bluuebunny/crossref_metadata_2025 huggingface dataset:
Lactate dilates cochlear capillaries via type V fibrocyte-vessel coupling signaled by nNOS
Authors: Dai Min , Yang Yue , Shi Xiaorui
Published: August 2011

Transduction of sound in the inner ear demands tight control over delivery of oxygen and glucose. However, the mechanisms underlying the control of regional blood flow are not yet fully understood. In this study, we report a novel local control mechanism that regulates cochlear blood flow to the stria vascularis, a high energy-consuming region of the inner ear. We found that extracellular lactate had a vasodilatory effect on the capillaries of the spiral ligament under both in vitro and in vivo conditions. The lactate, acting through monocarboxylate transporter 1 (MCT1), initiated neuronal nitric oxide (NO) synthase (nNOS) and catalyzed production of NO for the vasodilation. Blocking MCT1 with the MCT blocker, α-cyano-4-hydroxycinnamate (CHC), or a suppressing NO production with either the nonspecific inhibitor of NO synthase, NG-nitro-l-arginine methyl ester (l-NAME), or either of two selective nNOS inhibitors, 3-bromo-7-nitroindazole or (4S)- N-(4-amino-5[aminoethyl]aminopentyl)- N′-nitroguanidine (TFA), totally abolished the lactate-induced vasodilation. Pretreatment with the selective endothelial NO synthase inhibitor, l- N5-(1-iminoethyl)ornithine (l-NIO), eliminated the inhibition of lactate-induced vessel dilation. With immunohistochemical labeling, we found the expression of MCT1 and nNOS in capillary-coupled type V fibrocytes. The data suggest that type V fibrocytes are the source of the lactate-induced NO. Cochlear microvessel tone, regulated by lactate, is mediated by an NO-signaled coupling of fibrocytes and capillaries.
Maternal hypoxia alters matrix metalloproteinase expression patterns and causes cardiac remodeling in fetal and neonatal rats
Authors: Tong Wenni , Xue Qin , Li Yong , Zhang Lubo
Published: August 2011

Fetal hypoxia leads to progressive cardiac remodeling in rat offspring. The present study tested the hypothesis that maternal hypoxia results in reprogramming of matrix metalloproteinase (MMP) expression patterns and fibrillar collagen matrix in the developing heart. Pregnant rats were treated with normoxia or hypoxia (10.5% O2) from day 15 to 21 of gestation. Hearts were isolated from 21-day fetuses (E21) and postnatal day 7 pups (PD7). Maternal hypoxia caused a decrease in the body weight of both E21 and PD7. The heart-to-body weight ratio was increased in E21 but not in PD7. Left ventricular myocardium wall thickness and cardiomyocyte proliferation were significantly decreased in both fetal and neonatal hearts. Hypoxia had no effect on fibrillar collagen content in the fetal heart, but significantly increased the collagen content in the neonatal heart. Western blotting revealed that maternal hypoxia significantly increased collagen I, but not collagen III, levels in the neonatal heart. Maternal hypoxia decreased MMP-1 but increased MMP-13 and membrane type (MT)1-MMP in the fetal heart. In the neonatal heart, MMP-1 and MMP-13 were significantly increased. Active MMP-2 and MMP-9 levels and activities were not altered in either fetal or neonatal hearts. Hypoxia significantly increased tissue inhibitors of metalloproteinase (TIMP)-3 and TIMP-4 in both fetal and neonatal hearts. In contrast, TIMP-1 and TIMP-2 were not affected. The results demonstrate that in utero hypoxia reprograms the expression patterns of MMPs and TIMPs and causes cardiac tissue remodeling with the increased collagen deposition in the developing heart.
Alignment of sarcoplasmic reticulum-mitochondrial junctions with mitochondrial contact points
Authors: García-Pérez Cecília , Schneider Timothy G. , Hajnóczky György , Csordás György
Published: August 2011

Propagation of ryanodine receptor (RyR2)-derived Ca2+signals to the mitochondrial matrix supports oxidative ATP production or facilitates mitochondrial apoptosis in cardiac muscle. Ca2+transfer likely occurs locally at focal associations of the sarcoplasmic reticulum (SR) and mitochondria, which are secured by tethers. The outer mitochondrial membrane and inner mitochondrial membrane (OMM and IMM, respectively) also form tight focal contacts (contact points) that are enriched in voltage-dependent anion channels, the gates of OMM for Ca2+. Contact points could offer the shortest Ca2+transfer route to the matrix; however, their alignment with the SR-OMM associations remains unclear. Here, in rat heart we have studied the distribution of mitochondria-associated SR in submitochondrial membrane fractions and evaluated the colocalization of SR-OMM associations with contact points using transmission electron microscopy. In a sucrose gradient designed for OMM purification, biochemical assays revealed lighter fractions enriched in OMM only and heavier fractions containing OMM, IMM, and SR markers. Pure OMM fractions were enriched in mitofusin 2, an ∼80 kDa mitochondrial fusion protein and SR-mitochondrial tether candidate, whereas in fractions of OMM + IMM + SR, a lighter (∼50 kDa) band detected by antibodies raised against the NH2terminus of mitofusin 2 was dominating. Transmission electron microscopy revealed mandatory presence of contact points at the junctional SR-mitochondrial interface versus a random presence along matching SR-free OMM segments. For each SR-mitochondrial junction at least one tether was attached to contact points. These data establish the contact points as anchorage sites for the SR-mitochondrial physical coupling. Close coupling of the SR, OMM, and IMM is likely to provide a favorable spatial arrangement for local ryanodine receptor-mitochondrial Ca2+signaling.
Dihydrotestosterone attenuates hypoxia inducible factor-1α and cyclooxygenase-2 in cerebral arteries during hypoxia or hypoxia with glucose deprivation
Authors: Zuloaga Kristen L. , Gonzales Rayna J.
Published: August 2011

Dihydrotestosterone (DHT) attenuates cytokine-induced cyclooxygenase-2 (COX-2) in coronary vascular smooth muscle. Since hypoxia inducible factor-1α (HIF-1α) activation can lead to COX-2 production, this study determined the influence of DHT on HIF-1α and COX-2 following hypoxia or hypoxia with glucose deprivation (HGD) in the cerebral vasculature. COX-2 and HIF-1α levels were assessed via Western blot, and HIF-1α activation was indirectly measured via a DNA binding assay. Experiments were performed using cerebral arteries isolated from castrated male rats treated in vivo with placebo or DHT (18 days) followed by hypoxic exposure ex vivo (1% O2), cerebral arteries isolated from castrated male rats treated ex vivo with vehicle or DHT (10 or 100 nM; 18 h) and then exposed to hypoxia ex vivo (1% O2), or primary human brain vascular smooth muscle cells treated with DHT (10 nM; 6 h) or vehicle then exposed to hypoxia or HGD. Under normoxic conditions, DHT increased COX-2 (cells 51%; arteries ex vivo 31%; arteries in vivo 161%) but had no effect on HIF-1α. Following hypoxia or HGD, HIF-1α and COX-2 levels were increased; this response was blunted by DHT (cells HGD: −47% COX-2, −34% HIF-1α; cells hypoxia: −29% COX-2, −54% HIF-1α; arteries ex vivo: −37% COX-2; arteries in vivo: −35% COX-2) and not reversed by androgen receptor blockade. Hypoxia-induced HIF-1α DNA-binding was also attenuated by DHT (arteries ex vivo and in vivo: −55%). These results demonstrate that upregulation of COX-2 and HIF-1α in response to hypoxia is suppressed by DHT via an androgen receptor-independent mechanism.
NHE-1 participates in isoproterenol-induced downregulation of SERCA2a and development of cardiac remodeling in rat hearts
Authors: Shibata Munetaka , Takeshita Daisuke , Obata Koji , Mitsuyama Shinichi , Ito Haruo , Zhang Guo-Xing , Takaki Miyako
Published: August 2011

Impaired Ca2+ handling is one of the main characteristics in heart failure patients. Recently, we reported abnormal expressions of Ca2+-handling proteins in isoproterenol (ISO)-induced hypertrophied rat hearts. On the other hand, Na+/H+ exchanger (NHE)-1 inhibitor has been demonstrated to exert beneficial effects in ischemic-reperfusion injury and in the development of cardiac remodeling. The aims of the present study are to investigate the role of NHE-1 on Ca2+ handling and development of cardiac hypertrophy in ISO-infused rats. Male Wistar rats were randomly divided into vehicle [control (CTL)] and ISO groups without or with pretreatment with a selective NHE-1 inhibitor, BIIB-723. ISO infusion for 1 wk significantly increased the ratios of heart to body weight and left ventricle (LV) to body weight and collagen accumulation. All of these increases were antagonized by coadministration with BIIB-723. The ISO-induced significant increase in LV wall thickness was suppressed significantly ( P < 0.05) by BIIB-723. ISO-induced decreases in cardiac stroke volume and a total mechanical energy per beat index, systolic pressure-volume area at midrange LV volume, were normalized by BIIB-723. The markedly higher expression of NHE-1 protein in the ISO group than that in CTL group was suppressed ( P < 0.05) by BIIB-723. Surprisingly, ISO induced downregulation of the important Ca2+-handling protein sarcoplasmic reticulum Ca2+-ATPase 2a, the expression of which was also normalized by BIIB-723 without changes in phosphorylated phospholamban (PLB)/PLB expression. We conclude that NHE-1 contributes to ISO-induced abnormal Ca2+ handling associated with cardiac hypertrophy. Inhibition of NHE-1 ameliorates cardiac Ca2+-handling impairment and prevents the development of cardiac dysfunction in ISO-infused rats.
Reduced NO signaling during pregnancy attenuates outward uterine artery remodeling by altering MMP expression and collagen and elastin deposition
Authors: Hale Sarah A. , Weger Lindsey , Mandala Maurizio , Osol George
Published: August 2011

Recent findings indicate that endothelial nitric oxide (NO) plays a key role in uterine artery outward circumferential remodeling during pregnancy. Although the underlying mechanisms are not known, they likely involve matrix metalloproteinases (MMPs). The goal of this study was to examine the linkage among NO inhibition, expansive remodeling, and MMP expression within the uterine vascular wall. Adult female rats were treated with NG-nitro-l-arginine methyl ester [l-NAME (LPLN)] beginning on day 10 of pregnancy and until death at day 20 and compared with age-matched controls [late pregnant (LP)]. Mean arterial pressure of LPLN rats was significantly higher than controls. LPLN fetal and placental weights were significantly reduced compared with controls. Main uterine arteries (mUA) were collected to determine dimensional properties (lumen area and wall thickness), collagen and elastin content, and levels of endothelial nitric oxide synthase (eNOS) and MMP expression. Circumferential remodeling was attenuated, as evidenced by significantly smaller lumen diameters. eNOS RNA and protein were significantly (>90%) decreased in the LPLN mUA compared with LP. Collagen and elastin contents were significantly increased in LPLN rats by ∼10 and 25%, respectively, compared with LP ( P < 0.05). Both MMP-2 and tissue inhibitors of metalloproteinase-2 as assessed by immunofluorescence were lower in the endothelium (reduction of 60%) and adventitia (reduction of 50%) of LPLN compared with LP mUA. Membrane bound MMP-1 (MT1-MMP) as assessed by immunoblot was significantly decreased in LPLN. These data suggest a novel contribution of MMPs to gestational uterine vascular remodeling and substantiate the linkage between NO signaling and gestational remodeling of the uterine circulation via altered MMP, TIMP-2, and MT1-MMP expression and activity.
SIRT1-mediated acute cardioprotection
Authors: Nadtochiy Sergiy M. , Yao Hongwei , McBurney Michael W. , Gu Wei , Guarente Leonard , Rahman Irfan , Brookes Paul S.
Published: August 2011

Overexpression studies have revealed a role for silent information regulator of transcription 1 (SIRT1) lysine deacetylase in cardioprotection against ischemia-reperfusion injury via long-term transcriptional effects. However, short-term SIRT1-mediated lysine deacetylation, within the context of acute cardioprotection, is poorly understood. In this study, the role of SIRT1 in the acute cardioprotective paradigm of first window ischemic preconditioning (IPC) was studied using SIRT1-deficient (SIRT1+/−) and SIRT1-overexpressing (SIRT1+++) mice. In wild-type hearts, cytosolic lysine deacetylation was observed during IPC, and overacetylation was observed upon pharmacological SIRT1 inhibition. Consistent with a role for SIRT1 in IPC, SIRT1+/− hearts could not be preconditioned and exhibited increased cytosolic lysine acetylation. Furthermore, SIRT1+++ hearts were endogenously protected against ischemia-reperfusion injury and exhibited decreased cytosolic acetylation. Both of these effects in SIRT1+++ mice were reversed by pharmacological SIRT1 inhibition on an acute timescale. Several downstream targets of SIRT1 were examined, with data suggesting possible roles for endothelial nitric oxide synthase phosphorylation, NF-κB, and stimulation of autophagy. In conclusion, these data suggest that SIRT1, acting on nontranscriptional targets, is required for cardioprotection by acute IPC and that SIRT1-dependent lysine deacetylation occurs during IPC and may play a role in cardioprotective signaling.
Overexpression of type 1 angiotensin II receptors impairs excitation-contraction coupling in the mouse heart
Authors: Rivard Katy , Grandy Scott A. , Douillette Annie , Paradis Pierre , Nemer Mona , Allen Bruce G. , Fiset Céline
Published: August 2011

Transgenic mice that overexpress human type 1 angiotensin II receptor (AT1R) in the heart develop cardiac hypertrophy. Previously, we have shown that in 6-mo AT1R mice, which exhibit significant cardiac remodeling, fractional shortening is decreased. However, it is not clear whether altered contractility is attributable to AT1R overexpression or is secondary to cardiac hypertrophy/remodeling. Thus the present study characterized the effects of AT1R overexpression on ventricular L-type Ca2+ currents ( ICaL), cell shortening, and Ca2+ handling in 50-day and 6-mo-old male AT1R mice. Echocardiography showed there was no evidence of cardiac hypertrophy in 50-day AT1R mice but that fractional shortening was decreased. Cellular experiments showed that cell shortening, ICaL, and Cav1.2 mRNA expression were significantly reduced in 50-day and 6-mo-old AT1R mice compared with controls. In addition, Ca2+ transients and caffeine-induced Ca2+ transients were reduced whereas the time to 90% Ca2+ transient decay was prolonged in both age groups of AT1R mice. Western blot analysis revealed that sarcoplasmic reticulum Ca2+-ATPase and Na+/Ca2+ exchanger protein expression was significantly decreased in 50-day and 6-mo AT1R mice. Overall, the data show that cardiac contractility and the mechanisms that underlie excitation-contraction coupling are altered in AT1R mice. Furthermore, since the alterations in contractility occur before the development of cardiac hypertrophy, it is likely that these changes are attributable to the increased activity of the renin-angiotensin system brought about by AT1R overexpression. Thus it is possible that AT1R blockade may help maintain cardiac contractility in individuals with heart disease.
Hypertension from chronic central sodium chloride in mice is mediated by the ouabain-binding site on the Na,K-ATPase α2-isoform
Authors: Van Huysse James W. , Dostanic Iva , Lingrel Jerry B. , Hou Xiaohong , Wu Hengwei
Published: August 2011

A chronic increase in the concentration of sodium chloride in the cerebrospinal fluid (CSF) (↑CSF [NaCl]) appears to be critically important for the development of salt-dependent hypertension. In agreement with this concept, increasing CSF [NaCl] chronically by intracerebroventricular (icv) infusion of NaCl-rich artificial CSF (aCSF-HiNaCl) in rats produces hypertension by the same mechanisms (i.e., aldosterone-ouabain pathway in the brain) as that produced by dietary sodium in salt-sensitive strains. We first demonstrate here that icv aCSF-HiNaCl for 10 days also causes hypertension in wild-type (WT) mice. We then used both WT and gene-targeted mice to explore the mechanisms. In WT mice with a ouabain-sensitive Na,K-ATPase α2-isoform (α2S/S), mean arterial pressure rose by ∼25 mmHg within 2 days of starting aCSF-HiNaCl (0.6 nmol Na/min) and remained elevated throughout the study. Ouabain (171 pmol/day icv) increased blood pressure to a similar extent. aCSF-HiNaCl or ouabain given at the same rates subcutaneously instead of intracerebroventricularly had no effect on blood pressure. The pressor response to icv aCSF-HiNaCl was abolished by an anti-ouabain antibody given intracerebroventricularly but not subcutaneously, indicating that it is mediated by an endogenous ouabain-like substance in the brain. We compared the effects of icv aCSF-HiNaCl or icv ouabain on blood pressure in α2S/Sversus knockout/knockin mice with a ouabain-resistant endogenous α2-subunit (α2R/R). In α2R/R, there was no pressor response to icv aCSF-HiNaCl in contrast to WT mice. The α2R/Rgenotype also lacked a pressor response to icv ouabain. These data demonstrate that chronic ↑CSF [NaCl] causes hypertension in mice and that the blood pressure response is mediated by the ouabain-like substance in the brain, specifically by its binding to the α2-isoform of the Na,K-ATPase.
Toeplitz Operators on the Bergman Space of Planar Domains with Essentially Radial Symbols
Authors: Raimondo Roberto C.
Published: August 2011

We study the problem of the boundedness and compactness of Tϕ when ϕ ∈ L2(Ω) and Ω is a planar domain. We find a necessary and sufficient condition while imposing a condition that generalizes the notion of radial symbol on the disk. We also analyze the relationship between the boundary behavior of the Berezin transform and the compactness of Tϕ.
An Optimal Implementation on FPGA of a Hopfield Neural Network
Authors: Mansour W. , Ayoubi R. , Ziade H. , Velazco R. , EL Falou W.
Published: August 2011

The associative Hopfield memory is a form of recurrent Artificial Neural Network (ANN) that can be used in applications such as pattern recognition, noise removal, information retrieval, and combinatorial optimization problems. This paper presents the implementation of the Hopfield Neural Network (HNN) parallel architecture on a SRAM‐based FPGA. The main advantage of the proposed implementation is its high performance and cost effectiveness: it requires O(1) multiplications and O(log  N) additions, whereas most others require O(N) multiplications and O(N) additions.
Associations of Plasma Phospholipid Omega-6 and Omega-3 Polyunsaturated Fatty Acid Levels and MRI Measures of Cardiovascular Structure and Function: The Multiethnic Study of Atherosclerosis
Authors: Anderson Jennifer S. , Nettleton Jennifer A. , Hundley W. Gregory , Tsai Michael Y. , Steffen Lyn M. , Lemaitre Rozenn N. , Siscovick David , Lima João , Prince Martin R. , Herrington David
Published: August 2011

Background. The association between plasma omega-6 fatty acids and cardiovascular disease (CVD) is unclear, and discrepancy remains concerning the cardiovascular benefit of the omega-3 fatty acid alpha-linolenic acid.Methods. Associations of plasma phospholipid fatty acid levels (arachidonic acid, linoleic acid, eicosapentaenoic acid, docosahexaenoic acid (DHA), and alpha-linolenic acid) with cardiac magnetic resonance imaging measures of left ventricular (LV) mass, LV volume, ejection fraction, stroke volume, and aortic distensibility were investigated in 1,274 adults.Results. Results of multivariate analysis showed no statistically significant associations of plasma omega-6 or omega-3 levels with cardiac magnetic resonance imaging measures. Stratification by gender revealed a positive association between DHA and LV mass in women (β=1.89,P=0.02;Pinteraction = 0.003) and a trend for a positive association between DHA and ejection fraction in men (β=0.009,P=0.05;Pinteraction = 0.03).Conclusion. Additional research is warranted to clarify the effects of plasma DHA on cardiac structure and function in women versus men.
Fragmentation Pathways of Trifluoroacetyl Derivatives of Methamphetamine, Amphetamine, and Methylenedioxyphenylalkylamine Designer Drugs by Gas Chromatography/Mass Spectrometry
Authors: Kumazawa Takeshi , Hara Kenji , Hasegawa Chika , Uchigasaki Seisaku , Lee Xiao-Pen , Seno Hiroshi , Suzuki Osamu , Sato Keizo
Published: August 2011

Methamphetamine (MA), amphetamine (AM), and the methylenedioxyphenylalkylamine designer drugs, such as 3,4‐methylenedioxymethamphetamine (MDMA), 3,4‐methylenedioxyethylamphetamine (MDEA), N‐methyl‐1‐(3,4‐methylenedioxyphenyl)‐2‐butanamine (MBDB), 3,4‐methylenedioxyamphetamine (MDA), and 3,4‐(methylenedioxyphenyl)‐2‐butanamine (BDB), are widely abused as psychedelics. In this paper, these compounds were derivatized with trifluoroacetic (TFA) anhydride and analyzed by gas chromatography/mass spectrometry using electron ionization in positive mode. Gas chromatographic separation for TFA derivatives of all compounds was successfully resolved using an Equity‐5 fused silica capillary column with a poly (5% diphenyl‐95% dimethylsiloxane) stationary phase. Base peaks or prominent peaks of MA, AM, MDMA, MDEA, MBDB, MDA, and BDB appeared at m/z 154, 140, 154, 168, 168, 135, and 135, respectively. These occurred due to α‐cleavage from the amide nitrogen, splitting into the TFA imine species and benzyl or methylenedioxybenzyl cations. Further prominent fragment ions at m/z 118 for MA and AM, m/z 162 for MDMA, MDEA, and MDA, and m/z 176 for MBDB and BDB were produced by cleavage of the phenylpropane or methylenedioxypropane hydrocarbon radical cation via a hydrogen rearrangement. These fragmentation pathways for the TFA derivatives of all the compounds are summarized and illustrated in this paper.
High Molar Extinction Coefficient Ru(II)-Mixed Ligand Polypyridyl Complexes for Dye Sensitized Solar Cell Application
Authors: Chandrasekharam Malapaka , Rajkumar Ganugula , Rao Chikkam Srinivasa , Suresh Thogiti , Soujanya Yarasi , Reddy Paidi Yella
Published: August 2011

Two new ruthenium(II) mixed ligand terpyridine complexes, “Ru(Htcterpy)(NCS)(L1) (N(C4H9)4), mLBD1” and Ru(Htcterpy)(NCS)(L2)(N(C4H9)4), mLBD2 were synthesized and fully characterized by UV-Vis, emission, cyclic voltammogram, and other spectroscopic means, and the structures of the compounds are confirmed by 1H-NMR, ESI-MASS, and FT-IR spectroscopes. The influence of the substitution of L1 and L2 on solar-to-electrical energy conversion efficiency (η) of dye-sensitized solar cells (DSSCs) was evaluated relative to reference black dye. The dyes showed molar extinction coefficients of 17600 M−1 cm−1 for mLBD1 and 21300 M−1 cm−1 for mLBD2 both at λ maximum of 512 nm, while black dye has shown 8660 M−1 cm−1 at λ maximum of 615 nm. The monochromatic incident photon-to-collected electron conversion efficiencies of 60.71% and 75.89% were obtained for mLBD1 and mLBD2 dyes, respectively. The energy conversion efficiencies of mLBD1 and mLBD2 dyes are 3.15% ( mA/cm2,  mV, ) and 3.36% ( mA/cm2,  mV, ), respectively, measured at the AM1.5G conditions, the reference black dye-sensitized solar cell, fabricated and evaluated under identical conditions exhibited η-value of 2.69% ( mA/cm2,  mV, ).
Ecological Divergence and the Origins of Intrinsic Postmating Isolation with Gene Flow
Authors: Agrawal Aneil F. , Feder Jeffrey L. , Nosil Patrik
Published: August 2011

The evolution of intrinsic postmating isolation has received much attention, both historically and in recent studies of speciation genes. Intrinsic isolation often stems from between-locus genetic incompatibilities, where alleles that function well within species are incompatible with one another when brought together in the genome of a hybrid. It can be difficult for such incompatibilities to originate when populations diverge with gene flow, because deleterious genotypic combinations will be created and then purged by selection. However, it has been argued that if genes underlying incompatibilities are themselves subject to divergent selection, then they might overcome gene flow to diverge between populations, resulting in the origin of incompatibilities. Nonetheless, there has been little explicit mathematical exploration of such scenarios for the origin of intrinsic incompatibilities during ecological speciation with gene flow. Here we explore theoretical models for the origin of intrinsic isolation where genes subject to divergent natural selection also affect intrinsic isolation, either directly or via linkage disequilibrium with other loci. Such genes indeed overcome gene flow, diverge between populations, and thus result in the evolution of intrinsic isolation. We also examine barriers to neutral gene flow. Surprisingly, we find that intrinsic isolation sometimes weakens this barrier, by impeding differentiation via ecologically based divergent selection.
In Situ IR Characterization of CO Interacting with Rh Nanoparticles Obtained by Calcination and Reduction of Hydrotalcite‐Type Precursors
Authors: Basile F. , Bersani I. , Del Gallo P. , Fiorilli S. , Fornasari G. , Gary D. , Mortera R. , Onida B. , Vaccari A.
Published: August 2011

Supported Rh nanoparticles obtained by reduction in hydrogen of severely calcined Rh/Mg/Al hydrotalcite‐type (HT) phases have been characterized by FT‐IR spectroscopy of adsorbed CO [both at room temperature (r.t.) and nominal liquid nitrogen temperature] and Transmission Electron Microscopy (TEM). The effect of reducing temperature has been investigated, showing that Rh crystal size increases from 1.4 nm to 1.8 nm when the reduction temperature increases from 750°C to 950°C. The crystal growth favours the formation of bridged CO species and linear monocarbonyl species with respect to gem‐dicarbonyl species; when CO adsorbs at r.t., CO disproportionation occurs on Rh and it accompanies the formation of RhI(CO)2. The role of interlayer anions in the HT precursors to affect the properties of the final materials has been also investigated considering samples prepared from silicate‐instead of carbonate‐containing precursors. In this case, formation of RhI(CO)2 and CO disproportionation do not occur, and this evidence is discussed in terms of support effect.
Seismic Performance Comparison of a High-Content SDA Frame and Standard RC Frame
Authors: van de Lindt John W. , Rechan R. Karthik
Published: August 2011

This study presents the method and results of an experiment to study the seismic behavior of a concrete portal frame with fifty percent of its cement content replaced with a spray dryer ash (SDA). Based on multiple-shake-table tests, the high content SDA frame was found to perform as well as the standard concrete frame for two earthquakes exceeding design-level intensity earthquakes. Hence, from a purely seismic/structural standpoint, it may be possible to replace approximately fifty percent of cement in a concrete mix with SDA for the construction of structural members in high seismic zones. This would help significantly redirect spray dryer ash away from landfills, thus, providing a sustainable greener alternative to concrete that uses only Portland cement, or only a small percentage of SDA or fly ash.
Diagnosis and Management of Cystic Lesions of the Pancreas
Authors: Jani Niraj , Bani Hani Murad , Schulick Richard D. , Hruban Ralph H. , Cunningham Steven C.
Published: August 2011

Pancreatic cysts are challenging lesions to diagnose and to treat. Determining which of the five most common diagnoses—pancreatic pseudocyst, serous cystic neoplasm (SCN), solid pseudopapillary neoplasm (SPN), mucinous cystic neoplasm (MCN), and intraductal mucinous papillary neoplasm (IPMN)—is likely the correct one requires the careful integration of many historical, radiographic, laboratory, and other factors, and management is markedly different depending on the type of cystic lesion of the pancreas. Pseudocysts are generally distinguishable based on historical, clinical and radiographic characteristics, and among the others, the most important differentiation is between the mucin-producing MCN and IPMN (high risk for cancer) versus the serous SCN and SPN (low risk for cancer). EUS with FNA and cyst-fluid analysis will continue to play an important role in diagnosis. Among mucinous lesions, those that require treatment (resection currently) are any MCN, any MD IPMN, and BD IPMN larger than 3 cm, symptomatic, or with an associated mass, with the understanding that SCN or pseudocysts may be removed inadvertently due to diagnostic inaccuracy, and that a certain proportion of SPN will indeed be malignant at the time of removal. The role of ethanol ablation is under investigation as an alternative to resection in selected patients.
Rupture of the Distal Biceps Tendon Combined with a Supinator Muscle Tear in a 51-Year-Old Woman: A Case Report
Authors: Nayyar Samir , Quirno Martin , Hasan Saqib , Rybak Leon , Meislin Robert J.
Published: August 2011

Distal biceps tendon rupture is a relatively uncommon occurrence in the general female population, and to our knowledge, has not been reported in association with a supinator muscle tear. We report a case of 51-year-old woman who experienced sharp pain in her forearm and elbow after lifting a heavy object. History and physical examination raised suspicion for a distal biceps tendon rupture. MRI imaging determined a combined distal biceps tendon tear with a supinator muscle tear with subsequent confirmation at surgery. Surgical repair was performed for the distal biceps tendon only through a single incision approach using the Endobutton technique.
Moderate Weight Reduction in an Outpatient Obesity Intervention Program Significantly Reduces Insulin Resistance and Risk Factors for Cardiovascular Disease in Severely Obese Adolescents
Authors: Grulich-Henn J. , Lichtenstein S. , Hörster F. , Hoffmann G. F. , Nawroth P. P. , Hamann A.
Published: August 2011

Background. Metabolic risk factors like insulin resistance and dyslipidemia are frequently observed in severly obese children. We investigated the hypothesis that moderate weight reduction by a low-threshold intervention is already able to reduce insulin resistance and cardiovascular risk factors in severely obese children.Methods. A group of 58 severely obese children and adolescents between 8 and 17 years participating in a six-month-long outpatient program was studied before and after treatment. The program included behavioral treatment, dietary education and specific physical training. Metabolic parameters were measured in the fasting state, insulin resistance was evaluated in an oral glucose tolerance test.Results. Mean standard deviation score of the body mass index (SDS-BMI) in the study group dropped significantly from +2.5 ± 0.5 to 2.3 ± 0.6 (P<0.0001) after participation in the program. A significant decrease was observed in HOMA (6.3 ± 4.2 versus 4.9 ± 2.4,P<0.03, and in peak insulin levels (232.7 ± 132.4 versus 179.2 ± 73.3 μU/mL,P<0.006). Significant reductions were also observed in mean levels of hemoglobin A1c, total cholesterol and LDL cholesterol.Conclusions. These data demonstrate that already moderate weight reduction is able to decrease insulin resistance and dyslipidemia in severely obese children and adolescents.
The Construction of Chimeric T‐Cell Receptor with Spacer Base of Modeling Study of VHH and MUC1 Interaction
Authors: Pirooznia Nazanin , Hasannia Sadegh , Taghdir Majid , Rahbarizadeh Fatemeh , Eskandani Morteza
Published: August 2011

Adaptive cell immunotherapy with the use of chimeric receptors leads to the best and most specific response against tumors. Chimeric receptors consist of a signaling fragment, extracellular spacer, costimulating domain, and an antibody. Antibodies cause immunogenicity; therefore, VHH is a good replacement for ScFv in chimeric receptors. Since peptide sequences have an influence on chimeric receptors, the effect of peptide domains on each other′s conformation were investigated. CD3Zeta, CD28, VHH and CD8α, and FcgIIα are used as signaling moieties, costimulating domain, antibody, and spacers, respectively. To investigate the influence of the ligation of spacers on the conformational structure of VHH, models of VHH were constructed. Molecular dynamics simulation was run to study the influence of the presence of spacers on the conformational changes in the binding sites of VHH. Root mean square deviation and root mean square fluctuation of critical segments in the binding site showed no noticeable differences with those in the native VHH. Results from molecular docking revealed that the presence of spacer FcgIIα causes an increasing effect on VHH with MUC1 interaction. Each of the constructs was transformed into the Jurkat E6.1. Expression analysis and evaluation of their functions were examined. The results showed good expression and function.
Calculation of the Effective Delayed Neutron Fraction by Deterministic and Monte Carlo Methods
Authors: Carta M. , Dulla S. , Peluso V. , Ravetto P. , Bianchini G.
Published: August 2011

The studies on Accelerator‐Driven Systems (ADSs) have renewed the interest in the theoretical and computational evaluation of the main integral parameters characterizing subcritical systems (e.g., reactivity, effective delayed neutron fraction βeff, and mean prompt neutron generation time). In particular, some kinetic parameters, as the effective delayed neutron fraction, are evaluated in Monte Carlo codes by formulations which do not require the calculation of the adjoint flux. This paper is focused on a theoretical and computational analysis about how the different βeff definitions are connected and which are the approximations inherent to the Monte Carlo definition with respect to the standard definition involving weighted integrals. By means of a refined transport computational analysis carried out in a coherent and consistent way, that is, using the same deterministic code and neutron data library for the βeff evaluation in different ways, the theoretical analysis is numerically confirmed. Both theoretical and numerical results confirm the effectiveness of the Monte Carlo βeff evaluation, at least in cases where spectral differences between total and prompt fluxes are negligible with respect to the value of the functionals entering the classical βeff formulation.
Does “Yummy” Food Help You Grow and Avoid Illness? Children's and Adults' Understanding of the Effect of Psychobiological Labels on Growth and Illness
Authors: Raman Lakshmi
Published: August 2011

Three studies examined children's understanding of the role of psychobiological labels such as tasty (“yummy”) and not tasty (“yucky”) foods on growth and illness. Studies 1 and 3 examined the role of tasty and not tasty foods on height, weight, and illness, respectively. Study 2 controlled for the possibility that participants were responding to the positive and negative valence of the terms “yummy” and “yucky” in Study 1. Results revealed that young children entertain psychobiological causes for growth but not for illness. These results suggest that young children selectively apply psychobiological causes to explain different biological processes.
Familial Renal Cancer: Molecular Genetics and Surgical Management
Authors: Barrisford Glen W. , Singer Eric A. , Rosner Inger L. , Linehan W. Marston , Bratslavsky Gennady
Published: August 2011

Familial renal cancer (FRC) is a heterogeneous disorder comprised of a variety of subtypes. Each subtype is known to have unique histologic features, genetic alterations, and response to therapy. Through the study of families affected by hereditary forms of kidney cancer, insights into the genetic basis of this disease have been identified. This has resulted in the elucidation of a number of kidney cancer gene pathways. Study of these pathways has led to the development of novel targeted molecular treatments for patients affected by systemic disease. As a result, the treatments for families affected by von Hippel-Lindau (VHL), hereditary papillary renal carcinoma (HPRC), hereditary leiomyomatosis renal cell carcinoma (HLRCC), and Birt-Hogg-Dubé (BHD) are rapidly changing. We review the genetics and contemporary surgical management of familial forms of kidney cancer.
Nearly Supersymmetric Dark Atoms
Authors: Behbahani Siavosh R. , Jankowiak Martin , Rube Tomas , Wacker Jay G.
Published: August 2011

Theories of dark matter that support bound states are an intriguing possibility for the identity of the missing mass of the Universe. This article proposes a class of models of supersymmetric composite dark matter where the interactions with the Standard Model communicate supersymmetry breaking to the dark sector. In these models, supersymmetry breaking can be treated as a perturbation on the spectrum of bound states. Using a general formalism, the spectrum with leading supersymmetry effects is computed without specifying the details of the binding dynamics. The interactions of the composite states with the Standard Model are computed, and several benchmark models are described. General features of nonrelativistic supersymmetric bound states are emphasized.
Collective Dynamics of Swarms with a New Attraction/Repulsion Function
Authors: Shi Hong , Xie Guangming
Published: August 2011

We specify an “individual‐based” continuous‐time model for swarm aggregation in n‐dimensional Euclidean space. We show that the swarm is completely stable, and the center of the swarm is stationary. Numerical simulations indicate that the individuals will form a stable and cohesive swarm, and under the attraction/repulsion function, the bound of the swarm size will increase as the number of individuals increases.
Synchronization and Antisynchronization of a Planar Oscillation of Satellite in an Elliptic Orbit via Active Control
Authors: Shahzad Mohammad
Published: August 2011

We have investigated the synchronization and antisynchronization behaviour of two identical planar oscillation of a satellite in elliptic orbit evolving from different initial conditions using the active control technique based on the Lyapunov stability theory and the Routh‐Hurwitz criteria. The designed controller, with our own choice of the coefficient matrix of the error dynamics that satisfy the Lyapunov stability theory and the Routh‐Hurwitz criteria, is found to be effective in the stabilization of the error states at the origin, thereby, achieving synchronization and antisynchronization between the states variables of two nonlinear dynamical systems under consideration. The results are validated by numerical simulations using mathematica.
A Review of Tilting Pad Bearing Theory
Authors: Dimond Timothy , Younan Amir , Allaire Paul
Published: August 2011

A theoretical basis for static and dynamic operation of tilting pad journal bearings (TPJBs) has evolved over the last 50 years. Originally demonstrated by Lund using the pad assembly method and a classic Reynolds equation solution, the current state of the art includes full thermoelastohydrodynamic solutions of the generalized Reynolds equation that include fluid convective inertia effects, pad motions; and thermal and mechanical deformations of the pads and shaft. The development of TPJB theory is reviewed, emphasizing dynamic modeling. The paper begins with the early analyses of fixed geometry bearings and continues to modern analyses that include pad motion and stiffness and damping effects. The development of thermohydrodynamic, thermoelastohydrodynamic, and bulk-flow analyses is reviewed. The theories of TPJB dynamics, including synchronous and nonsynchronous models, are reviewed. A discussion of temporal inertia effects in tilting pad bearing is considered. Future trends are discussed, and a path for experimental verification is proposed.
Comparative Statics of Central Bank Liquidity Management: Some Insights
Authors: Bhattacharyya Indranil , Sahoo Satyananda
Published: August 2011

The paper demonstrates the efficacy of liquidity management through both the rate and quantum channels. Using the concepts of autonomous and discretionary liquidity, the paper derives the optimal policy mix of instruments which can be used for stabilizing the price of liquidity. For effective liquidity management, the sufficient condition highlighted in the paper has important implications for developing market‐related monetary policy instruments, particularly in emerging market economies.
Nanocarriers for Nitric Oxide Delivery
Authors: Saraiva Juliana , Marotta-Oliveira Samantha S. , Cicillini Simone Aparecida , Eloy Josimar de Oliveira , Marchetti Juliana Maldonado
Published: August 2011

Nitric oxide (NO) is a promising pharmaceutical agent that has vasodilative, antibacterial, and tumoricidal effects. To study the complex and wide-ranging roles of NO and to facilitate its therapeutic use, a great number of synthetic compounds (e.g., nitrosothiols, nitrosohydroxyamines, N-diazeniumdiolates, and nitrosyl metal complexes) have been developed to chemically stabilize and release NO in a controlled manner. Although NO is currently being exploited in many biomedical applications, its use is limited by several factors, including a short half-life, instability during storage, and potential toxicity. Additionally, efficient methods of both localized and systemicin vivodelivery and dose control are needed. One strategy for addressing these limitations and thus increasing the utility of NO donors is based on nanotechnology.
A Cohort Study of p53 Mutations and Protein Accumulation in Benign Breast Tissue and Subsequent Breast Cancer Risk
Authors: Kabat Geoffrey C. , Kandel Rita A. , Glass Andrew G. , Jones Joan G. , Olson Neal , Duggan Catherine , Ginsberg Mindy , Negassa Abdissa , Rohan Thomas E.
Published: August 2011

Mutations in the p53 tumor suppressor gene and accumulation of its protein in breast tissue are thought to play a role in breast carcinogenesis. However, few studies have prospectively investigated the association of p53 immunopositivity and/or p53 alterations in women with benign breast disease in relation to the subsequent risk of invasive breast cancer. We carried out a case-control study nested within a large cohort of women biopsied for benign breast disease in order to address this question. After exclusions, 491 breast cancer cases and 471 controls were available for analysis. Unconditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (95% CI). Neither p53 immunopositivity nor genetic alterations in p53 (either missense mutations or polymorphisms) was associated with altered risk of subsequent breast cancer. However, the combination of both p53 immunopositivity and any p53 nucleotide change was associated with an approximate 5-fold nonsignificant increase in risk (adjusted OR 4.79, 95% CI 0.28–82.31) but the confidence intervals were extremely wide. Our findings raise the possibility that the combination of p53 protein accumulation and the presence of genetic alterations may identify a group at increased risk of breast cancer.
Hypertriglyceridemia, Metabolic Syndrome, and Cardiovascular Disease in HIV-Infected Patients: Effects of Antiretroviral Therapy and Adipose Tissue Distribution
Authors: van Wijk Jeroen P. H. , Cabezas Manuel Castro
Published: August 2011

The use of combination antiretroviral therapy (CART) in HIV-infected patients has resulted in a dramatic decline in AIDS-related mortality. However, mortality due to non-AIDS conditions, particularly cardiovascular disease (CVD) seems to increase in this population. CART has been associated with several metabolic risk factors, including insulin resistance, low HDL-cholesterol, hypertriglyceridemia and postprandial hyperlipidemia. In addition, HIV itself, as well as specific antiretroviral agents, may further increase cardiovascular risk by interfering with endothelial function. As the HIV population is aging, CVD may become an increasingly growing health problem in the future. Therefore, early diagnosis and treatment of cardiovascular risk factors is warranted in this population. This paper reviews the contribution of both, HIV infection and CART, to insulin resistance, postprandial hyperlipidemia and cardiovascular risk in HIV-infected patients. Strategies to reduce cardiovascular risk are also discussed.
Adipokines as Possible New Predictors of Cardiovascular Diseases: A Case Control Study
Authors: Pala Laura , Monami Matteo , Ciani Silvia , Dicembrini Ilaria , Pasqua Alessandro , Pezzatini Anna , Francesconi Paolo , Cresci Barbara , Mannucci Edoardo , Rotella Carlo Maria
Published: August 2011

Background and Aims. The secretion of several adipocytokines, such as adiponectin, retinol-binding protein 4 (RBP4), adipocyte fatty acid binding protein (aFABP), and visfatin, is altered in subjects with abdominal adiposity; these endocrine alterations could contribute to increased cardiovascular risk. The aim of the study was to assess the relationship among adiponectin, RBP4, aFABP, and visfatin, and incident cardiovascular disease.Methods and Results. A case-control study, nested within a prospective cohort, on 2945 subjects enrolled for a diabetes screening program was performed. We studied 18 patients with incident fatal or nonfatal IHD (Ischemic Heart Disease) or CVD (Cerebrovascular Disease), compared with 18 matched control subjects. Circulating adiponectin levels were significantly lower in cases of IHD with respect to controls. Circulating RBP4 levels were significantly increased in CVD and decreased in IHD with respect to controls. Circulating aFABP4 levels were significantly increased in CVD, while no difference was associated with IHD. Circulating visfatin levels were significantly lower in cases of both CVD and IHD with respect to controls, while no difference was associated with CVD.Conclusions. The present study confirms that low adiponectin is associated with increased incidents of IHD, but not CVD, and suggests, for the first time, a major effect of visfatin, aFABP, and RBP4 in the development of cardiovascular disease.
Chinese Herbal Formula Xiao Yao San for Treatment of Depression: A Systematic Review of Randomized Controlled Trials
Authors: Zhang Yuqing , Han Mei , Liu Zhijun , Wang Jie , He Qingyong , Liu Jianping
Published: August 2011

Objectives.To assess the beneficial and adverse effects of Xiaoyaosan for depression.Search Strategy. Electronic databases were searched until December 2009.Inclusion Criteria.We included randomized clinical trials testing Xiaoyaosan against placebo, antidepressants, or combined with antidepressants against antidepressants alone.Data Extraction and Analyses.Study selection, data extraction, quality assessment, and data analyses were conducted according to the Cochrane standards.Results.26 randomized trials (involving 1837 patients) were included and the methodological quality was evaluated as generally low. The pooled results showed that Xiaoyaosan combined with antidepressants was more effective in comprehensive effect, the score of HAMD and the score of SDS compared with antidepressants alone. Xiaoyaosan was superior to antidepressants for the score of HAMD. However, Xiaoyaosan was not different from placebo for the score of SDS. There was no adverse effects reported in the trials from Xiaoyaosan.Conclusions.Xiaoyaosan appears to be effective on improving symptoms in patients with depression. However, due to poor methodological quality in the majority of included trials, the potential benefit from Xiaoyaosan need to be confirmed in rigorous trials and the design and reporting of trials should follow international standards.
Circulation
Editors' Picks II
Authors:   The Editors
Published: August 2011

The following articles are being highlighted as part of
Circulation's
Topic Review series. This series will summarize the most important manuscripts, as selected by the editors, published in
Circulation
and the
Circulation
subspecialty journals. The studies included in this article represent the Editors' Picks for each
Circulation
issue published in 2010.