bluuebunny/crossref_metadata_2025 huggingface dataset:
A Change in the Geodynamics of Continental Growth 3 Billion Years Ago
Authors: Dhuime Bruno , Hawkesworth Chris J. , Cawood Peter A. , Storey Craig D.
Published: March 2012

Continental Growth Spurts

The appearance and persistence of continents through geologic time has influenced most processes on Earth, from the evolution of new species to the climate. The relative proportion of newly formed crust compared to reworked, or destroyed, older crust reveals which processes controlled continental growth. Based on the combined analyses of Hf-Pb and O isotopes in zircon minerals,

Dhuime
et al.

(p.
1334
) measured continuous but variable rates of new crustal production throughout Earth's history. Increased rates of crustal destruction starting around 3 billion years ago coincide with the onset of subduction-drive plate tectonics, slowing down the overall rate of crustal growth.
Structural Basis for the Rescue of Stalled Ribosomes: Structure of YaeJ Bound to the Ribosome
Authors: Gagnon Matthieu G. , Seetharaman Sai V. , Bulkley David , Steitz Thomas A.
Published: March 2012

Ribosome Rescue

Ribosomes stall when they reach the end of defective messenger RNAs (mRNAs). In bacteria, the most-studied ribosomal rescue pathway involves a ribonucleoprotein complex comprising tmRNA (which acts as both transfer RNA and mRNA) and the protein SmpB. In an alternative pathway, some Gram-negative bacteria contain proteins that achieve tmRNA-independent rescue. Now,

Neubauer
et al.

(p.
1366
) present the structure of the
Thermus thermophilus
ribosome bound to a fragment of tmRNA, SmpB, and elongation factor Tu, and

Gagnon
et al.

(p.
1370
) report the structure of the
T. thermophilus
ribosome in complex with an initiator tRNA, a short mRNA fragment, and the rescue factor YaeJ. Though the two rescue systems are very different, both involve a protein tail that binds in the mRNA channel. This orients the rescue apparatus to facilitate switching translation to a different message in the tmRNA system or hydrolysis of peptidyl tRNA by YaeJ.
Monitoring Volcanoes
Authors: Sparks R. S. J. , Biggs J. , Neuberg J. W.
Published: March 2012

Despite technological advances, volcano monitoring around the world is woefully incomplete.
HIV Prevention and Cure Insights Come From Failure and Success
Authors: Cohen Jon
Published: March 2012

At last week's 19th Conference on Retroviruses and Opportunistic Infections , research on ways to cure HIV infections received more attention than ever.
Heart-Stopping Revelation About How Chinese Mushroom Kills
Authors: Stone Richard
Published: March 2012

Researchers have isolated the toxins of the mushroom behind Yunnan sudden unexplained death and propose an astonishing modus operandi.
Validation of the MycAssay Pneumocystis Kit for Detection of Pneumocystis jirovecii in Bronchoalveolar Lavage Specimens by Comparison to a Laboratory Standard of Direct Immunofluorescence Microscopy, Real-Time PCR, or Conventional PCR
Authors: McTaggart Lisa R. , Wengenack Nancy L. , Richardson Susan E.
Published: March 2012

Pneumocystis jirovecii
pneumonia is a significant cause of morbidity and mortality in AIDS patients as well as those with non-HIV immunosuppressive diseases. To aid diagnosis, the commercial MycAssay
Pneumocystis
real-time PCR assay (Myconostica, Ltd., Manchester, United Kingdom) targeting the mitochondrial ribosomal large subunit (mtLSU) has been developed to detect
P. jirovecii
in bronchoalveolar lavage (BAL) specimens. Here, we validated this assay against a laboratory standard of direct immunofluorescence microscopy, a
cdc2
real-time PCR assay, or conventional PCR and sequencing of mtLSU. While more sensitive than any of these three assays analyzed individually, the MycAssay
Pneumocystis
assay demonstrated 100% sensitivity, 100% specificity, a 100% negative predictive value, and a 100% positive predictive value for detecting the presence of
P. jirovecii
in BAL specimens compared to the laboratory standard. Of note, two samples with positive cycle threshold (

C
T

) values according to the MycAssay
Pneumocystis
assay lacked exponential amplification curves and thus were deemed negative. Also negative according to the laboratory standard, these samples highlight the importance of examining the amplification curves, in addition to noting the

C
T

values, when interpreting positive results. Comparison of the MycAssay
Pneumocystis
assay to a laboratory standard establishes this assay to be a highly sensitive and specific method for the detection of
P. jirovecii
in bronchoalveolar lavage specimens. The approach may also be useful for the clinical laboratory validation of other sensitive real-time PCR assays.
Mechanisms of reducing postoperative pain, nausea and vomiting: a systematic review of current techniques
Authors: Rawlinson Alex , Kitchingham Nina , Hart Colin , McMahon Gregory , Ong Seok Ling , Khanna Achal
Published: March 2012

Background

Multimodal recovery programmes decrease hospital stay. The objective of this systematic review was to assess how single-modality evidence-based care principles, regarding postoperative analgesia and postoperative nausea and vomiting (PONV) prophylaxis, combine to achieve this.

Methods

A systematic review of randomised controlled trials was performed. Relevant trials compared postoperative epidural analgesia/parenteral opioid analgesia/paracetamol/non-steroidal anti-inflammatory drugs (NSAIDs) and postoperative antiemetics. The effect on recovery was evaluated in terms of length of hospital stay, pain intensity, duration of gastrointestinal dysfunction and incidence of PONV.

Results

Twenty-three trials were included. Epidural anaesthesia failed to reduce length of stay or the incidence of PONV when compared to controls. Pain intensity and time to first bowel movement were reduced (p<0.05). Paracetamol did not reduce the incidence of PONV. NSAIDs reduced postoperative opioid consumption and the incidence of PONV (p<0.05). Dexamethasone and 5-HT3 antagonists reduced the incidence of PONV compared to controls.

Conclusions

Epidural anaesthesia appears to not reduce length of hospital stay or incidence of PONV despite reducing pain intensity and ileus. NSAIDs are more effective than paracetamol in reducing postoperative opioid consumption and PONV, while dexamethasone and 5-HT3 antagonists are both effective in reducing PONV.
Softening the Complexity of Entropic Motion on Curved Statistical Manifolds
Authors: Cafaro Carlo , Giffin Adom , Lupo Cosmo , Mancini Stefano
Published: March 2012

We study the information geometry and the entropic dynamics of a three-dimensional Gaussian statistical model. We then compare our analysis to that of a two-dimensional Gaussian statistical model obtained from the higher-dimensional model via introduction of an additional information constraint that resembles the quantum mechanical canonical minimum uncertainty relation. We show that the chaoticity (temporal complexity) of the two-dimensional Gaussian statistical model, quantified by means of the information geometric entropy (IGE) and the Jacobi vector field intensity, is softened with respect to the chaoticity of the three-dimensional Gaussian statistical model.
Suppression of human detrusor smooth muscle excitability and contractility via pharmacological activation of large conductance Ca2+-activated K+ channels
Authors: Hristov Kiril L. , Parajuli Shankar P. , Soder Rupal P. , Cheng Qiuping , Rovner Eric S. , Petkov Georgi V.
Published: March 2012

Overactive bladder syndrome is frequently associated with increased detrusor smooth muscle (DSM) contractility. We tested the hypothesis that pharmacological activation of the large-conductance voltage- and Ca2+-activated K+ (BK) channel with NS-1619, a selective BK channel opener, reduces the excitability and contractility of human DSM. We used the amphotericin-perforated whole cell patch-clamp technique on freshly isolated human DSM cells, live-cell Ca2+ imaging, and isometric DSM tension recordings of human DSM strips obtained from open bladder surgeries. NS-1619 (30 μM) significantly increased the amplitude of the voltage step-induced whole cell BK currents, and this effect was abolished by pretreatment with 200 nM iberiotoxin (IBTX), a selective BK channel inhibitor. In current-clamp mode, NS-1619 (30 μM) significantly hyperpolarized the resting membrane potential, and the hyperpolarization was reversed by IBTX (200 nM). NS-1619 (30 μM) significantly decreased the intracellular Ca2+ level in isolated human DSM cells. BK channel activation with NS-1619 (30 μM) significantly inhibited the amplitude, muscle force, frequency, duration, and tone of the spontaneous phasic and pharmacologically induced DSM contractions from human DSM isolated strips. IBTX (200 nM) suppressed the inhibitory effects of NS-1619 on spontaneous contractions. The amplitude of electrical field stimulation (0.5–50 Hz)-induced contractions was significantly reduced by NS-1619 (30 μM). Our data suggest that pharmacological activation of BK channels could represent a novel treatment option to control bladder dysfunction in humans.
Cardiac sympathetic activation in patients with pulmonary arterial hypertension
Authors: Mak Susanna , Witte Klaus K. , Al-Hesayen Abdul , Granton John J. , Parker John D.
Published: March 2012

Patients with congestive heart failure (CHF) due to left ventricular (LV) dysfunction have sympathetic activation specifically directed to the myocardium. Although pulmonary arterial hypertension (PAH) is associated with increased systemic sympathetic activity, its impact on sympathetic drive to ventricular myocardium is unknown. Fifteen patients with PAH (9 women; 54 ± 12 years) were studied: 10 with idiopathic PAH and 5 with a connective tissue disorder. We measured hemodynamics, as well as radiolabeled and endogenous concentrations of arterial and coronary sinus norepinephrine (NE). These measures were repeated after inhaled nitric oxide (NO). Measurement of transcardiac NE concentrations and the cardiac extraction of radiolabeled NE allowed calculation of the corrected transcardiac gradient of NE (CTCG of NE). Comparative data were collected from 15 patients (9 women: 55 ± 12 yr) with normal LV function and 15 patients with CHF (10 women; 53 ± 12 yr). PAH patients had elevated arterial NE concentrations compared with those with normal LV function but were similar to those with CHF. The CTCG of NE was higher in those with PAH than in the normal LV group (3.6 ± 2.2 vs. 1.5 ± 0.9 pmol/ml; P < 0.01) but similar to that seen in those with CHF (3.3 ± 1.4; P = NS). Inhaled NO, which reduced pulmonary artery pressure and increased cardiac output, had no effect on cardiac sympathetic activity. Therefore, cardiac sympathetic activation occurs in PAH. The mechanism of this activation remains uncertain but does not involve elevations in left heart filling pressure.
Mammalian target of rapamycin and the kidney. I. The signaling pathway
Authors: Lieberthal Wilfred , Levine Jerrold S.
Published: March 2012

The mammalian target of rapamycin (mTOR) is a serine/threonine kinase that plays a fundamental role in regulating cellular homeostasis and metabolism. In a two-part review, we examine the complex molecular events involved in the regulation and downstream effects of mTOR, as well as the pivotal role played by this kinase in many renal diseases, particularly acute kidney injury, diabetic nephropathy, and polycystic kidney diseases. Here, in the first part of the review, we provide an overview of the complex signaling events and pathways governing mTOR activity and action. mTOR is a key component of two multiprotein complexes, known as mTOR complex 1 (mTORC1) and 2 (mTORC2). Some proteins are found in both mTORC1 and mTORC2, while others are unique to one or the other complex. Activation of mTORC1 promotes cell growth (increased cellular mass or size) and cell proliferation (increased cell number). mTORC1 acts as a metabolic “sensor,” ensuring that conditions are optimal for both cell growth and proliferation. Its activity is tightly regulated by the availability of amino acids, growth factors, energy stores, and oxygen. The effects of mTORC2 activation are distinct from those of mTORC1. Cellular processes modulated by mTORC2 include cell survival, cell polarity, cytoskeletal organization, and activity of the aldosterone-sensitive sodium channel. Upstream events controlling mTORC2 activity are less well understood than those controlling mTORC1, although growth factors appear to stimulate both complexes. Rapamycin and its analogs inhibit the activity of mTORC1 only, and not that of mTORC2, while the newer “catalytic” mTOR inhibitors affect both complexes.
MicroRNA-126 contributes to renal microvascular heterogeneity of VCAM-1 protein expression in acute inflammation
Authors: Ásgeirsdóttir S. A. , van Solingen C. , Kurniati N. F. , Zwiers P. J. , Heeringa P. , van Meurs M. , Satchell S. C. , Saleem M. A. , Mathieson P. W. , Banas B. , Kamps J. A. A. M. , Rabelink T. J. , van Zonneveld A. J. , Molema G.
Published: March 2012

Endothelial cells in different microvascular segments of the kidney have diverse functions and exhibit differential responsiveness to disease stimuli. The responsible molecular mechanisms are largely unknown. We previously showed that during hemorrhagic shock, VCAM-1 protein was expressed primarily in extraglomerular compartments of the kidney, while E-selectin protein was highly induced in glomeruli only (van Meurs M, Wulfert FM, Knol AJ, de Haes A, Houwertjes M, Aarts LPHJ, Molema G. Shock 29: 291–299, 2008). Here, we investigated the molecular control of expression of these endothelial cell adhesion molecules in mouse models of renal inflammation. Microvascular segment-specific responses to the induction of anti-glomerular basement membrane (anti-GBM), glomerulonephritis and systemic TNF-α treatment showed that E-selectin expression was transcriptionally regulated, with high E-selectin mRNA and protein levels preferentially expressed in the glomerular compartment. In contrast, VCAM-1 mRNA expression was increased in both arterioles and glomeruli, while VCAM-1 protein expression was limited in the glomeruli. These high VCAM-1 mRNA/low VCAM-1 protein levels were accompanied by high local microRNA (miR)-126 and Egfl7 levels, as well as higher Ets1 levels compared with arteriolar expression levels. Using miR-reporter constructs, the functional activity of miR-126 in glomerular endothelial cells could be demonstrated. Moreover, in vivo knockdown of miR-126 function unleashed VCAM-1 protein expression in the glomeruli upon inflammatory challenge. These data imply that miR-126 has a major role in the segmental, heterogenic response of renal microvascular endothelial cells to systemic inflammatory stimuli.
Developmental expression of renal organic anion transporters in rat kidney and its effect on renal secretion of phenolsulfonphthalein
Authors: Nomura Maki , Motohashi Hideyuki , Sekine Hiroko , Katsura Toshiya , Inui Ken-ichi
Published: March 2012

Organic anion transporters (OAT1 and OAT3) and multidrug resistance-associated proteins (MRP2 and MRP4) play important roles in anionic drug secretion in renal proximal tubules. Changes in the expression of such transporters are considered to affect the tubular secretion of anionic drugs. The purpose of this study was to elucidate the developmental changes in the expression of OAT1, OAT3, MRP2, and MRP4 and their effects on the tubular secretion of drugs. The mRNA level of each transporter was measured by real-time PCR, and the protein expression was evaluated by Western blotting and immunohistochemical analysis. In addition, the tubular secretion of phenolsulfonphthalein (PSP) in infant (postnatal day 14) and adult rats was estimated based on in vivo clearance study. The protein expression of organic anion transporters were very low at postnatal day 0 and gradually increased with age. In postnatal day 14 rats, the expression of OAT1 and OAT3 seemed to be at almost mature levels, while MRP2 and MRP4 seemed to be at immature levels. Immunohistochemical analysis in the kidney of postnatal day 0 rats revealed OATs on the basolateral membrane and MRPs on the brush-border membrane. At postnatal day 0, the distribution of these transporters was restricted to the inner cortical region, while after postnatal day 14, it was identical to that in adult kidney. An in vivo clearance study revealed that the tubular secretion of PSP was significantly lower in postnatal day 14 rats than adult rats. These results indicate that age-dependent changes in organic anion transporter expression affect the tubular secretion of anionic drugs in pediatric patients.
Impaired myogenic constriction of the renal afferent arteriole in a mouse model of reduced βENaC expression
Authors: Ge Ying , Gannon Kimberly , Gousset Monette , Liu Ruishing , Murphey Beau , Drummond Heather A.
Published: March 2012

Previous studies demonstrate a role for β epithelial Na+ channel (βENaC) protein as a mediator of myogenic constriction in renal interlobar arteries. However, the importance of βENaC as a mediator of myogenic constriction in renal afferent arterioles, the primary site of development of renal vascular resistance, has not been determined. We colocalized βENaC with smooth muscle α-actin in vascular smooth muscle cells in renal arterioles using immunofluorescence. To determine the importance of βENaC in myogenic constriction in renal afferent arterioles, we used a mouse model of reduced βENaC (βENaC m/m) and examined pressure-induced constrictor responses in the isolated afferent arteriole-attached glomerulus preparation. We found that, in response to a step increase in perfusion pressure from 60 to 120 mmHg, the myogenic tone increased from 4.5 ± 3.7 to 27.3 ± 5.2% in +/+ mice. In contrast, myogenic tone failed to increase with the pressure step in m/m mice (3.9 ± 0.8 to 6.9 ± 1.4%). To determine the importance of βENaC in myogenic renal blood flow (RBF) regulation, we examined the rate of change in renal vascular resistance following a step increase in perfusion pressure in volume-expanded animals. We found that, following a step increase in pressure, the rate of myogenic correction of RBF is inhibited by 75% in βENaC m/m mice. These findings demonstrate that myogenic constriction in afferent arterioles is dependent on normal expression of βENaC.
Innovations in motoneuron synchrony drive rapid temporal modulations in vertebrate acoustic signaling
Authors: Chagnaud Boris P. , Zee Michele C. , Baker Robert , Bass Andrew H.
Published: March 2012

Rapid temporal modulation of acoustic signals among several vertebrate lineages has recently been shown to depend on the actions of superfast muscles. We hypothesized that such fast events, known to require synchronous activation of muscle fibers, would rely on motoneuronal properties adapted to generating a highly synchronous output to sonic muscles. Using intracellular in vivo recordings, we identified a suite of premotor network inputs and intrinsic motoneuronal properties synchronizing the oscillatory-like, simultaneous activation of superfast muscles at high gamma frequencies in fish. Motoneurons lacked spontaneous activity, firing synchronously only at the frequency of premotor excitatory input. Population-level motoneuronal output generated a spike-like, vocal nerve volley that directly determines muscle contraction rate and, in turn, natural call frequency. In the absence of vocal output, motoneurons showed low excitability and a weak afterhyperpolarization, leading to rapid accommodation in firing rate. By contrast, vocal activity was accompanied by a prominent afterhyperpolarization, indicating a dependency on network activity. Local injection of a GABAAreceptor antagonist demonstrated the necessity of electrophysiologically and immunohistochemically confirmed inhibitory GABAergic input for motoneuronal synchrony and vocalization. Numerous transneuronally labeled motoneurons following single-cell neurobiotin injection together with electrophysiological collision experiments confirmed gap junctional coupling, known to contribute to synchronous activity in other neural networks. Motoneuronal synchrony at the premotor input frequency was maintained during differential recruitment of variably sized motoneurons. Differential motoneuron recruitment led, however, to amplitude modulation (AM) of vocal output and, hence, natural call AM. In summary, motoneuronal intrinsic properties, in particular low excitability, predisposed vocal motoneurons to the synchronizing influences of premotor inputs to translate a temporal input code into a coincident and extremely synchronous, but variable-amplitude, output code. We propose an analogous suite of neuronal properties as a key innovation underlying similarly rapid acoustic events observed among amphibians, reptiles, birds, and mammals.
Orbitofrontal cortical activity during repeated free choice
Authors: Campos Michael , Koppitch Kari , Andersen Richard A. , Shimojo Shinsuke
Published: March 2012

Neurons in the orbitofrontal cortex (OFC) have been shown to encode subjective values, suggesting a role in preference-based decision-making, although the precise relation to choice behavior is unclear. In a repeated two-choice task, subjective values of each choice can account for aggregate choice behavior, which is the overall likelihood of choosing one option over the other. Individual choices, however, are impossible to predict with knowledge of relative subjective values alone. In this study we investigated the role of internal factors in choice behavior with a simple but novel free-choice task and simultaneous recording from individual neurons in nonhuman primate OFC. We found that, first, the observed sequences of choice behavior included periods of exceptionally long runs of each of two available options and periods of frequent switching. Neither a satiety-based mechanism nor a random selection process could explain the observed choice behavior. Second, OFC neurons encode important features of the choice behavior. These features include activity selective for exceptionally long runs of a given choice (stay selectivity) as well as activity selective for switches between choices (switch selectivity). These results suggest that OFC neural activity, in addition to encoding subjective values on a long timescale that is sensitive to satiety, also encodes a signal that fluctuates on a shorter timescale and thereby reflects some of the statistically improbable aspects of free-choice behavior.
Coupled Fixed‐Point Theorems for Contractions in Partially Ordered Metric Spaces and Applications
Authors: Gordji M. Eshaghi , Cho Y. J. , Ghods S. , Ghods M. , Dehkordi M. Hadian
Published: March 2012

Bhaskar and Lakshmikantham (2006) showed the existence of coupled coincidence points of a mapping F from X × X into X and a mapping g from X into X with some applications. The aim of this paper is to extend the results of Bhaskar and Lakshmikantham and improve the recent fixed‐point theorems due to Bessem Samet (2010). Indeed, we introduce the definition of generalized g‐Meir‐Keeler type contractions and prove some coupled fixed point theorems under a generalized g‐Meir‐Keeler‐contractive condition. Also, some applications of the main results in this paper are given.
Modeling Critical Forest Habitat in the Southern Coal Fields of West Virginia
Authors: Maxwell Aaron E. , Strager Michael P. , Yuill Charles B. , Petty J. Todd
Published: March 2012

Throughout the Central Appalachians of the United States resource extraction primarily from coal mining has contributed to the majority of the forest conversion to barren and reclaimed pasture and grass. The loss of forests in this ecoregion is significantly impacting biodiversity at a regional scale. Since not all forest stands provide equal levels of ecological functions, it is critical to identify and map existing forested resources by the benefits that accrue from their unique spatial patterns, watershed drainage, and landscape positions. We utilized spatial analysis and remote sensing techniques to define critical forest characteristics. The characteristics were defined by applying a forest fragmentation model utilizing morphological image analysis, defining headwater catchments at a 1 : 24,000 scale, and deriving ecological land units (ELUs) from elevation data. Once critical forest values were calculated, it was possible to identify clusters of critical stands using spatial statistics. This spatially explicit method for modeling forest habitat could be implemented as a tool for assessing the impact of resource extraction and aid in the conservation of critical forest habitat throughout a landscape.
The Progress of TiO2 Nanocrystals Doped with Rare Earth Ions
Authors: Liu Hai , Yu Lixin , Chen Weifan , Li Yingyi
Published: March 2012

In the past decades, TiO2 nanocrystals (NCs) have been widely studied in the fields of photoelectric devices, optical communication, and environment for their stability in aqueous solution, being nontoxic, cheapness, and so on. Among the three crystalline phases of TiO2, anatase TiO2 NCs are the best crystallized phase of solar energy conversion. However, the disadvantages of high band gap energy (3.2 ev) and the long lifetime of photogenerated electrons and holes limit its photocatalytic activity severely. Therefore, TiO2 NCs doped with metal ions is available way to inhibit the transformation from anatase to rutile. Besides, these metal ions will concentrate on the surface of TiO2 NCs. All above can enhance the photoactivity of TiO2 NCs. In this paper, we mainly outlined the different characterization brought about in the aspect of nanooptics and photocatalytics due to metal ions added in. Also, the paper mainly concentrated on the progress of TiO2 NCs doped with rare earth (RE) ions.
Approximate n‐Lie Homomorphisms and Jordan n‐Lie Homomorphisms on n‐Lie Algebras
Authors: Gordji M. Eshaghi , Kim G. H.
Published: March 2012

Using fixed point methods, we establish the stability of n‐Lie homomorphisms and Jordan n‐Lie homomorphisms on n‐Lie algebras associated to the following generalized Jensen functional equation .
Bohm Quantum Trajectories of Scalar Field in Trans-Planckian Physics
Authors: Huang Jung-Jeng
Published: March 2012

In lattice Schrödinger picture, we investigate the possible effects of trans-Planckian physics on the quantum trajectories of scalar field in de Sitter space within the framework of the pilot-wave theory of de Broglie and Bohm. For the massless minimally coupled scalar field and the Corley-Jacobson type dispersion relation with sextic correction to the standard-squared linear relation, we obtain the time evolution of vacuum state of the scalar field during slow-roll inflation. We find that there exists a transition in the evolution of the quantum trajectory from well before horizon exit to well after horizon exit, which provides a possible mechanism to solve the riddle of the smallness of the cosmological constant.
Endothelial Progenitors as Tools to Study Vascular Disease
Authors: Medina Reinhold J. , O'Neill Christina L. , O'Doherty T. Michelle , Wilson Sarah E. J. , Stitt Alan W.
Published: March 2012

Endothelial progenitor cells (EPCs) have great clinical value because they can be used as diagnostic biomarkers and as a cellular therapy for promoting vascular repair of ischaemic tissues. However, EPCs also have an additional research value in vascular disease modelling to interrogate human disease mechanisms. The term EPC is used to describe a diverse variety of cells, and we have identified a specific EPC subtype called outgrowth endothelial cell (OEC) as the best candidate for vascular disease modelling because of its high-proliferative potential and unambiguous endothelial commitment. OECs are isolated from human blood and can be exposed to pathologic conditions (forward approach) or be isolated from patients (reverse approach) in order to study vascular human disease. The use of OECs for modelling vascular disease will contribute greatly to improving our understanding of endothelial pathogenesis, which will potentially lead to the discovery of novel therapeutic strategies for vascular diseases.
A Modified PSO Algorithm for Minimizing the Total Costs of Resources in MRCPSP
Authors: Khalilzadeh Mohammad , Kianfar Fereydoon , Shirzadeh Chaleshtari Ali , Shadrokh Shahram , Ranjbar Mohammad
Published: March 2012

We introduce a multimode resource‐constrained project scheduling problem with finish‐to‐start precedence relations among project activities, considering renewable and nonrenewable resource costs. We assume that renewable resources are rented and are not available in all periods of time of the project. In other words, there is a mandated ready date as well as a due date for each renewable resource type so that no resource is used before its ready date. However, the resources are permitted to be used after their due dates by paying penalty costs. The objective is to minimize the total costs of both renewable and nonrenewable resource usage. This problem is called multimode resource‐constrained project scheduling problem with minimization of total weighted resource tardiness penalty cost (MRCPSP‐TWRTPC), where, for each activity, both renewable and nonrenewable resource requirements depend on activity mode. For this problem, we present a metaheuristic algorithm based on a modified Particle Swarm Optimization (PSO) approach introduced by Tchomté and Gourgand which uses a modified rule for the displacement of particles. We present a prioritization rule for activities and several improvement and local search methods. Experimental results reveal the effectiveness and efficiency of the proposed algorithm for the problem in question.
Immunotherapy Using Dendritic Cells against Multiple Myeloma: How to Improve?
Authors: Nguyen-Pham Thanh-Nhan , Lee Yoon-Kyung , Kim Hyeoung-Joon , Lee Je-Jung
Published: March 2012

Multiple myeloma (MM) is a good target disease in which one can apply cellular immunotherapy, which is based on the graft-versus-myeloma effect. This role of immune effector cells provides the framework for the development of immune-based therapeutic options that use antigen-presenting cells (APCs) with increased potency, such as dendritic cells (DCs), in MM. Current isolated idiotype (Id), myeloma cell lysates, myeloma dying cells, DC-myeloma hybrids, or DC transfected with tumor-derived RNA has been used for immunotherapy with DCs. Immunological inhibitory cytokines, such as TGF-β, IL-10, IL-6 and VEGF, which are produced from myeloma cells, can modulate antitumor host immune response, including the abrogation of DC function, by constitutive activation of STAT3. Therefore, even the immune responses have been observed in clinical trials, the clinical response was rarely improved following DC vaccinations in MM patients. We are going to discuss how to improve the efficacy of DC vaccination in MM.
Convergence Theorems for Infinite Family of Multivalued Quasi‐Nonexpansive Mappings in Uniformly Convex Banach Spaces
Authors: Bunyawat Aunyarat , Suantai Suthep
Published: March 2012

We introduce an iterative method for finding a common fixed
point of a countable family of multivalued quasi‐nonexpansive mapping {Ti} in a
uniformly convex Banach space. We prove that under certain control conditions, the iterative sequence generated by our method is an approximating fixed point
sequence of each Ti. Some strong convergence theorems of the proposed method
are also obtained for the following cases: all Ti are continuous and one of Ti is
hemicompact, and the domain K is compact.
Physical Properties and Biocompatibility of a Core-Sheath Structure Composite Scaffold for Bone Tissue Engineering In Vitro
Authors: Wang Chuangjian , Meng Guolin , Zhang Laquan , Xiong Zuo , Liu Jian
Published: March 2012

Scaffolds play a critical role in the practical realization of bone tissue engineering. The purpose of this study was to assess whether a core-sheath structure composite scaffold possesses admirable physical properties and biocompatibility in vitro. A novel scaffold composed of poly(lactic-co-glycolic acid)/β-tricalcium phosphate (PLGA/β-TCP) skeleton wrapped with Type I collagen via low-temperature deposition manufacturing (LDM) was prepared, and bone mesenchymal stem cells (BMSCs) were used to evaluate cell behavior on the scaffold. PLGA/β-TCP skeleton was chosen as the control group. Physical properties were evaluated by pority ratio, compressive strength, and Young’s modulus. Scanning electron microscope (SEM) was used to study morphology of cells. Hydrophilicity was evaluated by water absorption ratio. Cell proliferation was tested by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay (MTT). Osteogenic differentiation of BMSCs was evaluated by alkaline phosphates activity (ALP). The results indicated that physical properties of the novel scaffold were as good as those of the control group, hydrophilicity was observably better (P<0.01) than that of control group, and abilities of proliferation and osteogenic differentiation of BMSCs on novel scaffold were significantly greater (P<0.05) than those of control group, which suggests that the novel scaffold possesses preferable characteristics and have high value in bone tissue engineering.
Influence of RANEY Nickel on the Formation of Intermediates in the Degradation of Lignin
Authors: Forchheim Daniel , Hornung Ursel , Kempe Philipp , Kruse Andrea , Steinbach David
Published: March 2012

Lignin forms an important part of lignocellulosic biomass and is an abundantly available residue. It is a potential renewable source of phenol. Liquefaction of enzymatic hydrolysis lignin as well as catalytical hydrodeoxygenation of the main intermediates in the degradation of lignin, that is, catechol and guaiacol, was studied. The cleavage of the ether bonds, which are abundant in the molecular structure of lignin, can be realised in near-critical water (573 to 673 K, 20 to 30 MPa). Hydrothermal treatment in this context provides high selectivity in respect to hydroxybenzenes, especially catechol. RANEY Nickel was found to be an adequate catalyst for hydrodeoxygenation. Although it does not influence the cleavage of ether bonds, RANEY Nickel favours the production of phenol from both lignin and catechol. The main product from hydrodeoxygenation of guaiacol with RANEY Nickel was cyclohexanol. Reaction mechanism and kinetics of the degradation of guaiacol were explored.
A Class of Numerical Methods for the Solution of Fourth-Order Ordinary Differential Equations in Polar Coordinates
Authors: Talwar Jyoti , Mohanty R. K.
Published: March 2012

In this piece of work using only three grid points, we propose two sets of numerical methods in a coupled manner for the solution of fourth-order ordinary differential equation uiv(x)=f(x,u(x),u′(x),u′′(x),u′′′(x)), a<x<b, subject to boundary conditions u(a)=A0, u′(a)=A1, u(b)=B0, and u′(b)=B1, where A0, A1, B0, and B1 are real constants. We do not require to discretize the boundary conditions. The derivative of the solution is obtained as a byproduct of the discretization procedure. We use block iterative method and tridiagonal solver to obtain the solution in both cases. Convergence analysis is discussed and numerical results are provided to show the accuracy and usefulness of the proposed methods.
Nonprofessional Phagocytosis Can Facilitate Herpesvirus Entry into Ocular Cells
Authors: Tiwari Vaibhav , Shukla Deepak
Published: March 2012

Phagocytosis is a major mechanism by which the mediators of innate immunity thwart microbial infections. Here we demonstrate that human herpesviruses may have evolved a common mechanism to exploit a phagocytosis-like entrapment to gain entry into ocular cells. While herpes simplex virus-1 (HSV-1) causes corneal keratitis, cytomegalovirus (CMV) is associated with retinitis in immunocompromised individuals. A third herpesvirus, human herpesvirus-8 (HHV-8), is crucial for the pathogenesis of Kaposi’s sarcoma, a common AIDS-related tumor of eyelid and conjunctiva. Using laser scanning confocal microscopy, we show that successful infection of ocular cell types by all the three viruses, belonging to three divergent subfamilies of herpesviruses, is facilitated by induction of F-actin rich membrane protrusions. Inhibitors of F-actin polymerization and membrane protrusion formation, cytochalasin D and latrunculin B, were able to block infection by all three viruses. Similar inhibition was seen by blocking phosphoinositide 3 kinase signaling, which is required for microbial phagocytosis. Transmission electron microscopy data using human corneal fibroblasts for HSV-1, human retinal pigment epithelial cells for CMV, and human conjunctival epithelial cells for HHV-8 are consistent with the possibility that pseudopod-like membrane protrusions facilitate virus uptake by the ocular cells. Our findings suggest a novel mechanism by which the nonprofessional mediators of phagocytosis can be infected by human herpesviruses.
Cardioprotective Effect of the CompoundYangshenGranule in Rat Models with Acute Myocardial Infarction
Authors: Ming Xie , Tongshen Wang , Delin Wu , Ronghua Zhao
Published: March 2012

The protective effect of CompoundYangshenGranules was observed in myocardial infarction rat model. Rats were randomly divided into 6 groups: the model group, the control group (sham operated), the positive drug group, and small, medium, and large dosage of theYangshengranule groups, respectively. The rats in the 3Yangshengranule groups were orally administrated with 0.7 g/kg, 1.4 g/kg, and 2.8 g/kg for 7 consecutive days, whereas the rats of the positive drug group treated with 0.14 g/kg of Danshen Dropping Pills, and rats in the control and model groups orally administrated with saline. The rat model of acute myocardial infarction was established with ligation of coronary artery. Electrocardiograms at different time points, the blood rheology, myocardial enzymes, infarct size, and myocardial morphologic changes were measured. The results demonstrated that the granules could improve blood rheology, decrease st-segment of electrocardiograms and the activities of LDH and CK in serum, reduce myocardial infarction size, and alleviate myocardial histopathologic changes. In addition, the effect of the granules depended on the dose administrated orally. The results suggest that theYangshengranules could produce cardioprotection effect and have potential benefits in the prevention of ischemic heart disease.
Burden of Human Papillomavirus among Haitian Immigrants in Miami, Florida: Community-Based Participatory Research in Action
Authors: Kobetz Erin , Kish Jonathan K. , Campos Nicole G. , Koru-Sengul Tulay , Bishop Ian , Lipshultz Hannah , Barton Betsy , Barbee Lindley
Published: March 2012

Background. Haitian immigrant women residing in Little Haiti, a large ethnic enclave in Miami-Dade County, experience the highest cervical cancer incidence rates in South Florida. While this disparity primarily reflects lack of access to screening with cervical cytology, the burden of human papillomavirus (HPV) which causes virtually all cases of cervical cancer worldwide, varies by population and may contribute to excess rate of disease. Our study examined the prevalence of oncogenic and nononcogenic HPV types and risk factors for HPV infection in Little Haiti.Methods. As part of an ongoing community-based participatory research initiative, community health workers recruited study participants between 2007 and 2008, instructed women on self-collecting cervicovaginal specimens, and collected sociodemographic and healthcare access data.Results. Of the 242 women who contributed adequate specimens, the overall prevalence of HPV was 20.7%, with oncogenic HPV infections (13.2% of women) outnumbering nononcogenic infections (7.4%). Age-specific prevalence of oncogenic HPV was highest in women 18–30 years (38.9%) although the prevalence of oncogenic HPV does not appear to be elevated relative to the general U.S. population. The high prevalence of oncogenic types in women over 60 years may indicate a substantial number of persistent infections at high risk of progression to precancer.
On Subclasses of Analytic Functions with respect to Symmetrical Points
Authors: Arif Muhammad , Noor Khalida Inayat , Khan Rafiullah
Published: March 2012

In our present investigation, motivated from Noor work, we define the class (b) of functions of bounded radius rotation of complex order b with respect to symmetrical points and learn some of its basic properties. We also apply this concept to define the class . We study some interesting results, including arc length, coefficient difference, and univalence sufficient condition for this class.
Adaptive Modified Function Projective Synchronization between Two Different Hyperchaotic Dynamical Systems
Authors: El-Dessoky M. M. , Yassen M. T. , Saleh E.
Published: March 2012

This work investigates modified function projective synchronization between two different hyperchaotic dynamical systems, namely, hyperchaotic Lorenz system and hyperchaotic Chen system with fully unknown parameters. Based on Lyapunov stability theory, the adaptive control law and the parameter update law are derived to achieve modified function projective synchronized between two diffierent hyperchaotic dynamical systems. Numerical simulations are presented to demonstrate the effectiveness of the proposed adaptive controllers.
Investigation of Range Profiles from a Simplified Ship on Rough Sea Surface and Its Multipath Imaging Mechanisms
Authors: He Siyuan , Zhang Fan , Hu Weidong , Zhuang Lei , Ye Xingbin , Zhu Guoqiang
Published: March 2012

The range profiles of a two-dimension (2 D) perfect electric conductor (PEC) ship on a wind-driven rough sea surface are derived by performing an inverse discrete Fourier transform (IDFT) on the wide band backscattered field. The rough sea surface is assuming to be a PEC surface. The back scattered field is computed based on EM numerical simulation when the frequencies are sampled between 100 MHz and 700 MHz. Considering the strong coupling interactions between the ship and sea, the complicated multipath effect to the range profile characteristics is fully analyzed based on the multipath imaging mechanisms. The coupling mechanisms could be explained by means of ray theory prediction and numerical extraction of the coupling currents. The comparison of the range profile locations between ray theory prediction and surface current simulation is implemented and analyzed in this paper. Finally, the influence of different sea states on the radar target signatures has been examined and discussed.
Static and Vibrational Analysis of Partially Composite Beams Using the Weak‐Form Quadrature Element Method
Authors: Shen Zhiqiang , Zhong Hongzhi
Published: March 2012

Deformation of partially composite beams under distributed loading and free vibrations of partially composite beams under various boundary conditions are examined in this paper. The weak‐form quadrature element method, which is characterized by direct evaluation of the integrals involved in the variational description of a problem, is used. One quadrature element is normally sufficient for a partially composite beam regardless of the magnitude of the shear connection stiffness. The number of integration points in a quadrature element is adjustable in accordance with convergence requirement. Results are compared with those of various finite element formulations. It is shown that the weak form quadrature element solution for partially composite beams is free of slip locking, and high computational accuracy is achieved with smaller number of degrees of freedom. Besides, it is found that longitudinal inertia of motion cannot be simply neglected in assessment of dynamic behavior of partially composite beams.
Acetylation: A Novel Link between Double-Strand Break Repair and Autophagy
Authors: Shubassi Ghadeer , Robert Thomas , Vanoli Fabio , Minucci Saverio , Foiani Marco
Published: March 2012

Histone deacetylase (HDAC) inhibitors are clinically relevant because they are used as anticancer drugs. Recent evidence sheds light on an intriguing connection among the DNA damage response (DDR), protein acetylation, and autophagy. HDAC inhibitors have been shown to counteract key steps in the cellular response to double-strand break formation by affecting checkpoint activation, homologous recombination–mediated repair of DNA lesions, and stability of crucial enzymes involved in resection of DNA ends. The degradation of the resection factors depends on autophagy, which plays a detrimental role when cells are in a hyperacetylated state and experience treatment with radiomimetic anticancer drugs. Future work will be required to further investigate the mechanisms underlying the link between acetylation, autophagy, and the DDR, as well as the significance of mTORC1 inhibitors, which are potent inducers of autophagy that are now used in cancer treatment. Cancer Res; 72(6); 1332–5. ©2012 AACR.
Leveling the Playing Field: Bringing Development of Biomarkers and Molecular Diagnostics up to the Standards for Drug Development
Authors: Poste George , Carbone David P. , Parkinson David R. , Verweij Jaap , Hewitt Stephen M. , Jessup J. Milburn
Published: March 2012

Molecular diagnostics are becoming increasingly important in clinical research to stratify or identify molecularly profiled patient cohorts for targeted therapies, to modify the dose of a therapeutic, and to assess early response to therapy or monitor patients. Molecular diagnostics can also be used to identify the pharmacogenetic risk of adverse drug reactions. The articles in this CCR Focus section on molecular diagnosis describe the development and use of markers to guide medical decisions regarding cancer patients. They define sources of preanalytic variability that need to be minimized, as well as the regulatory and financial challenges involved in developing diagnostics and integrating them into clinical practice. They also outline a National Cancer Institute program to assist diagnostic development. Molecular diagnostic clinical tests require rigor in their development and clinical validation, with sensitivity, specificity, and validity comparable to those required for the development of therapeutics. These diagnostics must be offered at a realistic cost that reflects both their clinical value and the costs associated with their development. When genome-sequencing technologies move into the clinic, they must be integrated with and traceable to current technology because they may identify more efficient and accurate approaches to drug development. In addition, regulators may define progressive drug approval for companion diagnostics that requires further evidence regarding efficacy and safety before full approval can be achieved. One way to accomplish this is to emphasize phase IV postmarketing, hypothesis-driven clinical trials with biological characterization that would permit an accurate definition of the association of low-prevalence gene alterations with toxicity or response in large cohorts. Clin Cancer Res; 18(6); 1515–23. ©2012 AACR.
Neural Connectivity of the Pedunculopontine Nucleus in Relation to Walking Ability in Chronic Patients with Intracerebral Hemorrhage
Authors: Yeo Sang Seok , Lee Dong Gyu , Choi Byung Yeon , Chang Chul Hoon , Jung Young Jin , Kim Seong Ho , Chang Min Cheol , Jang Sung Ho
Published: March 2012

Objectives: As the mesencephalic locomotor center, the pedunculopontine nucleus (PPN) is known to be involved in control of locomotor function. We investigated neural connectivity of the PPN in relation to walking ability in chronic patients with spontaneous intracerebral hemorrhage. Methods: Forty-three consecutive chronic patients with subcortical hemorrhage and 20 healthy control subjects were recruited. A seed region of interest was manually drawn on the PPN and connectivity of the PPN was measured. Results: In the affected hemisphere, connectivity with the ipsilesional cerebellar locomotor center and connectivity with the contralesional pontine locomotor center were decreased in patients who could not walk, compared with patients who could walk and normal controls (p < 0.05). Conclusions: Connectivity between the PPN and ipsi-lesional cerebellum locomotor center and contralesional pontine locomotor center in the affected hemisphere appears to be related to walking ability.
A Vedic Example of `No Doubt' Used as a Parenthetic Clause
Authors: Bodewitz
Published: March 2012

No Abstract