bluuebunny/crossref_metadata_2025 huggingface dataset:
Dipeptidyl‐peptidase IV inhibitor is effective in patients with type 2 diabetes with high serum eicosapentaenoic acid concentrations
Authors: Senmaru Takafumi , Fukui Michiaki , Kobayashi Kanae , Iwase Hiroya , Inada Shinobu , Okada Hiroshi , Asano Mai , Yamazaki Masahiro , Hasegawa Goji , Nakamura Naoto , Iwasaki Masahiro , Yabe Daisuke , Kurose Takeshi , Seino Yutaka
Published: May 2012

Aims/Introduction:  Eicosapentaenoic acid (EPA) stimulates glucagon‐like peptide‐1 (GLP‐1) secretion in mice. We investigated the relationship between serum EPA concentrations and the efficacy of dipeptidyl‐peptidase IV (DPP‐4) inhibitor in patients with type 2 diabetes.

Materials and Methods:  Serum EPA concentrations were measured in 62 consecutive patients with type 2 diabetes who were newly given DPP‐4 inhibitor as a monotherapy or as an add‐on therapy to oral hypoglycemic agents. The dosage of oral hypoglycemic agents was maintained during the observation period. After 24 weeks of treatment with DPP‐4 inhibitor, we evaluated the relationships between a decrease in hemoglobin A1c from baseline and serum EPA concentrations, as well as age, sex, body mass index (BMI), hemoglobin A1c at baseline and usage of antidiabetic concomitant drugs.

Results:  Hemoglobin A1c was significantly decreased from 8.1 ± 1.1% to 7.2 ± 1.0% by DPP‐4 inhibitor. A decrease in hemoglobin A1c correlated with BMI (r = −0.396, P = 0.0013), age (r = 0.275, P = 0.0032), hemoglobin A1c at baseline (r = 0.490, P < 0.0001) and log EPA (r = 0.285, P = 0.0246). Multiple regression analysis showed that BMI (β = −0.419, P = 0.0002), hemoglobin A1c at baseline (β = 0.579, P < 0.0001) and log EPA (β = 0.220, P = 0.0228) were independent determinants of decrease in hemoglobin A1c.

Conclusions:  DPP‐4 inhibitor is effective in patients with type 2 diabetes with high serum EPA concentrations. (J Diabetes Invest, doi: 10.1111/j.2040‐1124.2012.00220.x , 2012)
Comparison of blood pressure and sympathetic activity of rabbits in their home cage and the laboratory environment
Authors: Lim Kyungjoon , Burke Sandra L. , Armitage James A. , Head Geoffrey A.
Published: May 2012

Methodological improvements in measuring cardiovascular parameters have meant that data can be collected from freely moving animals in their home cage. However, experiments in rabbits still often require them to be restrained in a laboratory setting. The aim of this study was to determine whether measurements collected when rabbits were placed in a holding box in the laboratory are representative of values obtained in freely moving conscious rabbits. Nine New Zealand White rabbits received two radiotelemetry implants to monitor mean arterial pressure (MAP) and renal sympathetic nerve activity (RSNA). The MAP measured in the laboratory (71 ± 1 mmHg) was similar to that in the home cage (69 ± 1 mmHg), but there was less MAP variability. The RSNA was also similar in both environments. In contrast, laboratory heart rate (HR) was 7% lower than home cage HR (181 ± 4 beats min−1, P < 0.001), but HR variability was similar. Baroreflex gain, assessed by spectral analysis, was 19% higher in the laboratory than in the home cage due to lower MAP mid‐frequency variability in the laboratory. Home cage circadian patterns of MAP and HR were strongly influenced by feeding and activity. Nevertheless, MAP and RSNA laboratory measurements were the same as average 24 h values and remained similar over several weeks. We conclude that while HR is generally lower in the laboratory, a valid representation of MAP and RSNA can be given by laboratory measurements.
Control of breathing and blood pressure by parafacial neurons in conscious rats
Authors: Takakura Ana C. , Moreira Thiago S. , De Paula Patrícia M. , Menani José V. , Colombari Eduardo
Published: May 2012

New Findings

What is the central question of this study?

The main purpose of the present manuscript was to investigate the cardiorespiratory responses to hypoxia or hypercapnia in conscious rats submitted to neuronal blockade of the parafacial region. We clearly showed that the integrity of parafacial region is important for the respiratory responses elicited by peripheral and central chemoreflex activation in freely behavior rats.

What is the main finding and its importance?

Since the parafacial region is part of the respiratory rhythm generator, they are essential for postnatal survival, which is probably due to their contribution to chemoreception in conscious rats.

The retrotrapezoid nucleus (RTN), located in the parafacial region, contains glutamatergic neurons that express the transcriptor factor Phox2b and that are suggested to be central respiratory chemoreceptors. Studies in anaesthetized animals or in vitro have suggested that RTN neurons are important in the control of breathing by influencing respiratory rate, inspiratory amplitude and active expiration. However, the contribution of these neurons to cardiorespiratory control in conscious rats is not clear. Male Holtzman rats (280–300 g, n= 6–8) with bilateral stainless‐steel cannulae implanted into the RTN were used. In conscious rats, the microinjection of the ionotropic glutamatergic agonist NMDA (5 pmol in 50 nl) into the RTN increased respiratory frequency (by 42%), tidal volume (by 21%), ventilation (by 68%), peak expiratory flow (by 24%) and mean arterial pressure (MAP, increased by 16 ± 4, versus saline, 3 ± 2 mmHg). Bilateral inhibition of the RTN neurons with the GABAA agonist muscimol (100 pmol in 50 nl) reduced resting ventilation (52 ± 34, versus saline, 250 ± 56 ml min−1 kg−1 with absolute values) and attenuated the respiratory response to hypercapnia and hypoxia. Muscimol injected into the RTN slightly reduced resting MAP (decreased by 13 ± 7, versus saline, increased by 3 ± 2 mmHg), without changing the effects of hypercapnia or hypoxia on MAP and heart rate. The results suggest that RTN neurons activate facilitatory mechanisms important to the control of ventilation in resting, hypoxic or hypercapnic conditions in conscious rats.
Altered cortical activation patterns associated with baroreflex unloading following 24 h of physical deconditioning
Authors: Shoemaker J. K. , Usselman C. W. , Rothwell A. , Wong S. W.
Published: May 2012

Cardiovascular arousal is associated with patterned cortical activity changes. Head‐down‐tilt bed rest (HDBR) dimishes the baroreflex‐mediated cardiac control. The present study tested the hypothesis that HDBR deconditioning would modify the forebrain organization for heart rate (HR) control during baroreflex unloading. Heart rate variability (HRV), blood pressure and plasma hormones were analysed at rest, whereas HR and cortical autonomic activation patterns (functional magnetic resonance imaging) were measured during graded and randomly assigned lower body negative pressure treatments (LBNP, −15 and −35 mmHg) both before (Pre) and after (Post) a 24 h HDBR protocol (study 1; n= 8). An additional group was tested before and following diuretic‐induced hypovolaemia (study 2; n= 9; spironolactone, 100 mg day–1 for 3 days) that mimicked the plasma volume lost during HDBR (−15% in both studies; P < 0.05). Head‐down bed rest with hypovolaemia did not affect baseline HR, mean arterial pressure, HRV or plasma catecholamines. Head‐down bed rest augmented the LBNP‐induced HR response (P < 0.05), and this was associated with bed‐rest‐induced development of the following changes: (i) enhanced activation within the genual anterior cingulate cortex and the right anterior insular cortex; and (ii) deactivation patterns within the subgenual regions of the anterior cingulate cortex. Diuretic treatment (without HDBR) did not affect baseline HR and mean arterial pressure, but did reduce resting HRV and elevated circulating noradrenaline and plasma renin activity (P < 0.05). The greater HR response to LBNP following diuretic (P < 0.05) was associated with diminished activation of the right anterior insula. Our findings indicate that 24 h of HDBR minimized the impact of diuretic treatment on baseline autonomic and cardiovascular variables. The findings also indicate that despite the similar augmentation of HR responses to LBNP and despite similar pre‐intervention cortical activation patterns, HDBR and diuretic treatment produced different effects on the cortical responses, with HDBR affecting anterior cingulate cortex and right insula regions, whereas diuretic treatment affected primarily the right insula alone, but in a direction that was opposite to HDBR. The data indicate that physical deconditioning can induce rapid functional changes within the cortical circuitry associated with baroreflex unloading, changes that are distinct from diuretic‐induced hypovolaemia. The results suggest that physical activity patterns exert a rapid and notable impact on the cortical circuitry associated with cardiovascular control.
Quantification of the Impact of Embedded Graphite Nanofibers on the Transient Thermal Response of Paraffin Phase Change Material Exposed to High Heat Fluxes
Authors: Chintakrinda Kireeti , Warzoha Ronald J. , Weinstein Randy D. , Fleischer Amy S.
Published: May 2012

Paraffin phase change material (PCM) is enhanced with suspended graphite nanofibers at high loading levels. The loading levels reach in excess of 10% by weight. The thermal effects of the nanofiber loading level, the PCM module design, and the applied power density on the transient thermal response of the system are examined. A strong effect of nanofiber loading level on thermal performance is found, including a suppression of Rayleigh-Benard convection currents at high loading levels. Increases in nanofiber loading level also result in lowered heating rates and greater thermal control of the heated base. Increases in power density are found to result in higher heating rates, and increases in mass lead to lower operating temperatures. The design of the module is found to have a strong effect on thermal performance.
Prediction of Turbulent Heat Transfer in Rotating and Nonrotating Channels With Wall Suction and Blowing
Authors: Younis B. A. , Weigand B. , Laqua A.
Published: May 2012

This paper reports on the prediction of heat transfer in a fully developed turbulent flow in a straight rotating channel with blowing and suction through opposite walls. The channel is rotated about its spanwise axis; a mode of rotation that amplifies the turbulent activity on one wall and suppresses it on the opposite wall leading to reverse transition at high rotation rates. The present predictions are based on the solution of the Reynolds-averaged forms of the governing equations using a second-order accurate finite-volume formulation. The effects of turbulence on momentum transport were accounted for by using a differential Reynolds-stress transport closure. A number of alternative formulations for the difficult fluctuating pressure–strain correlations term were assessed. These included a high turbulence Reynolds-number formulation that required a “wall-function” to bridge the near-wall region as well as three alternative low Reynolds-number formulations that permitted integration through the viscous sublayer, directly to the walls. The models were assessed by comparisons with experimental data for flows in channels at Reynolds-numbers spanning the range of laminar, transitional, and turbulent regimes. The turbulent heat fluxes were modeled via two very different approaches: one involved the solution of a modeled differential transport equation for each of the three heat-flux components, while in the other, the heat fluxes were obtained from an explicit algebraic model derived from tensor representation theory. The results for rotating channels with wall suction and blowing show that the algebraic model, when properly extended to incorporate the effects of rotation, yields results that are essentially identically to those obtained with the far more complex and computationally intensive heat-flux transport closure. This outcome argues in favor of incorporation of the algebraic model in industry-standard turbomachinery codes.
Heat Transfer Across Opaque Fibers
Authors: Manohar Krishpersad , Kochhar Gurmohan S. , Yarbrough David W.
Published: May 2012

Predicting the thermal conductivity of loose-fill fibrous thermal insulation is a complex problem, when considering the combined conduction, convection, and radiation heat transfer within a scattering, emitting, and absorbing medium. A piecewise model for predicting the overall apparent thermal conductivity of large diameter opaque fibrous materials was developed by considering the radiation heat transfer, solid conduction and air conduction components separately. The model utilized the physical parameters of emissivity, the density of the solid fiber material, the percentage composition and range of fiber diameter, and the mean fiber diameter to develop specific equations for piecewise contribution from radiation, solid fiber conduction, and air conduction toward the overall effective thermal conductivity. It can be used to predict the overall apparent thermal conductivity for any opaque fibrous specimen of density (ρ), known thickness (t), mean temperature (T), and temperature gradient (ΔΤ). Thermal conductivity measurements were conducted in accordance with ASTM C518 specifications on 52 mm thick, 254 mm square test specimens for coconut and sugarcane fibers. The test apparatus provided results with an accuracy of 1%, repeatability of 0.2%, and reproducibility of 0.5%. The model was applied to and compared with experimental data for coconut and sugarcane fiber specimens and predicted the apparent thermal conductivity within 7% of experimental data over the density range tested. The model also predicted the optimum density range for both coconut and sugarcane fibers.
Heat and Fluid Flow Around a Sphere With Cylindrical Bore
Authors: Richter Andreas , Nikrityuk Petr A.
Published: May 2012

This work is devoted to the numerical investigation of heat and fluid flow past a sphere with a centric, cylindrical bore. Such spherical rings are of interest in many technological processes. In chemical reactors, for example, spherical rings are used as a catalyst with an increased reacting surface. Motivated by this fact, we considered spherical rings with different bores and different orientations in flow regimes corresponding to Reynolds numbers from 10 up to 300. The results show a significant influence of the bore diameter on the symmetry and hence the steadiness of the flow field. The Nusselt number can be increased, which leads to a moderate rise in the drag coefficient. Thereby, the effect of the borehole depends on the Reynolds number, the bore diameter, and the angle of attack. For that reason, drag forces and total heat transfers do not simply follow the heat exchanging surface area. Based on the presented results, new correlations are given for both the drag coefficient and the Nusselt number; correlations which incorporate the bore geometry and the bore orientation in the flow field.
Optical Analysis of the Fixed Mirror Solar Concentrator by Forward Ray-Tracing Procedure
Authors: Pujol Nadal Ramon , Martínez Moll Víctor
Published: May 2012

The fixed mirror solar concentrator (FMSC) is a mobile focus concentrator whose design emerged in the 1970s in an effort to reduce electricity production costs in solar thermal power plants. This geometry has not yet been analyzed with 3D ray-tracing procedures. The geometry of FMSC is defined using three parameters: the number of mirrors N, the ratio of focal length and reflector width F/W, and the intercept factor γ (in order to represent different receiver widths). For the analysis, a 3D ray-tracing code that allows the characterization of solar concentrators was developed. A standard evacuated tube was used as a receiver. The geometric concentration ratio, the optical efficiency, and the transversal and longitudinal incidence angle modifier (IAM) curves for different values of design parameters were calculated. High concentrations imply low F/W values and for high efficiencies, large intercept factor values are required. Increasing the F/W ratio has a positive effect on the transversal IAM, yet a negative one for the longitudinal IAM. Increasing the number of mirrors has a negative effect on both IAM curves due to the self-shadowing between the adjacent steps. Increasing the intercept factor only has a significant positive effect on the longitudinal IAM. The goodness of the IAM factorization approach was analyzed, and it was found that it can be used as long as a new correction factor to account for the focus displacement is introduced. The results presented in this paper provide information, in form of curves, regarding the optical behavior of the FMSC in terms of different design parameters in order to know the possibility to use the FMSC in medium range temperature applications.
An Omnidirectional Rolling 8U Parallel Mechanism
Authors: Liu Chang-huan , Li Rui-ming , Yao Yan-an
Published: May 2012

A novel 8U (universal joint) parallel mechanism, being able to do omnidirectional rolling motion is proposed in this paper. This mobile mechanism owns the priority of simple structure and rolling easily on terrains with loose soil, dirt or sand with only a few actuations. Its spatial closed compact structure is described firstly. In addition, the omnidirectional locomotion accompanied with DOF (degree of freedom) alternation between one and two is revealed by mobility analysis. After that, the feasibility of rolling motion is verified theoretically by stability analysis. Finally, the omnidirectinoal rolling motion is testified both by virtual and prototype experiments.
Friction and Thermal Characteristics of Laminar Flow of Viscous Oil Through a Circular Tube Having Axial Corrugations and Fitted With Helical Screw-Tape Inserts
Authors: Saha Sujoy Kumar , Swain Bikram Narayan , Dayanidhi G. L.
Published: May 2012

The experimental friction factor and Nusselt number data for a laminar flow through a circular duct having axial corrugation and fitted with helical screw-tape inserts have been presented. Predictive friction factor and Nusselt number correlations have also been presented. The thermohydraulic performance has been evaluated. The major findings of this experimental investigation are that the helical screw-tape inserts, in combination with axial corrugation, perform better than the individual enhancement technique acting alone for laminar flow through a circular duct.
Variation in band offsets at ZnO/Sn:In2O3 heterojunctions measured by x-ray photoelectron spectroscopy
Authors: Kaspar Tiffany C. , Droubay Tim C.
Published: May 2012

ZnO/Sn:In2O3 (ITO) heterojunctions were fabricated by pulsed laser deposition. Ex situ x-ray photoelectron spectroscopy (XPS) was utilized to examine the band structure and band alignments of ITO films and ZnO/ITO heterojunctions. The apparent bandgap of ITO films was found to be sensitive to oxygen plasma exposure, with an observed bandgap ∼3 eV. Type II band alignments were found for oxygen plasma treated ZnO/ITO heterojunctions with either pure ZnO, Al:ZnO, or Ga:ZnO overlayers. The conduction band offsets were in the range of −0.5 to −0.7 eV, which is a larger magnitude than desired for efficient devices. A strong effect of processing treatment, either exposure to the oxygen plasma or gentle heating in vacuum, was found for the band alignments; under some conditions, the conduction band offset reversed sign. Tuning of the processing parameters in photovoltaic or electronic devices may lead to an improvement in the ZnO/ITO alignment.
Optimization of the ammonium sulfide (NH4)2S passivation process on InSb(111)A
Authors: Zhernokletov Dmitry M. , Dong Hong , Brennan Barry , Kim Jiyoung , Wallace Robert M.
Published: May 2012

The passivation of the InSb semiconductor surface and related alloys is of interest due to their small bandgaps and high bulk mobilities, which make them favorable materials for use in quantum-well transistors and long wavelength optoelectronic devices. One of the most common passivation approaches is an ammonium sulfide ((NH4)2S) treatment; however, there are variations in the reported processing conditions for this procedure. This study represents a broad review of the different sulfur treatment parameters used as well as determining the optimal processing parameters in terms of length of time the sample is in the solution and the (NH4)2S concentration, by measuring the level of the residual native oxides, and surface roughness, by means of x-ray photoelectron spectroscopy and atomic force microscopy, respectively.
2D ordered arrays of nanopatterns fabricated by using colloidal crystals as templates
Authors: Wang Benzhong , Han Mingyong , Jin Chua Soo
Published: May 2012

A facile approach to fabricate two-dimensional (2D) ordered arrays of nanostructures is described in this paper. The approach uses spin-coating liquid materials onto a monolayer or multilayer colloidal crystal template to form a uniform film containing the template. After solidifying, the film is partially etched to expose the template which is then removed by selective etching. The fabrication procedure can produce large-area, size-tunable, periodic nanostructures with excellent structural uniformity. Large-area silica nanostructures with P6 mm symmetry have been formed by employing a dry etching technique. Experimental and simulating results also show that unique 2D nanostructures, with the feature size being much smaller than the diameter of the spherical particles used, can be obtained through three-dimensional silica nanopatterns, acted as a mask, and formed by a bilayer or trilayer colloidal crystal template.
Online database of clinical MR and ultrasound images of brain tumors
Authors: Mercier Laurence , Del Maestro Rolando F. , Petrecca Kevin , Araujo David , Haegelen Claire , Collins D. Louis
Published: May 2012

Purpose:

One of the important challenges in the field of medical imaging is finding real clinical images with which to validate new image processing algorithms. This is particularly true for tracked 3D ultrasound images of the brain.

Methods:

In 2010, pre‐ and postoperative magnetic resonance and intraoperative ultrasound images were acquired from brain tumor patients involved in the authors' imaging study at the Montreal Neurological Institute.

Results:

These data are available online at the Montreal Neurological Institute's Brain Images of Tumors for Evaluation database, termed here the MNI BITE database. It contains ultrasound and magnetic resonance images from 14 patients. Each patient underwent a preoperative and a postoperative T1‐weighted magnetic resonance scan with gadolinium enhancement, and multiple intraoperative B‐mode images were acquired before and after resection. Corresponding features were manually selected in some image pairs for validation. All images are in MINC format, the file format used at the authors' institute for image processing. The MINC tools are available for free download at packages.bic.mni.mcgill.ca.

Conclusions:

This is the first online database of its kind. These images can be used by image processing scientists as well as clinicians wishing to compare findings from magnetic resonance and ultrasound imaging.
Development of an automated region of interest selection method for 3D surface monitoring of head motion
Authors: Kang H. J. , Grelewicz Z. , Wiersma R. D.
Published: May 2012

Purpose:

To simplify the often complex and user‐dependent manual region of interest (ROI) selection process for head motion monitoring, an automatic ROI selection method was developed.

Methods:

The automatic ROI selection algorithm calculated the displacements and velocities of 3D surface points between a temporally correlated 3D image series and a reference image. Only facial surfaces satisfying certain spatial and temporal criteria were selected. The algorithm was tested on five healthy volunteers instructed to perform different types of facial movements for a total of 27 real‐time image sets (40–120 images for each image set).

Results:

The algorithm detected and excluded surface areas affected by different types of local facial movements that were independent of actual net head motion. Eye, eyebrow, and mandible motion were most commonly detected as being independent of head motion and were excluded from the final ROI. For 3D images taken with substantial facial or whole head motion, either most of the facial area was excluded or only small areas with random patterns were included in the final ROI. Surface image registration using iterative closest point (ICP) methods showed more stable real‐time head tracking using the automatically selected ROI than manual user defined ROIs.

Conclusions:

The automatic selection method successfully found ROIs stable over time for tracking head motion by excluding locally varying facial motions. By automating the ROI selection process, it is feasible that the time and complexity of current ROI definition can be reduced, together with user‐dependent registration errors.
Voxel‐wise uncertainty in CT substitute derived from MRI
Authors: Johansson Adam , Karlsson Mikael , Yu Jun , Asklund Thomas , Nyholm Tufve
Published: May 2012

Purpose:

In an earlier work, we demonstrated that substitutes for CT images can be derived from MR images using ultrashort echo time (UTE) sequences, conventional T2 weighted sequences, and Gaussian mixture regression (GMR). In this study, we extend this work by analyzing the uncertainties associated with the GMR model and the information contributions from the individual imaging sequences.

Methods:

An analytical expression for the voxel‐wise conditional expected absolute deviation (EAD) in substitute CT (s‐CT) images was derived. The expression depends only on MR images and can thus be calculated along with each s‐CT image. The uncertainty measure was evaluated by comparing the EAD to the true mean absolute prediction deviation (MAPD) between the s‐CT and CT images for 14 patients. Further, the influence of the different MR images included in the GMR model on the generated s‐CTs was investigated by removing one or more images and evaluating the MAPD for a spectrum of predicted radiological densities.

Results:

The largest EAD was predicted at air‐soft tissue and bone‐soft tissue interfaces. The EAD agreed with the MAPD in both these regions and in regions with lower EADs, such as the brain. Two of the MR images included in the GMR model were found to be mutually redundant for the purpose of s‐CT generation.

Conclusions:

The presented uncertainty estimation method accurately predicts the voxel‐wise MAPD in s‐CT images. Also, the non‐UTE sequence previously used in the model was found to be redundant.
Syndecan Teams Up with Notch
Authors: Andrianantoandro Ernesto
Published: May 2012

Syndecan-2 enhancement of Notch signaling in smooth muscle cells may play a role in angiogenesis.
Fur-Regulated Iron Uptake System of Edwardsiella ictaluri and Its Influence on Pathogenesis and Immunogenicity in the Catfish Host
Authors: Santander Javier , Golden Greg , Wanda Soo-Young , Curtiss Roy
Published: May 2012

The ability of bacterial pathogens to take up iron from the host during infection is necessary for their multiplication within the host. However, host high-affinity iron binding proteins limit levels of free iron in fluids and tissues. To overcome this deficiency of iron during infection, bacterial pathogens have developed iron uptake systems that are upregulated in the absence of iron, typically tightly controlled by the ferric uptake regulator (Fur) protein. The iron uptake system of
Edwardsiella ictaluri
, a host-restricted pathogen of channel catfish (
Ictalurus punctatus
) and the main pathogen of this fish in aquaculture, is unknown. Here we describe the
E. ictaluri
Fur protein, the iron uptake machinery controlled by Fur, and the effects of
fur
gene deletion on virulence and immunogenicity in the fish host. Analysis of the
E. ictaluri
Fur protein shows that it lacks the N-terminal region found in the majority of pathogen-encoded Fur proteins. However, it is fully functional in regulated genes encoding iron uptake proteins.
E. ictaluri
grown under iron-limited conditions upregulates an outer membrane protein (HemR) that shows heme-hemoglobin transport activity and is tightly regulated by Fur.
In vivo
studies showed that an
E. ictaluri
Δ
fur
mutant is attenuated and immune protective in zebrafish (
Danio rerio
) and catfish (
Ictalurus punctatus
), triggering systemic immunity. We conclude that an
E. ictaluri
Δ
fur
mutant could be an effective component of an immersion-oral vaccine for the catfish industry.
Design of Meningococcal Factor H Binding Protein Mutant Vaccines That Do Not Bind Human Complement Factor H
Authors: Pajon Rolando , Beernink Peter T. , Granoff Dan M.
Published: May 2012

Meningococcal factor H binding protein (fHbp) is a human species-specific ligand for the complement regulator, factor H (fH). In recent studies, fHbp vaccines in which arginine at position 41 was replaced by serine (R41S) had impaired fH binding. The mutant vaccines elicited bactericidal responses in human fH transgenic mice superior to those elicited by control fHbp vaccines that bound human fH. Based on sequence similarity, fHbp has been classified into three variant groups. Here we report that although R41 is present in fHbp from variant groups 1 and 2, the R41S substitution eliminated fH binding only in variant group 1 proteins. To identify mutants in variant group 2 with impaired fH binding, we generated fHbp structural models and predicted 63 residues influencing fH binding. From these, we created 11 mutants with one or two amino acid substitutions in a variant group 2 protein and identified six that decreased fH binding. Three of these six mutants retained conformational epitopes recognized by all six anti-fHbp monoclonal antibodies (MAbs) tested and elicited serum complement-mediated bactericidal antibody titers in wild-type mice that were not significantly different from those obtained with the control vaccine. Thus, fHbp amino acid residues that affect human fH binding differ across variant groups. This result suggests that fHbp sequence variation induced by immune selection also affects fH binding motifs via coevolution. The three new fHbp mutants from variant group 2, which do not bind human fH, retained important epitopes for eliciting bactericidal antibodies and may be promising vaccine candidates.
The
Clostridium difficile spo0A
Gene Is a Persistence and Transmission Factor
Authors: Deakin Laura J. , Clare Simon , Fagan Robert P. , Dawson Lisa F. , Pickard Derek J. , West Michael R. , Wren Brendan W. , Fairweather Neil F. , Dougan Gordon , Lawley Trevor D.
Published: May 2012

Clostridium difficile
is a major cause of chronic antibiotic-associated diarrhea and a significant health care-associated pathogen that forms highly resistant and infectious spores. Spo0A is a highly conserved transcriptional regulator that plays a key role in initiating sporulation in
Bacillus
and
Clostridium
species. Here, we use a murine model to study the role of the
C. difficile spo0A
gene during infection and transmission. We demonstrate that
C. difficile spo0A
mutant derivatives can cause intestinal disease but are unable to persist within and effectively transmit between mice. Thus, the
C. difficile
Spo0A protein plays a key role in persistent infection, including recurrence and host-to-host transmission in mice.
Role of Mouse Peptidoglycan Recognition Protein PGLYRP2 in the Innate Immune Response to Salmonella enterica Serovar Typhimurium Infection
In Vivo
Authors: Lee Jooeun , Geddes Kaoru , Streutker Catherine , Philpott Dana J. , Girardin Stephen E.
Published: May 2012

Peptidoglycan recognition proteins (PGRPs) are a family of innate pattern recognition molecules that bind bacterial peptidoglycan. While the role of PGRPs in
Drosophila
innate immunity has been extensively studied, how the four mammalian PGRP proteins (PGLYRP1 to PGLYRP4) contribute to host defense against bacterial pathogens
in vivo
remains poorly understood. PGLYRP1, PGLYRP3, and PGLYRP4 are directly bactericidal
in vitro
, whereas PGLYRP2 is an
N
-acetylmuramyl-
l
-alanine amidase that cleaves peptidoglycan between the sugar backbone and the peptide stem. Because PGLYRP2 cleaves muramyl peptides detected by host peptidoglycan sensors Nod1 and Nod2, we speculated that PGLYRP2 may act as a modifier of Nod1/Nod2-dependent innate immune responses. We investigated the role of PGLYRP2 in
Salmonella enterica
serovar Typhimurium-induced colitis, which is regulated by Nod1/Nod2 through the induction of an early Th17 response. PGLYRP2 did not contribute to expression of Th17-associated cytokines, interleukin-22 (IL-22)-dependent antimicrobial proteins, or inflammatory cytokines. However, we found that
Pglyrp2
-deficient mice displayed significantly enhanced inflammation in the cecum at 72 h postinfection, reflected by increased polymorphonuclear leukocyte (PMN) infiltration and goblet cell depletion.
Pglyrp2
expression was also induced in the cecum of
Salmonella
-infected mice, and expression of green fluorescent protein under control of the
Pglyrp2
promoter was increased in discrete populations of intraepithelial lymphocytes. Lastly,
Nod2
−/−
Pglyrp2
−/−
mice displayed increased susceptibility to infection at 24 h postinfection compared to
Pglyrp2
−/−
mice, which correlated with increased PMN infiltration and submucosal edema. Thus, PGLYRP2 plays a protective role
in vivo
in the control of
S
. Typhimurium infection through a Nod1/Nod2-independent mechanism.
Intestinal Epithelial Cells Modulate Antigen-Presenting Cell Responses to Bacterial DNA
Authors: Campeau J. L. , Salim S. Y. , Albert E. J. , Hotte N. , Madsen K. L.
Published: May 2012

Intestinal epithelial cells and antigen-presenting cells orchestrate mucosal innate immunity. This study investigated the role of bacterial DNA in modulating epithelial and bone marrow-derived antigen-presenting cells (BM-APCs) and subsequent T-lymphocyte responses. Murine MODE-K epithelial cells and BM-APCs were treated with DNA from eitherBifidobacterium breveorSalmonella entericaserovar Dublin directly and under coculture conditions with CD4+T cells. Apical stimulation of MODE-K cells withS. Dublin DNA enhanced secretion of cytokines from underlying BM-APCs and induced interleukin-17 (IL-17) and gamma interferon (IFN-γ) secretion from CD4+T cells. Bacterial DNA isolated from either strain induced maturation and increased cytokine secretion from BM-APCs. Conditioned medium fromS. Dublin-treated MODE-K cells elicited an increase in cytokine secretion similar to that seen forS. Dublin DNA. Treatment of conditioned medium from MODE-K cells with RNase and protease prevented theS. Dublin-induced increased cytokine secretion. Oral feeding of mice withB. breveDNA resulted in enhanced levels of colonic IL-10 and transforming growth factor β (TGFβ) compared with what was seen for mice treated withS. Dublin DNA. In contrast, feeding mice withS. Dublin DNA increased levels of colonic IL-17 and IL-12p70. T cells fromS. Dublin DNA-treated mice secreted high levels of IL-12 and IFN-γ compared to controls andB. breveDNA-treated mice. These results demonstrate that intestinal epithelial cells are able to modulate subsequent antigen-presenting and T-cell responses to bacterial DNA with pathogenic but not commensal bacterial DNA inducing effector CD4+T lymphocytes.
Genome Sequences of Pseudomonas fragi Strains A22 and B25
Authors: Mei Yanzhen , Sun Yu , He Jiarong , Wang Qin , Sun Yijing , Shao Weilan
Published: May 2012

Pseudomonas fragi
A22 is a novel isolate that produces bead-like particles (A22B) in its cell wall. To explore the genetic basis for the formation of A22B,
P. fragi
A22 and the type strain of the species,
P. fragi
B25, were subjected to genome sequence analysis. Here, we report the draft genome sequences and automatic annotation of both strains. These data offer a solid base for related studies of
P. fragi
, including comparative genomics, proteomics, and gene mining.
The Genome of Plant Growth-Promoting Bacillus amyloliquefaciens subsp. plantarum Strain YAU B9601-Y2 Contains a Gene Cluster for Mersacidin Synthesis
Authors: Hao Kun , He Pengfei , Blom Jochen , Rueckert Christian , Mao Zichao , Wu Yixin , He Yueqiu , Borriss Rainer
Published: May 2012

The genome of rhizobacterium
Bacillus amyloliquefaciens
subsp.
plantarum
YAU B9601-Y2 was 4.24 Mb in size and harbored 3,991 coding sequences (CDS). Giant gene clusters were dedicated to nonribosomal synthesis of antimicrobial lipopeptides and polyketides. Remarkably, CAU B946 possessed a gene cluster involved in synthesis of mersacidin.
Mindfulness online: a preliminary evaluation of the feasibility of a web-based mindfulness course and the impact on stress
Authors: Krusche Adele , Cyhlarova Eva , King Scott , Williams J Mark G
Published: May 2012

Objectives

Stress has been shown to have a number of negative effects on health over time. Mindfulness interventions have been shown to decrease perceived stress but access to interventions is limited. Therefore, the effectiveness of an online mindfulness course for perceived stress was investigated.

Design

A preliminary evaluation of an online mindfulness course.

Participants

This sample consisted of 100 self-referrals to the online course. The average age of participants was 48 years and 74% were women.

Interventions

The online programme consisted of modules taken from Mindfulness Based Stress Reduction and Mindfulness Based Cognitive Therapy and lasted for approximately 6 weeks.

Primary and secondary outcome measures

Participants completed the Perceived Stress Scale (PSS) before the course, after the course and at 1-month follow-up. Completion of formal (eg, body scan, mindful movement) and informal (eg, mindful meal, noticing) mindfulness activities was self-reported each week.

Results

Participation in the online mindfulness course significantly reduced perceived stress upon completion and remained stable at follow-up. The pre-post effect size was equivalent to levels found in other class-based mindfulness programmes. Furthermore, people who had higher PSS scores before the course reported engaging in significantly more mindfulness practice, which was in turn associated with greater decreases in PSS.

Conclusions

Because perceived stress significantly decreased with such limited exposure to mindfulness, there are implications for the accessibility of mindfulness therapies online. Future research needs to evaluate other health outcomes for which face-to-face mindfulness therapies have been shown to help, such as anxiety and depressive symptoms.
Inter-rater reliability of self-reported response on foreskin status in questionnaire among Japanese adult men
Authors: Yamagishi Takuya , Imai Hirohisa , Nakao Hiroyuki , Yahata Yuichiro , Iizuka Norio , Onoye Yasuhiko , Koichi Udagawa , Misaki Hiroshi , Takaaki Ohyama
Published: May 2012

Objectives

To determine whether foreskin status is a measurable marker for evaluating the effect of the foreskin on sexually transmitted infections.

Methods

Inter-rater comparison of the responses on foreskin status and circumcision in a self-report questionnaire with the findings of a physical examination by an experienced well-trained urologist was performed for patients who visited a healthcare facility in Kanagawa, Japan. Foreskin status was defined using a five-point graphical scale based on the degree to which the foreskin covers the foreskin and the glans penis in a non-erectile condition: type 1, a fully exposed glans penis; types 2–4, the glans penis partly covered by the foreskin and type 5, phimosis. Linear weighted κ and per cent agreement were used to evaluate the reliability of responses.

Results

Among 188 participants who were evaluated about their foreskin status, linear weighted κ and per cent agreement were 0.74% and 68.4%, respectively. Linear weighted κ improved from 0.74 to 0.80 when the number of categories was changed to three. All the self-reported responses on circumcision were in agreement with the findings of the physical examination. Seventeen participants (9.0%) had been circumcised, and among them, three (17.6%) had approximately one-half of their glans penis covered by the foreskin. In 90 among the 171 uncircumcised participants (52.6%), the foreskin did not cover the glans penis.

Conclusions

The self-reported response on foreskin status in this questionnaire has sufficient reliability to replace physical examination, and this questionnaire can facilitate further studies about the effect of foreskin on sexually transmitted infections.
Intermediate vaginal flora is associated with HIV prevalence as strongly as bacterial vaginosis in a cross-sectional study of participants screened for a randomised controlled trial
Authors: Guédou Fernand Aimé , Van Damme Lut , Mirembe Florence , Solomon Suniti , Becker Marissa , Deese Jennifer , Crucitti Tania , Alary Michel
Published: May 2012

Objective

The authors analysed data from female sex workers screened prior to participation in a microbicide trial to examine the association between prevalent vaginal flora abnormalities and HIV infection, with special emphasis on the role of the intermediate vaginal flora (IVF) in this association.

Methods

Data from the Kampala, Cotonou, Chennai and Mudhol/Jamkhandi sites were analysed. Participants were interviewed and provided blood for HIV and syphilis antibody testing, genital samples for the diagnosis of vaginal flora abnormalities (using Nugent score) and other reproductive tract infections. Log-binomial regression was used to estimate the HIV prevalence ratio (PR) in relation to IVF and bacterial vaginosis (BV).

Results

Among 1367 women, BV, IVF and HIV prevalences were 47.6% (95% CI=45.0% to 50.3%), 19.2% (95% CI=17.1% to 21.2%) and 27.0% (95% CI=24.6% to 29.3%), respectively. In multivariate analysis, adjusting for study site, age, years of education, occupation, female sterilisation, oral sex, past history of sexually transmitted infection, gonorrhoea and candidiasis, IVF was significantly associated with HIV infection with a PR similar to that of BV (adjusted PR=1.56 (95% CI=1.22 to 1.98) and 1.48 (95% CI=1.20 to 1.84), respectively).

Conclusions

Though the cross-sectional design of the study precludes directional interpretation of the findings, the data do suggest that IVF may be as important as BV in HIV acquisition. The authors recommend prospective research to better understand the association between IVF and HIV acquisition.
WRINKLING ATOP SHAPE MEMORY MATERIALS
Authors: SUN L. , ZHAO Y. , HUANG W. M. , PURNAWALI H. , FU Y. Q.
Published: May 2012

Many surface related properties, such as surface roughness, surface tension and reflection etc are heavily dependent on the surface morphology of materials. Patterned surfaces may have significant effects on these properties. In this paper, we compare wrinkles produced atop three different types of shape memory materials, namely, shape memory alloy, shape memory polymer and shape memory hybrid. We show the advantages and disadvantages of them in terms of the processing techniques and the resultant wrinkle patterns.
EFFECT OF SUBSTRATE TEMPERATURE ON THE GROWTH AND PROPERTIES OF ZnO:Al THIN FILMS
Authors: LEI JINSONG , ZOU YINSHENG
Published: May 2012

ZnO:Al (AZO) transparent conductive films used for solar cells were prepared by DC magnetron sputtering technology. The influence of substrate temperature on the electrical and optical properties of the films was studied. Further, the AZO films prepared were etched in diluted hydrochloric acid. The film surface morphology after etching for different time was researched.
STOCHASTIC VOLTERRA EQUATIONS DRIVEN BY FRACTIONAL BROWNIAN MOTION WITH HURST PARAMETER H > 1/2
Authors: BESALÚ MIREIA , ROVIRA CARLES
Published: May 2012

In this note we prove an existence and uniqueness result of solution for stochastic Volterra integral equations driven by a fractional Brownian motion with Hurst parameter H > 1/2, showing also that the solution has finite moments. The stochastic integral with respect to the fractional Brownian motion is a pathwise Riemann–Stieltjes integral.
APPLICATION OF TECHNETIUM AND RHENIUM IN NUCLEAR MEDICINE
Authors: ALBERTO ROGER
Published: May 2012

Technetium and Rhenium are the two lower elements in the manganese triad. Whereas rhenium is known as an important part of high resistance alloys, technetium is mostly known as a cumbersome product of nuclear fission. It is less known that its metastable isotope 99mTc is of utmost importance in nuclear medicine diagnosis. The technical application of elemental rhenium is currently complemented by investigations of its isotope 188Re , which could play a central role in the future for internal, targeted radiotherapy. This article will briefly describe the basic principles behind diagnostic methods with radionuclides for molecular imaging, review the 99mTc -based radiopharmaceuticals currently in clinical routine and focus on the chemical challenges and current developments towards improved, radiolabeled compounds for diagnosis and therapy in nuclear medicine.
Spontaneous Polygonization of Multiwalled Carbon Nanotubes: Perturbation Analysis
Authors: Mu Weihua , Zhang Gang , Ou-Yang Zhongcan
Published: May 2012

Spontaneous polygonization for a multiwalled carbon nanotubes (MWCNTs) without external pressure is understood by the competition between cohesion energy (with lattice mismatching and defect's effect) and curvature elastic energy of tubes inside the MWCNTs. Based on a continuum elastic model and perturbation analysis, the crucial conditions for spontaneous polygonization of MWCNT is expressed by fundamental parameters of MWCNTs, which are in reasonable agreement with all relevant experiments and computer simulations reported in literatures. Present approach can be used in further studies of crossectional geometry-dependent electronic properties of MWCNTs and other inorgnic nanotubes.
Adipogenesis: From Stem Cell to Adipocyte
Authors: Tang Qi Qun , Lane M. Daniel
Published: May 2012

Excessive caloric intake without a rise in energy expenditure promotes adipocyte hyperplasia and adiposity. The rise in adipocyte number is triggered by signaling factors that induce conversion of mesenchymal stem cells (MSCs) to preadipocytes that differentiate into adipocytes. MSCs, which are recruited from the vascular stroma of adipose tissue, provide an unlimited supply of adipocyte precursors. Members of the BMP and Wnt families are key mediators of stem cell commitment to produce preadipocytes. Following commitment, exposure of growth-arrested preadipocytes to differentiation inducers [insulin-like growth factor 1 (IGF1), glucocorticoid, and cyclic AMP (cAMP)] triggers DNA replication and reentry into the cell cycle (mitotic clonal expansion). Mitotic clonal expansion involves a transcription factor cascade, followed by the expression of adipocyte genes. Critical to these events are phosphorylations of the transcription factor CCATT enhancer-binding protein β (C/EBPβ) by MAP kinase and GSK3β to produce a conformational change that gives rise to DNA-binding activity. “Activated” C/EBPβ then triggers transcription of peroxisome proliferator–activated receptor-γ (PPARγ) and C/EBPα, which in turn coordinately activate genes whose expression produces the adipocyte phenotype.
Ubiquitin and Proteasomes in Transcription
Authors: Geng Fuqiang , Wenzel Sabine , Tansey William P.
Published: May 2012

Regulation of gene transcription is vitally important for the maintenance of normal cellular homeostasis. Failure to correctly regulate gene expression, or to deal with problems that arise during the transcription process, can lead to cellular catastrophe and disease. One of the ways cells cope with the challenges of transcription is by making extensive use of the proteolytic and nonproteolytic activities of the ubiquitin-proteasome system (UPS). Here, we review recent evidence showing deep mechanistic connections between the transcription and ubiquitin-proteasome systems. Our goal is to leave the reader with a sense that just about every step in transcription—from transcription initiation through to export of mRNA from the nucleus—is influenced by the UPS and that all major arms of the system—from the first step in ubiquitin (Ub) conjugation through to the proteasome—are recruited into transcriptional processes to provide regulation, directionality, and deconstructive power.