bluuebunny/crossref_metadata_2025 huggingface dataset:
Biocompatibility Evaluation of Ionic‐ and Photo‐Crosslinked Methacrylated Gellan Gum Hydrogels: In Vitro and In Vivo Study
Authors: Silva‐Correia Joana , Zavan Barbara , Vindigni Vincenzo , Silva Tiago H. , Oliveira Joaquim M. , Abatangelo Giovanni , Reis Rui L.
Published: November 2012

In this study, the stability and biocompatibility of methacrylated gellan gum hydrogels, obtained either by ionic‐ (iGG‐MA) or photo‐crosslinking (phGG‐MA), were evaluated in vitro and in vivo. Size exclusion chromatography analysis of the methacrylated gellan gum (GG‐MA) powder revealed that molecular weight is lower as compared to the non‐modified material, i.e., low acyl gellan gum. The water uptake and swelling of iGG‐MA and phGG‐MA hydrogels were investigated in phosphate‐buffered saline solution (pH 7.4). The biocompatibility of the hydrogels was firstly evaluated by producing cell‐laden hydrogels. The in vitro cells encapsulation study showed that lung fibroblast cells (L929 cells) and human intervertebral disc (hIVD) cells are viable when cultured within both hydrogels, up to 21 days of culturing. The iGG‐MA and phGG‐MA hydrogels were also subcutaneously implanted in Lewis rats for 10 and 18 days. Tissue response to the hydrogels implantation was determined by histological analysis (haematoxylin‐eosin staining). A thin fibrous capsule was observed around the implanted hydrogels. No necrosis, calcification, and acute inflammatory reaction were observed. The results presented in this study demonstrate that iGG‐MA and phGG‐MA hydrogels are stable in vitro and in vivo, support L929 and hIVD cells’ encapsulation and viability, and were found to be well‐tolerated and non‐toxic in vivo.
Nutritional composition of actual and potential insect prey for the Kasekela chimpanzees of Gombe National Park, Tanzania
Authors: O'Malley Robert C. , Power Michael L.
Published: October 2012

Humans, all great ape species, and some lesser apes consume insects. Insects can provide comparable nutritional yields to meat on a gram‐for‐gram basis and may serve as an important source of energy, fat, protein, minerals, and vitamins for hominoids. Although potential insect prey are abundant in ape habitats, patterns of insectivory are not consistent across species or populations. Efforts to understand these patterns are complicated by a lack of nutritional data. We collected samples of insects consumed by the Kasekela chimpanzee community of Gombe National Park, Tanzania, as well as of some insects found within the community range and ignored by these chimpanzees but known to be preyed upon byPanelsewhere. We determined the gross energy (GE), estimated metabolizable energy (ME), fat, protein, fiber, and ash content of these samples following standard methodologies. We use these data to test the hypothesis that Kasekela chimpanzees choose insect prey (at least in part) based on energy and/or macronutrient content. On a fresh‐weight, per‐gram basis, the insect prey consumed by Kasekela chimpanzees had significantly higher fat and lower ash content than other assayed insects, and on a fresh‐weight, per‐foraging‐unit (“per‐insect,” “per‐dip,” or “per‐nest”) basis were significantly higher in GE, fat, and protein. On a per‐gram basis, the assayed insects were generally comparable in energy and macronutrients to wild vertebrate meat. We conclude that Kasekela chimpanzees do favor insects that are high in energy, fat, and protein, and that the potential macronutrient yields from some forms of insectivory are not trivial. © 2012 Wiley Periodicals, Inc.
An exploration of fixed and random effects selection for longitudinal binary outcomes in the presence of nonignorable dropout
Authors: Li Ning , Daniels Michael J. , Li Gang , Elashoff Robert M.
Published: November 2012

We explore a Bayesian approach to selection of variables that represent fixed and random effects in modeling of longitudinal binary outcomes with missing data caused by dropouts. We show via analytic results for a simple example that nonignorable missing data lead to biased parameter estimates. This bias results in selection of wrong effects asymptotically, which we can confirm via simulations for more complex settings. By jointly modeling the longitudinal binary data with the dropout process that possibly leads to nonignorable missing data, we are able to correct the bias in estimation and selection. Mixture priors with a point mass at zero are used to facilitate variable selection. We illustrate the proposed approach using a clinical trial for acute ischemic stroke.
Sacral nerve stimulation for constipation
Authors: Thomas G P , Dudding T C , Rahbour G , Nicholls R J , Vaizey C J
Published: November 2012

Background

For over 10 years sacral nerve stimulation (SNS) has been used for patients with constipation resistant to conservative treatment. A review of the literature is presented.

Methods

PubMed, MEDLINE and Embase databases were searched for studies demonstrating the use of SNS for the treatment of constipation.

Results

Thirteen studies have been published describing the results of SNS for chronic constipation. Of these, three were in children and ten in adults. Test stimulation was successful in 42–100 per cent of patients. In those who proceeded to permanent SNS, up to 87 per cent showed an improvement in symptoms at a median follow-up of 28 months. The success of stimulation varied depending on the outcome measure being used. Symptom improvement correlated with improvement in quality of life and patient satisfaction scores.

Conclusion

SNS appears to be an effective treatment for constipation, but this needs to be confirmed in larger prospective studies with longer follow-up. Improved outcome measures need to be adopted given the multiple symptoms that constipation may be associated with. Comparison with other established surgical therapies also needs consideration.
Multicentre European study of preoperative biliary drainage for hilar cholangiocarcinoma
Authors: Farges O , Regimbeau J M , Fuks D , Le Treut Y P , Cherqui D , Bachellier P , Mabrut J Y , Adham M , Pruvot F R , Gigot J F
Published: November 2012

Background

Indications for preoperative biliary drainage (PBD) in the context of hepatectomy for hilar malignancies are still debated. The aim of this study was to investigate current European practice regarding biliary drainage before hepatectomy for Klatskin tumours.

Methods

This was a retrospective analysis of all patients who underwent formal or extended right or left hepatectomy for hilar cholangiocarcinoma between 1997 and 2008 at 11 European teaching hospitals, and for whom details of serum bilirubin levels at admission and at the time of surgery were available. PBD was performed at the physicians' discretion. The primary outcome was 90-day mortality. Secondary outcomes were morbidity and cause of death. The association of PBD and of preoperative serum bilirubin levels with postoperative mortality was assessed by logistic regression, in the entire population as well as separately in the right- and left-sided hepatectomy groups, and was adjusted for confounding factors.

Results

A total of 366 patients were enrolled; PBD was performed in 180 patients. The overall mortality rate was 10·7 per cent and was higher after right- than left-sided hepatectomy (14·7 versus 6·6 per cent; adjusted odds ratio (OR) 3·16, 95 per cent confidence interval 1·50 to 6·65; P = 0·001). PBD did not affect overall postoperative mortality, but was associated with a decreased mortality rate after right hepatectomy (adjusted OR 0·29, 0·11 to 0·77; P = 0·013) and an increased mortality rate after left hepatectomy (adjusted OR 4·06, 1·01 to 16·30; P = 0·035). A preoperative serum bilirubin level greater than 50 µmol/l was also associated with increased mortality, but only after right hepatectomy (adjusted OR 7·02, 1·73 to 28·52; P = 0·002).

Conclusion

PBD does not affect overall mortality in jaundiced patients with hilar cholangiocarcinoma, but there may be a difference between patients undergoing right-sided versus left-sided hepatectomy.
Enhancement of Turbulent Flow Heat Transfer in a Tube with Modified Twisted Tapes
Authors: Lei Y. G. , Zhao C. H. , Song C. F.
Published: November 2012

Numerical simulations were performed to study the fluid flow and heat transfer in a tube with staggered twisted tapes with central holes. In the range of Reynolds numbers between 6000 and 28 000, the modified twisted tapes increased the Nusselt number by 76.2 ∼ 149.7 % and the friction factor by 380.2 ∼ 443.8 % compared to the smooth tube. Compared to the typical twisted tapes, the modified twisted tapes produced an acceleration flow through the triangle regions leading to the enhancement of heat transfer, and the holes in the modified tapes reduced the severe pressure loss. It was found that the modified twisted tapes decreased the friction factor by 8.0 ∼ 16.1 % and enhanced the heat transfer by 34.1 ∼ 46.8 % in comparison with the typical tapes. These results indicated that the performance ratio values of the tube with modified twisted tapes were higher than 1.0 in the range of Reynolds numbers studied. The computed performance ratios of the tube with modified twisted tapes were much higher than those of the tube with typical twisted tapes. This means that the integrated performance of the tube with staggered twisted tapes with central holes is superior to that of the tube with typical twisted tapes.
A Concise Domino Synthesis of Benzo‐1,4‐heterocycle Compounds via a Piancatelli/C–N Coupling/Michael Addition Process Promoted by La(OTf)3
Authors: Liu Jinqian , Shen Qiang , Yu Jianjun , Zhu Mengyun , Han Jianwei , Wang Limin
Published: November 2012

A La(OTf)3‐catalyzed domino method has been developed to synthesize the cis‐1,4‐benzoxazine derivatives from 2‐furylcarbinols 1 and o‐aminophenol derivatives, by a Piancatelli/C–N coupling/Michael addition process. A wide array of substrates could be used to give the desired products in good yields. Since this method involves simple reaction conditions and short reaction times, and has a broad substrate scope, it is particularly attractive for the efficient development of libraries of biologically relevant 1,4‐benzoxazine derivatives. Furthermore, a similar strategy was also successfully applied to form 1,2,3,4‐tetrahydroquinoxaline derivatives from 1 and N‐substituted o‐diaminobenzenes.
A preliminary study on leachability of chromium from a contaminated site
Authors: Kanchinadham Sri Bala Kameswari , Loganathan Vidhya Devi , Kalyanaraman Chitra
Published: October 2012

In the present article, chromite ore processing residue (COPR) and soil samples were collected from a chromium contaminated site in Tamil Nadu State, India. Around 155.02 and 28.01 mg g−1 of Cr(VI) was present in COPR and soil samples, respectively. Leachability studies were carried out to assess the leachability of Cr(VI) and Cr(III) from COPR and soil samples following the toxicity characteristic leaching procedure (TCLP) test protocol using (i) acetic acid and (ii) water as leaching medium. Cr(VI) had leached out in both the mediums, whereas Cr(III) leached only in acetic acid as leaching medium since Cr(III) is insoluble at pH > 6. TCLP test results are requisite to assess the extent of leaching of chromium from the contaminated soil or COPR and are a helpful tool for implementation of remediation measures to avoid further contamination. © 2012 American Institute of Chemical Engineers Environ Prog, 32: 1096–1100, 2013
Reliability and validity of a continuous pain registration procedure
Authors: van Wijk A.J. , Lobbezoo F. , Hoogstraten J.
Published: October 2012

Background

Conventional pain rating scales [i.e. visual analogue scales (VAS) or numerical rating scales (NRS)] only provide a summary for different levels of pain felt, while the duration of these levels is not accounted for. If pain can be rated continuously, the area under the curve (AUC) of varying pain intensity over time can be calculated, which integrates varying pain intensity with duration. The present study examined the reproducibility and validity of a continuous pain rating procedure.

Methods

Twenty‐eight healthy volunteers participated. Pain was induced using constant current delivered to the non‐dominant forearm using bipolar electrodes. Pain was rated continuously on an electronic VAS monitored by a computer. For each participant, the level of current needed to achieve a weak, mild, slightly moderate and moderate level of pain was determined (part I). Next, participants were asked to rate the painfulness of six periods of electrical stimulation (part II). Unknown to the participants, they were presented with the four levels of current obtained in part I, where the level of current for mild and moderate pain was presented twice (in order to assess consistency). The order of presentation was randomized for all subjects.

Results

In general, participants produced reliable mean AUCs. In addition, the AUC of pain intensity over time could clearly discriminate between the four levels of pain used in the present study.

Discussion

A continuous pain registration procedure, using an AUC approach, may be a promising direction to explore. Results can be improved by allowing more training on the use of the electronic VAS.
Phase composition control of calcium phosphate nanoparticles for tunable drug delivery kinetics and treatment of osteomyelitis. II. Antibacterial and osteoblastic response
Authors: Uskoković Vuk , Desai Tejal A.
Published: October 2012

Osteomyelitis has been traditionally treated by the combination of long‐term antibiotic therapies and surgical removal of diseased tissue. The multifunctional material was developed in this study with the aim to improve this therapeutic approach by: (a) enabling locally delivered and sustained release of antibiotics at a tunable rate, so as to eliminate the need for repetitive administration of systemically distributed antibiotics; and (b) controllably dissolving itself, so as to promote natural remineralization of the portion of bone lost to disease. We report hereby on the effect of previously synthesized calcium phosphates (CAPs) with tunable solubilities and drug release timescales on bacterial and osteoblastic cell cultures. All CAP powders exhibited satisfying antibacterial performance against Staphylococcus aureus, the main causative agent of osteomyelitis. Still, owing to its highest drug adsorption efficiency, the most bacteriostatically effective phase was amorphous CAP with the minimal inhibitory concentration of less than 1 mg/mL. At the same time, the positive cell response and osteogenic effect of the antibiotic‐loaded CAP particles was confirmed in vitro for all the sparsely soluble CAP phases. Adsorption of the antibiotic onto CAP particles reversed the deleterious effect that the pure antibiotic exerted on the osteogenic activity of the osteoblastic cells. The simultaneous osteogenic and antimicrobial performance of the material developed in this study, altogether with its ability to exhibit sustained drug release, may favor its consideration as a material base for alternative therapeutic approaches to prolonged antibiotic administration and surgical debridement typically prescribed in the treatment of osteomyelitis. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Mineralized poly(lactic acid) scaffolds loading vascular endothelial growth factor and the in vivo performance in rat subcutaneous model
Authors: Kim Joong‐Hyun , Kim Tae‐Hyun , Jin Guang‐Zhen , Park Jeong‐Hui , Yun Ye‐Rang , Jang Jun‐Hyeog , Kim Hae‐Won
Published: October 2012

The functionalization of degradable polymeric scaffolds with therapeutic molecules such as vascular endothelial growth factor (VEGF) is a key strategy to gain better regenerative ability of damaged bone tissue by stimulating vascularization and tissue perfusion. Here, we combined VEGF with poly(lactic acid) (PLA) porous scaffold, after modifying the PLA surface with calcium phosphate (CaP) mineral. The mineralized PLA scaffold (mPLA) showed more effective loading capacity of VEGF than the PLA without mineralization as well as profiled sustainable release of VEGF for up to a couple of weeks. The VEGF‐loaded mPLA scaffold presented significantly improved proliferation of primary endothelial cells for up to 7 days, with respect to the scaffold without the VEGF loading. The performance of the engineered scaffold was assessed after subcutaneous implantation in rats for 4 weeks. Histological results showed favorable tissue compatibility of both the mPLA scaffolds (with and without VEGF loading), as characterized by infiltration of inflammatory cells, formation of fibrous capsule, and ingrowth of fibroblasts into the matrices. Immunohistochemical staining of the von Willebrand Factor revealed significantly improved formation of neo‐capillaries in the VEGF‐loaded mPLA. Based on this study, the strategy of VEGF loading onto mineralized PLA scaffold is considered beneficial for gaining improved vascularization of the polymeric scaffolds, suggesting potential applications for bone tissue engineering. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2013.
Biocompatibility and strength retention of biodegradable Mg‐Ca‐Zn alloy bone implants
Authors: Cho Sung Youn , Chae Soo‐Won , Choi Kui Won , Seok Hyun Kwang , Kim Yu Chan , Jung Jae Young , Yang Seok Jo , Kwon Gyeong Je , Kim Jong Tack , Assad Michel
Published: October 2012

The biocompatibility and strength retention of a Mg‐Ca‐Zn alloy were studied to evaluate its efficacy for osteosynthesis applications. Mg‐Ca‐Zn alloy and self‐reinforced poly l‐lactide (SR‐PLLA) bone screws were implanted into New Zealand rabbits for radiography analysis, micro computed tomography analysis, histomorphometry, hematology, serum biochemistry, histopathology, and inductively coupled plasma mass spectrometry analysis. Bending and torsion tests were performed on intact specimens to find the initial mechanical strength of these Mg‐Ca‐Zn alloy bone screws. Strength retention of the Mg‐Ca‐Zn alloy implants were calculated from in vivo degradation rates and initial mechanical strength. Based on the animal study, Mg‐Ca‐Zn alloy bone screw showed absence of subcutaneous gas pockets, characteristic surface erosion properties, faster degradation rate than SR‐PLLA bone screw, normal reference range of hematology and serum biochemistry, better histopathological response than SR‐PLLA bone screw, and stable concentrations of each constituent element in soft tissues surrounding the implants. The initial strength and strength retention of Mg‐Ca‐Zn alloy were compared with those of various biomaterials. The initial strength of Mg‐Ca‐Zn alloy was higher than those of biostable and biodegradable polymers. The strength retention of Mg‐Ca‐Zn alloy bone screws was similar to those of biodegradable polymer. Therefore, this Mg‐Ca‐Zn alloy represents an excellent biodegradable biomaterial candidate for osteosynthesis applications. © 2012 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2013.
STAAR: Statistical analysis of aromatic rings
Authors: Jenkins David D. , Harris Jason B. , Howell Elizabeth E. , Hinde Robert J. , Baudry Jerome
Published: October 2012

The statistical analysis of aromatic rings program allows for an automated search for anion‐π interactions between phenylalanine residues and carboxylic acid moieties of neighboring aspartic acid or glutamic acid residues in protein data bank (PDB) structures. The program is written in C++ and is available both as a standalone code and through a web implementation that allows users to upload and analyze biomolecular structures in PDB format. The program outputs lists of Phe/Glu or Phe/Asp pairs involved in potential anion‐π interactions, together with geometrical (distance and angle between the Phe's center of mass and Glu or Asp's center of charge) and energetic (quantum mechanical Kitaura‐Morokuma interaction energy between the residues) descriptions of each anion‐π interaction. Application of the program on the latest content of the PDB shows that anion‐π interactions are present in thousands of protein structures and can possess strong energies, as low as −8.72 kcal/mol. © 2012 Wiley Periodicals, Inc.
Quantification of left ventricular indices from SSFP cine imaging: Impact of real‐world variability in analysis methodology and utility of geometric modeling
Authors: Miller Christopher A. , Jordan Peter , Borg Alex , Argyle Rachel , Clark David , Pearce Keith , Schmitt Matthias
Published: November 2012

Purpose:

To assess the impact of “real‐world” practice variation in the process of quantifying left ventricular (LV) mass, volume indices, and ejection fraction (EF) from steady‐state free precession cardiovascular magnetic resonance (CMR) images. The utility of LV geometric modeling techniques was also assessed.

Materials and Methods:

The effect of short‐axis‐ versus long‐axis‐derived LV base identification, simplified versus detailed endocardial contouring, and visual versus automated identification of end‐systole were evaluated using CMR images from 50 consecutive, prospectively recruited patients. Additionally, the performance of six geometric models was assessed. Repeated measurements were performed on 25 scans (50%) in order to assess observer variability.

Results:

Simplified endocardial contouring significantly overestimated volumes and underestimated EF (–6 ± 4%, P < 0.0005) compared to detailed contouring. A mean difference of –34g (P < 0.0005) was observed between mass measurements made using short‐axis‐ versus long‐axis‐derived LV base positioning. A technique involving long‐axis LV base identification, signal threshold‐based detailed endocardial contouring, and automated identification of end‐systole had significantly higher observer agreement. Geometric models showed poor agreement with conventional analysis and high variability.

Conclusion:

Real‐world variability in CMR image analysis leads to significant differences in LV mass, volume and EF measurements, and observer variability. Appropriate reference ranges should be applied. Use of geometric models should be discouraged. J. Magn. Reson. Imaging 2013;37:1213–1222. © 2012 Wiley Periodicals, Inc.
On periodic Hamiltonian elliptic systems with spectrum point zero
Authors: Sun Juntao , Chen Haibo , Chu Jifeng
Published: October 2012

In this paper, we study the existence and multiplicity of solutions for a class of periodic Hamiltonian elliptic systems with spectrum point zero. By applying two recent critical point theorems for strongly indefinite functionals, we present some new criteria to guarantee that Hamiltonian elliptic systems with spectrum point zero have a ground state solution and infinitely many geometrically distinct solutions when the potential satisfies the asymptotically quadratic and weak superquadratic conditions, respectively. Some recent results are extended and improved.
Seizures in juvenile Huntington's disease: Frequency and characterization in a multicenter cohort
Authors: Cloud Leslie J. , Rosenblatt Adam , Margolis Russel L. , Ross Christopher A. , Pillai Jagan A. , Corey‐Bloom Jody , Tully Hannah M. , Bird Thomas , Panegyres Peter K. , Nichter Charles A. , Higgins Donald S. , Helmers Sandra L. , Factor Stewart A. , Jones Randi , Testa Claudia M.
Published: November 2012

Little is known about the epilepsy that often occurs in the juvenile form of Huntington's disease (HD), but is absent from the adult‐onset form. The primary aim of this study was to characterize the seizures in juvenile HD (JHD) subjects with regard to frequency, semiology, defining EEG characteristics, and response to antiepileptic agents. A multicenter, retrospective cohort was identified by database query and/or chart review. Data on age of HD onset, primary HD manifestations, number of CAG repeats, the presence or absence of seizures, seizure type(s), antiepileptic drugs used, subjects' response to antiepileptic drugs (AEDs), and EEG results were assembled, where available. Ninety subjects with genetically confirmed JHD were included. Seizures were present in 38% of subjects and were more likely to occur with younger ages of HD onset. Generalized tonic‐clonic seizures were the most common seizure type, followed by tonic, myoclonic, and staring spells. Multiple seizure types commonly occurred within the same individual. Data on EEG findings and AED usage are presented. Seizure risk in JHD increases with younger age of HD onset. Our ability to draw firm conclusions about defining EEG characteristics and response to AEDs was limited by the retrospective nature of the study. Future prospective studies are required. © 2012 Movement Disorder Society
Progression of cortical thinning in early Parkinson's disease
Authors: Ibarretxe‐Bilbao Naroa , Junque Carme , Segura Barbara , Baggio Hugo C. , Marti Maria J. , Valldeoriola Francesc , Bargallo Nuria , Tolosa Eduardo
Published: November 2012

The aim of this study was to investigate the progression of cortical thinning and gray‐matter (GM) volume loss in early Parkinson's disease (PD). MRI and neuropsychological assessment were obtained at baseline and follow‐up (mean ± standard deviation = 35.50 ± 1.88 months) in a group of 16 early‐PD patients (H & Y stage ≤II and disease duration ≤5 years) and 15 healthy controls matched for age, gender, and years of education. FreeSurfer software was used for the analysis of cortical thickness as well as for cortical and subcortical volumetric analyses. Voxel‐based morphometry analysis was performed using SPM8. Compared to controls, PD patients showed greater regional cortical thinning in bilateral frontotemporal regions as well as greater over‐time total GM loss and amygdalar volume reduction. PD patients and controls presented similar over‐time changes in cognitive functioning. In early‐PD patients, global GM loss, amygdalar atrophy, and cortical thinning in frontotemporal regions are specifically associated with the PD‐degenerative process. © 2012 Movement Disorder Society
Does MPTP intoxication in mice induce metabolite changes in the nucleus accumbens? A 1H nuclear MRS study
Authors: Chassain Carine , Bielicki Guy , Carcenac Carole , Ronsin Anne‐Claire , Renou Jean‐Pierre , Savasta Marc , Durif Franck
Published: October 2012

Using in vivo 1H NMR spectroscopy in a mouse model of Parkinson's disease, we previously showed that glutamate concentrations in the dorsal striatum were highest after dopamine denervation associated with an increase in gamma‐aminobutyric acid (GABA) and (Gln) glutamine levels. The aim of this study was to determine whether the changes previously observed in the motor part of the striatum were reproduced in a ventral part of the striatum, the nucleus accumbens (NAc). This study was carried out on controls and 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP)‐intoxicated mice. In vivo spectra were acquired for a voxel (8 μL) in the dorsal striatum, and in the NAc (1.56 μL). NMR acquisitions were first performed 10 days after the last MPTP injection in a basal condition [after saline intraperitoneal (i.p.) injection] and then in the same animal the week after basal NMR acquisitions, after acute levodopa administration (200 mg kg–1, i.p.). Immunohistochemistry was used to determine the levels of (Glu) glutamate, glutamine synthetase (GS) and glutamic acid decarboxylase (GAD) isoform 67 in these two structures. The Glu, Gln and GABA concentrations obtained in the basal state were higher in the NAc of MPTP‐intoxicated mice which have the higher dopamine denervation in the ventral tegmental area (VTA) and in the dorsal striatum. Levodopa decreased the levels of these metabolites in MPTP‐intoxicated mice to levels similar to those in controls. In parallel, immunohistochemical staining showed that glutamate, GS and GAD67 immunoreactivity increased in the dorsal striatum of MPTP‐intoxicated mice and in the NAc for animals with a severe dopamine denervation in VTA. These findings strongly supported a hyperactivity of the glutamatergic cortico‐striatal pathway and changes in glial activity when the dopaminergic denervation in the VTA and substantia nigra pars compacta (SNc) was severe. Copyright © 2012 John Wiley & Sons, Ltd.
Characterization and electrical properties of honeycomb‐patterned poly(ε‐caprolactone)/reduced graphene oxide composite film
Authors: Thinh Phung Xuan , Basavajara C. , Kim Jin Kyoung , Huh Do Sung
Published: October 2012

A novel biocompatible composite of poly(ε‐caprolactone) (PCL) was synthesized via in situ ring‐opening polymerization method of ε‐caprolactone in the presence of reduced graphene oxide (RGO). Fourier transform infrared (FTIR) and X‐ray photoelectron spectroscopy (XPS) studies support a strong interaction between PCL and RGO. The crystallization behavior and thermal stability of these composites were studied using differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. Honeycomb‐patterned thin films with regular structures were fabricated by casting the composite solution under humid conditions. The temperature‐dependent DC conductivity of the honeycomb‐patterned composite films was studied in the range of 290−330 K, which revealed a semiconducting behavior in the transport properties of the composite films. DC conductivity of the patterned films was increased by increasing the concentration of RGO in the composites and in the increased temperature. POLYM. COMPOS., 2012. © 2012 Society of Plastics Engineers
Nonisothermal crystallization kinetics of poly(lactide)—effect of plasticizers and nucleating agent
Authors: Courgneau Cécile , Ducruet Violette , Avérous Luc , Grenet Jean , Domenek Sandra
Published: October 2012

Poly(lactide), a bio‐based aliphatic polyester, is a subject to large research effort. One point of optimization is the acceleration of its crystallization kinetics to promote crystallinity under nonisothermal polymer processing conditions by means of compounding with nucleating agents and plasticizers. The nonisothermal crystallization kinetics of neat and formulated poly(L,D‐lactide) (PDLLA) from the melt with talc and polyethylene glycol (PEG) or acetyl tributyl citrate (ATBC) were studied with the help of the Avrami–Jeziorny and Liu–Mo analysis. Talc showed to be a moderately efficient nucleating agent, as it causes only small increase of crystallization kinetics and shows no effect on the crystallization activation energy. A synergistic effect with plasticizers was observed, expanding the crystallization window significantly. PEG was found to be a more efficient plasticizer than ATBC but causes large decrease in the molecular weight average of PDLLA upon thermal treatment. The talc/ATBC system is efficient starting with an ATBC concentration of 9 wt%. The acceleration observed was a crystallization half‐time decrease of 30% compared to neat PLA and reaching maximum crystallization enthalpies even at cooling rate of 25°C min−1. The ATBC/talc system can be recommended as an efficient system for acceleration of nonisothermal crystallization kinetics of PDLLA. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers
Stereoregular poly‐O‐methyl [m,n]‐polyurethanes derived from D‐mannitol
Authors: Fidalgo Daniela M. , Kolender Adriana A. , Varela Oscar
Published: October 2012

Novel linear carbohydrate‐derived [m,n]‐polyurethanes are successfully prepared using D‐mannitol as renewable and low cost starting material. The key comonomer, 1,6‐di‐O‐phenylcarbonyl‐2,3,4,5‐tetra‐O‐methyl‐D‐mannitol is polymerized with a diamine synthesized from D‐mannitol or with alkylenediamines. These polymerization reactions afford, respectively, a [6,6]‐polyurethane entirely based on a carbohydrate derivative or [m,n]‐polyurethanes constituted by a poly‐O‐methyl substituted unit alternating with a polymethylene chain. All these polymers are stereoregular, as result of the C2 axis of symmetry of mannitol. The optically active polyurethanes are characterized by standard methods (FTIR, RMN, GPC, TGA, and DSC). Thus, GPC analysis reveals weight‐average molecular weights between 18,000 and 25,000 Da. Thermal studies (DSC) indicate that the polymers obtained are amorphous materials with Tg values dependent on the structure and chain length of the diamine constituent. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013
Solution‐processable colorless polyimides derived from hydrogenated pyromellitic dianhydride with controlled steric structure
Authors: Hasegawa Masatoshi , Hirano Daiki , Fujii Mari , Haga Misako , Takezawa Eiichiro , Yamaguchi Shinya , Ishikawa Atsushi , Kagayama Takashi
Published: October 2012

This work presents novel colorless polyimides (PIs) derived from 1R,2S,4S,5R‐cyclohexanetetracarboxylic dianhydride (H″‐PMDA). Isomer effects were also discussed by comparing with PI systems derived from conventional hydrogenated pyromellitic dianhydride, that is, 1S,2R,4S,5R‐cyclohexanetetracarboxylic dianhydride (H‐PMDA). H″‐PMDA was much more reactive with various diamines than H‐PMDA, and the former led to PI precursors with much higher molecular weights. The results can be explained from the quite different steric structures of these isomers. The thermally imidized H″‐PMDA‐based films were colorless regardless of diamines because of inhibited charge‐transfer interaction. In particular, the H″‐PMDA/4,4′‐oxydianiline system simultaneously achieved a very high Tg exceeding 300 °C, high toughness (elongation at break > 70%), and good solution processability. In contrast, the H‐PMDA‐based counterparts were essentially insoluble. The outstanding solubility of the former probably results from disturbed chain stacking by its nonplanar steric structure. An advantage of chemical imidization process is also proposed. In some cases, a copolymerization approach with an aromatic tetracarboxylic dianhydride was effective to improve the thermal expansion property. The results suggest that the H″‐PMDA‐based PI systems can be promising candidates for novel high‐temperature plastic substrate materials in electronic paper displays. A potential application as optical compensation film materials in liquid crystal displays (LCD) is also proposed in this work. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013
Depth characterization by confocal raman microscopy of oxygen inhibition in free radical photopolymerization of acrylates: Contribution of the thiol chemistry
Authors: Courtecuisse François , Cerezo Javier , Croutxé‐Barghorn Céline , Dietlin Céline , Allonas Xavier
Published: October 2012

The oxygen inhibition of acrylate photopolymerization using visible light was depth characterized by confocal Raman microscopy. The sample thickness was found to influence the depth conversion profile. With increasing sample thickness, the conversion at the surface was increased and the oxygen‐affected layer (OAL) decreased, up to a limit where the profiles became independent of the thickness. The addition of a thiol in the acrylate mixture reduced the OAL and the conversion in this region increased. This effect was noticeable even at low concentration of thiol. Real‐time infrared spectroscopy (RT‐FTIR) experiments pointed out that for low thiol content, this beneficial effect is not only attributable to the thiol–ene process—oxygen insensitive—but also to the homopolymerization of acrylates which is enhanced. Homopolymerization and thiyl radical addition were found to have the same impact on the overall mechanism. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013
Rate‐ and temperature‐dependent strain softening in solid polymers
Authors: van Breemen Lambert C. A. , Engels Tom A. P. , Klompen Edwin T. J. , Senden Dirk J. A. , Govaert Leon E.
Published: October 2012

It is demonstrated that a large number of solid polymers (PMMA, PLLA, iPP, PS) display a pronounced change in kinetics (strain‐rate and temperature dependence) after yield. The phenomenon finds its origin in the fact that, in specific ranges of temperature and strain rate, two different molecular processes may contribute to the yield stress. Because of strain softening, the post‐yield response is only controlled by one of the two, resulting in a strain‐rate dependence of the yield drop. The universality of the phenomenon is discussed in connection to the alleged influence of secondary transitions on the impact response of polymer glasses. A modification of the finite‐strain elasto‐viscoplastic EGP‐model is proposed to enable an accurate description of the mechanical response of solid polymers in the transition range. The versatility of the model is demonstrated on the temperature and strain‐rate dependence of the intrinsic mechanical behavior of PMMA, iPP, PS, and PLLA. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012
Analysis of multicentre trials with continuous outcomes: when and how should we account for centre effects?
Authors: Kahan Brennan C. , Morris Tim P.
Published: October 2012

In multicentre trials, randomisation is often carried out using permuted blocks stratified by centre. It has previously been shown that stratification variables used in the randomisation process should be adjusted for in the analysis to obtain correct inference. For continuous outcomes, the two primary methods of accounting for centres are fixed‐effects and random‐effects models. We discuss the differences in interpretation between these two models and the implications that each pose for analysis. We then perform a large simulation study comparing the performance of these analysis methods in a variety of situations. In total, we assessed 378 scenarios. We found that random centre effects performed as well or better than fixed‐effects models in all scenarios. Random centre effects models led to increases in power and precision when the number of patients per centre was small (e.g. 10 patients or less) and, in some scenarios, when there was an imbalance between treatments within centres, either due to the randomisation method or to the distribution of patients across centres. With small samples sizes, random‐effects models maintained nominal coverage rates when a degree‐of‐freedom (DF) correction was used. We assessed the robustness of random‐effects models when assumptions regarding the distribution of the centre effects were incorrect and found this had no impact on results. We conclude that random‐effects models offer many advantages over fixed‐effects models in certain situations and should be used more often in practice. Copyright © 2012 John Wiley & Sons, Ltd.
Considerations on covariates and endpoints in multi‐arm multi‐stage clinical trials selecting all promising treatments
Authors: Jaki T. , Magirr D.
Published: October 2012

In early stages of drug development, there is often uncertainty about the most promising among a set of different treatments. To ensure the best use of resources in such situations, it is important to decide which, if any, of the treatments should be taken forward for further testing. In later development, it has been shown that evaluating more than one dose increases the chance of success substantially. In this work, we discuss how multi‐arm multi‐stage trials can be designed such that all promising treatments are kept in the study at the interim analyses. We first investigate the impact of deviating from the planned design and show how confidence intervals can be constructed before we consider the impact of important covariates. We show that under orthogonality, the inclusion of covariates has no effect on familywise error rate control in the strong sense. We further show that the derived methodology can be used to investigate non‐normal endpoints. Copyright © 2012 John Wiley & Sons, Ltd.
A Joint Experimental and Computational Search for Authentic Nano‐electrocatalytic Effects: Electrooxidation of Nitrite and L‐Ascorbate on Gold Nanoparticle‐Modified Glassy Carbon Electrodes
Authors: Wang Ying , Ward Kristopher R. , Laborda Eduardo , Salter Chris , Crossley Alison , Jacobs Robert M. J. , Compton Richard G.
Published: November 2012

The investigation of electrocatalytic nanoeffects is tackled via joint electrochemical measurements and computational simulations. The cyclic voltammetry of electrodes modified with metal nanoparticles is modeled considering the kinetics of the electrochemical process on the bulk materials of the different regions of the electrode, that is, the substrate (glassy carbon) and the nanoparticles (gold). Comparison of experimental and theoretical results enables the detection of changes in the electrode kinetics at the nanoscale due to structural and/or electronic effects. This approach is applied to the experimental assessment of electrocatalytic effects by gold nanoparticles (Au NPs) in the electrooxidation of nitrite and L‐ascorbate. Glassy carbon electrode is modified with Au NPs via seed‐mediated growth method. Divergence between the kinetics of these processes on gold macroelectrodes and gold nanoparticles is examined. Whereas claimed catalytic effects are not observed in the electrooxidation of nitrite, electrocatalytic nanoeffects are verified in the case of L‐ascorbate. This is probably due to that the electron transfer process follows an adsorptive mechanism. The combination of simulation with experiments is commended as a general strategy of authentification, or not, of nanoelectrocatalytic effects.
Artificial Spores: Cytocompatible Encapsulation of Individual Living Cells within Thin, Tough Artificial Shells
Authors: Yang Sung Ho , Hong Daewha , Lee Juno , Ko Eun Hyea , Choi Insung S.
Published: November 2012

Cells are encapsulated individually within thin and tough shells in a cytocompatible way, by mimicking the structure of bacterial endospores that survive under hostile conditions. The 3D ‘cell‐in‐shell’ structures—coined as ‘artificial spores'—enable modulation and control over cellular metabolism, such as control of cell division, resistance to external stresses, and surface‐functionalizability, providing a useful platform for applications, including cell‐based sensors, cell therapy, regenerative medicine, as well as for fundamental studies on cellular metabolism at the single‐cell level and cell‐to‐cell communications. This Concept focuses on chemical approaches to single‐cell encapsulation with artificial shells for creating artificial spores, including cross‐linked layer‐by‐layer assembly, bioinspired mineralization, and mussel‐inspired polymerization. The current status and future prospects of this emerging field are also discussed.
The UTfit collaboration average of D meson mixing data: spring 2012
Authors: Bevan A. J. , Bona M. , Ciuchini M. , Derkach D. , Franco E. , Lubicz V. , Martinelli G. , Parodi F. , Pierini M. , Schiavi C. , Silvestrini L. , Sordini V. , Stocchi A. , Tarantino C. , Vagnoni V.
Published: October 2012

Abstract

We derive constraints on the parameters M
12, Γ12 and Φ12 that describe D meson mixing using all available data, allowing for CP violation. We also provide posterior distributions and predictions for observable parameters appearing in D physics.
The incidence of inherited porphyrias in Europe
Authors: Elder George , Harper Pauline , Badminton Michael , Sandberg Sverre , Deybach Jean‐Charles
Published: October 2012

Retrospective estimates of the prevalence of porphyrias have been reported but there has been no large scale prospective study of their incidence. The European Porphyria Network collected information prospectively over a 3 year period about the number of newly diagnosed symptomatic patients with an inherited porphyria (335 patients from 11 countries). Prevalence was calculated from the incidence and mean disease duration. The incidence of hepato‐cellular carcinoma (HCC) in acute hepatic porphyria and the prevalence of patients with recurrent acute attacks of porphyria were also investigated. The incidence of symptomatic acute intermittent porphyria (AIP) was similar in all countries (0.13 per million per year; 95 % CI: 0.10 – 0.14) except Sweden (0.51; 95 % CI: 0.28–0.86). The incidence ratio for symptomatic AIP: variegate porphyria: hereditary coproporphyria was 1.00:0.62: 0.15. The prevalence of AIP (5.4 per million; 95 % CI: 4.5–6.3) was about half that previously reported. The prevalence of erythropoietic protoporphyria (EPP) was less uniform between countries and, in some countries, exceeded previous estimates. Fourteen new cases of HCC (11 from Sweden) were reported in patients with acute porphyria. Sixty seven patients (3 VP; 64 AIP: 53 females, 11 males) with recurrent attacks of acute porphyria were identified. The estimated percentage of patients with AIP that will develop recurrent acute attacks was 3–5 %. In conclusion, the prevalence of symptomatic acute porphyria may be decreasing, possibly due to improved management, whereas the prevalence of EPP may be increasing due to improved diagnosis and its greater recognition as a cause of photosensitivity.
A set of novel modifications to improve algorithms from the A* family applied in mobile robotics
Authors: do Nascimento Tiago Pereira , Costa Pedro , Costa Paulo G. , Moreira António Paulo , Conceição André Gustavo Scolari
Published: October 2012

This paper presents a set of novel modifications that can be applied to any grid-based path planning algorithm from the A* family used in mobile robotics. Five modifications are presented regarding the way the robot sees an obstacle and its target to plan the robot’s path. The modifications make it possible for the robot to get to the target faster than traditional algorithms, as well as to avoid obstacles that move as fast as (or even faster than) the robot. Some simulations were made using a crowded and highly dynamic environment with twelve randomly moving obstacles. In these first simulations, a middle sized 5DPO robot was used. Also, real experiments were made with a small-sized version of a 5DPO robot to validate the algorithm’s effectiveness. In all simulations and real robot experiments the objects are considered to be moving at a constant speed. Finally, we present an overall discussion and conclusion of this paper.
Radiological Outcome of Patients with Splay Foot following First and Fifth Metatarsal Osteotomies Performed Simultaneously on the Same Foot
Authors: Hadi Mohammed , Walker Carolina , Fahad Attar , Sheriff Raheel , Gulam Attar
Published: October 2012

Introduction

There have been many operations documented for the treatment of hallux valgus and fifth metatarsal bunionette deformities in patients with splay foot carried out separately, with variable success rates. Our aim was to assess the radiological outcome following combined chevron osteotomy of the first and reverse chevron osteotomy of the fifth metatarsal in symptomatic patients with splay foot. To our knowledge, this procedure has not been described in the literature.

Methods

Nine symptomatic patients (12 feet) were included in the study. The preoperative and postoperative angles were assessed on weight-bearing radiographs for statistical significance using non-parametric paired t tests.

Results

The postoperative hallux valgus angles, intermetatarsal angles, first and fifth metatarsal head widths, and maximum distance between the first and fifth metatarsal heads decreased significantly (p < 0.05).

Conclusion

The results suggest a very good radiological outcome in symptomatic patients following simultaneous first and fifth metatarsal osteotomies. All the angles measured postoperatively, except the distal metatarsal articular angle, showed a statistically significant reduction.
Interprofessionalität als Schlüssel zum Erfolg
Authors: Ewers Michael
Published: October 2012

Einleitung

Gesundheitsprofessionen, die in interprofessionellen Teams gleichberechtigt komplementäre und ineinandergreifende Leistungen erbringen, gelten international als Schlüssel zum Erfolg einer patienten- und ergebnisorientierten Gesundheitsversorgung. In Deutschland behindern jedoch noch immer politische Forderungen nach Subordination unter die Medizin, hierarchische Muster der Zusammenarbeit und fehlende Initiativen für eine interprofessionelle Ausbildung die Erreichung dieses Ziels.
Fördermittel – der Weg von den Steuereinnahmen ins Förderprojekt
Authors: Kaffler Thomas
Published: October 2012

Einleitung

Der folgende Artikel gibt einen Überblick zum Haushaltsaufstellungsverfahren, einen Ausblick auf das im Jahr 2013 zu erwartende Budget für Gesundheitsthemen/Lebenswissenschaftliche Grundlagenforschung und einen Einblick in den Ablauf der Projektförderung des Bundesministeriums für Bildung und Forschung (BMBF).