bluuebunny/crossref_metadata_2025 huggingface dataset:
Oral glutamine supplementation improves intestinal permeability dysfunction in a murine acute graft-vs.-host disease model
Authors: Noth Rainer , Häsler Robert , Stüber Eckhard , Ellrichmann Mark , Schäfer Heiner , Geismann Claudia , Hampe Jochen , Bewig Burkhard , Wedel Thilo , Böttner Martina , Schreiber Stefan , Rosenstiel Philip , Arlt Alexander
Published: February 2013

Although a profound barrier dysfunction has been reported, little is known about the pathophysiological mechanism evoking gastrointestinal graft-vs.-host disease (GI-GvHD) and apparent therapeutic options. The aim of this study was to evaluate the influence of oral glutamine on the course of GI-GvHD in an acute semiallogenic graft-vs.-host disease (GvHD) in irradiated B6D2F1 mice. An acute semiallogenic GvHD was induced by intraperitoneal injection of lymphocytes from C57BL/6 mice to irradiated B6D2F1 mice. Half of the GvHD animals received oral glutamine supplementation for 6 days started at the time of lymphocyte transfer. Six days after induction of the semiallogenic GvHD, jejunum specimens were prepared. The expression of the proinflammatory cytokine TNF-α and the tight junction protein occludin was investigated by PCR. Histological changes along with the apoptotic response were evaluated and intestinal permeability was assessed. Animals with GvHD showed a strong increase in paracellular permeability as a sign of the disturbed barrier function. TNF-α expression was significantly increased and the expression of the tight junction protein occludin decreased. GvHD led to mucosal atrophy, crypt hyperplasia, crypt apoptosis, and a disintegration of the tight junctions. Glutamine-treated mice showed reduced expression of TNF-α, increased occludin expression, fewer histological changes in the jejunum, smaller number of apoptotic cells in the crypt, and reduced gastrointestinal permeability. In conclusion, oral glutamine seems to have beneficial effects on the severity of inflammatory changes in the course of GvHD and might be a therapeutic option.
Endocytic pathway of exogenous iron-loaded ferritin in intestinal epithelial (Caco-2) cells
Authors: Antileo Elmer , Garri Carolina , Tapia Victoria , Muñoz Juan Pablo , Chiong Mario , Nualart Francisco , Lavandero Sergio , Fernández Juan , Núñez Marco T.
Published: February 2013

Ferritin, a food constituent of animal and vegetal origin, is a source of dietary iron. Its hollow central cavity has the capacity to store up to 4,500 atoms of iron, so its potential as an iron donor is advantageous to heme iron, present in animal meats and inorganic iron of mineral or vegetal origin. In intestinal cells, ferritin internalization by endocytosis results in the release of its iron into the cytosolic labile iron pool. The aim of this study was to characterize the endocytic pathway of exogenous ferritin absorbed from the apical membrane of intestinal epithelium Caco-2 cells, using both transmission electron microscopy and fluorescence confocal microscopy. Confocal microscopy revealed that endocytosis of exogenous AlexaFluor 488-labeled ferritin was initiated by its engulfment by clathrin-coated pits and internalization into early endosomes, as determined by codistribution with clathrin and early endosome antigen 1 (EEA1). AlexaFluor 488-labeled ferritin also codistributed with the autophagosome marker microtubule-associated protein 1 light chain 3 (LC3) and the lysosome marker lysosomal-associated membrane protein 2 (LAMP2). Transmission electron microscopy revealed that exogenously added ferritin was captured in plasmalemmal pits, double-membrane compartments, and multivesicular bodies considered as autophagosomes and lysosomes. Biochemical experiments revealed that the lysosome inhibitor chloroquine and the autophagosome inhibitor 3-methyladenine (3-MA) inhibited degradation of exogenously added131I-labeled ferritin. This evidence is consistent with a model in which exogenous ferritin is internalized from the apical membrane through clathrin-coated pits, and then follows a degradation pathway consisting of the passage through early endosomes, autophagosomes, and autolysosomes.
Digenic inheritance novel mutations in SCN5a and SNTA1 increase late INa contributing to LQT syndrome
Authors: Hu Rou-Mu , Tan Bi-Hua , Orland Kate M. , Valdivia Carmen R. , Peterson Amber , Pu Jielin , Makielski Jonathan C.
Published: February 2013

SCN5A and SNTA1 are reported susceptible genes for long QT syndrome (LQTS). This study was designed to elucidate a plausible pathogenic arrhythmia mechanism for the combined novel mutations R800L-SCN5A and A261V-SNTA1 on cardiac sodium channels. A Caucasian family with syncope and marginally prolonged QT interval was screened for LQTS-susceptibility genes and found to harbor the R800L mutation in SCN5A and A261V mutation in SNTA1, and those with both mutations had the strongest clinical phenotype. The mutations were engineered into the most common splice variant of human SCN5A and SNTA1 cDNA, respectively, and sodium current ( INa) was characterized in human embryonic kidney 293 cells cotransfected with neuronal nitric oxide synthase (nNOS) and the cardiac isoform of the plasma membrane Ca-ATPase (PMCA4b). Peak INa densities were unchanged for wild-type (WT) and for mutant channels containing R800L-SCN5A, A261V-SNTA1, or R800L-SCN5A plus A261V-SNTA1. However, late INa for either single mutant was moderately increased two- to threefold compared with WT. The combined mutations of R800L-SCN5A plus A261V-SNTA1 significantly enhanced the INa late/peak ratio by 5.6-fold compared with WT. The time constants of current decay of combined mutant channel were markedly increased. The gain-of-function effect could be blocked by the NG-monomethyl-l-arginine, a nNOS inhibitor. We conclude that novel mutations in SCN5A and SNTA1 jointly exert a nNOS-dependent gain-of-function on SCN5A channels, which may consequently prolong the action potential duration and lead to LQTS phenotype.
Hydrogen sulfide in the mouse ductus arteriosus: a naturally occurring relaxant with potential EDHF function
Authors: Baragatti Barbara , Ciofini Enrica , Sodini Daria , Luin Stefano , Scebba Francesca , Coceani Flavio
Published: February 2013

We have previously reported that bradykinin relaxes the fetal ductus arteriosus via endothelium-derived hyperpolarizing factor (EDHF) when other naturally occurring relaxants (prostaglandin E2, nitric oxide, and carbon monoxide) are suppressed, but the identity of the agent could not be ascertained. Here, we have examined in the mouse whether hydrogen sulfide (H2S) is a relaxant of the ductus and, if so, whether it may also function as an EDHF. We found in the vessel transcripts for the H2S synthetic enzymes, cystathionine-γ-lyase (CSE) and cystathionine-β-synthase (CBS), and the presence of these enzymes was confirmed by immunofluorescence microscopy. CSE and CBS were distributed across the vessel wall with the former prevailing in the intimal layer. Both enzymes occurred within the endoplasmic reticulum of endothelial and muscle cells, whereas only CSE was located also in the plasma membrane. The isolated ductus contracted to inhibitors of CSE (d,l-propargylglycine, PPG) and CBS (amino-oxyacetic acid), and PPG contraction was attenuated by removal of the endothelium. EDHF-mediated bradykinin relaxation was curtailed by both PPG and amino-oxyacetic acid, whereas the relaxation to sodium nitroprusside was not affected by either treatment. The H2S donor sodium hydrogen sulfide (NaHS) was also a potent, concentration-dependent relaxant. We conclude that the ductus is endowed with a H2S system exerting a tonic relaxation. In addition, H2S, possibly via an overriding CSE source, qualifies as an EDHF. These findings introduce a novel vasoregulatory mechanism into the ductus, with implications for antenatal patency of the vessel and its transitional adjustments at birth.
Mechanisms of striated muscle dysfunction during acute exacerbations of COPD
Authors: Gayan-Ramirez Ghislaine , Decramer Marc
Published: February 2013

During acute exacerbations of chronic obstructive pulmonary disease (COPD), limb and respiratory muscle dysfunction develops rapidly and functional recovery is partial and slow. The mechanisms leading to this muscle dysfunction are not yet fully established. However, recent evidence has shown that several pathways involved in muscle catabolism, apoptosis, and oxidative stress are activated in the vastus lateralis muscle of patients during acute exacerbations of COPD, while those implicated in mitochondrial function are downregulated. These pathways may be targeted in different ways by factors related to exacerbations. These factors include enhanced systemic inflammation, oxidative stress, impaired energy balance, hypoxia, hypercapnia and acidosis, corticosteroid treatment, and physical inactivity. Data on the respiratory muscles are limited, but these muscles are undoubtedly overloaded during exacerbations. While they are also subjected to the same systemic elements as the limb muscles (except for inactivity), they also face a specific mechanical disadvantage caused by changes in lung volume during exacerbation. The latter will affect the ability to generate force by the foreshortening of the muscle (especially for the diaphragm), but also by altering rib orientation and motion (especially for the parasternal intercostals and the external intercostals). Because acute exacerbations of COPD are associated with an increase in both prevalence and severity of generalized muscle dysfunction, and both remain present even during recovery, early interventions to minimize muscle dysfunction during exacerbation are warranted. Although rehabilitation may be promising, other therapeutic strategies such as counterbalancing the adverse effects of exacerbations on skeletal muscle pathways may also be used.
Acute high-intensity endurance exercise is more effective than moderate-intensity exercise for attenuation of postprandial triglyceride elevation
Authors: Trombold Justin R. , Christmas Kevin M. , Machin Daniel R. , Kim Il-Young , Coyle Edward F.
Published: February 2013

Acute exercise has been shown to attenuate postprandial plasma triglyceride elevation (PPTG). However, the direct contribution of exercise intensity is less well understood. The purpose of this study was to examine the effects of exercise intensity on PPTG and postprandial fat oxidation. One of three experimental treatments was performed in healthy young men ( n = 6): nonexercise control (CON), moderate-intensity exercise (MIE; 50% V̇o2peak for 60 min), or isoenergetic high-intensity exercise (HIE; alternating 2 min at 25% and 2 min at 90% V̇o2peak). The morning after the exercise, a standardized meal was provided (16 kcal/kg BM, 1.02 g fat/kg, 1.36 g CHO/kg, 0.31 g PRO/kg), and measurements of plasma concentrations of triglyceride (TG), glucose, insulin, and β-hydroxybutyrate were made in the fasted condition and hourly for 6 h postprandial. Indirect calorimetry was used to determine fat oxidation in the fasted condition and 2, 4, and 6 h postprandial. Compared with CON, both MIE and HIE significantly attenuated PPTG [incremental AUC; 75.2 (15.5%), P = 0.033, and 54.9 (13.5%), P = 0.001], with HIE also significantly lower than MIE ( P = 0.03). Postprandial fat oxidation was significantly higher in MIE [83.3 (10.6%) of total energy expenditure] and HIE [89.1 (9.8) %total] compared with CON [69.0 (16.1) %total, P = 0.039, and P = 0.018, respectively], with HIE significantly greater than MIE ( P = 0.012). We conclude that, despite similar energy expenditure, HIE was more effective than MIE for lowering PPTG and increasing postprandial fat oxidation.
mTOR signaling response to resistance exercise is altered by chronic resistance training and detraining in skeletal muscle
Authors: Ogasawara Riki , Kobayashi Koji , Tsutaki Arata , Lee Kihyuk , Abe Takashi , Fujita Satoshi , Nakazato Koichi , Ishii Naokata
Published: February 2013

Resistance training-induced muscle anabolism and subsequent hypertrophy occur most rapidly during the early phase of training and become progressively slower over time. Currently, little is known about the intracellular signaling mechanisms underlying changes in the sensitivity of muscles to training stimuli. We investigated the changes in the exercise-induced phosphorylation of hypertrophic signaling proteins during chronic resistance training and subsequent detraining. Male rats were divided into four groups: 1 bout (1B), 12 bouts (12B), 18 bouts (18B), and detraining (DT). In the DT group, rats were subjected to 12 exercise sessions, detrained for 12 days, and then were subjected to 1 exercise session before being killed. Isometric training consisted of maximum isometric contraction, which was produced by percutaneous electrical stimulation of the gastrocnemius muscle every other day. Muscles were removed 24 h after the final exercise session. Levels of total and phosphorylated p70S6K, 4E-BP1, rpS6, and p90RSK levels were measured, and phosphorylation of p70S6K, rpS6, and p90RSK was elevated in the 1B group compared with control muscle (CON) after acute resistance exercise, whereas repeated bouts of exercise suppressed those phosphorylation in both 12B and 18B groups. Interestingly, these phosphorylation levels were restored after 12 days of detraining in the DT group. On the contrary, phosphorylation of 4E-BP1 was not altered with chronic training and detraining, indicating that, with chronic resistance training, anabolic signaling becomes less sensitive to resistance exercise stimuli but is restored after a short detraining period.
Cerebral critical closing pressure and CO2 responses during the progression toward syncope
Authors: Zuj K. A. , Arbeille P. , Shoemaker J. K. , Hughson R. L.
Published: February 2013

Syncope from sustained orthostasis results from cerebral hypoperfusion associated with reductions in arterial pressure at the level of the brain (BPMCA) and reductions in arterial CO2 as reflected by end-tidal values (PetCO2). It was hypothesized that reductions in PetCO2 increase cerebrovascular tone before a drop in BPMCA that ultimately leads to syncope. Twelve men (21–42 yr of age) completed an orthostatic tolerance test consisting of head-up tilt and progressive lower body negative pressure to presyncope, before and after completing 5 days of continuous head-down bed rest (HDBR). Cerebral blood velocity (CBFV), BPMCA, and PetCO2 were continuously recorded throughout the test. Cerebrovascular indicators, cerebrovascular resistance, critical closing pressure (CrCP), and resistance area product (RAP), were calculated. Comparing from supine baseline to 6–10 min after the start of tilt, there were reductions in CBFV, PetCO2, BPMCA, and CrCP, an increase in RAP, and no change in cerebrovascular resistance index. Over the final 15 min before syncope in the pre-HDBR tests, CBFV and CrCP were significantly related to changes in PetCO2 ( r = 0.69 ± 0.17 and r = 0.63 ± 0.20, respectively), and BPMCA, which was not reduced until the last minute of the test, was correlated with a reduction in RAP ( r = 0.91 ± 0.09). Post-HDBR, tilt tolerance was markedly reduced, and changes in CBFV were dominated by a greater reduction in BPMCA with no relationships to PetCO2. Therefore, pre-HDBR, changes in PetCO2 with orthostasis contributed to increases in cerebrovascular tone and reductions in CBFV during the progression toward syncope, whereas, after 5 days of HDBR, orthostatic responses were dominated by changes in BPMCA.
Effect of methacholine on peripheral lung mechanics and ventilation heterogeneity in asthma
Authors: Downie Sue R. , Salome Cheryl M. , Verbanck Sylvia , Thompson Bruce R. , Berend Norbert , King Gregory G.
Published: February 2013

The forced oscillation technique (FOT) and multiple-breath nitrogen washout (MBNW) are noninvasive tests that are potentially sensitive to peripheral airways, with MBNW indexes being especially sensitive to heterogeneous changes in ventilation. The objective was to study methacholine-induced changes in the lung periphery of asthmatic patients and determine how changes in FOT variables of respiratory system reactance (Xrs) and resistance (Rrs) and frequency dependence of resistance (Rrs5-Rrs19) can be linked to changes in ventilation heterogeneity. The contributions of air trapping and airway closure, as extreme forms of heterogeneity, were also investigated. Xrs5, Rrs5, Rrs19, Rrs5-Rrs19, and inspiratory capacity (IC) were calculated from the FOT. Ventilation heterogeneity in acinar and conducting airways, and trapped gas (percent volume of trapped gas at functional residual capacity/vital capacity), were calculated from the MBNW. Measurements were repeated following methacholine. Methacholine-induced airway closure (percent change in forced vital capacity) and hyperinflation (change in IC) were also recorded. In 40 mild to moderate asthmatic patients, increase in Xrs5 after methacholine was predicted by increases in ventilation heterogeneity in acinar airways and forced vital capacity ( r2 = 0.37, P < 0.001), but had no correlation with ventilation heterogeneity in conducting airway increase or IC decrease. Increases in Rrs5 and Rrs5-Rrs19 after methacholine were not correlated with increases in ventilation heterogeneity, trapped gas, hyperinflation, or airway closure. Increased reactance in asthmatic patients after methacholine was indicative of heterogeneous changes in the lung periphery and airway closure. By contrast, increases in resistance and frequency dependence of resistance were not related to ventilation heterogeneity or airway closure and were more indicative of changes in central airway caliber than of heterogeneity.
Sirtuin-1 Regulates Acinar-to-Ductal Metaplasia and Supports Cancer Cell Viability in Pancreatic Cancer
Authors: Wauters Elke , Sanchez-Arévalo Lobo Victor J. , Pinho Andreia V. , Mawson Amanda , Herranz Daniel , Wu Jianmin , Cowley Mark J. , Colvin Emily K. , Njicop Erna Ngwayi , Sutherland Rob L. , Liu Tao , Serrano Manuel , Bouwens Luc , Real Francisco X. , Biankin Andrew V. , Rooman Ilse
Published: February 2013

The exocrine pancreas can undergo acinar-to-ductal metaplasia (ADM), as in the case of pancreatitis where precursor lesions of pancreatic ductal adenocarcinoma (PDAC) can arise. The NAD+-dependent protein deacetylase Sirtuin-1 (Sirt1) has been implicated in carcinogenesis with dual roles depending on its subcellular localization. In this study, we examined the expression and the role of Sirt1 in different stages of pancreatic carcinogenesis, i.e. ADM models and established PDAC. In addition, we analyzed the expression of KIAA1967, a key mediator of Sirt1 function, along with potential Sirt1 downstream targets. Sirt1 was co-expressed with KIAA1967 in the nuclei of normal pancreatic acinar cells. In ADM, Sirt1 underwent a transient nuclear-to-cytoplasmic shuttling. Experiments where during ADM, we enforced repression of Sirt1 shuttling, inhibition of Sirt1 activity or modulation of its expression, all underscore that the temporary decrease of nuclear and increase of cytoplasmic Sirt1 stimulate ADM. Our results further underscore that important transcriptional regulators of acinar differentiation, that is, Pancreatic transcription factor-1a and β-catenin can be deacetylated by Sirt1. Inhibition of Sirt1 is effective in suppression of ADM and in reducing cell viability in established PDAC tumors. KIAA1967 expression is differentially downregulated in PDAC and impacts on the sensitivity of PDAC cells to the Sirt1/2 inhibitor Tenovin-6. In PDAC, acetylation of β-catenin is not affected, unlike p53, a well-characterized Sirt1-regulated protein in tumor cells. Our results reveal that Sirt1 is an important regulator and potential therapeutic target in pancreatic carcinogenesis. Cancer Res; 73(7); 2357–67. ©2012 AACR.
Prevalence and Healthcare Actions of Women in a Large Health System with a Family History Meeting the 2005 USPSTF Recommendation for BRCA Genetic Counseling Referral
Authors: Bellcross Cecelia A. , Leadbetter Steven , Alford Sharon Hensley , Peipins Lucy A.
Published: February 2013

Background: In 2005, the United States Preventive Services Task Force (USPSTF) released guidelines which outlined specific family history patterns associated with an increased risk for BRCA1/2 mutations, and recommended at-risk individuals be referred for genetic counseling and evaluation for BRCA testing. The purpose of this study was to assess the prevalence of individuals with a USPSTF increased-risk family history pattern, the frequency with which specific patterns were met, and resulting healthcare actions among women from the Henry Ford Health System.

Methods: As part of a study evaluating ovarian cancer risk perception and screening, 2,524 randomly selected participants completed a detailed interview (response rate 76%) from an initial eligible cohort of 16,720 women.

Results: Approximately 6% of participants had a family history fulfilling one or more of the USPSTF patterns. Although 90% of these women had shared their family history with their provider, less than 20% had been referred for genetic counseling and only 8% had undergone genetic testing. Caucasian women with higher income and education levels were more likely to receive referrals. Among the 95 participants in the total study cohort who reported BRCA testing, 78% did not have a family history that met one of the USPSTF patterns.

Conclusions: These results suggest a higher prevalence of women with an increased-risk family history than originally predicted by the USPSTF, and lack of provider recognition and referral for genetic services.

Impact: Improvements in healthcare infrastructure and clinician education will be required to realize population level benefits from BRCA genetic counseling and testing. Cancer Epidemiol Biomarkers Prev; 22(4); 728–35. ©2013 AACR.
EGFR Exon 20 Insertion Mutations in Lung Adenocarcinomas: Prevalence, Molecular Heterogeneity, and Clinicopathologic Characteristics
Authors: Arcila Maria E. , Nafa Khedoudja , Chaft Jamie E. , Rekhtman Natasha , Lau Christopher , Reva Boris A. , Zakowski Maureen F. , Kris Mark G. , Ladanyi Marc
Published: February 2013

In contrast to other primary epidermal growth factor receptor (EGFR) mutations in lung adenocarcinomas, insertions in exon 20 of EGFR have been generally associated with resistance to EGFR-tyrosine kinase inhibitors. Their molecular spectrum, clinicopathologic characteristics, and prevalence are not well established. Tumors harboring EGFR exon 20 insertions were identified through an algorithmic screen of 1,500 lung adenocarcinomas. Cases were first tested for common mutations in EGFR (exons 19 and 21) and KRAS (exon 2) and, if negative, further analyzed for EGFR exon 20 insertions. All samples underwent extended genotyping for other driver mutations in EGFR, KRAS, BRAF, ERBB2/HER2, NRAS, PIK3CA, MEK1, and AKT by mass spectrometry; a subset was evaluated for ALK rearrangements. We identified 33 EGFR exon 20 insertion cases [2.2%, 95% confidence interval (CI), 1.6–3.1], all mutually exclusive with mutations in the other genes tested (except PIK3CA). They were more common among never-smokers (P < 0.0001). There was no association with age, sex, race, or stage. Morphologically, tumors were similar to those with common EGFR mutations but with frequent solid histology. Insertions were highly variable in position and size, ranging from 3 to 12 bp, resulting in 13 different insertions, which, by molecular modeling, are predicted to have potentially different effects on erlotinib binding. EGFR exon 20 insertion testing identifies a distinct subset of lung adenocarcinomas, accounting for at least 9% of all EGFR-mutated cases, representing the third most common type of EGFR mutation after exon 19 deletions and L858R. Insertions are structurally heterogeneous with potential implications for response to EGFR inhibitors. Mol Cancer Ther; 12(2); 220–9. ©2012 AACR.
A Human Single-Domain Antibody Elicits Potent Antitumor Activity by Targeting an Epitope in Mesothelin Close to the Cancer Cell Surface
Authors: Tang Zhewei , Feng Mingqian , Gao Wei , Phung Yen , Chen Weizao , Chaudhary Amit , Croix Brad St. , Qian Min , Dimitrov Dimiter S. , Ho Mitchell
Published: February 2013

Monoclonal antibodies against mesothelin are being evaluated for the treatment of mesothelioma and multiple forms of cancers, and show great promise for clinical development for solid cancers. Antibodies against mesothelin have been shown to act via immunotoxin-based inhibition of tumor growth and induction of antibody-dependent cell-mediated cytotoxicity (ADCC). However, complement-dependent cytotoxicity (CDC), considered an important additional mechanism of therapeutic antibodies against tumors, is inactive for such antibodies. Here, we used phage display antibody engineering technology and synthetic peptide screening to identify SD1, a human single-domain antibody to mesothelin. SD1 recognizes a conformational epitope at the C-terminal end (residues 539–588) of mesothelin close to the cell surface. To investigate SD1 as a potential therapeutic agent, we generated a recombinant human Fc (SD1-hFc) fusion protein. Interestingly, the SD1-hFc protein exhibits strong CDC activity, in addition to ADCC, against mesothelin-expressing tumor cells. Furthermore, it causes growth inhibition of human tumor xenografts in nude mice as a single agent. SD1 is the first human single-domain antibody targeting mesothelin-expressing tumors, shows potential as a cancer therapeutic candidate, and may improve current antibody therapy targeting mesothelin-expressing tumors. Mol Cancer Ther; 12(4); 416–26. ©2013 AACR.
Quantitative Chemical Proteomics Profiling Differentiates Erlotinib from Gefitinib inEGFRWild-Type Non–Small Cell Lung Carcinoma Cell Lines
Authors: Augustin Angélique , Lamerz Jens , Meistermann Hélène , Golling Sabrina , Scheiblich Stefan , Hermann Johannes C. , Duchateau-Nguyen Guillemette , Tzouros Manuel , Avila David W. , Langen Hanno , Essioux Laurent , Klughammer Barbara
Published: February 2013

Although both erlotinib and gefitinib target the EGF receptor (EGFR), erlotinib is effective in patients with EGFR wild-type or mutated tumors, whereas gefitinib is only beneficial for patients with activating mutations. To determine whether these differences in clinical outcomes can be attributed to their respective protein interaction profiles, a label-free, quantitative chemical proteomics study was conducted. Using this method, 24 proteins were highlighted in the binding profiles of erlotinib and gefitinib. Unlike gefinitib, erlotinib displaced the ternary complex formed by integrin-linked kinase (ILK), α-parvin, and PINCH (IPP). The docking of erlotinib in the three-dimensional structure of ILK showed that erlotinib has the ability to bind to the ATP-binding site, whereas gefitinib is unlikely to bind with high affinity. As the IPP complex has been shown to be involved in epithelial-to-mesenchymal transition (EMT) and erlotinib sensitivity has been correlated with EMT status, we used a cellular model of inducible transition and observed that erlotinib prevented EMT in a more efficient way than gefitinib by acting on E-cadherin expression as well as on IPP levels. A retrospective analysis of the MERIT trial indicated that, besides a high level of E-cadherin, a low level of ILK could be linked to clinical benefit with erlotinib. In conclusion, we propose that, in an EGFR wild-type context, erlotinib may have a complementary mode of action by inhibiting IPP complex activities, resulting in the slowing down of the metastatic process of epithelial tumors. Mol Cancer Ther; 12(4); 520–9. ©2013 AACR.
The Role of Platelet-Endothelial Cell Adhesion Molecule-1 in Atheroma Formation Varies Depending on the Site-Specific Hemodynamic Environment
Authors: Harrison Matthew , Smith Emily , Ross Ewan , Krams Robert , Segers Dolf , Buckley Christopher D. , Nash Gerard B. , Rainger G. Ed
Published: February 2013

Objective—

Polymorphisms in the platelet-endothelial cell adhesion molecule (PECAM-1)-1 gene are linked to increased risk of coronary artery disease. Because PECAM-1 has been demonstrated to form a mechanosensory complex that can modulate inflammatory responses in murine arterial endothelial cells, we hypothesized that PECAM-1 contributes to atherogenesis in a shear-dependent and site-specific manner.

Approach and Results—

ApoE
–/–
mice that were wild-type, heterozygous, or deficient in PECAM-1 were placed on a high-fat diet. Detailed analysis of the aorta at sites with differing hemodynamics revealed that PECAM-1–deficient mice had reduced disease in areas of disturbed flow, whereas plaque burden was increased in areas of steady, laminar flow. In concordance with these observations, bone marrow chimera experiments revealed that hematopoietic PECAM-1 resulted in accelerated atheroma formation in areas of laminar and disturbed flow, however endothelial PECAM-1 moderated disease progression in areas of high sheer stress. Moreover, using shear stress–modifying carotid cuffs, PECAM-1 was shown to promote macrophage recruitment into lesions developing in areas of low shear stress.

Conclusions—

PECAM-1 on bone marrow cells is proatherogenic irrespective of the hemodynamic environment, however endothelial cell PECAM-1 is antiatherogenic in high shear environments. Thus, targeting this pathway therapeutically would require a cell-type and context-specific strategy.
Genetic Determination of Plasma Cholesterol Efflux Capacity Is Gender-Specific and Independent of HDL-Cholesterol Levels
Authors: Villard Elise F. , EI Khoury Petra , Frisdal Eric , Bruckert Eric , Clement Karine , Bonnefont-Rousselot Dominique , Bittar Randa , Le Goff Wilfried , Guerin Maryse
Published: February 2013

Objective—

We investigated the impact of several genetic variants located in genes encoding for proteins involved in biogenesis, maturation, and intravascular remodeling of high density lipoprotein (HDL) particles on plasma efflux capacity.

Approach and Results—

The capacity of whole-plasma to mediate cholesterol efflux from cholesterol-loaded human THP-1 macrophages was measured in 846 individuals (450 men and 396 women). We demonstrated that rs17231506 (
CETP
c.–1337 C>T), rs2230806 (
ABCA1
p.R219K), rs1799837 (
APOA1
c.–75 G>A), rs5086 (
APOAII
c.–265 T>C), and rs1800588 (
LIPC
c.–514 C>T) single nucleotide polymorphisms (SNPs) significantly modulate the capacity of whole-plasma to mediate cholesterol efflux from human macrophages in a sex-dependent manner. Such associations were independent of circulating plasma lipid levels (HDL-cholesterol, triglyceride, low density lipoprotein-cholesterol). In women, we identified the
APOA1
c.–75 G>A and the
LIPC
c.–514 C>T variants as major contributors of interindividual variability of plasma efflux capacity, whereas the
ABCA1
p.R219K and the
APOAII
c.–265 T>C SNPs mostly contribute to total variance of plasma efflux capacity in men. Multiple regression analyses revealed that the 7 SNPs tested accounted together for approximately 6% of total plasma efflux capacity. We demonstrated that genetically determined plasma efflux capacity represents a better predictor of macrophage cholesterol removal, as compared with plasma HDL-cholesterol levels.

Conclusions—

Genetic variants located within genes encoding proteins involved in HDL metabolism significantly impact plasma efflux capacity independently of variation in plasma HDL-cholesterol levels.
Two-Dimensional Fluorescence In-Gel Electrophoresis of Coronary Restenosis Tissues in Minipigs
Authors: Lu Lin , Wang Ya Nan , Sun Wei Hua , Liu Zhu Hui , Zhang Qi , Pu Li Jin , Yang Ke , Wang Ling Jie , Zhu Zhen Bin , Meng Hua , Yang Ping , Du Run , Chen Qiu Jing , Wang Li Shun , Yu Hong , Shen Wei Feng
Published: February 2013

Objective—

We aimed to uncover the protein changes of coronary artery in-stent restenosis (ISR) tissue in minipigs with and without streptozotocin-induced diabetes mellitus by quantitative 2-dimensional fluorescence in-gel electrophoresis (2D-DIGE), and to investigate the influences of crucial proteins identified, particularly adipocyte fatty acid binding protein (AFABP), in human arterial smooth muscle cells.

Methods and Results—

Sirolimus-eluting stents were implanted in the coronary arteries of 15 diabetic and 26 nondiabetic minipigs, and angiography was repeated after 6 months. The intima tissue of significant ISR and non-ISR segments in both diabetic and nondiabetic minipigs was analyzed by 2D-DIGE and MALDI-TOF/TOF mass spectrometry. AFABP level was significantly increased in ISR tissue than in non-ISR tissue in both diabetic and nondiabetic minipigs, with level being higher in diabetic ISR than in nondiabetic ISR tissue. In human arterial smooth muscle cells, overexpression of AFABP significantly altered phenotype and promoted growth and migration, with effects more prominent in high-glucose than in low-glucose medium, whereas AFABP knockdown inhibited these effects. AFABP overexpression increased reactive oxygen species production by upregulating the expression of NADPH oxidase subunits Nox1, Nox4, and P22 through multiple pathways, with elevation of downstream gene cyclin D1, matrix metalloproteinase-2, and monocyte chemoattractant protein-1. However, AFABP-induced effects were inhibited by diphenyleneiodonium, pathway inhibitors, and small interfering RNA. In addition, the supernatant from AFABP-expressing human arterial smooth muscle cells and recombinant AFABP also promoted cellular growth and migration.

Conclusion—

This study has demonstrated that AFABP is significantly increased in coronary artery ISR segments of both diabetic and nondiabetic minipigs. Increased AFABP expression and secretory AFABP of human arterial smooth muscle cells promote growth and migration via reactive oxygen species-mediated activation.
New White Matter Brain Injury After Infant Heart Surgery Is Associated With Diagnostic Group and the Use of Circulatory Arrest
Authors: Beca John , Gunn Julia K. , Coleman Lee , Hope Ayton , Reed Peter W. , Hunt Rodney W. , Finucane Kirsten , Brizard Christian , Dance Brieana , Shekerdemian Lara S.
Published: February 2013

Background—

Abnormalities on magnetic resonance imaging scans are common both before and after surgery for congenital heart disease in early infancy. The aim of this study was to prospectively investigate the nature, timing, and consequences of brain injury on magnetic resonance imaging in a cohort of young infants undergoing surgery for congenital heart disease both with and without cardiopulmonary bypass.

Methods and Results—

A total of 153 infants undergoing surgery for congenital heart disease at <8 weeks of age underwent serial magnetic resonance imaging scans before and after surgery and at 3 months of age, as well as neurodevelopmental assessment at 2 years of age. White matter injury (WMI) was the commonest type of injury both before and after surgery. It occurred in 20% of infants before surgery and was associated with a less mature brain. New WMI after surgery was present in 44% of infants and at similar rates after surgery with or without cardiopulmonary bypass. The most important association was diagnostic group (
P
<0.001). In infants having arch reconstruction, the use and duration of circulatory arrest were significantly associated with new WMI. New WMI was also associated with the duration of cardiopulmonary bypass, postoperative lactate level, brain maturity, and WMI before surgery. Brain immaturity but not brain injury was associated with impaired neurodevelopment at 2 years of age.

Conclusions—

New WMI is common after surgery for congenital heart disease and occurs at the same rate in infants undergoing surgery with and without cardiopulmonary bypass. New WMI is associated with diagnostic group and, in infants undergoing arch surgery, the use of circulatory arrest.
Guidelines for the Early Management of Patients With Acute Ischemic Stroke
Authors: Jauch Edward C. , Saver Jeffrey L. , Adams Harold P. , Bruno Askiel , Connors J.J. (Buddy) , Demaerschalk Bart M. , Khatri Pooja , McMullan Paul W. , Qureshi Adnan I. , Rosenfield Kenneth , Scott Phillip A. , Summers Debbie R. , Wang David Z. , Wintermark Max , Yonas Howard
Published: February 2013

Background and Purpose—

The authors present an overview of the current evidence and management recommendations for evaluation and treatment of adults with acute ischemic stroke. The intended audiences are prehospital care providers, physicians, allied health professionals, and hospital administrators responsible for the care of acute ischemic stroke patients within the first 48 hours from stroke onset. These guidelines supersede the prior 2007 guidelines and 2009 updates.

Methods—

Members of the writing committee were appointed by the American Stroke Association Stroke Council’s Scientific Statement Oversight Committee, representing various areas of medical expertise. Strict adherence to the American Heart Association conflict of interest policy was maintained throughout the consensus process. Panel members were assigned topics relevant to their areas of expertise, reviewed the stroke literature with emphasis on publications since the prior guidelines, and drafted recommendations in accordance with the American Heart Association Stroke Council’s Level of Evidence grading algorithm.

Results—

The goal of these guidelines is to limit the morbidity and mortality associated with stroke. The guidelines support the overarching concept of stroke systems of care and detail aspects of stroke care from patient recognition; emergency medical services activation, transport, and triage; through the initial hours in the emergency department and stroke unit. The guideline discusses early stroke evaluation and general medical care, as well as ischemic stroke, specific interventions such as reperfusion strategies, and general physiological optimization for cerebral resuscitation.

Conclusions—

Because many of the recommendations are based on limited data, additional research on treatment of acute ischemic stroke remains urgently needed.
The Modified Graeb Score
Authors: Morgan Timothy C. , Dawson Jesse , Spengler Danielle , Lees Kennedy R. , Aldrich Chanel , Mishra Nishant K. , Lane Karen , Quinn Terence J. , Diener-West Marie , Weir Christopher J. , Higgins Peter , Rafferty Mark , Kinsley Katie , Ziai Wendy , Awad Issam , Walters Matthew R. , Hanley Daniel
Published: February 2013

Background and Purpose—

Simple and rapid measures of intraventricular hemorrhage (IVH) volume are lacking. We developed and validated a modification of the original Graeb scale to facilitate rapid assessment of IVH over time.

Methods—

We explored the relationship between the modified Graeb scale (mGS), original Graeb scale, measured IVH volume, and outcome using data from the Clot Lysis: Evaluating Accelerated Resolution of Hemorrhage with rtPA B (CLEAR B) study. We also explored its reliability. We then evaluated the relationship between mGS and outcome in a large sample of participants with IVH using data contained within the Virtual International Stroke Trials Archive (VISTA). We defined outcome using the modified Rankin scale (>3 signifying poor outcome).

Results—

The CLEAR B study included 360 scans from 36 subjects. The mGS score and IVH volume were highly correlated (R = 0.80,
P
<0.0001,
R
2
0.65). Baseline mGS was predictive of poor outcome (area under receiving operating characteristic curve 0.74, 95% confidence interval, 0.57–0.91), whereas the original Graeb scale was not. The VISTA study included 399 participants. Each unit increase in the mGS led to a 12% increase in the odds of a poor outcome (odds ratio, 1.12; 95% confidence interval, 1.05–1.19). Measures of reliability (intra- and inter- reader) were good in both studies.

Conclusions—

The mGS, a semiquantitative scale for IVH volume measurement, is a reliable measure with prognostic validity suitable for rapid use in clinical practice and in research.
Is Intracerebral Hemorrhage a Time-Dependent Phenomenon After Successful Combined Intravenous and Intra-Arterial Therapy?
Authors: Mosimann Pascal J. , Sirimarco Gaia , Meseguer Elena , Serfaty Jean-Michel , Laissy Jean-Pierre , Labreuche Julien , Lapergue Bertrand , Gonzalez-Valcarcel Jaime , Lavallée Philippa C. , Cabrejo Lucie , Guidoux Celine , Klein Isabelle F. , Olivot Jean-Marc , Schouman-Claeys Elisabeth , Amarenco Pierre , Mazighi Mikael
Published: February 2013

Background and Purpose—

Onset-to-reperfusion time (ORT) has recently emerged as an essential prognostic factor in acute ischemic stroke therapy. Although favorable outcome is associated with reduced ORT, it remains unclear whether intracranial bleeding depends on ORT. We therefore sought to determine whether ORT influenced the risk and volume of intracerebral hemorrhage (ICH) after combined intravenous and intra-arterial therapy.

Methods—

Based on our prospective registry, we included 157 consecutive acute ischemic stroke patients successfully recanalized with combined intravenous and intra-arterial therapy between April 2007 and October 2011. Primary outcome was any ICH within 24 hours posttreatment. Secondary outcomes included occurrence of symptomatic ICH (sICH) and ICH volume measured with the ABC/2.

Results—

Any ICH occurred in 26% of the study sample (n=33). sICH occurred in 5.5% (n=7). Median ICH volume was 0.8 mL. ORT was increased in patients with ICH (median=260 minutes; interquartile range=230–306) compared with patients without ICH (median=226 minutes; interquartile range=200–281;
P
=0.008). In the setting of sICH, ORT reached a median of 300 minutes (interquartile range=276–401;
P
=0.004). The difference remained significant after adjustment for potential confounding factors (adjusted
P
=0.045 for ICH; adjusted
P
=0.002 for sICH). There was no correlation between ICH volume and ORT (
r
=0.16;
P
=0.33).

Conclusions—

ORT influences the rate but not the volume of ICH and appears to be a critical predictor of symptomatic hemorrhage after successful combined intravenous and intra-arterial therapy. To minimize the risk of bleeding, revascularization should be achieved within 4.5 hours of stroke onset.
Norm-Establishing and Norm-Following in Autonomous Agency
Authors: Barandiaran Xabier E. , Egbert Matthew D.
Published: February 2013

Living agency is subject to a normative dimension (good-bad, adaptive-maladaptive) that is absent from other types of interaction. We review current and historical attempts to naturalize normativity from an organism-centered perspective, identifying two central problems and their solution: (1) How to define the topology of the viability space so as to include a sense of gradation that permits reversible failure, and (2) how to relate both the processes that establish norms and those that result in norm-following behavior. We present a minimal metabolic system that is coupled to a gradient-climbing chemotactic mechanism. Studying the relationship between metabolic dynamics and environmental resource conditions, we identify an emergent viable region and a precarious region where the system tends to die unless environmental conditions change. We introduce the concept of normative field as the change of environmental conditions required to bring the system back to its viable region. Norm-following, or normative action, is defined as the course of behavior whose effect is positively correlated with the normative field. We close with a discussion of the limitations and extensions of our model and some final reflections on the nature of norms and teleology in agency.
Staging the Self-Assembly Process: Inspiration from Biological Development
Authors: Bhalla Navneet , Bentley Peter J. , Vize Peter D. , Jacob Christian
Published: February 2013

One of the practical challenges facing the creation of self-assembling systems is being able to exploit a limited set of fixed components and their bonding mechanisms. The method of staging divides the self-assembly process into time intervals, during which components can be added to, or removed from, an environment at each interval. Staging addresses the challenge of using components that lack plasticity by encoding the construction of a target structure in the staging algorithm itself and not exclusively in the design of the components. Previous staging strategies do not consider the interplay between component physical features (morphological information). In this work we use morphological information to stage the self-assembly process, during which components can only be added to their environment at each time interval, to demonstrate our concept. Four experiments are presented, which use heterogeneous, passive, mechanical components that are fabricated using 3D printing. Two orbital shaking environments are used to provide energy to the components and to investigate the role of morphological information with component movement in either two or three spatial dimensions. The benefit of our staging strategy is shown by reducing assembly errors and exploiting bonding mechanisms with rotational properties. As well, a doglike target structure is used to demonstrate in theory how component information used at an earlier time interval can be reused at a later time interval, inspired by the use of a body plan in biological development. We propose that a staged body plan is one method toward scaling self-assembling systems with many interacting components. The experiments and body plan example demonstrate, as proof of concept, that staging enables the self-assembly of more complex morphologies not otherwise possible.
Analysis of Swarm Behaviors Based on an Inversion of the Fluctuation Theorem
Authors: Hamann Heiko , Schmickl Thomas , Crailsheim Karl
Published: February 2013

A grand challenge in the field of artificial life is to find a general theory of emergent self-organizing systems. In swarm systems most of the observed complexity is based on motion of simple entities. Similarly, statistical mechanics focuses on collective properties induced by the motion of many interacting particles. In this article we apply methods from statistical mechanics to swarm systems. We try to explain the emergent behavior of a simulated swarm by applying methods based on the fluctuation theorem. Empirical results indicate that swarms are able to produce negative entropy within an isolated subsystem due to frozen accidents. Individuals of a swarm are able to locally detect fluctuations of the global entropy measure and store them, if they are negative entropy productions. By accumulating these stored fluctuations over time the swarm as a whole is producing negative entropy and the system ends up in an ordered state. We claim that this indicates the existence of an inverted fluctuation theorem for emergent self-organizing dissipative systems. This approach bears the potential of general applicability.
Formalization, Implementation, and Modeling of Institutional Controllers for Distributed Robotic Systems
Authors: Pereira José N. , Silva Porfírio , Lima Pedro U. , Martinoli Alcherio
Published: February 2013

The work described is part of a long term program of introducing institutional robotics, a novel framework for the coordination of robot teams that stems from institutional economics concepts. Under the framework, institutions are cumulative sets of persistent artificial modifications made to the environment or to the internal mechanisms of a subset of agents, thought to be functional for the collective order. In this article we introduce a formal model of institutional controllers based on Petri nets. We define executable Petri nets—an extension of Petri nets that takes into account robot actions and sensing—to design, program, and execute institutional controllers. We use a generalized stochastic Petri net view of the robot team controlled by the institutional controllers to model and analyze the stochastic performance of the resulting distributed robotic system. The ability of our formalism to replicate results obtained using other approaches is assessed through realistic simulations of up to 40 e-puck robots. In particular, we model a robot swarm and its institutional controller with the goal of maintaining wireless connectivity, and successfully compare our model predictions and simulation results with previously reported results, obtained by using finite state automaton models and controllers.