bluuebunny/crossref_metadata_2025 huggingface dataset:
Prevalence and Utility of Positive Pneumococcal Urinary Antigen Tests in Australian Patients with Community-Acquired Pneumonia
Authors: Troy Lauren K. , Wong Keith K. H. , Barnes David J.
Published: September 2012

Background and Objectives. The pneumococcal urinary antigen test (UAT) has superior sensitivity to other investigations in determining the aetiology of community-acquired pneumonia (CAP), but data specific to Australian populations is limited. This study aimed to establish the prevalence and clinical utility of positive UAT in patients admitted to hospital with CAP, as well as associations with positive testing. Methods. A prospective, cross-sectional, single-centre study was performed. Urine antigen tests were performed on all adult patients admitted to hospital with the diagnosis of CAP. Sputum and blood culture results, CURB-65 score of severity, current and prior antibiotics, comorbidities, mortality, and length of hospital stay were recorded. Results. There was a positive test prevalence of 13/170 [7.6% (95% confidence intervals 4.3–13%)]. The overall prevalence of pneumococcal pneumonia was 19/170 (11%), including 8 patients confirmed on positive UAT alone. Patients with a positive UAT result had a higher mean CURB-65 score compared with those with a negative result (P=0.01), and a greater likelihood of requiring intensive care support (P=0.006). Conclusions. The prevalence of positive UAT was low. Positive results were more often recorded in those with greater severity pneumonia. The clinical utility of the test in this cohort of patients was low.
CVD and PVD coating process modelling by using artificial neural networks
Authors: Khorasani Amir Mahyar , Solymany yazdi Mohammad Reza , Faraji Mehdi , Kootsookos Alex
Published: September 2012

Thin-film coating plays a prominent role on the manufacture of many industrial devices. Coating can increase material performance due to the deposition process. Having adequate and precise model that can predict the hardness of PVD and CVD processes is so helpful for manufacturers and engineers to choose suitable parameters in order to obtain the best hardness and decreasing cost and time of industrial productions. This paper proposes the estimation of hardness of titanium thin-film layers as protective industrial tools by using multi-layer perceptron (MLP) neural network. Based on the experimental data that was obtained during the process of chemical vapor deposition (CVD) and physical vapor deposition (PVD), the modeling of the coating variables for predicting hardness of titanium thin-film layers, is performed. Then, the obtained results are experimentally verified and very accurate outcomes had been attained.
Hyperspectral image classification incorporating bacterial foraging-optimized spectral weighting
Authors: Chakrabarty Ankush , Choudhury Olivia , Sarkar Pallab , Paul Avishek , Sarkar Debarghya
Published: September 2012

The present paper describes the development of a hyperspectral image classification scheme using support vector machines (SVM) with spectrally weighted kernels. The kernels are designed during the training phase of the SVM using optimal spectral weights estimated using the Bacterial Foraging Optimization (BFO) algorithm, a popular modern stochastic optimization algorithm. The optimized kernel functions are then in the SVM paradigm for bi-classification of pixels in hyperspectral images. The effectiveness of the proposed approach is demonstrated by implementing it on three widely used benchmark hyperspectral data sets, two of which were taken over agricultural sites at Indian Pines, Indiana, and Salinas Valley, California, by the Airborne Visible Infra-Red Imaging Spectrometer (AVIRIS) at NASA’s Jet Propulsion Laboratory. The third dataset was acquired using the Reflective Optical System Imaging Spectrometer (ROSIS) over an urban scene at Pavia University, Italy to demonstrate the efficacy of the proposed approach in an urban scenario as well as with agricultural data. Classification errors for One-Against-One (OAO) and classification accuracies for One-Against-All (OAA) schemes were computed and compared to other methods developed in recent times. Finally, the use of the BFO-based technique is recommended owing to its superior performance, in comparison to other contemporary stochastic bio-inspired algorithms.
Parallel hybrid enhanced inherited GA based scuc in a distributed cluster
Authors: C Christopher Columbus , Simon Sishaj P.
Published: September 2012

In the deregulated electricity market, secure operation is an enduring concern of the independent system operator (ISO). For a secure and economical hourly generation schedule of the day ahead market, ISO executes the security constrained unit commitment (SCUC) problem. In this paper, a new formulation of SCUC problem, considering more practical constraints are presented. The proposed SCUC formulation includes constraints, such as hourly power demand, system reserves, ramp up/down limits, minimum ON/OFF duration limits. Unlike the traditional SCUC techniques the proposed method solves the Security Constrained Economic Dispatch (SCED) from the UC. To solve such SCUC model, a hybrid solution method consists of an enhanced inherited genetic algorithm (EIGA) is used for unit commitment master problem and Lambda relaxation method is used for the economic dispatch sub-problem. The message passing interface (MPI) based technique is used to implement the hybrid EIGA in distributed memory model. The time complexity and the solution quality with respect to the number of processors in a cluster are thoroughly analyzed. The effectiveness of the proposed method to solve the SCUC problem is shown on different test systems.
Health policies in transition economics
Authors: Rudraswamy Sushma , Doggalli Nagabhushana
Published: September 2012

Historical evidence indicates that economic transformation, even with access and growth, can translate into social insecurities and health problems. The issue here is not whether transition economics should continue their reform process or not, since this has been historically proven necessary for the development of a country. Rather, it is about what the government can do to alleviate health problems through the adoption and implementation of sound policies. Since the health of a nation is strongly dependent on social, economic, and political stability sound health policies have to go hand in hand with adequate economic policies and a set of measures to ensure a social safety net to protect the relatively deprived. Better health for the population should be the ultimate goal of health policies. Reforming health services and finance is just a means towards that end.
Concise Review: Therapeutic Potential of Adipose Tissue-Derived Angiogenic Cells
Authors: Szöke Krisztina , Brinchmann Jan E.
Published: September 2012

Inadequate blood supply to tissues is a leading cause of morbidity and mortality today. Ischemic symptoms caused by obstruction of arterioles and capillaries are currently not treatable by vessel replacement or dilatation procedures. Therapeutic angiogenesis, the treatment of tissue ischemia by promoting the proliferation of new blood vessels, has recently emerged as one of the most promising therapies. Neovascularization is most often attempted by introduction of angiogenic cells from different sources. Emerging evidence suggests that adipose tissue (AT) is an excellent reservoir of autologous cells with angiogenic potential. AT yields two cell populations of importance for neovascularization: AT-derived mesenchymal stromal cells, which likely act predominantly as pericytes, and AT-derived endothelial cells (ECs). In this concise review we discuss different physiological aspects of neovascularization, briefly present cells isolated from the blood and bone marrow with EC properties, and then discuss isolation and cell culture strategies, phenotype, functional capabilities, and possible therapeutic applications of angiogenic cells obtained from AT.
Homeostatic Imbalance in Epithelial Ducts and Its Role in Carcinogenesis
Authors: Rejniak Katarzyna A.
Published: September 2012

An epithelial duct is a well-defined multicellular structure composed of tightly packed cells separating and protecting body compartments that are used for enzyme secretion and its transport across the internal. The structural and functional integrity (homeostasis) of such ducts is vital in carrying many life functions (breathing, lactation, production of hormones). However, the processes involved in maintaining the homeostatic balance are not yet fully understood. On the other hand, the loss of epithelial tissue architecture, such as filled lumens or ductal disorganization, are among the first symptoms of the emerging epithelial tumors (carcinomas). Using the previously developed biomechanical model of epithelial ducts:IBCell, we investigated how different signals and mechanical stimuli imposed on individual epithelial cells can impact the homeostatic (im)balance and integrity of the whole epithelial tissue. We provide a link between erroneous responses of individual epithelial cells to specific signals and the emerging ductal morphologies characteristic for preinvasive cancers observed in pathology specimens, or characteristic for multicellular structures arising from mutated cells culturedin vitro. We summarize our finding in terms of altered properties of epithelial cell polarization, and discuss the relative importance of various polarization signals on the formation of tumor-like multicellular structures.
Within-Niche Constant Selection ofDrosophilaInversions?
Authors: Álvarez-Castro José M. , Alvarez Gonzalo
Published: September 2012

Extensive and fruitful work is being devoted for more than 70 years to elucidate the fine points of the maintenance of inversion polymorphisms of the genusDrosophila. Recent studies have resumed selection in heterogeneous environments (or niches) as a major underlying mechanism for these balanced polymorphisms. In those studies, constant selection within niches is assumed throughout although this assumption is since long known not to hold. In the present communication it is sustained that the results in those studies are robust in the face of this fact. To that end, this communication deals with a particular long-lasting question within this topic—whether the minimal model of constant viability selection (MCV, assuming frequency-, sex-, and stage-independent adaptive values) suffices to reproduce the trajectories of frequencies of Drosophila chromosomal arrangements observed in experimental populations along generations under homogeneous environments. Fitness estimates are here obtained from published trajectories of frequencies using a maximum likelihood approach, and relevant literature is revised in the light of these new analyses, pointing to an affirmative answer to that question.
Smaller Fleas: Viruses of Microorganisms
Authors: Hyman Paul , Abedon Stephen T.
Published: September 2012

Life forms can be roughly differentiated into those that are microscopic versus those that are not as well as those that are multicellular and those that, instead, are unicellular. Cellular organisms seem generally able to host viruses, and this propensity carries over to those that are both microscopic and less than truly multicellular. These viruses of microorganisms, or VoMs, in fact exist as the world’s most abundant somewhat autonomous genetic entities and include the viruses of domain Bacteria (bacteriophages), the viruses of domain Archaea (archaeal viruses), the viruses of protists, the viruses of microscopic fungi such as yeasts (mycoviruses), and even the viruses of other viruses (satellite viruses). In this paper we provide an introduction to the concept of viruses of microorganisms, a.k.a., viruses of microbes. We provide broad discussion particularly of VoM diversity. VoM diversity currently spans, in total, at least three-dozen virus families. This is roughly ten families per category—bacterial, archaeal, fungal, and protist—with some virus families infecting more than one of these microorganism major taxa. Such estimations, however, will vary with further discovery and taxon assignment and also are dependent upon what forms of life one includes among microorganisms.
Temporal changes in cardiorespiratory fitness and the incidence of hypertension in initially normotensive subjects
Authors: Jae Sae Young , Heffernan Kevin S. , Yoon Eun Sun , Park Soo Hyun , Carnethon Mercedes R. , Fernhall Bo , Choi Yoon‐Ho , Park Won Hah
Published: September 2012

Objectives:

Low‐cardiorespiratory fitness (CRF) has been associated with incident hypertension, but whether temporal changes in CRF are associated with incident hypertension in initially normotensive subjects are not known. We investigated the relationship of baseline CRF and longitudinal changes in CRF with incident hypertension in initially normotensive subjects.

Methods:

Subjects were 3,831 men who participated in two health examinations during 1998–2009. All subjects were free of cardiovascular diseases and hypertension at baseline. CRF was directly measured by peak oxygen uptake using expired gas analysis during a standard treadmill test.

Results:

During an average of 5 years of follow‐up, 373 (9.7%) subjects developed hypertension. The incidence of hypertension was inversely associated with baseline CRF quartiles [Q1 (lowest) 11.8%, Q2 10.4%, Q3 9.1%, and Q4 (highest) 7.5%; P < 0.05 for trend]. The relative risk (RR) of incident hypertension in the lowest CRF quartile versus the highest CRF quartile was 1.69 (95% CI: 1.22–2.34) after adjustment for risk factors. Each metabolic equivalent increment higher peak oxygen uptake at baseline examination was associated with 10% (RR 0.90, 95% CI: 0.83–0.98) lower incidence of hypertension in multivariate adjusted model. Subjects whose CRF decreased (<−1.18 ml/kg/min per year) over time had a 72% increased risk in developing hypertension (RR 1.72, 95% CI: 1.20–2.49) compared to subjects with increased CRF (>0.13 ml/kg/min per year) after adjustment for risk factors.

Conclusion:

These results demonstrate that both baseline CRF levels and changes in CRF over time were associated with the incidence of hypertension independent of risk factors. Am. J. Hum. Biol. 2012. © 2012 Wiley Periodicals, Inc.
The earliest evidence of millet as a staple crop: New light on neolithic foodways in North China
Authors: Liu Xinyi , Jones Martin K. , Zhao Zhijun , Liu Guoxiang , O'Connell Tamsin C.
Published: September 2012

There is a growing body of archaeobotanical evidence for the harvesting of millet in Eurasia prior to 5,000 cal. BC. Yet direct evidence for the extent of millet consumption in this time period is rare. This contradiction may be due to millet crops making only a minor contribution to the diet before 5,000 BC. In this article, drawing from recent excavations in North China, we present evidence for millet crops making a substantial contribution to human and animal diets in periods, which correspond chronologically with the time depth of the archaeobotanical record. We infer that in eastern Inner Mongolia, human adoption of millets, which may or may be not related to substantial agriculture, happened at the Early Neolithic, with direct dates between 5,800 and 5,300 cal. BC. Am J Phys Anthropol 149:283–290, 2012. © 2012 Wiley Periodicals, Inc.
Genetic variants in the immunoglobulin heavy chain locus are associated with the IgG index in multiple sclerosis
Authors: Buck Dorothea , Albrecht Eva , Aslam Muhammad , Goris An , Hauenstein Natalie , Jochim Angela ,   International Multiple Sclerosis Genetics Consortium, Wellcome Trust Case Control Consortium, Cepok Sabine , Grummel Verena , Dubois Bénédicte , Berthele Achim , Lichtner Peter , Gieger Christian , Winkelmann Juliane , Hemmer Bernhard
Published: September 2012

Objective:

Intrathecal synthesis of immunoglobulin gamma (IgG) synthesis is frequently observed in patients with multiple sclerosis (MS). Whereas the extent of intrathecal IgG synthesis varies largely between patients, it remains rather constant in the individual patient over time. The aim of this study was to identify common genetic variants associated with the IgG index as a marker of intrathecal IgG synthesis in MS.

Methods:

We performed a genome‐wide association study of the IgG index in a discovery series of 229 patients. For confirmation we performed a replication in 2 independent series comprising 256 and 153 patients, respectively. The impact of associated single nucleotide polymorphisms (SNPs) on MS susceptibility was analyzed in an additional 1,854 cases and 5,175 controls.

Results:

Significant association between the IgG index and 5 SNPs was detected in the discovery and confirmed in both replication series reaching combined p values of p = 6.5 × 10−11 to p = 7.5 × 10−16. All identified SNPs are clustered around the immunoglobulin heavy chain (IGHC) locus on chromosome 14q32.33 and are in linkage disequilibrium (r2 range, 0.71–0.95). The best associated SNP is located in an intronic region of the immunoglobulin gamma3 heavy chain gene. Additional sequencing identified the GM21* haplotype to be associated with a high IgG index. Further evaluation of the IGHC SNPs revealed no association with susceptibility to MS in our data set.

Interpretation:

The extent of intrathecal IgG in MS is influenced by the IGHC locus. No association with susceptibility to MS was found. Therefore GM haplotypes might affect intrathecal IgG synthesis independently of the underlying disease. ANN NEUROL 2013
Electron transfer dynamics of peptide‐derivatized RuII‐polypyridyl complexes on nanocrystalline metal oxide films
Authors: Hanson Kenneth , Wilger Dale J. , Jones Sean T. , Harrison Daniel P. , Bettis Stephanie E. , Luo Hanlin , Papanikolas John M. , Waters Marcey L. , Meyer Thomas J.
Published: September 2012

The performance of dye‐sensitized solar and photoelectrochemical cells is strongly dependent on the electron transfer events at the electrode‐sensitizer interface. Surface‐bound peptides derivatized with chromophores have not been used in dye‐sensitized solar and photoelectrochemical cells, but they have properties for these applications that could be advantageous by exploiting secondary structure and the attachment of multiple chromophores. In this manuscript, we have investigated structure–property relationships for three metallopeptide‐based assemblies to solution and chemically bound to nanocrystalline MO2 (M = Ti, Zr) films. A particular interest was exploring the influence of increasing separation distance between a common chromophore, [Ru(bpy)2(4‐Me‐4′‐(NHCO)bpy)]2+, and the underlying oxide substrate on excited and ground state electron transfer. Rates of Ru(II) oxidation to Ru(III) at the interface were measured by cyclic voltammetry on fluorine‐doped tin oxide and cross‐surface electron transfer on TiO2. Excited state injection by [RuIII(bpy)2(bpy−)]2+ was monitored by transient absorption and time‐resolved emission. There are discernible trends in the electron transfer rate data with approximated, fully extended distances between the [Ru(bpy)2(4‐Me‐4′‐(NHCO)bpy)]2+ sites and the interface. However, the distance dependences that are observed are smaller than anticipated, a result consistent with a lack of ordered secondary structure in the surface‐bound peptide chains and a distribution of local orientations. For the surface‐bound excited states, only a small fraction undergo quenching by electron transfer to TiO2, presumably from those oriented near the surface. © 2012 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 100: 25–37, 2013.
β2 and γ3 laminins are critical cortical basement membrane components: Ablation of Lamb2 and Lamc3 genes disrupts cortical lamination and produces dysplasia
Authors: Radner Stephanie , Banos Charles , Bachay Galina , Li Yong N. , Hunter Dale D. , Brunken William J. , Yee Kathleen T.
Published: September 2012

Cortical development is dependent on the timely production and migration of neurons from neurogenic sites to their mature positions. Mutations in several receptors for extracellular matrix (ECM) molecules and their downstream signaling cascades produce dysplasia in brain. Although mutation of a critical binding site in the gene that encodes the ECM molecule laminin γ1 (Lamc1) disrupts cortical lamination, the ECM ligand(s) for many ECM receptors have not been demonstrated directly in the cortex. Several isoforms of the heterotrimeric laminins, all containing the β2 and γ3 chain, have been isolated from the brain, suggesting they are important for CNS function. Here, we report that mice homozygous null for the laminin β2 and γ3 chains exhibit cortical laminar disorganization. Mice lacking both of these laminin chains exhibit hallmarks of human cobblestone lissencephaly (type II, nonclassical): they demonstrate severe laminar disruption; midline fusion; perturbation of Cajal‐Retzius cell distribution; altered radial glial cell morphology; and ectopic germinal zones. Surprisingly, heterozygous mice also exhibit laminar disruption of cortical neurons, albeit with lesser severity. In compound null mice, the pial basement membrane is fractured, and the distribution of a key laminin receptor, dystroglycan, is altered. These data suggest that β2 and γ3‐containing laminins play an important dose‐dependent role in development of the cortical pial basement membrane, which serves as an attachment site for Cajal‐Retzius and radial glial cells, thereby guiding neural development. © 2012 Wiley Periodicals, Inc. Develop Neurobiol, 2013
The osteogenic differentiation improvement of human mesenchymal stem cells on titanium grafted with polyNaSS bioactive polymer
Authors: Oughlis S. , Lessim S. , Changotade S. , Poirier F. , Bollotte F. , Peltzer J. , Felgueiras H. , Migonney V. , Lataillade J. J. , Lutomski D.
Published: September 2012

Osseointegration of metallic implants used in orthopedic surgery requires that osteoprogenitor cells attach and adhere to the surface, then proliferate, differentiate into osteoblasts, and finally produce mineralized matrix. Because the ability of progenitor cells to attach to a scaffold surface during early stages is important in the development of new tissue structures, we developed in our laboratory, a strategy involving grafting of implants with a polymer of sodium styrene sulfonate (polyNaSS) used as a scaffold which enables human mesenchymal stem cells (hMSCs) interactions. In the present study, we investigated the cellular response of hMSCs to polyNaSS surfaces of titanium (Ti). In particular, cell proliferation, cell viability, cell differentiation, and cell spreading were evaluated. Results showed that cell proliferation and cell viability did not differ with any statistical significance between modified and unmodified Ti surfaces. Interestingly, culture of MSCs on polyNaSS surfaces resulted in a significant increase of cell spreading and cell differentiation compared with the other tested surfaces. These results suggest that titanium surface grafted with polyNaSS is a suitable scaffold for bone tissue engineering. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
The mineralization inducing peptide derived from dentin sialophosphoprotein for bone regeneration
Authors: Choi Young Suk , Lee Jue Yeon , Suh Jin Sook , Lee Gene , Chung Chong Pyoung , Park Yoon Jeong
Published: September 2012

Dentin sialophosphoprotein (DSPP) has been shown to play a primary role in the formation and growth of hydroxyapatite crystals in an extracellular matrix of hard tissue such as bone and teeth. We hypothesized that the mineralization ability of DSPP might depend on a specific domain within it. Three peptides, which have hydroxyapatite (HA) binding affinity, denoted as mineralization inducing peptide (MIP1, MIP2, and MIP3) were identified from DSPP. The both of MIP2 and MIP3 had HA nucleation activity demonstrated by XRD. Among three MIPs, MIP3 significantly supported the human bone marrow stromal cell differentiation into osteoblastic cells. An immunoblot with antibodies specific for the phosphorylated forms of ERK was conducted with cells treated by MIP3. MIP3 transduced intracellular signals via the ERK pathways and was able to induce osteoblastic differentiation, as seen by high expression of ALP, type 1 collagen, OC, OPN, and Runx2 in accordance with applied MIP3 concentration. The Asp, Glu, and Ser residues in MIP3 play important roles for the affinity of calcium in HA bone mineral. Further animal experiment with MIP3 in combination with hydroxyapatite mineral induced marked new bone formation for 4 weeks at rabbit calvarial defect model. The new bone area was much higher in test group, implying that the peptide modified group had excellent biocompatibility when compared with the unmodified group. Taken together, the MIP from DSPP has potential to enhance mineralization followed by to enhance osteoblastic differentiation and bone regeneration. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Synthesis and fabrication of a degradable poly(N‐isopropyl acrylamide) scaffold for tissue engineering applications
Authors: Galperin Anna , Long Thomas J. , Garty Shai , Ratner Buddy D.
Published: September 2012

Biodegradable poly(N‐isopropyl acrylamide) (polyNIPAM) hydrogels with controlled molecular weight of the parent polymer and its degradation products were synthesized by atom transfer radical polymerization in the presence of a polycaprolactone‐based di‐chlorinated macroinitiator and polycaprolactone dimethacrylate. The phase transition temperature, swelling, hydrolytic degradability, and mechanical properties at 25 and 37°C were explored. A cytocompatibility study showed good NIH3T3 cell response over 5 days culture on the surface of the hydrogels, demonstrated by a consistent increase in cell proliferation detected by an Alamar Blue assay. MTT [3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyltetrazolium bromide] results suggested that the hydrogels and their degradation products in the concentration range of 1–25 mg/mL were not cytotoxic to NIH3T3 cells. A sphere‐templating technique was utilized to fabricate biodegradable polyNIPAM scaffolds with monodisperse, pore size. Scaffolds with pore diameter of 48 ± 6 μm were loaded with A‐10 smooth muscle cells and then warmed to 37°C entrapping cells in pores approximately 40 μm in diameter, a size we have found to be optimal for angiogenesis and biointegration. Due to their degradable nature, tunable molecular weight, highly interconnected morphology, thermally controlled monodisperse pore size, and temperature‐induced volume expansion–contraction, the polyNIPAM‐based scaffolds developed in this work will be valuable in tissue engineering. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 101A: 775–786, 2013.
Comparative analysis of photocaged RGDS peptides for cell patterning
Authors: Goubko Catherine A. , Basak Ajoy , Majumdar Swapan , Jarrell Harold , Huan Khieu Nam , Cao Xudong
Published: September 2012

Photocaged RGDS is a cell nonadhesive tetrapeptide that can be activated with light to become cell‐adhesive. Such molecules can find useful applications in controlling cell adhesion for biological study, drug development, and in forming dynamic, adhesion‐controlled biomaterials. Herein, we prepared RGDS peptide photocaged either on the Arg‐Gly backbone amide nitrogen atom (R[−]GDS) or Asp side chain carboxyl (RG[D]S). A critical comparison of the peptides' chemical and physiological properties relevant for biological applications was carried out. It was observed that RG[D]S was synthesized more readily via automated solid‐phase synthesis, underwent uncaging with a rate constant 3‐fold higher than R[−]GDS, and was more stable in aqueous solution. Automated docking studies were performed to examine the interactions of various caged RGDS peptides with cell surface integrin receptor to identify suitable locations for the photosensitive 2‐nitrobenzyl (NB) group for biological applications. A competitive binding ELISA method compared the ability of various peptides to bind to αVβ3 cell integrin receptors and the data were found to be consistent with the modeling predictions. Finally, the application of our caged RGDS peptides in controlling cell adhesion to form cell patterns on a hydrogel material was presented. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 101A: 787–796, 2013.
In vitro and in vivo studies of rhBMP2‐coated PS/PCL fibrous scaffolds for bone regeneration
Authors: Nguyen Thi‐Hiep , Lee Byong‐Taek
Published: September 2012

The control of porous microstructure and the use of rhBMP2 as surface coating on bone substitutes have been recognized as key factors to accelerate osteoconductivity. In this study, instead of using a meso‐porous fibrous scaffold of poly‐ε‐caprolactone (PCL), a micro‐ and macro‐porous fibrous scaffold, made up of blended polystyrene (PS) and PCL, was created to investigate these key factors. In vitro studies, MTT assay and scanning electron microscope (SEM) morphology confirmed that PS/PCL fibrous membrane has non‐toxicity and shows excellent cells adhesion and proliferation behavior. Significant improvements regarding cell attachment, cell growth, and cell proliferation were observed using recombinant human bone morphogenetic protein‐2 (rhBMP2)‐coated PS/PCL fibrous scaffold confirmed by SEM and confocal observation. Results of micro‐CT scanning and the Hematoxylin & Eosin/Masson's Trichrom staining of tissue sections from the post‐implantation revealed that rhBMP2‐coated PS/PCL fibrous scaffold recovered over 75 vol % of the bone defect after 8 weeks of implantation. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 101A: 797–808, 2013.
A novel suture‐based method for efficient transplantation of stem cells
Authors: Guyette Jacques P. , Fakharzadeh Michael , Burford Evans J. , Tao Ze‐Wei , Pins George D. , Rolle Marsha W. , Gaudette Glenn R.
Published: September 2012

Advances in regenerative medicine have improved the potential of using cellular therapy for treating several diseases. However, the effectiveness of new cellular therapies is largely limited by low cell engraftment and inadequate localization. To improve on these limitations, we developed a novel delivery mechanism using cell‐seeded biological sutures. We demonstrate the ability of cell‐seeded biological sutures to efficiently implant human mesenchymal stem cells (hMSCs) to specific regions within the beating heart; a tissue known to have low cell retention and engraftment shortly after delivery. Cell‐seeded biological sutures were developed by bundling discrete microthreads extruded from extracellular matrix proteins, attaching a surgical needle to the bundle and seeding the bundle with hMSCs. During cell preparation, hMSCs were loaded with quantum dot nanoparticles for cell tracking within the myocardium. Each biological suture contained an average of 5903 ± 1966 hMSCs/cm suture length. Delivery efficiency was evaluated by comparing cell‐seeded biological suture implantation with intramyocardial (IM) cell injections (10,000 hMSCs in 35 μL) into the left ventricle of normal, noninfarcted rat hearts after 1 h. Delivery efficiency of hMSCs by biological sutures (63.6 ± 10.6%) was significantly higher than IM injection (11.8 ± 6.2%; p < 0.05). Cell‐tracking analysis indicated suture‐delivered hMSCs were found throughout the thickness of the ventricular myocardium: along the entire length of the biological suture track, localizing closely with native myocardium. These results suggest cell‐seeded biological sutures can deliver cells to the heart more efficiently than conventional methods, demonstrating an effective delivery method for implanting cells in soft tissue. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 101A: 809–818, 2013.
Characterization of polyurethane scaffold surface functionalization with diamines and heparin
Authors: de Mulder Eric L. W. , Hannink Gerjon , Koens Martin J. W. , Löwik Dennis W. P. M. , Verdonschot Nico , Buma Pieter
Published: September 2012

Polyurethane scaffolds (PUs) have a good biocompatibility but lack cell recognition sites. In this study, we functionalized the surface of a PU, P(D/L)LA and PCL (50:50) containing urethane segments, with heparin. The first step in this functionalization, aminolysis, lead to free amine groups on the surface of the PU. Free amine content was determined to be 6.4 nmol/mL/mg scaffold, a significant increase of 230%. Subsequently, heparin was crosslinked. Immunohistochemistry demonstrated the presence of heparin homogeneous throughout the 3D porous scaffold. Young's modulus decreased significantly till 50% of the native stiffness after aminolysis and did not change after heparin crosslinking. Contact angle on PU films significantly decreased from 82.7° to 64.3° after heparin crosslinking, indicating a more hydrophilic surface. This functionalization beholds great potential for tissue engineering purposes. When used in a load‐bearing environment, caution is necessary due to reduction in mechanical stiffness. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Calcium phosphate glass improves angiogenesis capacity of poly(lactic acid) scaffolds and stimulates differentiation of adipose tissue‐derived mesenchymal stromal cells to the endothelial lineage
Authors: Vila Olaia F. , Bagó Juli R. , Navarro Melba , Alieva Maria , Aguilar Elisabeth , Engel Elisabeth , Planell Josep , Rubio Nuria , Blanco Jerónimo
Published: September 2012

The angiogenic capacity of a new biomaterial composite of poly(lactic acid) and calcium phosphate glass (PLA/CaP) was analyzed by noninvasive bioluminescence imaging (BLI) and histological procedures. Human adipose tissue‐derived mesenchymal stromal cells expressing cytomegalovirus (CMV) promoter regulated Photinus
pyralis luciferase (hAMSC‐PLuc) grew up to 30 times the initial cell load, in vitro, when seeded in PLA/CaP scaffolds, but suffered an initial growth crisis followed by recovery when the scaffolds were subcutaneously implanted in SCID mice. To analyze changes in gene expression, hAMSC‐PLuc cells were double labeled with a CMV promoter regulated Renilla reniformis luciferase and a Photinus
pyralis luciferase reporter regulated by either the PECAM promoter or a hypoxia response element (HRE) artificial promoter and seeded in PLA/CaP and PLA scaffolds implanted in SCID mice. Analysis by BLI showed that hAMSCs in scaffolds were induced to differentiate to the endothelial lineage and did this faster in PLA/CaP than in PLA scaffolds. Endothelial differentiation correlated with a decrease in the activity of HRE regulated luciferase expression, indicative of a reduction of hypoxia. Histological analysis showed that PLA/CaP scaffolds were colonized by a functional host vascular system. Moreover, colonization by isolectin B4 positive host cells was more effective in PLA/CaP than in PLA scaffolds, corroborating BLI results. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Generation of osteogenic construct using periosteal‐derived osteoblasts and polydioxanone/pluronic F127 scaffold with periosteal‐derived CD146 positive endothelial‐like cells
Authors: Lee Jin Ho , Kim Shin‐Won , Kim Uk‐Kyu , Oh Se Heang , June‐Kim Sang , Park Bong‐Wook , Kim Jin‐Hyun , Hah Young‐Sool , Kim Deok Ryong , Rho Gyu‐Jin , Maeng Geun‐Ho , Jeon Ryoung‐Hoon , Lee Hee‐Chun , Kim Jong‐Ryoul , Kim Gyoo‐Cheon , Byun June‐Ho
Published: September 2012

The purpose of this study was to generate tissue‐engineered bone using human periosteal‐derived osteoblasts (PO) and polydioxanone/pluronic F127 (PDO/pluronic F127) scaffold with preseeded human periosteal‐derived CD146 positive endothelial‐like cells (PE). PE were purified from the periosteal cell population by cell sorting. One of the important factors to consider in generating tissue‐engineered bone using osteoprecursor and endothelial cells and a specific scaffold is whether the function of osteoprecursor and endothelial cells can be maintained in originally different culture medium conditions. After human PE were preseeded into PDO/pluronic F127 scaffold and cultured in endothelial cell basal medium‐2 for 7 days, human PO were seeded into the PDO/pluronic F127 scaffold with PE, and then, this cell‐scaffold construct was cultured in endothelial cell basal medium‐2 with osteogenic induction factors, including ascorbic acid, dexamethasone, and β‐glycerophosphate, for a further 7 days. Then, this 2‐week cultured construct was grafted into the mandibular defect of miniature pig. Twelve weeks after implantation, the animal was sacrificed. Clinical examination revealed that newly formed bone was seen more clearly in the defect with human PO and PDO/pluronic F127 scaffold with preseeded human PE. The experimental results suggest that tissue‐engineered bone formation using human PO and PDO/pluronic F127 scaffold with preseeded human PE can be used to restore skeletal integrity to various bony defects when used in clinics. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Viscoelastic behavior of poly(ether imide) incorporated with multiwalled carbon nanotubes
Authors: Shepard Kimberly B. , Gevgilili Halil , Ocampo Miguel , Li Jia , Fisher Frank T. , Kalyon Dilhan M.
Published: September 2012

There is significant potential in improving the mechanical, electrical, and thermal properties of engineering plastics, including poly(ether imide) (PEI), with various nanoinclusions such as multiwalled carbon nanotubes (MWCNTs). However, this potential can only be fully realized through a thorough understanding of the rheological behavior and the thermomechanical histories that the nanocomposites are exposed to during their preparation and the resulting effective properties. In this study, nanocomposites of PEI and MWCNTs were prepared using a solution processing method under different dispersion conditions, and the viscoelastic material functions of the nanocomposites were characterized as functions of concentration of CNTs in the 1–5% by weight range (volume fraction, ϕ = 0.006–0.03) and temperature. The storage modulus and magnitude of complex viscosity values of the PEI nanosuspensions increased by as much as 3500% and 800%, respectively, at ϕ = 0.03, along with similar orders of magnitude increases observed or predicted in other viscoelastic material functions. Such increases reflect how nanotube incorporation and network formation can drastically alter the flow and deformation behavior of the PEI/CNT nanosuspensions at processing‐relevant temperatures and deformation rates. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
Comparison of the Effects of Pelargonic Acid Vanillylamide and Capsaicin on Human Vanilloid Receptors
Authors: Weiser Thomas , Roufogalis Basil , Chrubasik Sigrun
Published: September 2012

Pelargonic acid vanillylamide is like capsaicin a natural capsaicinoid from chili peppers and commonly used in food additives to create a hot sensation, even in self‐defense pepper sprays and as an alternative to capsaicin in medical products for topical treatment of pain. Although the chemical structures of both compounds are similar, preclinical data suggest that capsaicin is the more potent compound. We therefore performed voltage‐clamp recordings using cells transfected with the human vanilloid receptor TRPV1 in order to assess the responses of pelargonic acid vanillylamide and capsaicin at the receptor level. We provide evidence that at the molecular target TRPV1, the concentration‐response curves, kinetics of current activation, as well as inhibition by the competitive antagonist capsazepine were not significantly different between the two capsaicinoids. We suggest that the different effects of the two capsaicinoids observed in previous studies may rather be due to different physicochemical or pharmacokinetic properties than to different pharmacological profiles at the receptor level. Copyright © 2012 John Wiley & Sons, Ltd.
5‐HT1B autoreceptor regulation of serotonin transporter activity in synaptosomes
Authors: Hagan Catherine E. , Mcdevitt Ross A. , Liu Yusha , Furay Amy R. , Neumaier John F.
Published: September 2012

Serotonin‐1B (5‐HT1B) autoreceptors are located in serotonin (5‐HT) terminals, along with serotonin transporters (SERT), and play a critical role in autoregulation of serotonergic neurotransmission and are implicated in disorders of serotonergic function, particularly emotional regulation. SERT modulates serotonergic neurotransmission by high‐affinity reuptake of 5‐HT. Alterations in SERT activity are associated with increased risk for depression and anxiety. Several neurotransmitter receptors are known to regulate SERT Km and Vmax, and previous work suggests that 5‐HT1B autoreceptors may regulate 5‐HT reuptake, in addition to modulating 5‐HT release and synthesis. We used rotating disk electrode voltammetry to investigate 5‐HT1B autoreceptor regulation of SERT‐mediated 5‐HT uptake into synaptosomes. The selective 5‐HT1B antagonist SB224289 decreased SERT activity in synaptosomes prepared from wild‐type but not 5‐HT1B knockout mice, whereas SERT uptake was enhanced after pretreatment with the selective 5‐HT1B agonist CP94253. Furthermore, SERT activity varies as a function of 5‐HT1B receptor expression—specifically, genetic deletion of 5‐HT1B decreased SERT function, while viral‐mediated overexpression of 5‐HT1B autoreceptors in rat raphe neurons increased SERT activity in rat hippocampal synaptosomes. Considered collectively, these results provide evidence that 5‐HT1B autoreceptors regulate SERT activity. Because SERT clearance rate varies as a function of 5‐HT1B autoreceptor expression levels and is modulated by both activation and inhibition of 5‐HT1B autoreceptors, this dynamic interaction may be an important mechanism of serotonin autoregulation with therapeutic implications. Synapse, 2012. © 2012 Wiley Periodicals, Inc.
Calibration of a burrow count index for the Indian desert jird, Meriones hurrianae
Authors: Ramesh Divya , Home Chandrima , Jhala Yadvendradev V. , Qureshi Qamar
Published: September 2012

Population estimates, often difficult to acquire, warrantee the use of an index as an economical substitute for rapid assessments of populations. We estimated population size of the little known social, semi‐fossorial Indian desert jird (Meriones hurrianae) in Kachchh, Gujarat, India under closed population capture‐mark‐recapture (CMR) framework to calibrate a burrow count index for the species. A total of 147 individuals were trapped in 16 colonies using baited Sherman traps and the number of burrow entrances at each colony was recorded. Data from colonies with low number of captures were pooled to estimate capture probability using Huggins heterogeneity models with gender, site, body weight and age category as covariates in Program MARK. Colony sizes ranged from 2 to 46 individuals. The number of burrow entrances was calibrated against CMR‐based population estimates using least squares regression (n = 16, adjusted R2 = 0.96, t = 18.18, P < 0.001). The index was further validated using Jackknife (JK) analysis where JK‐predicted population estimates strongly correlated with CMR estimates (r = 0.96, P < 0.001). In habitats and climatic conditions similar to Kachchh and within the range of colony sizes sampled, our calibrated index can be a valuable and effective tool for large scale surveys of the desert jird, which occupies a keystone trophic level in the semi‐arid ecosystem.
Cognitive Apartheid: On the Manner in Which High School Students Understand Evolution without Believing in Evolution
Authors: Hermann Ronald S.
Published: September 2012

High school science students are often unwilling to learn about evolution due to a perceived conflict with their religious beliefs. Other students are able to understand evolution despite the fact that they do not believe in evolution. According to Cobern (Sci Educ 80:579–610, 1996), students can wall off that which is believed from that which is not believed in a process he called cognitive apartheid. A mixed-methods study was conducted to determine the extent to which understanding of evolution differed among high school Advanced Placement science students who did and did not believe in evolution. Two students who demonstrate a sophisticated understanding of evolution despite their admonition that they do not believe in evolution were then interviewed. Eight themes emerged from the interview that provide insight into the views of students learning of evolution despite the fact that they do not believe in evolution. Based on these themes, several implications for the teaching of evolution are presented.
Lamine C2 et spermatogenèse
Authors: Courtot A. -M.
Published: September 2012

Les lamines A/C sont des filaments intermédiaires présents dans les noyaux des cellules. Leurs rôles sont multiples et des mutations du gène LMNA sont à l’origine de nombreuses maladies appelées laminopathies. Dans les cellules germinales masculines, cette famille de protéines n’est représentée que par la lamine C2. Les données obtenues chez la souris démontrent l’importance de ces filaments dans le déroulement de la méiose masculine et présagent de l’existence d’un nouveau domaine d’infertilité d’origine masculine lié à des mutations de ce filament intermédiaire ou de ses protéines associées.
Schizotypal traits in adolescents: Links to family history of psychosis and psychological distress
Authors: Cella M. , Serra M. , Lai A. , Mason O.J. , Sisti D. , Rocchi M.B.L. , Preti A. , Petretto D.R.
Published: September 2012

Objective

Studies in the general population report that unusual subjective experiences are relatively common. Such experiences have been conceptualized either as extreme personality traits or as vulnerability markers for psychosis, and often grouped under the expression “schizotypal experiences”. This study investigates the heterogeneity of schizotypal traits using factor and latent class analysis.

Methods

One thousand and thirty-two adolescents were recruited for this study. Schizotypal experiences were assessed with the Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE); psychological distress was assessed with the General Health Questionnaire (GHQ). Confirmatory Factorial Analysis (CFA) and Latent Class Analysis (LCA) were performed on the O-LIFE and on the association with the GHQ and demographic variables.

Results

CFA replicated the original 4-factor structure of the O-LIFE. Three latent classes (LC) of schizotypal features were identified: participants in LC1 (26% of the total sample) showed minimal level of item endorsement; LC2 accounted for 52% of the sample and showed overall higher item endorsement compared to LC1, especially for disorganization and positive signs of schizotypy, but not for negative affective items. LC3 (22%) showed an overall higher level of item endorsement across schizotypal dimensions, and positive association with psychological distress and family history of psychosis.

Discussion

Different latent class of schizotypal features can be empirically defined in adolescent community samples. The most extreme class is defined not only by a profile of higher positive replies to the items, but also by anhedonia, high psychological distress, and family history of psychosis. These findings can inform prevention research in schizophrenia.
PAK1 limits the expression of the pro‐apoptotic protein Bad in pancreatic islet β‐cells
Authors: Wang Zhanxiang , Thurmond Debbie C.
Published: September 2012

Human type 2 diabetes is associated with β‐cell apoptosis, and human islets from diabetic donors are ∼80% deficient in PAK1 protein. Toward addressing linkage of PAK1 to β‐cell survival, PAK1–siRNA targeted MIN6 pancreatic β‐cells were found to exhibit increased caspase‐3 cleavage, cytosolic cytochrome‐C and the pro‐apoptotic protein Bad. PAK1+/− heterozygous mouse islets recapitulated the upregulation of Bad protein expression, as did hyperglycemic treatment of human or mouse islets; Bad levels were exacerbated most in PAK1+/− islets subjected to hyperglycemic stress. These data implicate PAK1 in β‐cell survival via quenching of Bad protein expression, and suggest PAK1 as potential molecular target to preserve β‐cell mass.