bluuebunny/crossref_metadata_2025 huggingface dataset:
Fabrication and comparison of MoS2 and WSe2 field-effect transistor biosensors
Authors: Nam Hongsuk , Oh Bo-Ram , Chen Mikai , Wi Sungjin , Li Da , Kurabayashi Katsuo , Liang Xiaogan
Published: September 2015

The authors present a study on the evolution behaviors of the transfer characteristics of MoS2 and WSe2 field-effect transistor biosensors when they are subjected to tumor necrosis factor-alpha and streptavidin solutions with varying analyte concentrations. Both MoS2 and WSe2 sensors exhibit very low detection limits (∼60 fM for tumor necrosis factor-alpha detection; ∼70 fM for streptavidin detection). However, WSe2 sensors exhibit the higher linear-regime sensitivities in comparison with MoS2 sensors. In particular, WSe2 sensors exhibit high linear-regime sensitivities up to ∼1.54%/fM for detecting streptavidin at a concentration of ∼70 fM. Such relatively higher sensitivities obtained from WSe2 sensors are attributed to their intrinsic ambipolar transfer characteristics, which make their ON-state carrier concentrations significantly lower than those of MoS2 sensors, and therefore, the target-molecule-induced doping effect results in more prominent channel conductance modulation in WSe2 transistor sensors than in MoS2 sensors. Furthermore, this work strongly implies that the target-molecule-induced surface scattering also plays an important role in determining the response behaviors of the sensors made from atomically layered materials. Especially, the competition between target-molecule-induced p-doping and surface-scattering effects is responsible for the sensor behavior variation observed in the p-type conduction branch of WSe2 sensors. This work advances the critical device physics highly relevant with the fabrication and implementation of reliable nanoelectronic biosensors based on emerging atomically layered semiconductors.
Complete Genome Sequence Analysis of a Vaccine Strain of Foot-and-Mouth Disease Virus Serotype O from Pakistan
Authors: Shabbir Muhammad Zubair , Munir Muhammad
Published: September 2015

Sequencing and subsequent analysis of a vaccine strain of foot-and-mouth disease virus serotype O is reported here. Genomic heterogeneity in the protective epitopes (VP1 protein) of the reported strain, compared to characterized strains and available sequences from Pakistan, warrants further studies to determine vaccine-induced immunity and disease protection.
Draft Genome Sequence of an Alphaproteobacterium Associated with the Mediterranean Sponge
Oscarella lobularis
Authors: Jourda Cyril , Santini Sébastien , Rocher Caroline , Le Bivic André , Claverie Jean-Michel
Published: September 2015

While sequencing DNA purified from the homoscleromorph sponge
Oscarella lobularis
, we detected a large number of reads with strong similarity to available alphaproteobacteria gene sequences of family
Rhodobacteraceae
. Here, we present the genome sequence of this putative sponge symbiont that we propose to designate as “
Candidatus
Rhodobacter lobularis.”
Draft Genome Sequence of a Clinical Isolate of Serratia marcescens, Strain AH0650_Sm1
Authors: Wan Yu , Gorrie Claire L. , Jenney Adam , Mirceta Mirjana , Holt Kathryn E.
Published: September 2015

Serratia marcescens
strain AH0650_Sm1 is a clinical multidrug-resistant isolate from Australia. Here, we report its annotated draft genome comprising 20 contigs. We identified chromosomal antimicrobial resistance genes including a
tet
(41) variant, an
aac(6′)-Ic
variant,
ampC
, a metallo-beta-lactamase, and several putative multidrug efflux pumps, as well as a novel prophage.
Moxibustion Relieves Visceral Hyperalgesia via Inhibition of Transient Receptor Potential Vanilloid 1 (Trpv1) and Heat Shock Protein (Hsp) 70 Expression in Rat Bone Marrow Cells
Authors: Zou Weiying , Lin Hua , Liu Wenwen , Yang Bei , Wu Lei , Duan Limin , Ling Ping , Zhu Lingyan , Dai Qun , Zhao Lintong , Zou Ting , Zhang Dalei
Published: September 2015

Objective

To investigate the effects of moxibustion on visceral hyperalgesia (VH) and bone marrow cell transient receptor potential vanilloid type 1 (TRPV1) and heat shock protein (HSP) 70 expression in a rat model of VH.

Methods

Mechanical colorectal distension was performed to induce VH in neonatal Sprague-Dawley rats. Eight-week-old VH rats were treated with moxibustion at acupuncture point BL25 or an ipsilateral non-acupuncture point. Abdominal withdrawal reflex (AWR) scoring and pain threshold pressure assessment were performed before and after moxibustion treatment for 7 consecutive days. The expression of TRPV1 and HSP70 in bone marrow cells was quantified by real-time quantitative PCR.

Results

The expression of TRPV1 and HSP70 in bone marrow cells was increased in rats with VH. Moxibustion at BL25 significantly decreased AWR scores and increased pain threshold pressure in rats with VH. Furthermore, moxibustion at BL25 significantly inhibited the VH-induced increase in the expression of TRPV1 and HSP70 in bone marrow cells.

Conclusions

The up-regulation of TRPV1 and HSP70 expression in bone marrow cells may be involved in visceral pain development and the analgesic effect of moxibustion on VH may be mediated through down-regulation of TRPV1 and HSP70 expression in bone marrow cells.
Cardiac MRI-confirmed mesalamine-induced myocarditis
Authors: Baker William L , Saulsberry Whitney J , Elliott Kaitlyn , Parker Matthew W
Published: September 2015

A 38-year-old Caucasian man with a medical history significant for inflammatory bowel disease (IBD) and mesalamine use presented to the emergency department with stabbing, pleuritic, substernal chest pain over the previous 2 days. Findings of leucocytosis, elevated cardiac enzymes and inflammatory markers, T-wave or ST-segment abnormalities and left ventricular systolic dysfunction suggested mesalamine-induced myocarditis. However, a cardiac MRI confirmed the diagnosis. Signs and symptoms improved within days of withdrawal of mesalamine, and initiation of corticosteroids and follow-up studies within the next year were unremarkable. Importantly, the diagnosis of mesalamine-induced myocarditis confirmed via cardiac MRI is a step rarely performed in published cases.
A case of bilateral sensorineural hearing loss from Langerhans cell histiocytosis
Authors: Henderson Arthur Harry , Khan Akbar Ali , Good Catriona , Baer Simon T
Published: September 2015

Langerhans cell histiocytosis is a rare disorder, with resultant bilateral sensorineural hearing loss unreported in adults. A 42-year-old man presented with 4 months of right-sided tinnitus and hearing loss treated initially as otitis media with effusion. He re-presented 5 months later with progressive bilateral hearing loss—sensorineural (>100 dB) on pure tone audiogram. CT showed bilateral petrous temporal bone and calvarial lesions. Biopsy confirmed diagnosis of Langerhans cell histiocytosis and chemotherapy was started. Though uncommon, Langerhans cell histiocytosis should be considered among the differentials of persistent otological symptoms, as its progressive nature can cause bilateral irreversible sensorineural hearing loss.
Disabling chronic conditions in childhood and socioeconomic disadvantage: a systematic review and meta-analyses of observational studies
Authors: Spencer Nicholas J , Blackburn Clare M , Read Janet M
Published: September 2015

Objective

To determine the association of socioeconomic disadvantage with the prevalence of childhood disabling chronic conditions in high-income countries.

Study design

Systematic review and meta-analyses.

Data sources

6 electronic databases, relevant websites, reference lists and experts in the field.

Study selection

160 observational studies conducted in high-income countries with data on socioeconomic status and disabling chronic conditions in childhood, published between 1 January 1991 and 31 December 2013.

Data extraction and synthesis

Abstracts were reviewed, full papers obtained, and papers identified for inclusion by 2 independent reviewers. Inclusion decisions were checked by a third reviewer. Where reported, ORs were extracted for low versus high socioeconomic status. For studies reporting raw data but not ORs, ORs were calculated. Narrative analysis was undertaken for studies without data suitable for meta-analysis.

Results

126 studies had data suitable for meta-analysis. ORs for risk estimates were: all-cause disabling chronic conditions 1.72 (95% CI 1.48 to 2.01); psychological disorders 1.88 (95% CI 1.68 to 2.10); intellectual disability 2.41 (95% CI 2.03 to 2.86); activity-limiting asthma 2.20 (95% CI 1.87 to 2.85); cerebral palsy 1.42 (95% CI 1.26 to 1.61); congenital abnormalities 1.41 (95% CI 1.24 to 1.61); epilepsy 1.38 (95% CI 1.20 to 1.59); sensory impairment 1.70 (95% CI 1.39 to 2.07). Heterogeneity was high across most estimates (I2>75%). Of the 34 studies without data suitable for meta-analysis, 26 reported results consistent with increased risk associated with low socioeconomic status.

Conclusions

The findings indicate that, in high-income countries, childhood disabling chronic conditions are associated with social disadvantage. Although evidence of an association is consistent across different countries, the review provides limited evidence to explain the association; future research, using longitudinal data, will be required to distinguish low socioeconomic status as the cause or consequence of childhood disabling chronic conditions and the aetiological pathways and mechanisms.
Improving paediatric prescribing practice in a district general hospital through implementation of a quality improvement programme
Authors: Donnelly Peter , Lawson Sara , Watterson Claire
Published: September 2015

Prescribing errors are a well recognised cause of adverse incidents and have a direct effect on patients.[1] This impacts on the doctor-family relationship and results in breakdown of trust and communication.[2] This quality improvement project was carried out in the paediatric ward of a district general hospital in Northern Ireland. A retrospective analysis of paediatric prescribing errors between January and December 2013 identified two errors that were felt to be secondary to under-reporting. A baseline audit was subsequently performed that highlighted 32 errors across 12 drug charts.

A driver diagram identified three components contributing to prescribing errors and relevant tests of change were developed. The three primary drivers included: education and communication, practical prescribing changes, and medicine reconciliation. Seven interventions were implemented sequentially over a six month period and their effectiveness assessed by a prospective drug chart audit. Ten drug charts were selected at random by the staff nurse allocated to medications on the day of audit. The charts were audited using a predesigned proforma and the total number of errors counted. These were subcategorised and results displayed in graphical format after each intervention.

Seven audit cycles were completed in total after each intervention was put into practice. The number of errors (including percentage change following each intervention) is as follows: intervention 1: 32 (+19%); Intervention 2: 31 (+15%); Intervention 3: 17 (-37%); Intervention 4: 12 (-56%); Intervention 5: 15 (-44%); Intervention 6: 7 (-74%); Intervention 7: 10 (-63%). In conclusion, permanent and successful measures are needed to reduce prescribing errors in order to minimise the impact of staff changeover and knowledge deficits.
THE IMPACT OF POPULATION AGEING ON ECONOMIC GROWTH: A BIBLIOMETRIC SURVEY
Authors: NAGARAJAN RENUGA , TEIXEIRA AURORA A. C. , SILVA SANDRA
Published: September 2015

Population ageing and its influence on the economic growth has long been the focus of major concern. Using bibliometric techniques we found that: (1) although ageing has increasingly attracted more researchers within economics literature, the relative weight of ageing and economic growth related papers does not evidence a clear positive trend; (2) recent studies reveal the willingness of researchers to evaluate less immediate mechanisms relating ageing and economic growth; (3) the increase in the use of empirical methods reflects a trend to test economic phenomena with real-world data against the theory; (4) very few studies focus on developing and less developed countries.
EXCHANGE RATE AND US MACROECONOMY: EVIDENCE FROM THE FACTOR-AUGMENTED VECTOR AUTOREGRESSIVE MODEL
Authors: AN LIAN , REN XIAOMEI , LI HUIMIN , XU JING
Published: September 2015

This paper aims to examine the macroeffects of exchange rate movements on a wide array of real economic variables in the US in a unifying model. By employing the non-linear factor-augmented vector autoregressive (FAVAR) model with simulation methods, we could trace the effects of exchange rate appreciation and depreciation on a wide array of macroeconomic variables through the impulse response function (IRF). The main findings are: (1) In response to dollar depreciation, import price index (IMP), producer price index (PPI) and CPI increase significantly. The pass-through ratio declines along the distribution chain. (2) Merchandise trade balance, current account balance and output improve facing dollar depreciation. (3) Savings decreases in response to dollar depreciation. (4) Employment and average hourly earnings increase in times of exchange rate depreciation and vice versa. The effects on macroeconomy from appreciation and depreciation seem symmetric. Many other interesting findings are also documented.
ANALYSIS OF GENDER WAGE DIFFERENTIAL IN CHINA’S URBAN LABOR MARKET
Authors: HESHMATI ALMAS , SU BIWEI
Published: September 2015

This paper estimates the gender wage gap and its composition in China’s urban labor market. The traditional Blinder–Oaxaca (1973) decomposition method with different weighing systems is employed. To correct for potential selection bias caused by women’s labor force participation, we employ the Heckman’s two-step procedure to estimate the female wage function. A large proportion of the gender wage gap is unexplained by differences of productive characteristics of individuals. Even though women have higher level of education attainments on average, they receive lower wages than men. Both facts suggest a potential discrimination against women in China.
TRANSFER PAYMENTS AND UPPER SECONDARY SCHOOL OUTCOMES: THE CASE OF LOW-INCOME FEMALE STUDENTS IN THAILAND
Authors: VECHBANYONGRATANA JESSICA , PAWEENAWAT SASIWIMON WARUNSIRI
Published: September 2015

This study assesses the impact of cash transfers to low-income female Thai students on improving upper secondary school outcomes, as measured by grade point average (GPA) and transition to tertiary education. Utilizing official records from a charity organization providing substantial cash transfers to secondary students and student records from participating schools, we find the transfers have no effect on improving recipients’ GPAs compared to non-recipients. However, the scholarship recipients are 22% more likely to transition to university education than non-recipients and the presence of scholarship recipients in the classroom increases the likelihood of female non-recipients to attend university.
BALANCING ACT: ADJUSTMENT OF CHINA'S ECONOMY TO SECURE SUSTAINABLE GROWTH
Authors: YUTIAN SHI , HICKS JOHN , BASU P. K. , SHARMA KISHOR , BANDARA YAPA , MURPHY TOM
Published: September 2015

This paper uses income accounting techniques to assess, counterfactually, the implied impact over the last 10 years of a hypothetical government policy to constrain investment growth in order to raise the share of consumption in GDP and to bring about a balance on current account. We find that both target variables are very sensitive to changes in investment and that a policy of careful reform is called for. In the light of this finding, we review Chinese government policy pronouncements and activity with a view to assessing their appropriateness.
Studies on the g factors of tetragonal Cu2+ sites in NdBa2Cu3Ox and Nd0.05Y0.95Ba2Cu3O6
Authors: He Jia-Jun , Wu Shao-Yi , Zhang Zhi-Hong , Dong Hui-Ning
Published: September 2015

The anisotropic [Formula: see text] factors are theoretically studied for the [Formula: see text] sites in [Formula: see text] and [Formula: see text] from the perturbation formulas of the [Formula: see text] factors for a [Formula: see text] ion in tetragonally elongated octahedra. The local low symmetrical (tetragonal) distortions of the five-fold coordinated [Formula: see text] sites are quantitatively correlated to the electron paramagnetic resonance (EPR) analysis in terms of the tetragonal field parameters based on the superposition model, and the ligand contributions are included in view of obvious covalency. The possibility of the above EPR signals arising from [Formula: see text] may be excluded for both systems.
Effect of oxygen on the magnetic property of Bis(8-hydroxyquinoline)copper (CuQ2): An experimental and theoretical study
Authors: Jiang Feng , Yuan Huimin , Xie Wanfeng , Pang Zhiyong , Han Shenghao
Published: September 2015

The magnetic properties of bis(8-hydroxyquinoline)copper ([Formula: see text]) were investigated by experiments and first-principles density functional theory (DFT) calculations. The as-prepared [Formula: see text] film shows paramagnetic behavior. After annealing in air, room temperature ferromagnetic (FM) properties were found in [Formula: see text] film. The Fourier transform infrared spectroscopy (FTIR) analysis indicates a new vibrational mode related to out of plane O–H bend in the annealed film. DFT calculations show that the energy difference between the FM and the antiferromagnetic (AFM) states is greatly increased after O doping, which may be responsible for the room temperature ferromagnetism in the annealed [Formula: see text] film.
Controlling superconductivity in thin film with an external array of magnetic nanostructures
Authors: Bang Wonbae , Teizer W. , Rathnayaka K. K. D. , Lyuksyutov I. F. , Naugle D. G.
Published: September 2015

We have fabricated a new type of magnet-superconductor hybrid (MSH): an ordered array of magnetic nanorods atop a superconducting film electrically insulated from the array. Transport properties of this MSH, [Formula: see text] and [Formula: see text] are reported. We compare these results with those for a superconducting film atop an alumina template with an array of magnetic nanowires.
An Efficient Two-Stage Sparse Representation Method
Authors: Peng Chengyu , Cheng Hong , Ko Manchor
Published: September 2015

There are a large number of methods for solving under-determined linear inverse problems. For large-scale optimization problem, many of them have very high time complexity. We propose a new method called two-stage sparse representation (TSSR) to tackle it. We decompose the representing space of signals into two parts”, the measurement dictionary and the sparsifying basis. The dictionary is designed to obey or nearly obey the sub-Gaussian distribution. The signals are then encoded on the dictionary to obtain the training and testing coefficients individually in the first stage. Then, we design the basis based on the training coefficients to approach an identity matrix, and we apply sparse coding to the testing coefficients over the basis in the second stage. We verify that the projection of testing coefficients onto the basis is a good approximation of the original signals onto the representing space. Since the projection is conducted on a much sparser space, the runtime is greatly reduced. For concrete realization, we provide an instance for the proposed TSSR. Experiments on four biometric databases show that TSSR is effective compared to several classical methods for solving linear inverse problem.
Bifurcation and Firing Patterns of the Pancreatic β-Cell
Authors: Wang Jing , Liu Shenquan , Liu Xuanliang , Zeng Yanjun
Published: September 2015

Using a model of individual isolated pancreatic β-cells, we investigated bifurcation diagrams of interspike intervals (ISIs) and largest Lyapunov exponents (LLE), which clearly demonstrated a wide range of transitions between different firing patterns. The numerical simulation results revealed the effect of different time constants and ion channels on the neuronal discharge rhythm. Furthermore, an individual cell exhibited tonic spiking, square-wave bursting, and tapered bursting. Additionally, several bifurcation phenomena can be observed in this paper, such as period-doubling, period-adding, inverse period-doubling and inverse period-adding scenarios. In addition, we researched the mechanisms underlying two kinds of bursting (tapered and square-wave bursting) by use of fast-slow dynamics analysis. Finally, we analyzed the codimension-two bifurcation of the fast subsystem and studied cusp bifurcation, generalized Hopf (or Bautin) bifurcation and Bogdanov–Takens bifurcation.
Stability and Perturbations of Homoclinic Loops in a Class of Piecewise Smooth Systems
Authors: Chen Shuang , Du Zhengdong
Published: September 2015

Like for smooth systems, a typical method to produce multiple limit cycles for a given piecewise smooth planar system is via homoclinic bifurcation. Previous works only focused on limit cycles that bifurcate from homoclinic orbits of piecewise-linear systems. In this paper, we consider for the first time the same problem for a class of general nonlinear piecewise smooth systems. By introducing the Dulac map in a small neighborhood of the hyperbolic saddle, we obtain the approximation of the Poincaré map for the nonsmooth homoclinic orbit. Then, we give conditions for the stability of the homoclinic orbit and conditions under which one or two limit cycles bifurcate from it. As an example, we construct a nonlinear piecewise smooth system with two limit cycles that bifurcate from a homoclinic orbit.
New Phenomena in the Spatial Isosceles Three-Body Problem
Authors: Yan Duokui , Ouyang Tiancheng
Published: September 2015

In the three-body problem, it is known that there exists a special set of periodic orbits: spatial isosceles periodic orbits. In each period, one body moves up and down along a straight line, and the other two bodies rotate around this line. In this work, we revisit this set of orbits by applying variational method. Two unexpected phenomena are discovered. First, this set is not always spatial. It actually bifurcates from the circular Euler (central configuration) orbit to the Broucke (collision) orbit. Second, one of the orbits in this set encounters an oscillating behavior. By running its initial condition, the orbit stays periodic for only a few periods before it becomes irregular. However, it moves close to another periodic shape in a while. Shortly it falls apart again and starts running close to a third periodic shape after a moment. This oscillation continues as t increases. Actually, up to t = 1.2 × 105, the orbit is bounded and keeps oscillating between periodic shapes and irregular motions.
Stability and Bifurcation Analysis of a Three-Species Food Chain Model with Delay
Authors: Pal Nikhil , Samanta Sudip , Biswas Santanu , Alquran Marwan , Al-Khaled Kamel , Chattopadhyay Joydev
Published: September 2015

In the present paper, we study the effect of gestation delay on a tri-trophic food chain model with Holling type-II functional response. The essential mathematical features of the proposed model are analyzed with the help of equilibrium analysis, stability analysis, and bifurcation theory. Considering time-delay as the bifurcation parameter, the Hopf-bifurcation analysis is carried out around the coexisting equilibrium. The direction of Hopf-bifurcation and the stability of the bifurcating periodic solutions are determined by applying the normal form theory and center manifold theorem. We observe that if the magnitude of the delay is increased, the system loses stability and shows limit cycle oscillations through Hopf-bifurcation. The system also shows the chaotic dynamics via period-doubling bifurcation for further enhancement of time-delay. Our analytical findings are illustrated through numerical simulations.
Some Polynomial Chaotic Maps Without Equilibria and an Application to Image Encryption with Avalanche Effects
Authors: Min Lequan , Yang Xiuping , Chen Guanrong , Wang Danling
Published: September 2015

This study uses seven four-dimensional four-variable polynomial chaotic maps without equilibria in combination with generalized chaos synchronization (GCS) theorem to construct eight-dimensional bidirectional discrete generalized chaos synchronization (8DBDGCS) systems without equilibria. By combining the 8DBDGCS system with the GCS theorem, a 12-dimensional GCS system is designed. Numerical simulation verifies the chaotic dynamics of the 12-dimensional GCS system, which is used to design a 216-word chaotic pseudorandom number generator (CPRNG). The SP-8002 test suite is used to test the randomness of four 100-key streams consisting of 1 000 000 bits generated respectively by the CPRNG, a six-dimensional GCS-based CPRNG, the RC4 algorithm and the ZUC algorithm. The results show that the randomness performances of the two CPRNGs are promising, suggesting that there are no significant correlations between the key stream and the perturbed key streams generated via the 216-word CPRNG. In addition, theoretically the key space of the CPRNG is larger than 21195. The CPRNG is used with an avalanche-encryption scheme to encrypt an RGB balloon image, demonstrating that the CPRNG is able to generate the avalanche effects which are similar to those generated via ideal 216-word CPRNGs.
CoNCoS: Copy number estimation in cancer with controlled support
Authors: Abdallah Ali T. , Fischer Matthias , Nürnberg Peter , Nothnagel Michael , Frommolt Peter
Published: September 2015

Somatic copy number (CN) alterations are major drivers of tumorigenesis and growth. Although next-generation sequencing (NGS) technologies enable a deep genomic analysis of cancers, the analysis of the data remains subject to biases and multiple sources of error, including varying local read coverage. The currently existing algorithms for NGS-based detection of CN abberations do not incorporate information on the local coverage quality. We have developed a new algorithm, copy number estimation with controlled support (CoNCoS) that increases the accuracy of CN estimation in paired tumor/normal exome sequencing data sets by assessing and optimizing the support for a site-specific CN estimate. We show by simulations and in a benchmarking study against single nucleotide polymorphism (SNP) microarray data that our approach outperforms the commonly used methods CNAnorm and VarScan2. Our algorithm is suitable to increase the accuracy of somatic CN analysis by a support-optimized estimation approach.
A Technique with a Correction Term for Unsteady State Heat Transfer Problem with Moving Boundary
Authors: Niu R. P. , Liu G. R. , Li M.
Published: September 2015

The paper proposes a general formulation for simulating unsteady state heat transfer problem with moving boundaries. The method is equipped with a correction term based on the finite element method. In dealing with the unsteady behavior, forward time marching is performed using the finite difference method. We introduce a correction term to effectively deal with the moving boundary effects, which directly uses the nodal temperature at the previous step in the time marching process. A mathematical study has been conducted to examine the theoretical basis. Finally, intensive numerical experiments are conducted to demonstrate effectiveness and stability of the proposed procedure.
Protein Fibrillar Nanopolymers: Molecular-Level Insights into Their Structural, Physical and Mechanical Properties
Authors: Trusova Valeriya M.
Published: September 2015

Amyloid fibrils represent a generic class of mechanically strong and stable biomaterials with extremely advantageous properties. Although amyloids were initially associated only with severe neurological disorders, the role of these structures nowadays is shifting from health debilitating to highly beneficial both in biomedical and technological aspects. Intensive involvement of fibrillar assemblies into the wide range of pathogenic and functional processes strongly necessitate the molecular level characterization of the structural, physical and elastic features of protein nanofibrils. In the present contribution, we made an attempt to highlight the up-to-date progress in the understanding of amyloid properties from the polymer physics standpoint. The fundamental insights into protein fibril behavior are essential not only for development of therapeutic strategies to combat the protein misfolding disorders but also for rational and precise design of novel biodegradable protein-based nanopolymers.
Analysis of opto-thermal interaction of porcine stomach tissue with 808-nm laser for endoscopic submucosal dissection
Authors: Kim Seongjun , Hossain M. Tamim , Lee Don Haeng , Kim Jung Kyung
Published: September 2015

In endoscopic submucosal dissection (ESD), the narrow gastrointestinal space can cause difficulty in surgical interventions. Tissue ablation apparatuses with high-power CO 2 lasers or Nd :YAG lasers have been developed to facilitate endoscopic surgical procedures. We studied the interaction of 808-nm laser light with a porcine stomach tissue, with the aim of developing a therapeutic medical device that can remove lesions at the gastrointestinal wall by irradiating a near-infrared laser light incorporated in an endoscopic system. The perforation depths at the porcine fillet and the stomach tissues linearly increased in the range of 2–8 mm in proportion to the laser energy density of 63.7–382 kJ/cm2. Despite the distinct structural and compositional difference, the variation of the perforation depth between the stomach and the fillet was not found at 808-nm wavelength in our measurement. We further studied the laser–tissue interaction by changing the concentration of the methyl blue solution used conventionally as a submucosal fluidic cushion (SFC) in ESD procedures. The temperature of the mucosal layer increased more rapidly at higher concentration of the methyl blue solution, because of enhanced light absorption at the SFC layer. The insertion of the SFC would protect the muscle layer from thermal damage. We confirmed that more effective laser treatment should be enabled by tuning the opto-thermal properties of the SFC. This study can contribute to the optimization of the driving parameters for laser incision techniques as an alternative to conventional surgical interventions.
Dietary vitamin D3 deficiency alters intestinal mucosal defense and increases susceptibility toCitrobacter rodentium-induced colitis
Authors: Ryz Natasha R. , Lochner Arion , Bhullar Kirandeep , Ma Caixia , Huang Tina , Bhinder Ganive , Bosman Else , Wu Xiujuan , Innis Sheila M. , Jacobson Kevan , Vallance Bruce A.
Published: September 2015

Vitamin D deficiency affects more that 1 billion people worldwide. Although thought to increase risk of bacterial infections, the importance of vitamin D on host defense against intestinal bacterial pathogens is currently unclear since injection of the active form of vitamin D, 1,25(OH)2D3, increased susceptibility to the enteric bacterial pathogen Citrobacter rodentium by suppressing key immune/inflammatory factors. To further characterize the role of vitamin D during bacteria-induced colitis, we fed weanling mice either vitamin D3-deficient or vitamin D3-sufficient diets for 5 wk and then challenged them with C. rodentium. Vitamin D3-deficient mice lost significantly more body weight, carried higher C. rodentium burdens, and developed worsened histological damage. Vitamin D3-deficient mice also suffered greater bacterial translocation to extra-intestinal tissues, including mesenteric lymph nodes, spleen, and liver. Intestinal tissues of infected vitamin D3-deficient mice displayed increased inflammatory cell infiltrates as well as significantly higher gene transcript levels of inflammatory mediators TNF-α, IL-1β, IL-6, TGF-β, IL-17A, and IL-17F as well as the antimicrobial peptide REG3γ. Notably, these exaggerated inflammatory responses accelerated the loss of commensal microbes and were associated with an impaired ability to detoxify bacterial lipopolysaccharide. Overall, these studies show that dietary-induced vitamin D deficiency exacerbates intestinal inflammatory responses to infection, also impairing host defense.
Effects of striatal nitric oxide production on regional cerebral blood flow and seizure development in rats exposed to extreme hyperoxia
Authors: Gasier Heath G. , Demchenko Ivan T. , Allen Barry W. , Piantadosi Claude A.
Published: September 2015

The endogenous vasodilator and signaling molecule nitric oxide has been implicated in cerebral hyperemia, sympathoexcitation, and seizures induced by hyperbaric oxygen (HBO2) at or above 3 atmospheres absolute (ATA). It is unknown whether these events in the onset of central nervous system oxygen toxicity originate within specific brain structures and whether blood flow is diverted to the brain from peripheral organs with high basal flow, such as the kidney. To explore these questions, total and regional cerebral blood flow (CBF) were measured in brain structures of the central autonomic network in anesthetized rats in HBO2at 6 ATA. Electroencephalogram (EEG) recordings, cardiovascular hemodynamics, and renal blood flow (RBF) were also monitored. As expected, mean arterial blood pressure and total and regional CBF increased preceding EEG spikes while RBF was unaltered. Of the brain structures examined, the earliest rise in CBF occurred in the striatum, suggesting increased neuronal activation. Continuous unilateral or bilateral striatal infusion of the nitric oxide synthase inhibitor Nω-nitro-l-arginine methyl ester attenuated CBF responses in that structure, but global EEG discharges persisted and did not differ from controls. Our novel findings indicate that: 1) cerebral hyperemia in extreme HBO2in rats does not occur at the expense of renal perfusion, highlighting the remarkable autoregulatory capability of the kidney, and 2) in spite of a sentinel increase in striatal blood flow, additional brain structure(s) likely govern the pathogenesis of HBO2-induced seizures because EEG discharge latency was unchanged by local blockade of striatal nitric oxide production and concomitant hyperemia.
Regulation of energy expenditure by estradiol in premenopausal women
Authors: Melanson Edward L. , Gavin Kathleen M. , Shea Karen L. , Wolfe Pamela , Wierman Margaret E. , Schwartz Robert S. , Kohrt Wendy M.
Published: September 2015

Suppressing sex hormones in women for 1 wk reduces resting energy expenditure (REE). The effects of more chronic suppression on REE and other components of total energy expenditure (TEE), and whether the reduction in REE is specifically due to loss of estradiol (E2), are not known. We compared the effects of 5 mo of sex hormone suppression (gonadotropin releasing hormone agonist therapy, GnRHAG) with placebo (PL) or E2add-back therapy on REE and the components of TEE. Premenopausal women received GnRHAG(leuprolide acetate 3.75 mg/mo) and were randomized to receive transdermal therapy that was either E2(0.075 mg/d; n = 24; means ± SD, aged = 37 ± 8 yr, BMI = 27.3 ± 6.2 kg/m2) or placebo ( n = 21; aged = 34 ± 9 yr, BMI = 26.8 ± 6.2 kg/m2). REE was measured by using a metabolic cart, and TEE, sleep EE (SEE), exercise EE (ExEE, 2 × 30 min bench stepping), non-Ex EE (NExEE), and the thermic effect of feeding (TEF) were measured by using whole room indirect calorimetry. REE decreased in GnRHAG+PL [mean (95% CI), −54 (−98, −15) kcal/d], but not GnRHAG+E2[+6 (−33, +45) kcal/d] (difference in between-group changes, P < 0.05). TEE decreased in GnRHAG+PL [−128 (−214, −41) kcal/d] and GnRHAG+E2[−96 (−159, −32) kcal/d], with no significant difference in between-group changes ( P = 0.55). SEE decreased similarly in both GnRHAG+PL [−0.07 (−0.12, −0.03) kcal/min] and GnRHAG+E2[−0.07 (−0.12, −0.02) kcal/min]. ExEE decreased in GnRHAG+PL [−0.46 (−0.79, −0.13) kcal/min], but not GnRHAG+E2[−0.30 (−0.65, +0.06) kcal/min]. There were no changes in TEF or NExEE in either group. In summary, chronic pharmacologic suppression of sex hormones reduced REE and this was prevented by E2therapy.
Observation of cardiogenic flow oscillations in healthy subjects with hyperpolarized3He MRI
Authors: Collier Guilhem J. , Marshall Helen , Rao Madhwesha , Stewart Neil J. , Capener David , Wild Jim M.
Published: September 2015

Recently, dynamic MRI of hyperpolarized3He during inhalation revealed an alternation of the image intensity between left and right lungs with a cardiac origin (Sun Y, Butler JP, Ferrigno M, Albert MS, Loring SH. Respir Physiol Neurobiol 185: 468–471, 2013). This effect is investigated further using dynamic and phase-contrast flow MRI with inhaled3He during slow inhalations (flow rate ∼100 ml/s) to elucidate airflow dynamics in the main lobes in six healthy subjects. The ventilation MR signal and gas inflow in the left lower lobe (LLL) of the lungs were found to oscillate clearly at the cardiac frequency in all subjects, whereas the MR signals in the other parts of the lungs had a similar oscillatory behavior but were smaller in magnitude and in anti-phase to the signal in the left lower lung. The airflow in the main bronchi showed periodic oscillations at the frequency of the cardiac cycle. In four of the subjects, backflows were observed for a short period of time of the cardiac cycle, demonstrating a pendelluft effect at the carina bifurcation between the left and right lungs. Additional1H structural MR images of the lung volume and synchronized ECG recording revealed that maximum inspiratory flow rates in the LLL of the lungs occurred during systole when the corresponding left lung volume increased, whereas the opposite effect was observed during diastole, with gas flow redirected to the other parts of the lung. In conclusion, cardiogenic flow oscillations have a significant effect on regional gas flow and distribution within the lungs.
NF-κB: Regulation by Methylation
Authors: Lu Tao , Stark George R.
Published: September 2015

In normal cells exposed to stress, the central transcription factor NF-κB is activated only transiently, to modulate the activation of downstream immune responses. However, in most cancers, NF-κB is abnormally activated constitutively, contributing thus to oncogenesis and tumor progression. Therefore, downregulating NF-κB activity is an important goal of cancer treatment. In order to control NF-κB activity therapeutically, it is helpful to understand the molecular mechanisms that normally govern its activation and how dysregulated NF-κB activity may aid the development of disease. Recent evidence from our laboratories and others indicates that, in addition to various posttranslational modifications of NF-κB that have been observed previously, including phosphorylation, ubiquitination, and acetylation, NF-κB can be methylated reversibly on lysine or arginine residues by histone-modifying enzymes, including lysine and arginine methyl transferases and demethylases. Furthermore, these methylations are required to activate many downstream genes. Interestingly, amplifications and mutations of several such enzymes have been linked to cancer. We propose that some of these mutations may alter the methylation not only of histones but also of NF-κB, making them attractive therapeutic targets. Cancer Res; 75(18); 3692–5. ©2015 AACR.
Medical Therapy of Perianal Crohn's Disease
Authors: Klag Thomas , Goetz Martin , Stange Eduard F. , Wehkamp Jan
Published: September 2015

Background: Development of perianal fistulas are a common feature of Crohn's disease (CD). Consequences are severe impairment of quality of life as well as potentially life-threatening complications like abscess formation or bacterial sepsis. Therefore, appropriate treatment is an important task in the management of CD. Methods: This review describes the epidemiology, pathogenesis, diagnosis, and conservative medical treatment of perianal CD with regard to the available literature. In February 2015, a PubMed search was performed with the following terms (combined and separate): ‘Crohn's disease management', ‘Crohn's disease complications', ‘perianal Crohn's disease', ‘fistulizing Crohn's disease', ‘perianal fistulas', ‘fistula healing', ‘fistula closure'. From the search results, 36 articles were chosen as core elements of this review. Results: Pelvic magnetic resonance imaging and rectal endosonography are established diagnostic approaches to evaluate perianal fistulas in conjunction with endoscopy. Antibiotics, thiopurines, and calcineurin inhibitors are useful agents in the management of perianal CD. The availability of anti-TNF-alpha therapies has substantially changed the prospects and goals of medical treatment, and fistula healing seems to be possible in a substantial proportion of patients. Conclusion: Antibiotics and several immunosuppressive drugs have improved the treatment of fistulizing CD and should be combined with surgical measures.
Unnecessary Procedures and Surgery in Autoimmune Pancreatitis
Authors: Manser Christine N. , Gubler Christoph , Müllhaupt Beat , Bauerfeind Peter
Published: September 2015

Background/Aims: To identify the number and potential causes of unnecessary diagnostic procedures in a cohort of patients with autoimmune pancreatitis (AIP). Methods: All AIP cases at our centre between April 2006 and April 2013 were collected and followed up. Diagnosis was established by the International Consensus Diagnostic Criteria (ICDC). Demographic, clinical, radiological, serological data, the number of diagnostic procedures and the reason for referral were recorded. Possible risk factors for a delayed diagnosis of AIP were analysed. Results: A total of 29 patients (median age 60 years; 22 males and 7 females) were diagnosed with AIP using ICDC. Twenty-five patients were diagnosed with definite, 2 with possible type 1 AIP and 2 with type 2 AIP. In 29 patients, 50 ERCPs and 18 EUS were carried out; based on ICDC recommendations, a total of 20 ERCPs and 4 EUS were unnecessary diagnostic procedures. Eight patients (23.0%) were referred for unnecessary surgery. Jaundice was shown to be a significant risk factor for unnecessary endoscopic investigations (OR 11.00, 95% CI 1.14-106.43, p = 0.04). Conclusion: Diagnosis of AIP still remains a challenge. Patients with jaundice are at particular risk of being subjected to unnecessary endoscopic procedures. Use of ICDC would help avoid unnecessary examinations or even major surgeries at times.
Occult and Manifest Colorectal Carcinoma in Ulcerative Colitis: How Does It Influence Surgical Decision Making?
Authors: Hardt Julia , Kienle Peter
Published: September 2015

Background: The incidence of colorectal cancer (CRC) among patients with ulcerative colitis (UC) is increased compared to the general population. The diagnosis of CRC potentially influences surgical decision making in patients with UC. Methods: This review considers clinical studies, systematic reviews, and guidelines on the surgical therapy of CRC in UC. We searched the bibliographic databases The Cochrane Library and Medline (applying MeSH terms such as ‘Colitis, Ulcerative/surgery', ‘Colorectal Neoplasms', and ‘Proctocolectomy, Restorative') with no restriction on language, date, or country. Search results as well as references of relevant publications were independently screened by both authors of this review. Results: The surgical gold standard for proven CRC in UC is oncological proctocolectomy, if possible preferably as a restorative procedure with formation of an ileal pouch-anal anastomosis. Mucosectomy and hand-sewn anastomosis is the preferred option for fashioning the anastomosis in these patients, especially in case of dysplasia or cancer in the rectum, although the available data is not conclusive. In highly selected cases of patients with histologically confirmed sporadic CRC without dysplasia in multiple random biopsies and without relevant inflammation, a conventional limited oncological resection is adequate. If UC patients with rectal cancer require radiotherapy, it should be performed in a neoadjuvant setting because of the high risk of radiation-induced pouch failure. Conclusion: Although restorative proctocolectomy is clearly the gold standard therapy for patients with CRC in UC, surgical decision making has to take into account the various settings and patient factors.
Surgical Principles in the Treatment of Ulcerative Colitis
Authors: Kühn Florian , Klar Ernst
Published: September 2015

Background: The primary treatment of ulcerative colitis (UC) is conservative; surgical intervention is carried out in the case of therapy-refractory situation, imminent or malignant transformation, or complications. Surgery for UC should be indicated by interdisciplinary means. Despite the development of drug therapy - in particular the introduction of biologics -, a surgical intervention becomes necessary in a relevant proportion of patients with UC throughout lifetime. Methods: A selective literature search was conducted, taking into account the current studies, reviews, meta-analyses, and guidelines. PubMed served as a database. The present work gives an overview of the surgical options, outcome as well as peri- and postoperative management for patients with UC. Results: Approximately 20% of patients with UC will require surgery during the course of their disease. The rate of colectomy after a disease duration of 10 years is at approximately 16%. Unlike Crohn's disease, UC is principally surgically curable since it is naturally limited to the colon and rectum. Restorative proctocolectomy with an ileal pouch-anal anastomosis represents the surgical treatment of choice. Large studies show a postoperative complication rate of around 30% and a low mortality of 0.1% for this procedure. Chronic pouchitis is one of the main factors limiting the surgical success of curing UC. Despite a high postoperative complication rate, there is a long-term pouch success rate of >90% after 10 and 20 years of follow-up. Conclusion: A close cooperation between the various disciplines in the pre- and postoperative setting is essential for an optimal outcome of patients with UC. Despite a 30% rate of early postoperative complications, normal quality of life can ultimately be reached in more than 90% of patients in experienced centers.
Vitamin D Status and Its Determinants in Healthy Slovenian Pregnant Women
Authors: Soltirovska Salamon Aneta , Benedik Evgen , Bratanič Borut , Velkavrh Manca , Rogelj Irena , Fidler Mis Nataša , Bogovič Matijašić Bojana , Paro-Panjan Darja
Published: September 2015

Background/Aims: Vitamin D deficiency is a common underdiagnosed condition. The aim of this was to analyze the status of vitamin D and its determinants in healthy Slovenian pregnant women. Methods: A total of 132 volunteer pregnant women completed a questionnaire including baseline demographics, food frequency, physical activities; anthropometrical measurements, body mass index and levels of 25-(OH)D in serum were performed during the third trimester, and dietary intakes were assessed during the 27-28th week of gestation. Results: Vitamin D deficiency was present in 14% while insufficiency was present in 41% of women. The risk for inadequacy was higher in women older than 30 years (p = 0.01), in those with less frequent outdoor physical activity (p = 0.01) and in pregnancies during the low sun exposure season (p = 0.04). Insufficiency was not significantly more frequent in less educated women, unemployed and in those living in urban area. The median value of vitamin D from habitual dietary intake was 1.5 µg/day (range 0.1-13.4) and did not influence 25-hydroxyvitamin D level (p = 0.91). Conclusions: The prevalence of vitamin D inadequacy was 55% and was dependent on age, season and outdoor physical activities. The results suggest a discrepancy between vitamin D intake through habitual diet and the reference needs.