bluuebunny/crossref_metadata_2025 huggingface dataset:
Differential effects of TGF‐β and FGF‐2 on in vitro proliferation and migration of primate retinal endothelial and Müller cells
Authors: Romo Phillip , Madigan Michele C. , Provis Jan M. , Cullen Karen M.
Published: July 2010

Purpose:  During retinal development, the pattern of blood vessel formation depends upon the combined effects of proliferation and migration of endothelial cells, astrocytes and Müller cells. In this study, we investigated the potential for transforming growth factor‐β (TGF‐β) and fibroblast growth factor (FGF‐2) to influence this process by regulating proliferation and migration of retinal endothelial and macroglial cells.

Methods:  We assessed the effects of exogenous TGF‐β and FGF‐2 on the proliferation and migration of cultured endothelial (RF/6A) and Müller cell (MIO‐M1) lines. Cell proliferation was measured using a MTT [3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide) colorimetric assay over 72 hr. Cell migration was measured using a scratch‐wound assay over 72 hr.

Results:  Transforming growth factor‐β inhibited the proliferation of endothelial and Müller cells and inhibited the migration of Müller cells, but not endothelial cells, compared to untreated controls. Conversely, FGF‐2 increased endothelial cell proliferation but inhibited endothelial cell migration. Fibroblast growth factor‐2 increased migration of Müller cells but had little effect on proliferation except at higher concentrations (20 ng/ml).

Conclusion:  Taken together, these observations indicate that TGF‐β and FGF could work in concert to inhibit endothelial cell proliferation and migration, respectively; this may have implications for establishing and maintaining the avascular zone of primate fovea.
An Experimental Data Based Correction Method of Biomass Gasification Equilibrium Modeling
Authors: Damiani L. , Trucco A.
Published: July 2010

This paper presents a modified equilibrium simulation model for biomass gasification performance prediction. The model, implemented in the MATLAB-SIMULINK® environment, is able to calculate the reactor main operating parameters such as reaction temperature, gas composition, gas flow rate and solid product (typically charcoal). The comparison of model output with experimental data puts in evidence the insufficient precision of equilibrium models due to their incapability of taking into account the nonequilibrium effects always present in the gasification process. To obtain a better prediction of measured values, the pure equilibrium model has been modified on the basis of literature experimental data, introducing semi-empirical relations with the aim to consider the most meaningful effects of nonequilibrium. The results demonstrate that this modification leads to an increased precision of the model in reproducing experimental data.
An Air-Based Cavity-Receiver for Solar Trough Concentrators
Authors: Bader Roman , Barbato Maurizio , Pedretti Andrea , Steinfeld Aldo
Published: July 2010

A cylindrical cavity-receiver containing a tubular absorber that uses air as the heat transfer fluid is proposed for a novel solar trough concentrator design. A numerical heat transfer model is developed to determine the receiver’s absorption efficiency and pumping power requirement. The 2D steady-state energy conservation equation coupling radiation, convection, and conduction heat transfer is formulated and solved numerically by finite volume techniques. The Monte Carlo ray-tracing and radiosity methods are applied to establish the solar radiation distribution and radiative exchange within the receiver. Simulations were conducted for a 50 m-long and 9.5 m-wide collector section with 120°C air inlet temperature, and air mass flows in the range 0.1–1.2 kg/s. Outlet air temperatures ranged from 260°C to 601°C, and corresponding absorption efficiencies varied between 60% and 18%. Main heat losses integrated over the receiver length were due to reflection and spillage at the receiver’s windowed aperture, amounting to 13% and 9% of the solar power input, respectively. The pressure drop along the 50 m module was in the range 0.23–11.84 mbars, resulting in isentropic pumping power requirements of 6.45×10−4−0.395% of the solar power input.
The Influence of Modeling Separate Neuromuscular Compartments on the Force and Moment Generating Capacities of Muscles of the Feline Hindlimb
Authors: MacFadden Lisa N. , Brown Nicholas A. T.
Published: July 2010

Functional electrical stimulation (FES) has the capacity to regenerate motion for individuals with spinal cord injuries. However, it is not straightforward to determine the stimulation parameters to generate a coordinated movement. Musculoskeletal models can provide a noninvasive simulation environment to estimate muscle force and activation timing sequences for a variety of tasks. Therefore, the purpose of this study was to develop a musculoskeletal model of the feline hindlimb for simulations to determine stimulation parameters for intrafascicular multielectrode stimulation (a method of FES). Additionally, we aimed to explore the differences in modeling neuromuscular compartments compared with representing these muscles as a single line of action. When comparing the modeled neuromuscular compartments of biceps femoris, sartorius, and semimembranosus to representations of these muscles as a single line of action, we observed that modeling the neuromuscular compartments of these three muscles generated different force and moment generating capacities when compared with single muscle representations. Differences as large as 4 N m (∼400% in biceps femoris) were computed between the summed moments of the neuromuscular compartments and the single muscle representations. Therefore, modeling neuromuscular compartments may be necessary to represent physiologically reasonable force and moment generating capacities of the feline hindlimb.
High-aspect-ratio deep Si etching in SF6/O2 plasma. I. Characteristics of radical reactions with high-aspect-ratio patterns
Authors: Maruyama Takahiro , Narukage Takeshi , Onuki Ryota , Fujiwara Nobuo
Published: July 2010

This article presents a study of the characteristics of radicals in high-aspect-ratio deep Si etching by continuous-type SF6/O2 plasmas. A parametric study of etched depths clearly shows that the Si etch rates are dependent on concentrations of F atoms but independent of ion energy and substrate temperature. Results of Monte Carlo simulation based on a Knudsen transport model provide a remarkably good fit for experimental results on aspect-ratio-dependent etching. Comparison of the experimental data and results of simulation shows that the probability of a F atom reacting with the Si surface is 0.4–0.45 if the probability of loss at sidewall surfaces for F atoms is negligible. Results also indicate that the latter probability is, in fact, extremely small (<0.005).
Dopaminergic Network Differences in Human Impulsivity
Authors: Buckholtz Joshua W. , Treadway Michael T. , Cowan Ronald L. , Woodward Neil D. , Li Rui , Ansari M. Sib , Baldwin Ronald M. , Schwartzman Ashley N. , Shelby Evan S. , Smith Clarence E. , Kessler Robert M. , Zald David H.
Published: July 2010

Highly impulsive individuals have diminished regulatory control of dopamine release.
Quantifying
E. coli
Proteome and Transcriptome with Single-Molecule Sensitivity in Single Cells
Authors: Taniguchi Yuichi , Choi Paul J. , Li Gene-Wei , Chen Huiyi , Babu Mohan , Hearn Jeremy , Emili Andrew , Xie X. Sunney
Published: July 2010

Devil in the Detail

Genetically identical cells in the same environment can show variation in gene expression that may cause phenotypic variation at the single-cell level. But how noisy are most genes?

Taniguchi
et al.

(p.
533
; see the Perspective by

Tyagi

) now report single-cell global profiling of both messenger RNA (mRNA) and proteins in
Escherichia coli
using a yellow fluorescent protein fusion library. As well as a common extrinsic noise in high-abundance proteins, large fluctuations were observed in low-abundance proteins. Remarkably, in single-cell experiments, mRNA and protein levels for the same gene were uncorrelated.
Identification of a Cell of Origin for Human Prostate Cancer
Authors: Goldstein Andrew S. , Huang Jiaoti , Guo Changyong , Garraway Isla P. , Witte Owen N.
Published: July 2010

Another Cell Culprit in Prostate Cancer

A recent controversial hypothesis about the cellular origins of human cancer, the so-called “cancer stem cell hypothesis,” has fueled interest in identifying the specific cell types that give rise to common epithelial cancers. A single, well-defined cell of origin could, in principle, lead to more effective targeted therapies. Based on histological evidence and/or studies of mouse tumors, luminal cells are believed to be the cell of origin in prostate cancer. Now, using functional assays of cells derived from benign human prostate tissue,

Goldstein
et al.

(p.
568
) find that a different cell type, basal cells, can give rise in mice to prostate tumors that closely resemble human prostate tumors. Thus, the cellular origin of prostate cancer may be more complex than anticipated.
Is Pharma Running Out of Brainy Ideas?
Authors: Miller Greg
Published: July 2010

Recent cutbacks raise concerns about the future of drug development for nervous system disorders.
Function of an Implanted Tissue Glucose Sensor for More than 1 Year in Animals
Authors: Gough David A. , Kumosa Lucas S. , Routh Timothy L. , Lin Joe T. , Lucisano Joseph Y.
Published: July 2010

An implanted tissue glucose sensor can provide stable readings of glucose concentrations for more than a year.
Power in Numbers
Authors: Morozov Alexei
Published: July 2010

A multidisciplinary effort begins to unravel the genomic portrait of prostate cancer.
Evaluation of Extracellular Subviral Particles of Dengue Virus Type 2 and Japanese Encephalitis Virus Produced bySpodoptera frugiperdaCells for Use as Vaccine and Diagnostic Antigens
Authors: Kuwahara Miwa , Konishi Eiji
Published: July 2010

New or improved vaccines against dengue virus types 1 to 4 (DENV1 to DENV4) and Japanese encephalitis virus (JEV), the causative agents of dengue fever and Japanese encephalitis (JE), respectively, are urgently required. The use of noninfectious subviral extracellular particles (EPs) is an inexpensive and safe strategy for the production of protein-based flavivirus vaccines. Although coexpression of premembrane (prM) and envelope (E) proteins has been demonstrated to produce EPs in mammalian cells, low yields have hindered their commercial application. Therefore, we used an insect cell expression system withSpodoptera frugiperda-derived Sf9 cells to investigate high-level production of DENV2 and JEV EPs. Sf9 cells transfected with theprMandEgenes of DENV2 or JEV secreted corresponding viral antigens in a particulate form that were biochemically and biophysically equivalent to the authentic antigens obtained from infected C6/36 mosquito cells. Additionally, equivalent neutralizing antibody titers were induced in mice immunized either with EPs produced by transfected Sf9 cells or with EPs produced by transfected mammalian cells, in the context of coimmunization with a DNA vaccine that expresses EPs. Furthermore, the results of an enzyme-linked immunosorbent assay (ELISA) using an EP antigen derived from Sf9 cells correlated significantly with the results obtained by a neutralization test and an ELISA using an EP antigen derived from mammalian cells. Finally, Sf9 cells could produce 10- to 100-fold larger amounts of E antigen than mammalian cells. These results indicate the potential of Sf9 cells for high-level production of flavivirus protein vaccines and diagnostic antigens.
Virulence Genes and Genotypic Associations in Nasal Carriage, Community-Associated Methicillin-Susceptible and Methicillin-Resistant USA400
Staphylococcus aureus
Isolates
Authors: Shukla Sanjay K. , Karow Mary E. , Brady Jennifer M. , Stemper Mary E. , Kislow Jennifer , Moore Natalie , Wroblewski Katherine , Chyou Po-Huang , Warshauer David M. , Reed Kurt D. , Lynfield Ruth , Schwan William R.
Published: July 2010

It is not well understood why strains of community-associated methicillin-resistant
Staphylococcus aureus
(CA-MRSA), a major cause of skin and soft tissue infections, became successful so quickly, overtaking the place of methicillin-sensitive
S. aureus
(MSSA) in many communities. To evaluate the genetic basis of differences in their virulence traits, 293
S. aureus
isolates consisting of three cohorts, genotypically defined clinical CA-MRSA (
n
= 77), clinical MSSA (
n
= 103), and nasal carriage MSSA (
n
= 113), collected over a 19-year period in two Midwestern states in the United States, were (i) extensively genotyped and (ii) screened for 40 known virulence genes which included those for enterotoxins, leukocidins, hemolysins, and surface proteins and several newly identified putative toxin genes from the USA400 lineage of CA-MRSA. Genotypically, nasal carriage and clinical MSSA isolates were much more diverse than was the CA-MRSA group, which was found to be of USA400 lineage only. Virulence gene profiles of the three groups showed that CA-MRSA strains harbored significantly higher percentages (≥95%;
P
value, <0.05) of the
sea
,
sec
,
sec4
,
seg2
,
seh
,
sek
,
sel
,
sel2
,
ear
,
ssl1
,
lpl10
,
lukSF-PV
,
lukD
,
lukE
, and
clfA
genes than did the carriage and the clinical MSSA group (range, 0% to 58%). Genes of the enterotoxin gene cluster,
seg
,
sei
,
sem
,
sen
, and
seo
, were present in the clinical and carriage isolates but not in the CA-MRSA group. These results suggest that the presence of additional virulence factors in USA400 CA-MRSA strains compared to the nasal carriage and clinical MSSA strains probably contributed to their enhanced virulence.
Membrane Uncoating of Intact Enveloped Viruses
Authors: Haywood Anne M.
Published: July 2010

Experiments in the 1960s showed that Sendai virus, a paramyxovirus, fused its membrane with the host plasma membrane. After membrane fusion, the virus spontaneously “uncoated” with diffusion of the viral membrane proteins into the host plasma membrane and a merging of the host and viral membranes. This led to deposit of the viral ribonucleoprotein (RNP) and interior proteins in the cell cytoplasm. Later work showed that the common procedure then used to grow Sendai virus produced damaged, pleomorphic virions. Virions, which were grown under conditions that were not damaging, made a connecting structure between virus and cell at the region where the fusion occurred. The virus did not release its membrane proteins into the host membrane. The viral RNP was seen in the connecting structure in some cases. Uncoating of intact Sendai virus proceeds differently from uncoating described by the current standard model developed long ago with damaged virus. A model of intact paramyxovirus uncoating is presented and compared to what is known about the uncoating of other viruses.
Cellular MicroRNAs 200b and 429 Regulate the Epstein-Barr Virus Switch between Latency and Lytic Replication
Authors: Ellis-Connell Amy L. , Iempridee Tawin , Xu Iris , Mertz Janet E.
Published: July 2010

We previously showed that the cellular proteins ZEB1 and ZEB2/SIP1 both play key roles in regulating the latent-lytic switch of Epstein-Barr Virus (EBV) by repressing
BZLF1
gene expression. We investigated here the effects of cellular microRNA (miRNA) 200 (miR200) family members on the EBV infection status of cells. We show that miR200b and miR429, but not miR200a, can induce EBV-positive cells into lytic replication by downregulating expression of ZEB1 and ZEB2, leading to production of infectious virus. The levels of miR200 family members in EBV-infected cells strongly negatively correlated with the levels of the ZEBs (e.g., −0.89 [
P
< 0.001] for miR429 versus ZEB1) and positively correlated with the degree of EBV lytic gene expression (e.g., 0.73 [
P
< 0.01] for miR429 versus BZLF1). The addition of either miR200b or miR429 to EBV-positive cells led to EBV lytic reactivation in a ZEB-dependent manner; inhibition of these miRNAs led to decreased EBV lytic gene expression. The degree of latent infection by an EBV mutant defective in the primary ZEB-binding site of the EBV BZLF1 promoter was not affected by the addition of these miRNAs. Furthermore, EBV infection of primary blood B cells led to downregulation of these miRNAs and upregulation of ZEB levels. Thus, we conclude that miRNAs 200b and 429 are key regulators via their effects on expression of ZEB1 and ZEB2 of the switch between latent and lytic infection by EBV and, therefore, potential targets for development of new lytic induction therapeutics with which to treat patients with EBV-associated malignancies.
Characterization of the Envelope Glycoproteins Associated with Infectious Hepatitis C Virus
Authors: Vieyres Gabrielle , Thomas Xavier , Descamps Véronique , Duverlie Gilles , Patel Arvind H. , Dubuisson Jean
Published: July 2010

Hepatitis C is caused by an enveloped virus whose entry is mediated by two glycoproteins, namely, E1 and E2, which have been shown to assemble as a noncovalent heterodimer. Despite extensive research in the field of such an important human pathogen, hepatitis C virus (HCV) glycoproteins have only been studied so far in heterologous expression systems, and their organization at the surfaces of infectious virions has not yet been described. Here, we characterized the envelope glycoproteins associated with cell-cultured infectious virions and compared them with their prebudding counterparts. Viral particles were analyzed by ultracentrifugation, and the envelope glycoproteins were characterized by coimmunoprecipitation and receptor pulldown assays. Furthermore, their oligomeric state was determined by sedimentation through sucrose gradients and by separation by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) under nonreducing conditions. In sucrose gradient analyses, HCV envelope glycoproteins were associated with fractions containing the most infectious viral particles. Importantly, besides maturation of some of their glycans, HCV envelope glycoproteins showed a dramatic change in their oligomeric state after incorporation into the viral particle. Indeed, virion-associated E1 and E2 envelope glycoproteins formed large covalent complexes stabilized by disulfide bridges, whereas the intracellular forms of these proteins assembled as noncovalent heterodimers. Furthermore, the virion-associated glycoprotein complexes were recognized by the large extracellular loop of CD81 as well as conformation-sensitive antibodies, indicating that these proteins are in a functional conformation. Overall, our study fills a gap in the description of HCV outer morphology and should guide further investigations into virus entry and assembly.
A practical guide and review of colonoscopic surveillance and chromoendoscopy in patients with colitis
Authors: Rutter Matthew D
Published: July 2010

Patients with longstanding extensive colitis have an increased risk of developing colorectal cancer. The British Society of Gastroenterology has recently published revised guidelines for colitis surveillance, taking into account new evidence supporting chromoendoscopy and the endoscopic resection of certain neoplastic lesions. This article reviews some of the evidence behind this paradigm shift and gives a practical guide to chromoendoscopy.
CLASSIFICATION OF BIANCHI TYPE I SPACETIMES ACCORDING TO THEIR PROPER TELEPARALLEL HOMOTHETIC VECTOR FIELDS IN THE TELEPARALLEL THEORY OF GRAVITATION
Authors: SHABBIR GHULAM , KHAN SUHAIL
Published: July 2010

In this paper we explored teleparallel homothetic vector fields in Bianchi type I spacetimes in the teleparallel theory of gravitation using direct integration technique. It turns out that the dimensions of the teleparallel homothetic vector fields are 4, 5, 7 or 11 which are same in numbers as in general relativity. In the cases of 4, 5 or 7 proper teleparallel homothetic vector fields exist for the special choice of the spacetimes. In the case of 11 teleparallel homothetic vector fields all the torsion components are zero. The homothetic vector fields of general relativity are recovered in this case and the spacetime become Minkowski.
THE STUDY OF INSCRIBED SURFACE OF ARMCHAIR CARBON NANOTUBES
Authors: LU SHENG , CHO CHONGDU
Published: July 2010

It is natural to treat the monolayer crystalline film as the surface fixed by the positions of atoms. However, this type surface is not well-suited to the monolayer crystalline film. It has been discovered that the mechanical properties of a monolayer crystalline film can be described exquisitely by its inscribed surface. Depending on this inscribed surface of armchair carbon nanotubes, the present study shows the reason why CNTs cannot be simply considered as a thin shell with constant thickness. Application of the present model to armchair CNTs predicts that the ranges of Young's modulus and effective thickness are respectively from 2.407 to 3.209 TPa and from 0.082 to 0.073 nm, which are in good agreement with previous theoretical studies and experimental observations.
SYNTHESIS AND CHARACTERIZATION OF SPHERE-LIKE ZnS NANOCRYSTALS BY THERMOLYSIS OF A NEW COMPLEX PRECURSOR
Authors: ZHANG JIANJUN , DUAN JUNHONG
Published: July 2010

In this paper, the preparation and optical properties of sphere-like ZnS nanocrystals are reported. Pure and uniform cubic-phase sphere-like ZnS nanocrystals with grain sizes of 30–40 nm were synthesized by thermolysis of a new precursor complex ( enH 2)0.5[ Zn ( en )3]( SCN )3 (en = ethylenediamine) in nitrogen stream at 800°C. The as-synthesized products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS), respectively. The XRD analysis reveals the phase of ZnS with cubic zinc blende. UV-Vis and photoluminescence spectra (PL) were utilized to investigate the optical properties of sphere-like ZnS nanocrystals. By testing on UV-Vis spectra, it is concluded that the limiting wavelength of the ZnS nanocrystals is 320 nm and the band gap is 3.88 eV. In room temperature PL spectra, one strong emission peak centered at 322 nm is discovered, which could be attributed to the band to band transitions. The above-mentioned results showed that the thermolysis method is preferable for synthesizing high-quality sphere-like ZnS nanocrystals. The synthesized precursor could be used as morphological templates to prepare nanostructure inorganic compounds.
Characterizing Graphene, Graphite, and Carbon Nanotubes by Raman Spectroscopy
Authors: Dresselhaus M.S. , Jorio A. , Saito R.
Published: July 2010

Recent advances in Raman spectroscopy for characterizing graphene, graphite, and carbon nanotubes are reviewed comparatively. We first discuss the first-order and the double-resonance (DR) second-order Raman scattering mechanisms in graphene, which give rise to the most prominent Raman features. Then, we review phonon-softening phenomena in Raman spectra as a function of gate voltage, which is known as the Kohn anomaly. Finally, we review exciton-specific phenomena in the resonance Raman spectra of single-wall carbon nanotubes (SWNTs). Raman spectroscopy of SWNTs has been especially useful for understanding many fundamental properties of all sp2 carbons, given SWNTs can be either semiconducting or metallic depending on their geometric structure, which is denoted by two integers (n,m).
Nematic Fermi Fluids in Condensed Matter Physics
Authors: Fradkin Eduardo , Kivelson Steven A. , Lawler Michael J. , Eisenstein James P. , Mackenzie Andrew P.
Published: July 2010

Correlated electron fluids can exhibit a startling array of complex phases, among which one of the more surprising is the electron nematic, a translationally invariant metallic phase with a spontaneously generated spatial anisotropy. Classical nematics generally occur in liquids of rod-like molecules; given that electrons are point like, the initial theoretical motivation for contemplating electron nematics came from thinking of the electron fluid as a quantum melted electron crystal, rather than a strongly interacting descendent of a Fermi gas. Dramatic transport experiments in ultra-clean quantum Hall systems in 1999 and in Sr3Ru2O7in a strong magnetic field in 2007 established that such phases exist in nature. In this article, we briefly review the theoretical considerations governing nematic order, summarize the quantum Hall and Sr3Ru2O7experiments that unambiguously establish the existence of this phase, and survey some of the current evidence for such a phase in the cuprate and Fe-based high temperature superconductors.
Dynamics of Simple Cracks
Authors: Bouchbinder Eran , Fineberg Jay , Marder M.
Published: July 2010

Cracks are the major vehicle for material failure and often exhibit rather complex dynamics. The laws that govern their motion have remained an object of constant study for nearly a century. The simplest kind of dynamic crack is a single crack that moves along a straight line. We first briefly review the current understanding of this “simple” object. We then critically examine the assumptions of the classic, scale-free theory of dynamic fracture and note when it works and how it may fail if certain assumptions are relaxed. Several examples are provided in which the introduction of physical scales into this scale-free theory profoundly affects both a crack's structure and the resulting dynamics.
Friction, Fracture, and Earthquakes
Authors: Daub Eric G. , Carlson Jean M.
Published: July 2010

A primary goal in seismology is to identify constraints arising from the small-scale physics of friction and fracture that can provide bounds on seismic hazard and ground motion at the fault scale. Here, we review the multiscale earthquake rupture problem and describe a physical model for the deformation of amorphous materials such as granular fault gouge. The model is based on shear transformation zone (STZ) theory, a microscopic model for plastic deformation. STZ theory ties fault weakening to the evolution of an effective temperature, which quantifies configurational disorder and captures the spontaneous formation and growth of narrow shear bands in the fault gouge.
The Jamming Transition and the Marginally Jammed Solid
Authors: Liu Andrea J. , Nagel Sidney R.
Published: July 2010

When a system jams, it undergoes a transition from a flowing to a rigid state. Despite this important change in the dynamics, the internal structure of the system remains disordered in the solid as well as the fluid phase. In this way jamming is quite different from crystallization, the other common way in which a fluid solidifies. Jamming is a paradigm for thinking about how many different types of fluids—from molecular liquids to macroscopic granular matter—develop rigidity. Here we review recent work on the jamming transition. We start with perhaps the simplest model: frictionless spheres interacting via repulsive finite-range forces at zero temperature. In this highly idealized case, the transition has aspects of both first- and second-order transitions. From studies of the normal modes of vibration for the marginally jammed solid, new physics has emerged for how a material can be rigid without having the elastic properties of a normal solid. We first survey the simulation data and theoretical arguments that have been proposed to understand this behavior. We then review work that has systematically gone beyond the ideal model to see whether the scenario developed there is more generally applicable. This includes work that examines the effect of nonspherical particles, friction, and temperature on the excitations and the dynamics. We briefly touch on recent laboratory experiments that have begun to make contact with simulations and theory.
The Mechanics and Statistics of Active Matter
Authors: Ramaswamy Sriram
Published: July 2010

Active particles contain internal degrees of freedom with the ability to take in and dissipate energy and, in the process, execute systematic movement. Examples include all living organisms and their motile constituents such as molecular motors. This article reviews recent progress in applying the principles of nonequilibrium statistical mechanics and hydrodynamics to form a systematic theory of the behavior of collections of active particles–active matter–with only minimal regard to microscopic details. A unified view of the many kinds of active matter is presented, encompassing not only living systems but inanimate analogs. Theory and experiment are discussed side by side.
Necessity of the glossopharyngeal nerve in the maintenance of normal intake and ingestive bout size of corn oil by rats
Authors: Treesukosol Yada , Blonde Ginger D. , Jiang Enshe , Gonzalez Dani , Smith James C. , Spector Alan C.
Published: July 2010

Recent evidence in the literature suggests that signals carried by the glossopharyngeal nerve (GL), which supplies sensory and parasympathetic innervation of the posterior tongue, might be essential in the maintenance of normal gustatory responses to fat stimuli. Here, we report that GL transection (GLX) significantly decreased corn oil intake and preference in 23-h two-bottle tests relative to sham-operated controls (Sham). Drinking-pattern analysis of corn oil licking revealed that bout size, rather than the number of bouts initiated, was smaller in GLX than Sham rats. We also tested a range of glucose concentrations and found that total licks over daily 23-h sessions significantly decreased in GLX compared with Sham rats, but this difference failed to reach significance when intake or any bout parameter was measured. These results show that the signals in the GL normally contribute to processes involved with corn oil bout termination as opposed to bout initiation. GL-derived signals could potentially provide input to “reward” circuits in the ventral forebrain that could serve to maintain ingestion during a meal or, alternatively, could act at the level of the brain stem to attenuate the inhibitory potency of vagal signals, thus delaying the onset of satiation, or perhaps contribute to a cephalic phase reflex modulation of the gut. Parasympathetic efferents in the GL innervating the von Ebner's glands, which secrete lingual lipase, which is thought to break down corn oil into detectable ligands, could also be playing a role in driving corn oil intake. Whatever the mechanism, an intact GL is clearly necessary in maintaining normal intake of corn oil.
Persistent antihypertensive effect of aliskiren is accompanied by reduced proteinuria and normalization of glomerular area in Ren-2 transgenic rats
Authors: Rakušan Dan , Kujal Petr , Kramer Herbert J. , Husková Zuzana , Vaňourková Zdeňka , Vernerová Zdenka , Mrázová Iveta , Thumová Monika , Červenka Luděk , Vaněčková Ivana
Published: July 2010

The effects of the human renin inhibitor aliskiren on blood pressure (BP), end-organ damage, proteinuria, and tissue and plasma angiotensin (ANG) II levels in young and adult heterozygous Ren-2 transgenic rats (TGR) were evaluated and compared with the effect of the ANG type 1 (AT1) receptor blocker losartan during treatment and after 12 days after the withdrawal of drug treatments. BP was monitored by telemetry from the age of 32 days on (young rats) and at 100 days (adult rats). Aliskiren (10 mg·kg−1·day−1in osmotic minipumps) or losartan (5 mg·kg−1·day−1in drinking water) treatment was applied for 28 days in young rats and for 70 days in adult rats. In young untreated TGR, severe hypertension rapidly evolved. Adult untreated TGR exhibited stable established hypertension. Both aliskiren and losartan fully prevented the development of hypertension and cardiac hypertrophy in young TGR and normalized BP and cardiac hypertrophy in adult TGR. After cessation of aliskiren treatment in both young and adult TGR BP and cardiac hypertrophy were persistently reduced, while after losartan withdrawal BP and cardiac hypertrophy rapidly increased. In adult aliskiren-treated rats proteinuria was significantly reduced compared with losartan (the effect persisting after withdrawal of treatment), and this decrease strongly correlated with normalization of glomerular size in these animals. In conclusion, aliskiren and losartan had similar antihypertensive effects during chronic treatment, but the antihypertensive and organoprotective effects of aliskiren were persistent even after the 12-day washout period. The durable effect on proteinuria can possibly be attributed to the normalization of glomerular morphology.
New Oral Anticoagulants for Thromboprophylaxis after Elective Total Hip and Knee Arthroplasty
Authors: Friedman Richard J.
Published: July 2010

Anticoagulant drugs reduce the risk of venous thromboembolic events after total hip and knee arthroplasty. However, the use of current drugs, such as low molecular weight heparins, is hampered by their subcutaneous route of administration. The use of vitamin K antagonists is hampered by the requirement for routine coagulation monitoring and dose titration to provide effective anticoagulation without an increased risk of bleeding and numerous food and drug interactions. Clearly, there is a need for new oral, fixed-dose anticoagulant drugs that do not require coagulation monitoring, while demonstrating similar or better efficacy and safety profiles when compared with current agents.
The Master Space of Supersymmetric Gauge Theories
Authors: Hanany Amihay , Zaffaroni Alberto
Published: July 2010

We give a short review on the study of the moduli space and the spectrum of chiral
operators for gauge theories living on branes at singularities. We focus on theories with
four real supercharges in 3+1 and 2+1 dimensions. The theories are holographically
dual to AdS5 × H5 or AdS4 × H7 backgrounds, in Type‐IIB or ‐M theory, respectively. We demonstrate that most of the information on the moduli space and spectrum of the quiver gauge theories is encoded in the concept of the “Master Space”, which is roughly the full moduli space for one brane, consisting of mesonic and baryonic degrees of freedom. We summarize the relevant information in generating functions for chiral operators, which can be computed using plethystics techniques and the language of complex geometry.
Contribution of Gut Bacteria to Liver Pathobiology
Authors: Son Gakuhei , Kremer Michael , Hines Ian N.
Published: July 2010

Emerging evidence suggests a strong interaction between the gut microbiota and health and disease. The interactions of the gut microbiota and the liver have only recently been investigated in detail. Receiving approximately 70% of its blood supply from the intestinal venous outflow, the liver represents the first line of defense against gut-derived antigens and is equipped with a broad array of immune cells (i.e., macrophages, lymphocytes, natural killer cells, and dendritic cells) to accomplish this function. In the setting of tissue injury, whereby the liver is otherwise damaged (e.g., viral infection, toxin exposure, ischemic tissue damage, etc.), these same immune cell populations and their interactions with the infiltrating gut bacteria likely contribute to and promote these pathologies. The following paper will highlight recent studies investigating the relationship between the gut microbiota, liver biology, and pathobiology. Defining these connections will likely provide new targets for therapy or prevention of a wide variety of acute and chronic liver pathologies.
Molecular and Therapeutic Potential and Toxicity of Valproic Acid
Authors: Chateauvieux Sébastien , Morceau Franck , Dicato Mario , Diederich Marc
Published: July 2010

Valproic acid (VPA), a branched short-chain fatty acid, is widely used as an antiepileptic drug and a mood stabilizer. Antiepileptic properties have been attributed to inhibition of Gamma Amino Butyrate (GABA) transaminobutyrate and of ion channels. VPA was recently classified among the Histone Deacetylase Inhibitors, acting directly at the level of gene transcription by inhibiting histone deacetylation and making transcription sites more accessible. VPA is a widely used drug, particularly for children suffering from epilepsy. Due to the increasing number of clinical trials involving VPA, and interesting results obtained, this molecule will be implicated in an increasing number of therapies. However side effects of VPA are substantially described in the literature whereas they are poorly discussed in articles focusing on its therapeutic use. This paper aims to give an overview of the different clinical-trials involving VPA and its side effects encountered during treatment as well as its molecular properties.
Adhesion on Nanoorganized Multilayers: Surface Thermodynamics and Local Energy Dissipation
Authors: Kazzi Yolla , Awada Houssein , Nardin Michel
Published: July 2010

Nanostructured multilayers, composed of alternate organic (3-mercaptopropyltrimethoxysilane, alkylthiols, polydimethylsiloxane) and metallic (gold) layers, are grafted onto glass and prepared in order to modify the mechanical and dissipative properties of a thin surface layer of the substrate. The external face is constituted either of gold or alkyl groups, allowing us to study two types of surfaces exhibiting different chemical and thermodynamic properties. The formation and the structure of the nanostructured multilayers are first examined by means of various techniques such as atomic force microscopy (AFM), wettability, X-ray photoelectron spectroscopy (XPS), and conductivity measurements. All the results concerning the structure of the systems studied are used to understand the adhesive properties at short contact times (tack) of the multi-layers and an elastomer (polyisoprene). The influence of the structural aspects of gold layers, the length of the alkyl chains of the top layer, the terminal functionality, and the length of the confined organic layer between two gold layers on the energy of adhesion regarding the polyisoprene are clearly demonstrated. The influence of the nano-structured surface layers on adhesion phenomena is explained in terms of either the surface thermodynamics or local energy dissipation during the propagation of a fracture according to complex mechanisms.
Portfolio Selection with Jumps under Regime Switching
Authors: Zhao Lin
Published: July 2010

We investigate a continuous‐time version of the mean‐variance portfolio selection model with jumps under regime switching. The portfolio selection is proposed and analyzed for a market consisting of one bank account and multiple stocks. The random regime switching is assumed to be independent of the underlying Brownian motion and jump processes. A Markov chain modulated diffusion formulation is employed to model the problem.
The Role of Adipokines in Understanding the Associations between Obesity and Depression
Authors: Taylor Valerie H. , MacQueen Glenda M.
Published: July 2010

Objective. Two major causes of disability, major depression and obesity, share overlapping psychosocial and pathophysiological etiologies. Studies are now focused on biological mechanisms linking the two illnesses, and there is interest in the role that adipokines may have in mediating the association between obesity and depression. We reviewed the literature to look at what is currently known about this association, focusing on the adipokines leptin, adiponectin, and resistin.Methods. A MEDLINE search, citing articles from 1966 onward, supplemented by a review of bibliographies, was conducted to identify relevant studies.Results. This paper identified plausible pathways underlying a link between adipokines and depression. Only a few studies have yet been conducted specifically examining these biomarkers in patients with depression, but the results are intriguing.Conclusion. This paper is one of the first to examine the association between adipokines and depression. It provides an overview of the physiological role of adipokines and summarizes the data suggesting that they may be dysregulated in major depression. This area of research may become increasingly important as new treatment strategies are developed.
Oncogenic Wip1 Phosphatase Is Inhibited by miR-16 in the DNA Damage Signaling Pathway
Authors: Zhang Xinna , Wan Guohui , Mlotshwa Sizolwenkosi , Vance Vicki , Berger Franklin G. , Chen Hexin , Lu Xiongbin
Published: July 2010

Wild-type p53-induced phosphatase 1 (Wip1) was identified as an oncogene amplified and overexpressed in several human cancers. Recent evidence suggested that Wip1 is a critical inhibitor in the ATM/ATR-p53 DNA damage signaling pathway. Wip1 dephosphorylates several key DNA damage–responsive proteins and reverses DNA damage–induced cell cycle checkpoints. Previous reports showed that Wip1 was transcriptionally induced by p53 at the early stage of the DNA damage response. To investigate the temporal and functional regulation of Wip1, we identified a microRNA, miR-16, that specifically targets the mRNA of Wip1 and thus negatively regulates the expression level of Wip1. miR-16 itself is induced immediately after DNA damage. Therefore, the increase in Wip1 protein level is significantly postponed compared with that of its mRNA level, preventing a premature inactivation of ATM/ATR signaling and allowing a functional completion of the early DNA damage response. To better understand miR-16 biological functions in the context of cancer cells, we examined its expression in mammary tumor stem cells and found it to be markedly downregulated in mammary tumor stem cells. Overexpression of miR-16 or inhibition of Wip1 suppresses the self-renewal and growth of mouse mammary tumor stem cells and sensitizes MCF-7 human breast cancer cells to the chemotherapeutic drug doxorubicin. Together, our results suggest an important role of miR-16 in the regulation of Wip1 phosphatase in the DNA damage response and mammary tumorigenesis. Cancer Res; 70(18); 7176–86. ©2010 AACR.
Retrograde Single Stapling Technique for Laparoscopic Ultralow Anterior Resection
Authors: Kawahara Hidejiro , Watanabe Kazuhiro , Ushigome Takuro , Noaki Rohta , Kobayashi Susumu , Yanaga Katsuhiko
Published: July 2010

A highly effective surgical technique is required for laparoscopic low rectal transection without sufficient distal margins when ultralow anterior resection (ULAR) with a stapler is a technical challenge for laparoscopic surgery. We report a retrograde single stapling technique (RSST) for laparoscopic ULAR. Total mesorectal excision is performed laparoscopically. After the anal side of the tumor has been closed transanally, the distal line in the right lateral wall of the rectum is partially transected with laparoscopic coagulation shears (LCS). The distal line in the rectum is transected circularly with LCS after detecting the cutting part in the right lateral wall of the rectum laparoscopically. The end of the distal rectum is closed by a purse-string suture using 2-0 prolene transanally. Intestinal resection is performed extracorporeally through a suprapubic incision. After an anvil is placed in the proximal end of the colon over a purse-string suture, it is introduced to the anal canal transabdominally. The purse-string suture is tied to the anvil shaft before connecting it to the center shaft of the circular stapler; the instrument is then fired to create end-to-end anastomosis. For the prevention of anastomotic leakage, a 24-french balloon catheter which decompresses the anastomosis is inserted through the anus.
Transoral Robotic Surgery of the Skull Base: A Cadaver and Feasibility Study
Authors: Lee John Y.K. , O’Malley, Jr. Bert W. , Newman Jason G. , Weinstein Gregory S. , Lega Bradley , Diaz Jason , Grady M. Sean
Published: July 2010

Objective: The goal of this study was to determine the potential role as well as the current limitations of the da Vinci Surgical System robot in transoral surgery of the skull base. Methods: The da Vinci robot was used to perform dissections of the skull base on 7 cadaver heads with their neck and clavicles intact. Neurosurgeons and otolaryngologists familiar with all facets of the open microscopic, minimally invasive, endoscopic and transoral robotic surgical procedure proceeded with the approach to and dissection of the human skull base. Results: The da Vinci robot provided superb illumination and 3-dimensional depth perception. The 30- degree endoscope improved cephalad visualization, and the ‘intuitive’ nature of the da Vinci surgical robot arms provided an advantage by their ability to suture the dura at the level of the clivus. An entirely transoral route provides access to the middle and lower clivus as well as the infratemporal fossa, but access to the sellar region and anterior cranial fossa is limited via a purely transoral route. Tremor-free dural closure was successfully performed. Conclusion: Our findings suggest that transoral robotic surgery utilizing the da Vinci robot system holds great potential for skull base surgical resection of extradural and intradural tumors of the middle and lower clivus and infratemporal fossa. A collaborative approach with neurosurgeon and otolaryngologist alternating at the master console and bedside is a successful strategy. Further instrument development is necessary, and continued investigation is warranted.
A Novel Technique for the Management of Pancreaticojejunal Anastomosis Dehiscence following Pancreaticoduodenectomy
Authors: Bu Xianmin , Xu Jin , Dai Xianwei
Published: July 2010

Background: To report a novel technique for management of pancreaticojejunal anastomosis dehiscence after pancreaticoduodenectomy. Material and Methods: The anastomosis is disconnected and the blind jejunal limb is shortened and closed. A silicon tube in the pancreatic duct introduced in the first operation is fixed at the pancreatic stump. If no tube was placed during pancreaticoduodenectomy, it is placed at reoperation. The transected edge of the pancreas is stitched, and the distal part of the silicon tube is inserted into the jejunal loop and fixed in the jejunal wall. Drains and a catheter for continuous irrigation are placed. Results: All patients tolerated reoperation and experienced unremarkable postoperative courses. Follow-up ranged from 5 to 27 months, and all patients exhibited normal pancreatic function and no pseudocyst formation. Conclusion: This technique is an effective method for management of pancreaticojejunal anastomosis dehiscence that avoids complications associated with completion pancreatectomy and preserves pancreatic function.
Postrelease Success of Two Rehabilitated Vervet Monkey (Chlorocebus aethiops) Troops in KwaZulu-Natal, South Africa
Authors: Wimberger Kirsten , Downs Colleen T. , Perrin Michael R.
Published: July 2010

In South Africa, the most common primate in rehabilitation centres is the vervet monkey (Chlorocebus aethiops). Here we evaluated the efficacy of releasing two vervet monkey troops into the wild, using the standard methods employed by an established rehabilitation centre. Two troops were assembled over 2–3 years. Coloured ear tags identified adults, subadults and juveniles. Radiocollars were placed on all the adults and subadults of both troops (41% of all individuals). Each troop was released at a suitable site after 2 nights in a holding cage, and supplementary food was provided for 2 months after release. For 10 months, locations of both troops were recorded, as well as the presence/absence of individuals and their general behaviour. The smaller troop survived better than the larger troop, with only 6 of 35 individuals (17%) confirmed alive in the large troop compared with 12 of 24 (50%) in the small troop. Large numbers of missing monkeys make it difficult to determine whether the release was a success. However, results suggest that rehabilitated vervet monkeys could be successfully released in the future. Recommendations are provided for consideration in future releases.