinning thixotropic behavior. As for molten chocolate, the Casson–Steiner equation was used to fit the compound coating rheograms in the shear rate range 380–1,000 s
−1
. The effects of agitation rate and time applied during coating preparation were studied. A new formula of coating was realized using a mixture design and, as dependent variables, the apparent viscosities at different shear rates. Results showed that the flow properties of molten compound coatings could be reproduced by this statistical method, but subsequent research on the influence of fat content and nature, and on the rheological parameters controlling the solidification of coatings, should be carried out to improve their formulation.

PRACTICAL APPLICATIONS

Formulation of food materials using the scientific (and not the traditional) method is essential in predicting the quality of the final product and reducing the period and cost of developing. This method is based on the use of statistical experimental design and needs the understanding of the techno‐functional properties of the food materials (such as physicochemical properties and rheological behavior). The aim of this research was to use this scientific method in developing a new coating formula. This work illustrates the importance of the mixture design and the rheological properties of molten compound coatings in their formulation. In practice, we showed that the dependent variables used in the mixture design would be chosen with great attention, with respect to the fat contained in coatings. The fat nature and content has a great influence on the functional properties of the coatings used in ice cream manufacture, which is the subject of a forthcoming paper.
Behçet's disease – a delay in diagnosis: why look in the mouth?
Authors: Dalghous A.M. , Elkhabuli J.O. , Fortune F.
Published: July 2009

A rare case of severe Behçet's disease in a young patient is presented. The patient unnecessarily suffered from the devastating effects of the disease as a result of a delay in diagnosis, and consequently, initiation of the appropriate treatment. However, once a diagnosis was made, he was successfully treated with large doses of corticosteroids together with azathioprine, warfarin and aspirin. We highlight the importance of oral examination in diagnosing systemic diseases.
Swimming and asthma: factors underlying respiratory symptoms in competitive swimmers
Authors: Päivinen Marja Kristiina , Keskinen Kari Lasse , Tikkanen Heikki Olavi
Published: July 2009

Background:  Swimming is recommended for asthmatics. However, many competitive swimmers report asthmatic symptoms. While some studies identify the swimming environment as a trigger for allergy and asthmatic symptoms, even more studies suggest swimming to be suitable for people with allergies and asthma. The factors behind the symptoms were studied first by determining the prevalence of asthma, allergy and self‐reported asthmatic symptoms in experienced Finnish swimmers and then by examining the relationships between the reported symptoms and the main triggering factors: medical history, environment and exercise intensity.

Materials and Methods:  Top swimmers (n = 332) of the Finnish Swimming Association registry (N = 4578) were asked to complete a structured questionnaire on their medical history, swimming background, swimming environment and symptoms in different swimming intensities. Two hundred experienced swimmers, 107 females and 93 males, with an average age of 18.5 [standard deviation (SD) = 3.0] years and a swimming training history of 9 (SD = 3.8) years completed the questionnaire.

Results:  Physician‐diagnosed asthma was reported by 32 swimmers (16%), including 24 (12%) with exercise‐induced asthma. Physician‐diagnosed allergy was reported by 81 (41%) swimmers. Asthmatic symptoms during swimming were described by 84 subjects (42%). Most symptoms occurred when swimming exceeded speeds corresponding to the lactic/anaerobic threshold. Family history of asthma was significant and the most important risk factor for asthmatic symptoms.

Conclusions:  The prevalence of asthma in swimmers was higher than in the general population but not different from that in other endurance athletes. Family history of asthma and increased swimming intensity had the strongest associations with the reported asthmatic symptoms.

Please cite this paper as: Päivinen MK, Keskinen KL and Tikkanen HO. Swimming and asthma: factors underlying respiratory symptoms in competitive swimmers. The Clinical Respiratory Journal 2010; 4: 97–103.
Tissue‐direct PCR, a rapid and extraction‐free method for barcoding of ferns
Authors: LI F‐W. , KUO L‐Y. , HUANG Y‐M. , CHIOU W‐L. , WANG C‐N.
Published: July 2009

Fern gametophytes and young sporophytes often provide too little material for DNA extraction and are particularly difficult to identify to genus. Here we developed an efficient procedure called ‘Tissue‐direct PCR’, in which a slice of fern tissue is mixed with PCR reagents and primers, allowing certain genomic regions to be amplified directly in the thermal cycler. For these diminutive and featureless stages of ferns, Tissue‐direct PCR combined with amplifying plant barcodes promises to make the identification of immature ferns easy and rapid. Tissue‐direct PCR would also be very helpful for large‐scale ecological studies surveying distribution and population structure.
Experimental and Numerical Study of the LENS Rapid Fabrication Process
Authors: Wang Liang , Felicelli Sergio D. , Craig James E.
Published: July 2009

Several aspects of the thermal behavior of deposited stainless steel 410 (SS410) during the laser engineered net shaping (LENS™) process were investigated experimentally and numerically. Thermal images in the molten pool and surrounding area were recorded using a two-wavelength imaging pyrometer system, and analyzed using THERMAVIZ™ software to obtain the temperature distribution. The molten pool size, temperature gradient, and cooling rate were obtained from the recorded history of temperature profiles. The dynamic shape of the molten pool, including the pool size in both travel direction and depth direction was investigated, and the effect of different process parameters was illustrated. The thermal experiments were performed in a LENS™ 850 machine with a 3 kW IPG Photonics laser for different process parameters. A three-dimensional finite element model was developed to calculate the temperature distribution in the LENS™ process as a function of time and process parameters. The modeling results showed good agreement with the experimental data.
Defect-mediated adsorption of methanol and carbon dioxide on BaTiO3(001)
Authors: Garra J. , Vohs J. M. , Bonnell D. A.
Published: July 2009

The surface chemistry of single crystal barium titanate (BaTiO3) has been studied using temperature programmed desorption (TPD). TPD measurements were performed with several probe molecules, including methanol and carbon dioxide. The role of oxygen vacancies in the adsorption and reaction of these molecules was examined by annealing the crystal under oxidizing or reducing conditions prior to performing TPD. It is shown that the adsorption and reaction of methanol and carbon dioxide are enhanced on BaTiO3(001) by annealing the crystal under reducing conditions.
Structure and Mechanism of a Na
+
-Independent Amino Acid Transporter
Authors: Shaffer Paul L. , Goehring April , Shankaranarayanan Aruna , Gouaux Eric
Published: July 2009

APC Transporter Structure

Amino acid, polyamine, and organocation (APC) transporters that move a range of organic molecules across the cell membrane are important in many cellular processes.

Shaffer
et al.

(p.
1010
; published online 16 July) report the crystal structure of apoApcT, a proton-dependent APC transporter. The structure shows similarity to the sodium-coupled amino acid transporter LeuT and has an amino group from a lysine in an equivalent position to a sodium ion in LeuT. This suggests common principles between proton- and sodium-coupled transporters.
Some acid-catalysed reactions of indol-3-yl and indol-2-yl disubstituted methanols
Authors: Santoso Mardi , Kumar Naresh , Black David StClair
Published: July 2009

1-Substituted indol-3-yl and indol-2-yl disubstituted methanols do not undergo acid-catalysed trimerisation to yield indolocyclotriveratrylenes, unlike the related primary 1-substituted indol-3-yl- and -2-ylmethanols. The 1-substituted indol-3-ylmethanols 10 and 11 gave diindol-3-ylmethanes 12 and 13, respectively, on treatment with p-toluenesulfonic acid in dichloromethane. In contrast, the indol-2-ylmethanols 22 and 23 gave the reduced indolo[3,2-b]carbazoles 24 and 25, respectively, on treatment with boron trifluoride etherate in benzene. An X-ray crystal structure of compound 24 is described.
Sulfonium-ion glycosidase inhibitors isolated from Salacia species used in traditional medicine, and related compounds
Authors: Mohan Sankar , Pinto B. Mario
Published: July 2009

A novel class of naturally-occurring glycosidase inhibitors, having sulfonium sulfate structures, has been isolated as bioactive components from Indian plants, belonging to the Salacia genus in the family Celastraceae, and used in Ayurvedic medicine for the treatment of type-2 diabetes. Thus far, five such sulfonium salts, namely, salacinol, kotalanol, salaprinol, ponkoranol and de-O-sulfonated kotalanol, have been isolated from this plant species. These structurally unique zwitterionic glycosidase inhibitors have received much attention due to their therapeutic potential in the treatment of type-2 diabetes. We recently reported a review article which focused mainly on salacinol and related analogues. The present review presents an update on the remaining four compounds from this class of glycosidase inhibitors, with respect to their isolation, glucosidase inhibitory activities, and synthesis. In addition, progress towards the stereochemical structure elucidation of kotalanol, through synthesis of analogues, is described. Review with 42 references.
Pathological roles of bone marrow-derived stellate cells in a mouse model of alcohol-induced fatty liver
Authors: Fujimiya Tatsuya , Liu Jinyao , Kojima Hideto , Shirafuji Seiko , Kimura Hiroshi , Fujimiya Mineko
Published: July 2009

Chronic alcohol consumption activates hepatic stellate cells (HSCs) and causes fatty degeneration in the liver. However, the origin of HSCs and the mechanism of fatty changes of the liver have not been fully elucidated. Here, we examined the roles of bone marrow-derived cells (BMDCs) in a mouse model with chronic alcohol consumption. We performed bone marrow transplantation from transgenic mice expressing green fluorescence protein (GFP) to female wild-type and ROSA mice (B6.129S7-Gt 26Sor/J, transgenic mice expressing β-galactosidase, β-gal) and treated them with ethanol (EtOH) for 8 or 16 wk. GFP-expressing BMDCs increased in the liver with EtOH treatment in a time-dependent manner. In response to excess alcohol consumption, ≈68% of the BMDCs became activated HSCs in that they expressed α-smooth muscle actin. Meanwhile, ≈67% and ≈66% of these BMDCs expressed Tnf-α and transforming growth factor (Tgf)-β1, respectively, and the activities were further supported by the excessive mRNA expression of Tnf-α and Tgf-β1 in RT-PCR, respectively. Cell fusion occurs between BMDCs and nonparenchymal cells but scarcely occurs between BMDCs and hepatocytes, demonstrated by double staining of β-gal/GFP and further supported by the Y-chromosome staining. The EtOH withdrawal normalized most of the abnormalities produced by chronic alcohol consumption. These results indicate that excess alcohol consumption stimulates both the homing of HSCs from the bone marrow and their profibrogenic cytokine production in a mouse model of alcohol-induced fatty liver disease.
Caveolin-1 mediates endotoxin inhibition of endothelin-1-induced endothelial nitric oxide synthase activity in liver sinusoidal endothelial cells
Authors: Kwok Willson , Lee Sang Ho , Culberson Cathy , Korneszczuk Katarzyna , Clemens Mark G.
Published: July 2009

Endothelin-1 (ET-1) plays a key role in the regulation of endothelial nitric oxide synthase (eNOS) activation in liver sinusoidal endothelial cells (LSECs). In the presence of endotoxin, an increase in caveolin-1 (Cav-1) expression impairs ET-1/eNOS signaling; however, the molecular mechanism is unknown. The objective of this study was to investigate the molecular mechanism of Cav-1 in the regulation of LPS suppression of ET-1-mediated eNOS activation in LSECs by examining the effect of caveolae disruption using methyl-β-cyclodextrin (CD) and filipin. Treatment with 5 mM CD for 30 min increased eNOS activity (+255%, P < 0.05). A dose (0.25 μg/ml) of filipin for 30 min produced a similar effect (+111%, P < 0.05). CD induced the perinuclear localization of Cav-1 and eNOS and stimulated NO production in the same region. Readdition of 0.5 mM cholesterol to saturate CD reversed these effects. Both the combined treatment with CD and ET-1 (CD + ET-1) and with filipin and ET-1 stimulated eNOS activity; however, pretreatment with endotoxin (LPS) abrogated these effects. Following LPS pretreatment, CD + ET-1 failed to stimulate eNOS activity (+51%, P > 0.05), which contributed to the reduced levels of eNOS-Ser1177 phosphorylation and eNOS-Thr495 dephosphorylation, the LPS/CD-induced overexpression and translocation of Cav-1 in the perinuclear region, and the increased perinuclear colocalization of eNOS with Cav-1. These results supported the hypothesis that Cav-1 mediates the action of endotoxin in suppressing ET-1-mediated eNOS activation and demonstrated that the manipulation of caveolae produces significant effects on ET-1-mediated eNOS activity in LSECs.
Cyclosporine regulates intestinal epithelial apoptosis via TGF-β-related signaling
Authors: Satoh Yuki , Ishiguro Yoh , Sakuraba Hirotake , Kawaguchi Shogo , Hiraga Hiroto , Fukuda Shinsaku , Nakane Akio
Published: July 2009

Cyclosporine is a potent immunomodulator and has a beneficial effect in the treatment of ulcerative colitis (UC). We analyzed the mechanism of the effects of cyclosporine on the regulation of epithelial apoptosis via TGF-β-related signaling, because the balance between the apoptosis and regeneration of epithelial cells seems to be a key factor to maintain the intestinal homeostasis. For this purpose, colitis was induced by treatment of 4% dextran sulfate sodium (DSS), and the effect of treatment with cyclosporine and anti-TGF-β antibody was assessed. Treatment with cyclosporine ameliorated body weight loss, mucosal destruction, and epithelial apoptosis in DSS-induced colitis. Cyclosporine was shown to upregulate the expression of TGF-β in the colonic tissue, enhance the expression of p-Smad2 and cFLIP in epithelial cells, and inhibit caspase-8 activity but not caspase-1 or -9. Upregulation of cFLIP in the colonic epithelial cells, amelioration of body weight loss, and mucosal destruction by cyclosporine were attenuated by anti-TGF-β antibody treatment. These results indicated that cyclosporine could have a protective role against epithelial apoptosis associated with upregulation of TGF-β-related signaling.
Oxidative stress in skeletal muscle impairs mitochondrial respiration and limits exercise capacity in type 2 diabetic mice
Authors: Yokota Takashi , Kinugawa Shintaro , Hirabayashi Kagami , Matsushima Shouji , Inoue Naoki , Ohta Yukihiro , Hamaguchi Sanae , Sobirin Mochamad A. , Ono Taisuke , Suga Tadashi , Kuroda Satoshi , Tanaka Shinya , Terasaki Fumio , Okita Koichi , Tsutsui Hiroyuki
Published: July 2009

Insulin resistance or diabetes is associated with limited exercise capacity, which can be caused by the abnormal energy metabolism in skeletal muscle. Oxidative stress is involved in mitochondrial dysfunction in diabetes. We hypothesized that increased oxidative stress could cause mitochondrial dysfunction in skeletal muscle and make contribution to exercise intolerance in diabetes. C57/BL6J mice were fed on normal diet or high fat diet (HFD) for 8 wk to induce obesity with insulin resistance and diabetes. Treadmill tests with expired gas analysis were performed to determine the exercise capacity and whole body oxygen uptake (V̇o2). The work (vertical distance × body weight) to exhaustion was reduced in the HFD mice by 36%, accompanied by a 16% decrease of peak V̇o2. Mitochondrial ADP-stimulated respiration, electron transport chain complex I and III activities, and mitochondrial content in skeletal muscle were decreased in the HFD mice. Furthermore, superoxide production and NAD(P)H oxidase activity in skeletal muscle were significantly increased in the HFD mice. Intriguingly, the treatment of HFD-fed mice with apocynin [10 mmol/l; an inhibitor of NAD(P)H oxidase activation] improved exercise intolerance and mitochondrial dysfunction in skeletal muscle without affecting glucose metabolism itself. The exercise capacity and mitochondrial function in skeletal muscle were impaired in type 2 diabetes, which might be due to enhanced oxidative stress. Therapies designed to regulate oxidative stress and maintain mitochondrial function could be beneficial to improve the exercise capacity in type 2 diabetes.
Maturation of O2sensing and signaling in the chicken ductus arteriosus
Authors: Cogolludo Angel L. , Moral-Sanz Javier , van der Sterren Saskia , Frazziano Giovanna , van Cleef Anne N. H. , Menéndez Carmen , Zoer Bea , Moreno Enrique , Roman Angela , Pérez-Vizcaino Francisco , Villamor Eduardo
Published: July 2009

The increase in O2tension after birth is a major factor stimulating ductus arteriosus (DA) constriction and closure. Here we studied the role of the mitochondrial electron transport chain (ETC) as sensor, H2O2as mediator, and voltage-gated potassium (KV) channels and Rho kinase as effectors of O2-induced contraction in the chicken DA during fetal development. Switching from 0% to 21% O2contracted the pulmonary side of the mature DA (mature pDA) but had no effect in immature pDA and relaxed the aortic side of the mature DA (mature aDA). This contraction of the pDA was attenuated by inhibitors of the mitochondrial ETC and by the H2O2scavenger polyethylene glycol (PEG)-catalase. Moreover, O2increased reactive oxygen species (ROS) production, measured with the fluorescent probes dihydroethidium and 2′,7′-dichlorofluorescein, only in mature pDA. The H2O2analog t-butyl-hydroperoxide mimicked the responses to O2in the three vessels. In contrast to immature pDA cells, mature pDA cells exhibited high-amplitude O2-sensitive potassium currents. The KVchannel blocker 4-aminopyridine prevented the current inhibition elicited by O2. The L-type Ca2+(CaL) channel blocker nifedipine and the Rho kinase inhibitors Y-27632 and hydroxyfasudil induced a similar relaxation when mature pDA were stimulated with O2or H2O2. Moreover, the sensitivity to these drugs increased with maturation. Our results indicate the presence of a common mechanism for O2sensing/signaling in mammalian and nonmammalian DA and favor the idea that, rather than a single mechanism, a parallel maturation of the sensor and effectors is critical for O2sensitivity appearance during development.
Genome-wide transcriptional profiling of mononuclear phagocytes recruited to mouse lungs in response to alveolar challenge with the TLR2 agonist Pam3CSK4
Authors: Cabanski Maciej , Wilhelm Jochen , Zasłona Zbigniew , Steinmüller Mirko , Fink Ludger , Seeger Werner , Lohmeyer Jürgen
Published: July 2009

Compared with the Toll-like receptor 4 (TLR4) ligand LPS restricted to Gram-negative bacteria, few studies have addressed induction of lung inflammation and concomitant leukocyte recruitment in response to TLR2 ligands. This study is the first report showing that selective TLR2 stimulation by its ligand Pam3-Cys-Ser-Lys-Lys-Lys-Lys-OH (Pam3CSK4) within the alveolar compartment promoted lung inflammation in mice and induced the migration of circulatory immune cells including mononuclear phagocytes into the inflamed alveolar space. By using the transgenic CX3CR1+/GFP mouse strain for high-purity sorting of circulating and alveolar recruited mononuclear phagocytes together with SMART preamplification and whole genome oligonucleotide microarray techniques, we found that alveolar trafficking of mononuclear phagocytes was associated with profound changes of their gene expression profiles (∼900 differentially regulated genes postrecruitment). In particular, alveolar recruited mononuclear phagocytes showed upregulated transcripts of genes encoding cytokines/chemokines and pattern recognition receptor (PRR)-associated molecules. Notably, we observed a dynamic change of the genetic program of recruited mononuclear phagocytes obtained from bronchoalveolar lavage fluid at different time points (24 vs. 48 h) post-Pam3CSK4 challenge. In early alveolar recruited mononuclear phagocytes, mRNA levels of both proinflammatory (e.g., TNF-α, CCL2, and IL-6) and central anti-inflammatory/ proresolution [e.g., IL-1-receptor antagonist (IL-1RN), CD200 receptor (CD200R), IL-1 receptor-associated kinase (IRAK-M), IL-10, and Bcl-2-associated X protein (Bax)] mediators were found to be highly upregulated simultaneously. In corresponding cells recruited until later time points, transcript levels of anti-inflammatory/proresolution molecules persisted at the same level, whereas mRNA levels of proinflammatory mediators were found to decline. Collectively, our in vivo study identifies genetic programs by which alveolar recruited mononuclear phagocytes may contribute to the development and termination of pneumonia caused by Gram-positive bacteria.
Anticipating anticipation: pursuing identification of cardiomyocyte circadian clock function
Authors: Young Martin E.
Published: July 2009

Diurnal rhythms in myocardial physiology (e.g., metabolism, contractile function) and pathophyiology (e.g., sudden cardiac death) are well establish and have classically been ascribed to time-of-day-dependent alterations in the neurohumoral milieu. Existence of an intramyocellular circadian clock has recently been exposed. Circadian clocks enable the cell to anticipate environmental stimuli, facilitating a timely and appropriate response. Generation of genetically modified mice with a targeted disruption of the cardiomyocyte circadian clock has provided an initial means for deciphering the functions of this transcriptionally based mechanism and allowed predictions regarding which environmental stimuli the heart anticipates (i.e., “anticipating anticipation”). Recent studies show that the cardiomyocyte circadian clock influences myocardial gene expression, β-adrenergic signaling, transcriptional responsiveness to fatty acids, triglyceride metabolism, heart rate, and cardiac output, as well as ischemia-reperfusion tolerance. In addition to reviewing current knowledge regarding the roles of the cardiomyocyte circadian clock, this article highlights putative frontiers in this field. The latter includes establishing molecular links between the cardiomyocyte circadian clock with identified functions, understanding the pathophysiological consequences of disruption of this mechanism, targeting resynchronization of the cardiomyocyte circadian clock for prevention/treatment of cardiovascular disease, linking the circadian clock with the cardiobeneficial effects of caloric restriction, and determining whether circadian clock genes are subject to epigenetic regulation. Information gained from studies investigating the cardiomyocyte circadian clock will likely translate to extracardiac tissues, such as skeletal muscle, liver, and adipose tissue.
Respiratory modulation of cardiovagal baroreflex sensitivity
Authors: Tzeng Y. C. , Sin P. Y. W. , Lucas S. J. E. , Ainslie P. N.
Published: July 2009

Emerging evidence has suggested that with minimal prerequisite training, slow deep breathing around 0.10 Hz can acutely enhance cardiovagal baroreflex sensitivity (BRS) in humans. Such reports have led to the speculation that behavioral interventions designed to reduce breathing frequency may serve a therapeutic role in ameliorating depressed baroreflex function in conditions such as chronic heart failure, essential hypertension, and obstructive airway disease. This study sought to test the hypothesis that slow controlled breathing acutely enhances cardiovagal baroreflex function in young healthy volunteers. Distinct from earlier studies, however, baroreflex function was examined ( n = 30) using the classical pharmacological modified Oxford method, which enabled the assessment of cardiovagal BRS through experimentally driven baroreceptor stimulation across a wide range of blood pressures. For a comparison against existing evidence, spontaneous cardiovagal BRS was also assessed using the α-index and sequence method. Compared with fast breathing (0.25 Hz), slow breathing (0.10 Hz) was associated with an increase in the α-index (8.1 ± 14 ms/mmHg, P < 0.01) and spontaneous up-sequence BRS (10 ± 11 ms/mmHg, P < 0.01). In contrast, BRS derived from spontaneous down sequences and the modified Oxford method were unaltered by slow breathing. The lack of change in BRS derived from the modified Oxford method challenges the concept that slow breathing acutely augments arterial baroreflex function in otherwise healthy humans. Our results also provide further evidence that spontaneous BRS may not reflect the BRS determined by experimentally driven baroreceptor stimulation.
Computational modeling of flow and gas exchange in models of the human maxillary sinus
Authors: Hood C. M. , Schroter R. C. , Doorly D. J. , Blenke E. J. S. M. , Tolley N. S.
Published: July 2009

The present study uses numerical modeling to increase the understanding of sinus gas exchange, which is thought to be a factor in sinus disease. Order-of-magnitude estimates and computational fluid dynamics simulations were used to investigate convective and diffusive transport between the nose and the sinus in a range of simplified geometries. The interaction between mucociliary transport and gas exchange was modeled and found to be negligible. Diffusion was the dominant transport mechanism for small ostia and large concentration differences between the sinus and the nose, whereas convection was important for larger ostia or smaller concentration differences. The presence of one or more accessory ostia can increase the sinus ventilation rate by several orders of magnitude, because it allows a net flow through the sinus. Estimates of nitric oxide (NO) transport through the ostium based on measured sinus and nasal NO concentrations suggest that the sinuses cannot supply all the NO in nasally exhaled air.
Structure and Function of HDL Mimetics
Authors: Navab Mohamad , Shechter Ishaiahu , Anantharamaiah G.M. , Reddy Srinivasa T. , Van Lenten Brian J. , Fogelman Alan M.
Published: July 2009

HDL mimetics have been constructed from a number of peptides and proteins with varying structures, all of which bind lipids found in HDL. HDL mimetics containing a peptide or protein have been constructed with as few as 4 and as many as 243 amino acid residues. Some HDL mimetics have been constructed with lipid but without a peptide or protein component. Some HDL mimetics promote cholesterol efflux, some have been shown to have a remarkable ability to bind oxidized lipids compared to human apolipoprotein A-I (apoA-I). Many of these peptides have been shown to have antiinflammatory properties. Based on studies in a number of animal models and in early human clinical trials, HDL mimetics appear to have promise as diagnostic and therapeutic agents.
Atherosclerosis in Rheumatoid Arthritis Versus Diabetes
Authors: Stamatelopoulos Kimon S. , Kitas George D. , Papamichael Christos M. , Chryssohoou Elda , Kyrkou Katerina , Georgiopoulos George , Protogerou Athanassios , Panoulas Vasileios F. , Sandoo Aamer , Tentolouris Nikolaos , Mavrikakis Myron , Sfikakis Petros P.
Published: July 2009

Objective—

The extent to which atherosclerosis is accelerated in chronic inflammatory diseases is not established. We compared preclinical atherosclerosis in rheumatoid arthritis with diabetes mellitus, a known coronary heart disease equivalent.

Methods and Results—

Endothelial function, arterial stiffness, carotid intima-media thickness, and analysis of atheromatous plaques were examined in 84 rheumatoid arthritis patients without cardiovascular disease versus healthy controls matched for age, sex, and traditional cardiovascular disease risk factors, as well as in 48 diabetes patients matched for age, sex, and disease duration with 48 rheumatoid arthritis patients. Rheumatoid arthritis duration associated with arterial stiffening, whereas disease activity associated with carotid plaque vulnerability. All markers of preclinical atherosclerosis were significantly worse in rheumatoid arthritis compared to controls, whereas they did not differ in comparison to diabetes despite a worse cardiovascular risk factor profile in diabetics. Both diseases were associated independently with increased intima-media thickness; rheumatoid arthritis, but not diabetes, was independently associated with endothelial dysfunction.

Conclusions—

Preclinical atherosclerosis appears to be of equal frequency and severity in rheumatoid arthritis and diabetes of similar duration with differential impact of traditional risk factors and systemic inflammation. Cardiovascular disease risk factors in rheumatoid arthritis may need to be targeted as aggressively as in diabetes.
Knockout of p47
phox
Uncovers a Critical Role of p40
phox
in Reactive Oxygen Species Production in Microvascular Endothelial Cells
Authors: Fan Lampson M. , Teng Lei , Li Jian-Mei
Published: July 2009

Objective—

p40
phox
is an important regulatory subunit of NADPH oxidase, but its role in endothelial reactive oxygen species (ROS) production remains unknown.

Methods and Results—

Using coronary microvascular endothelial cells isolated from wild-type and p47
phox
knockout mice, we found that knockout of p47
phox
increased the level of p40
phox
expression, whereas depletion of p40
phox
in wild-type cells increased p47
phox
expression. In both cases, the basal ROS production (without agonist stimulation) was well preserved. Double knockout of p40
phox
and p47
phox
dramatically reduced (≈65%) ROS production and cells started to die. The transcriptional regulation of p40
phox
and p47
phox
expressions involves HBP1. p40
phox
was prephosphorylated in resting cells. PMA stimulation induced p40
phox
swift dephosphorylation (within 1 minute) in parallel with the start of p47
phox
phosphorylation. p40
phox
was then rephosphorylated, and this was accompanied with an increase in ROS production. Depletion of p40
phox
resulted in ≈67% loss in agonist-induced ROS production despite the presence of p47
phox
. These were further supported by experiments on mouse aortas stimulated with angiotensin II.

Conclusion—

p40
phox
is prephosphorylated in resting endothelial cells and can compensate p47
phox
in keeping basal ROS production. Dephosphorylation of p40
phox
is a prerequisite for agonist-induced p47
phox
phosphorylation, and p40
phox
through its dynamic dephosphorylation and rephosphorylation is involved in the regulation of agonist-induced ROS production.
Dietary Cholesterol Plays a Role in CD36-Mediated Atherogenesis in LDLR-Knockout Mice
Authors: Kennedy David J. , Kuchibhotla Sai D. , Guy Ella , Park Young Mi , Nimako George , Vanegas DiFernando , Morton Richard E. , Febbraio Maria
Published: July 2009

Objective—

CD36 has been shown to play a role in atherosclerosis in the apolipoprotein E-knockout (

apoE
o

) mouse. We observed no difference in aortic lesion area between Western diet (WD)-fed
LDLR
o
and
LDLR
o
/
CD36
o
mice. The objective was to understand the mechanism of CD36-dependent atherogenesis.

Methods and Results—

A
poE
o
mice transplanted with bone marrow from
LDLR
o
/
CD36
o
mice had significantly less aortic lesion compared with those transplanted with
LDLR
o
marrow. Reciprocal macrophage transfer into hyperlipidemic

apoE
o

and

LDLR
o

animals showed that foam cell formation induced by in vivo modified lipoproteins was dependent on the lipoprotein, not macrophage type.
LDLR
o
and
LDLR
o
/
CD36
o
mice were fed a cholesterol-enriched diet (HC), and we observed significant lesion inhibition in
LDLR
o
/
CD36
o
mice. LDL/plasma isolated from HC-fed

LDLR
o

mice induced significantly greater
jnk
phosphorylation, cytokine release, and reactive oxygen species secretion than LDL/plasma from WD-fed

LDLR
o

mice, and this was CD36-dependent. HC-fed

LDLR
o

mice had higher circulating levels of cytokines than WD-fed mice.

Conclusions—

These data support the hypothesis that CD36-dependent atherogenesis is contingent on a proinflammatory milieu that promotes the creation of specific CD36 ligands, not solely hypercholesterolemia, and may explain the greater degree/accelerated rate of atherosclerosis observed in syndromes associated with inflammatory risk.
Sphingosine-1-Phosphate Receptor-2 Regulates Expression of Smooth Muscle Alpha-Actin After Arterial Injury
Authors: Grabski Allison D. , Shimizu Takuya , Deou Jessie , Mahoney William M. , Reidy Michael A. , Daum Guenter
Published: July 2009

Objective—

This study tests the hypothesis that S1P2R regulates expression of SMC differentiation genes after arterial injury.

Methods and Results—

Carotid ligation injury was performed in wild-type and S1P2R-null mice. At various time points after injury, expression of multiple SMC differentiation genes, myocardin, and S1P receptors (S1P1R, S1P2R, and S1P3R) was measured by quantitative PCR. These experiments demonstrate that at day 7 after injury, S1P2R specifically regulates expression of smooth muscle α-actin (SMA) and that this is not mediated by changes in expression of myocardin or any of the S1PRs. In vitro studies using carotid SMCs prepared from wild-type and S1P2R-null mice show that S1P stimulates expression of all SMC-differentiation genes tested, but S1P2R significantly regulates expression of SMA and SM22α only. Chromatin immunoprecipitation assays suggest that S1P-induced recruitment of serum response factor to the SMA promoter and enhancer largely depends on S1P2R. S1P-stimulated SMA expression requires S1P2R-dependent activation of RhoA and mobilization of calcium from intracellular stores. Chelation of calcium does not affect the activation of RhoA by S1P, whereas blockade of Rho by C3 exotoxin partially inhibits the mobilization of calcium by S1P.

Conclusions—

The results of this study support the hypothesis that S1P2R regulates expression of SMA after injury. We further conclude that transcriptional regulation of SMA by S1P in vitro requires S1P2R-dependent activation of RhoA and mobilization of calcium from intracellular calcium stores.
Estrogen Receptor α Expression in Both Endothelium and Hematopoietic Cells Is Required for the Accelerative Effect of Estradiol on Reendothelialization
Authors: Toutain Céline E. , Filipe Cédric , Billon Audrey , Fontaine Coralie , Brouchet Laurent , Guéry Jean-Charles , Gourdy Pierre , Arnal Jean-François , Lenfant Françoise
Published: July 2009

Objectives—

E2 accelerates reendothelialization through estrogen receptor α (ERα), and we now aimed at defining the precise local and systemic cellular actors of this process.

Methods and Results—

The respective roles of endothelial and hematopoietic targets of E2 were investigated in a mouse carotid injury model, using confocal microscopy, to follow endothelium repair. Grafting ERα
−/−
mice with ERα
+/+
bone marrow (BM) was not sufficient to restore the accelerative effect of E2 on reendothelialization, demonstrating the necessary role of extrahematopoietic ERα. Using an endothelial-specific inactivation of ERα (Cre-Lox system), we showed that endothelial ERα plays a pivotal role in this E2 action. Conversely, in ERα
+/+
grafted with ERα
−/−
BM, the E2 regenerative effect was abolished, demonstrating that ERα-expressing hematopoietic cells are also needed. As eNOS expression in BM was required for this action, both endothelial progenitor cells and platelets could be the hematopoietic targets that participate to this beneficial E2 effect.

Conclusions—

We demonstrate that endothelial ERα plays a pivotal role in E2-mediated reendothelialization. However, endothelial targeting alone is not sufficient because the concomitant stimulation of a subpopulation of BM ERα is necessary. This cooperation should be taken into account in strategies aimed at optimizing in-stent reendothelialization.
Hybrid In Vivo FMT-CT Imaging of Protease Activity in Atherosclerosis With Customized Nanosensors
Authors: Nahrendorf Matthias , Waterman Peter , Thurber Greg , Groves Kevin , Rajopadhye Milind , Panizzi Peter , Marinelli Brett , Aikawa Elena , Pittet Mikael J. , Swirski Filip K. , Weissleder Ralph
Published: July 2009

Objective—

Proteases are emerging biomarkers of inflammatory diseases. In atherosclerosis, these enzymes are often secreted by inflammatory macrophages, digest the extracellular matrix of the fibrous cap, and destabilize atheromata. Protease function can be monitored with protease activatable imaging probes and quantitated in vivo by fluorescence molecular tomography (FMT). To address 2 major constraints currently associated with imaging of murine atherosclerosis (lack of highly sensitive probes and absence of anatomic information), we compared protease sensors (PS) of variable size and pharmacokinetics and coregistered FMT datasets with computed tomography (FMT-CT).

Methods and Results—

Coregistration of FMT and CT was achieved with a multimodal imaging cartridge containing fiducial markers detectable by both modalities. A high-resolution CT angiography protocol accurately localized fluorescence to the aortic root of atherosclerotic apoE
−/−
mice. To identify suitable sensors, we first modeled signal kinetics in-silico and then compared 3 probes with oligo-
l
-lysine cleavage sequences: PS-5, 5 nm in diameter containing 2 fluorochromes, PS-25, a 25-nm version with an elongated lysine chain and PS-40, a polymeric nanoparticle. Serial FMT-CT showed fastest kinetics for PS-5 but, surprisingly, highest fluorescence in lesions of the aortic root for PS-40. PS-40 robustly reported therapeutic effects of atorvastatin, corroborated by ex vivo imaging and qPCR for the model protease cathepsin B.

Conclusions—

FMT-CT is a robust and observer-independent tool for noninvasive assessment of inflammatory murine atherosclerosis. Reporter-containing nanomaterials may have unique advantages over small molecule agents for in vivo imaging.
Ccl2 and Ccl3 Mediate Neutrophil Recruitment via Induction of Protein Synthesis and Generation of Lipid Mediators
Authors: Reichel Christoph Andreas , Rehberg Markus , Lerchenberger Max , Berberich Nina , Bihari Peter , Khandoga Alexander Georg , Zahler Stefan , Krombach Fritz
Published: July 2009

Objective—

Although the chemokines monocyte chemoattractant protein-1 (Ccl2/JE/MCP-1) and macrophage inflammatory protein-1α (Ccl3/MIP-1α) have recently been implicated in neutrophil migration, the underlying mechanisms remain largely unclear.

Methods and Results—

Stimulation of the mouse cremaster muscle with Ccl2/JE/MCP-1 or Ccl3/MIP-1α induced a significant increase in numbers of firmly adherent and transmigrated leukocytes (>70% neutrophils) as observed by in vivo microscopy. This increase was significantly attenuated in mice receiving an inhibitor of RNA transcription (actinomycin D) or antagonists of platelet activating factor (PAF; BN 52021) and leukotrienes (MK-886; AA-861). In contrast, leukocyte responses elicited by PAF and leukotriene-B
4
(LTB
4
) themselves were not affected by actinomycin D, BN 52021, MK-886, or AA-861. Conversely, PAF and LTB
4
, but not Ccl2/JE/MCP-1 and Ccl3/MIP-1α, directly activated neutrophils as indicated by shedding of CD62L and marked upregulation of CD11b. Moreover, Ccl2/JE/MCP-1- and Ccl3/MIP-1α-elicited leakage of fluorescein isothiocyanate dextran as well as collagen IV remodeling within the venular basement membrane were completely absent in neutrophil-depleted mice.

Conclusions—

Ccl2/JE/MCP-1 and Ccl3/MIP-1α mediate firm adherence and (subsequent) transmigration of neutrophils via protein synthesis and secondary generation of leukotrienes and PAF, which in turn directly activate neutrophils. Thereby, neutrophils facilitate basement membrane remodeling and promote microvascular leakage.
Estrogen Contributes to Gender Differences in Mouse Ventricular Repolarization
Authors: Saito Tomoaki , Ciobotaru Andrea , Bopassa Jean Chrisostome , Toro Ligia , Stefani Enrico , Eghbali Mansoureh
Published: July 2009

Rationale:

Fast-transient outward K
+
(
I
to,f
) and ultrarapid delayed rectifier K
+
currents (
I
K,slow
, also known as
I
Kur
) contribute to mouse cardiac repolarization. Gender studies on these currents have reported conflicting results.

Objective:

Key missing information in these studies is the estral stage of the animals. We revisited gender-related differences in K
+
currents, taking into consideration the females’ estral stage. We hypothesized that changes in estrogen levels during the estral cycle could play a role in determining the densities of K
+
currents underlying ventricular repolarization.

Methods and Results:

Peak total K
+
current (
I
K,total
) densities (pA/pF, at +40 mV) were much higher in males (48.6±3.0) versus females at estrus (27.2±2.3) but not at diestrus-2 (39.1±3.4). Underlying this change,
I
to,f
and
I
K,slow
were lower in females at estrus versus males and diestrus-2 (
I
K,slow
: male 21.9±1.8, estrus 14.6±0.6, diestrus-2 20.3±1.4;
I
to,f
: male 26.8±1.9, estrus 14.9±1.6, diestrus-2 22.1±2.1). Lower
I
K,slow
in estrus was attributable to only
I
K,slow
1
reduction, without changes in
I
K,slow
2
. Estrogen treatment of ovariectomized mice decreased
I
K,total
(46.4±3.0 to 28.4±1.6),
I
to,f
(26.6±1.6 to 12.8±1.0) and
I
K,slow
(22.2±1.6 to 17.2±1.4). Transcript levels of Kv4.3 and Kv1.5 (underlying
I
to,f
and
I
K,slow
, respectively) were lower in estrus versus diestrus-2 and male. In ovariectomized mice, estrogen treatment resulted in downregulation of Kv4.3 and Kv1.5 but not Kv4.2, KChIP2, or Kv2.1 transcripts. K
+
current reduction in high estrogenic conditions were associated with prolongation of the action potential duration and corrected QT interval.

Conclusion:

Downregulation of Kv4.3 and Kv1.5 transcripts by estrogen are one mechanism defining gender-related differences in mouse ventricular repolarization.
Predicting Tissue Outcome From Acute Stroke Magnetic Resonance Imaging
Authors: Jonsdottir Kristjana Yr , Østergaard Leif , Mouridsen Kim
Published: July 2009

Background and Purpose—

It has been hypothesized that algorithms predicting the final outcome in acute ischemic stroke may provide future tools for identifying salvageable tissue and hence guide individualized therapy. We developed means of quantifying predictive model performance to identify model training strategies that optimize performance and reduce bias in predicted lesion volumes.

Methods—

We optimized predictive performance based on the area under the receiver operating curve for logistic regression and used simulated data to illustrate the effect of an unbalanced (unequal number of infarcting and surviving voxels) training set on predicted infarct risk. We then tested the performance and optimality of models based on perfusion-weighted, diffusion-weighted, and structural MRI modalities by changing the proportion of mismatch voxels in balanced training material.

Results—

Predictive performance (area under the receiver operating curve) based on all brain voxels is excessively optimistic and lacks sensitivity in performance in mismatch tissue. The ratio of infarcting and noninfarcting voxels used for training predictive algorithms significantly biases tissue infarct risk estimates. Optimal training strategy is obtained using a balanced training set. We show that 60% of noninfarcted voxels consists of mismatch voxels in an optimal balanced training set for the patient data presented.

Conclusions—

An equal number of infarcting and noninfarcting voxels should be used when training predictive models. The choice of test and training sets critically affects predictive model performance and should be closely evaluated before comparisons across patient cohorts.
Delay in the Diagnosis of Cerebral Vein and Dural Sinus Thrombosis
Authors: Ferro José M. , Canhão Patrícia , Stam Jan , Bousser Marie-Germaine , Barinagarrementeria Fernando , Massaro Ayrton , Ducrocq Xavier , Kasner Scott E.
Published: July 2009

Background and Purpose—

Diagnostic delay of cerebral vein and dural sinus thrombosis may have an impact on outcome.

Methods—

In the International Study on Cerebral Vein and Dural Sinus Thrombosis (ISCVT) cohort (624 patients with cerebral vein and dural sinus thrombosis), we analyzed the predictors and the impact on outcome of diagnostic delay. Primary outcome was a modified Rankin Scale score >2 at the end of follow-up. Secondary outcomes were modified Rankin Scale score 0 to 1 at the end of follow-up, death, and visual deficits (visual acuity or visual field).

Results—

Median delay was 7 days (interquartile range, 3 to 16). Patients with disturbance of consciousness (
P
<0.001) and of mental status (
P
=0.042), seizure (<0.001), and with parenchymal lesions on admission CT/MR (
P
<0.001) were diagnosed earlier, whereas men (
P
=0.01) and those with isolated intracranial hypertension syndrome (
P
=0.04) were diagnosed later. Between patients diagnosed earlier and later than the median delay, no statistically significant differences were found in the primary (
P
=0.33) and in secondary outcomes: modified Rankin Scale score 0 to 1 (
P
=0.86) or deaths (
P
=0.53). Persistent visual deficits were more frequent in patients diagnosed later (
P
=0.05). In patients with isolated intracranial hypertension syndrome, modified Rankin Scale score >2 at the end of follow-up was more frequent in patients diagnosed later (
P
=0.02).

Conclusions—

Diagnostic delay was considerable in this cohort and was associated with an increased risk of visual deficit. In patients with isolated intracranial hypertension syndrome, diagnostic delay was also associated with death or dependency.