bluuebunny/crossref_metadata_2025 huggingface dataset:
Activation of the
Listeria monocytogenes
Virulence Program by a Reducing Environment
Authors: Portman Jonathan L. , Dubensky Samuel B. , Peterson Bret N. , Whiteley Aaron T. , Portnoy Daniel A.
Published: October 2017

Upon entry into the host cell cytosol, the facultative intracellular pathogen
Listeria monocytogenes
coordinates the expression of numerous essential virulence factors by allosteric binding of glutathione (GSH) to the Crp-Fnr family transcriptional regulator PrfA. Here, we report that robust virulence gene expression can be recapitulated by growing bacteria in a synthetic medium containing GSH or other chemical reducing agents. Bacteria grown under these conditions were 45-fold more virulent in an acute murine infection model and conferred greater immunity to a subsequent lethal challenge than bacteria grown in conventional media. During cultivation
in vitro
, PrfA activation was completely dependent on the intracellular levels of GSH, as a glutathione synthase mutant (Δ
gshF
) was activated by exogenous GSH but not reducing agents. PrfA activation was repressed in a synthetic medium supplemented with oligopeptides, but the repression was relieved by stimulation of the stringent response. These data suggest that cytosolic
L. monocytogenes
interprets a combination of metabolic and redox cues as a signal to initiate robust virulence gene expression
in vivo
.

IMPORTANCE
Intracellular pathogens are responsible for much of the worldwide morbidity and mortality from infectious diseases. These pathogens have evolved various strategies to proliferate within individual cells of the host and avoid the host immune response. Through cellular invasion or the use of specialized secretion machinery, all intracellular pathogens must access the host cell cytosol to establish their replicative niches. Determining how these pathogens sense and respond to the intracellular compartment to establish a successful infection is critical to our basic understanding of the pathogenesis of each organism and for the rational design of therapeutic interventions.
Listeria monocytogenes
is a model intracellular pathogen with robust
in vitro
and
in vivo
infection models. Studies of the host-sensing and downstream signaling mechanisms evolved by
L. monocytogenes
often describe themes of pathogenesis that are broadly applicable to less tractable pathogens. Here, we describe how bacteria use external redox states as a cue to activate virulence.
Tenderness and sensory attributes of 11 muscles from carcasses within the Canadian cull cow grades
Authors: Roberts Jordan C. , Rodas-González Argenis , Juárez Manuel , López-Campos Óscar , Larsen Ivy L. , Aalhus Jennifer L.
Published: October 2017

The eating quality and shear force of meat from mature beef carcasses graded within the Canadian grading system were compared with youthful carcasses. Eleven muscles were obtained from mature-graded carcasses with >50% ossification (D1, D2, D3, and D4; n = 84) and youthful carcasses with <50% ossification [over 30 mo (OTM); n = 18, and under 30 mo (UTM) of age; n = 18, based on dentition]; muscles were aged 14 d prior to sensory and shear force analysis. Many muscles from mature-graded carcasses were juicier than UTM, however, most were less tender (P < 0.05). Psoas major was tender, particularly in D1 and OTM carcasses where tenderness measures were not significantly different from UTM (P > 0.05). Shear force values from the infraspinatus of D1 and OTM carcasses were not different from UTM. Flavour intensity was higher in several muscles from D1, D2, and D4 carcasses (P < 0.05), whereas flavour intensity was lower in several muscles from D3 (P < 0.05). Changes to eating quality attributes differed among mature grades; therefore, processors could potentially use the information presented here as a guide for utilizing cuts which retain high eating quality and separating those requiring tenderness intervention to reach consumer acceptability.
Synthesis and attempted reductions of bulky 1,3,5-triazapentadienyl groups 2 and 13 halide complexes
Authors: Pernik Indrek , Maitland Brant J. , Stasch Andreas , Jones Cameron
Published: October 2017

Three extremely bulky 1,3,5-triazapentadienes, ArNNNH (ArNNN = N{C(But)=N(Ar)}2; Ar = Mes (mesityl), Dep (2,6-diethylphenyl), or Dip (2,6-diisopropylphenyl)) have been prepared and structurally characterized. These are readily deprotonated, yielding a series of lithium and potassium triazapentadienyl complexes, one of which, (DipNNN)Li, has been structurally characterized. Similarly, three monomeric triazapentadienyl magnesium iodide complexes, (ArNNN)MgI(OEt2), and a dimeric calcium counterpart, {(MesNNN)Ca(THF)(μ-I)}2, have been prepared. Attempts to reduce the former gave homoleptic bis(triazapentadienyl) magnesium complexes, (ArNNN)2Mg (Ar = Mes or Dep) as the main products. One reaction also gave a very low yield of the magnesium(I) dimer, {(DepNNN)Mg–}2, which was structurally characterized. In related chemistry, two triazapentadienyl boron difluoride compounds, (ArNNN)BF2 (Ar = Mes or Dep), have been synthesized, and unsuccessful attempts have been made to reduce these to boron(I) heterocycles. For sake of comparison, attempts have been made to prepare a series of related amino-substituted β-diketiminato group 13 element(I) heterocycles. Although these were also not successful, several group 13 element(III) halide complexes incorporating this ligand class have been characterized.
Microscopic analysis of homogeneous electron gas by considering dipole–dipole interaction
Authors: Bordbar G. H. , Pouresmaeeli F.
Published: October 2017

Implying perturbation theory, the impact of the dipole–dipole interaction (DDI) on the thermodynamic properties of a homogeneous electron gas at zero temperature is investigated. Through the second quantization formalism, the analytic expressions for the ground state energy and the DDI energy are obtained. In this paper, the DDI energy has similarities with the previous works done by others. We show that its general behavior depends on density and the total angular momentum. Especially, it is found that the DDI energy has a highly state-dependent behavior. With the growth of density, the magnitude of DDI energy, which is found to be the summation of all energy contributions of the states with even and odd total angular momenta, grows linearly. It is also found that for the states with even and odd total angular momenta, the DDI energy contributions are corresponding to the positive and negative values, respectively. In particular, an increase of total angular momentum leads to decline in the magnitude of energy contribution. Therefore, the dipole–dipole interaction reveals distinct characteristics in comparison with central-like interactions.
Dicarbonyl stress and glyoxalase enzyme system regulation in human skeletal muscle
Authors: Mey Jacob T. , Blackburn Brian K. , Miranda Edwin R. , Chaves Alec B. , Briller Joan , Bonini Marcelo G. , Haus Jacob M.
Published: October 2017

Skeletal muscle insulin resistance is a hallmark of Type 2 diabetes (T2DM) and may be exacerbated by protein modifications by methylglyoxal (MG), known as dicarbonyl stress. The glyoxalase enzyme system composed of glyoxalase 1/2 (GLO1/GLO2) is the natural defense against dicarbonyl stress, yet its protein expression, activity, and regulation remain largely unexplored in skeletal muscle. Therefore, this study investigated dicarbonyl stress and the glyoxalase enzyme system in the skeletal muscle of subjects with T2DM (age: 56 ± 5 yr.; BMI: 32 ± 2 kg/m2) compared with lean healthy control subjects (LHC; age: 27 ± 1 yr.; BMI: 22 ± 1 kg/m2). Skeletal muscle biopsies obtained from the vastus lateralis at basal and insulin-stimulated states of the hyperinsulinemic (40 mU·m−2·min−1)–euglycemic (5 mM) clamp were analyzed for proteins related to dicarbonyl stress and glyoxalase biology. At baseline, T2DM had increased carbonyl stress and lower GLO1 protein expression (−78.8%), which inversely correlated with BMI, percent body fat, and HOMA-IR, while positively correlating with clamp-derived glucose disposal rates. T2DM also had lower NRF2 protein expression (−31.6%), which is a positive regulator of GLO1, while Keap1 protein expression, a negative regulator of GLO1, was elevated (207%). Additionally, insulin stimulation during the clamp had a differential effect on NRF2, Keap1, and MG-modified protein expression. These data suggest that dicarbonyl stress and the glyoxalase enzyme system are dysregulated in T2DM skeletal muscle and may underlie skeletal muscle insulin resistance. Whether these phenotypic differences contribute to the development of T2DM warrants further investigation.
Evidence for the presence in rainbow trout brain of amino acid-sensing systems involved in the control of food intake
Authors: Comesaña Sara , Velasco Cristina , Ceinos Rosa M. , López-Patiño Marcos A. , Míguez Jesús M. , Morais Sofia , Soengas José L.
Published: October 2017

To assess the hypothesis of central amino acid-sensing systems involved in the control of food intake in fish, we carried out two experiments in rainbow trout. In the first one, we injected intracerebroventricularly two different branched-chain amino acids (BCAAs), leucine and valine, and assessed food intake up to 48 h later. Leucine decreased and valine increased food intake. In a second experiment, 6 h after similar intracerebroventricular treatment we determined changes in parameters related to putative amino acid-sensing systems. Different areas of rainbow trout brain present amino acid-sensing systems responding to leucine (hypothalamus and telencephalon) and valine (telencephalon), while other areas (midbrain and hindbrain) do not respond to these treatments. The decreased food intake observed in fish treated intracerebroventricularly with leucine could relate to changes in mRNA abundance of hypothalamic neuropeptides [proopiomelanocortin (POMC), cocaine- and amphetamine-related transcript (CART), neuropeptide Y (NPY), and agouti-related peptide (AgRP)]. These in turn could relate to amino acid-sensing systems present in the same area, related to BCAA and glutamine metabolism, as well as mechanistic target of rapamycin (mTOR), taste receptors, and general control nonderepressible 2 (GCN2) kinase signaling. The treatment with valine did not affect amino acid-sensing parameters in the hypothalamus. These responses are comparable to those characterized in mammals. However, clear differences arise when comparing rainbow trout and mammals, in particular with respect to the clear orexigenic effect of valine, which could relate to the finding that valine partially stimulated two amino acid-sensing systems in the telencephalon. Another novel result is the clear effect of leucine on telencephalon, in which amino acid-sensing systems, but not neuropeptides, were activated as in the hypothalamus.
Central serotonin and the control of arterial blood pressure and heart rate in infant rats: influence of sleep state and sex
Authors: Magnusson Jennifer L. , Cummings Kevin J.
Published: October 2017

Sudden infant death syndrome (SIDS) is associated with serotonin (5-HT) neuron abnormalities. There is evidence of autonomic dysfunction during sleep in infants eventually succumbing to SIDS, as well as cardiovascular collapse before death. Neonatal rodents deficient in central 5-HT display hypotension and bradycardia. We hypothesized that central 5-HT reduces cardiac vagal tone and increases sympathetic vascular tone and, given the firing pattern of 5-HT neurons, that these effects are greater in quiet sleep (QS) than in active sleep (AS). We tested these hypotheses using 2-wk-old male and female rat pups lacking tryptophan hydroxylase-2 ( TPH2−/−) and wild-type (WT) littermates. Arterial blood pressure (ABP) and heart rate (HR) were measured over 3 h during periods of QS and AS. We also gave atropine or atenolol (each 1 mg/kg iv), or phentolamine (5, 50, and 500 μg/kg iv) to separate groups to assess the effects 5-HT deficiency on autonomic tone to the heart or sympathetic vascular tone, respectively. Compared with WT, male and female TPH2−/− pups had reduced ABP in QS but not in AS. Atropine induced a greater HR increase in female TPH2−/− than in female WT pups, an effect absent in male TPH2−/− pups. Both genotypes experienced the same atenolol-induced drop in HR. In males only, phentolamine induced a smaller decrease in the ABP of TPH2−/− pups compared with WT. These data suggest that central 5-HT maintains ABP in QS, and HR in both states. In males, central 5-HT facilitates sympathetic vascular tone, and in females it reduces cardiac vagal drive.
Identification of dual mechanisms mediating 5-hydroxytryptamine receptor 1F-induced mitochondrial biogenesis
Authors: Gibbs Whitney S. , Garrett Sara M. , Beeson Craig C. , Schnellmann Rick G.
Published: October 2017

Our laboratory recently made the novel observation that 5-hydroxytryptamine 1F (5-HT1F) receptor activation induces mitochondrial biogenesis (MB), the production of new, functional mitochondria, in vitro and in vivo. We sought to determine the mechanism linking the 5-HT1F receptor to MB in renal proximal tubule cells. Using LY344864 , a selective 5-HT1F receptor agonist, we determined that the 5-HT1F receptor is coupled to Gαi/o and induces MB through Gβγ-dependent activation of Akt, endothelial nitric oxide synthase (eNOS), cyclic guanosine-monophosphate (cGMP), protein kinase G (PKG), and peroxisome proliferator-activated receptor-γ coactivator-1α (PGC-1α). We also report that the 5-HT1F receptor signals through a second, Gβγ-dependent pathway that is linked by Akt phosphorylation of Raf. In contrast to the activated Akt pathway, Raf phosphorylation reduced extracellular signal regulated kinases (ERK1/2) and foxhead box O3a (FOXO3a) phosphorylation, suppressing an inhibitory MB pathway. These results demonstrate that the 5-HT1F receptor regulates MB through Gβγ-dependent dual mechanisms that activate a stimulatory MB pathway, Akt/eNOS/cGMP/PKG/PGC-1α, while simultaneously repressing an inhibitory MB pathway, Raf/MEK/ERK/FOXO3a. Novel mechanisms of MB provide the foundation for new chemicals that induce MB to treat acute and chronic organ injuries.
Two-Stage Dynamic Pricing and Advertising Strategies for Online Video Services
Authors: Li Zhi , Tan De-qing
Published: October 2017

As the demands for online video services increase intensively, the selection of business models has drawn the great attention of online providers. Among them, pay-per-view mode and advertising mode are two important resource modes, where the reasonable fee charge and suitable volume of ads need to be determined. This paper establishes an analytical framework studying the optimal dynamic pricing and advertising strategies for online providers; it shows how the strategies are influenced by the videos available time and the viewers’ emotional factor. We create the two-stage strategy of revenue models involving a single fee mode and a mixed fee-free mode and find out the optimal fee charge and advertising level of online video services. According to the results, the optimal video price and ads volume dynamically vary over time. The viewer’s aversion level to advertising has direct effects on both the volume of ads and the number of viewers who have selected low-quality content. The optimal volume of ads decreases with the increase of ads-aversion coefficient, while increasing as the quality of videos increases. The results also indicate that, in the long run, a pure fee mode or free mode is the optimal strategy for online providers.
(2 + 1)‐Dimensional Coupled Model for Envelope Rossby Solitary Waves and Its Solutions as well as Chirp Effect
Authors: Chen Xin , Yang Hongwei , Guo Min , Yin Baoshu
Published: October 2017

Using the method of multiple scales and perturbation method, a set of coupled models describing the envelope Rossby solitary waves in (2 + 1)‐dimensional condition are obtained, also can be called coupled NLS (CNLS) equations. Following this, based on trial function method, the solutions of the NLS equation are deduced. Moreover, the modulation instability of coupled envelope Rossby waves is studied. We can find that the stable feature of coupled envelope Rossby waves is decided by the value of S. Finally, learning from the concept of chirp in the optical soliton communication field, we study the chirp effect caused by nonlinearity and dispersion in the propagation of Rossby waves.
Simple Quantification of Pentosidine in Human Urine and Plasma by High-Performance Liquid Chromatography
Authors: Lee Ji Sang , Chung Yoon-Sok , Chang Sun Young , Jung Yi-Sook , Kim So Hee
Published: October 2017

Pentosidine is an advanced glycation end-product (AGE) and fluorescent cross-link compound. A simple high-performance liquid chromatographic (HPLC) method was developed for the detection and quantification of pentosidine in human urine and plasma. The mobile phase used a gradient system to improve separation of pentosidine from endogenous peaks, and chromatograms were monitored by fluorescent detector set at excitation and emission wavelengths of 328 and 378 nm, respectively. The retention time for pentosidine was 24.3 min and the lower limits of quantification (LLOQ) in human urine and plasma were 1 nM. The intraday assay precisions (coefficients of variation) were generally low and found to be in the range of 5.19–7.49% and 4.96–8.78% for human urine and plasma, respectively. The corresponding values of the interday assay precisions were 9.45% and 4.27%. Accuracies (relative errors) ranged from 87.9% to 115%. Pentosidine was stable in a range of pH solutions, human urine, and plasma. In summary, this HPLC method can be applied in future preclinical and clinical evaluation of pentosidine in the diabetic patients.
Development and Comparison of Fiber-Optic Beta Radiation Sensors with Different Diameters of Their Sensing Probes
Authors: Kim Rinah , Lee Sang Bin , Kim Jae Wook , Moon Joo Hyun
Published: October 2017

A fiber-optic radiation sensor (FORS) was developed for remote and real-time measurements of beta radiation from radioactive-contaminated soil. The sensing probe consisted of a bundle of organic scintillators and a mixture of epoxy resin to improve the detection efficiency. The measurement system consisted of a sensing probe with an aluminium foil reflector, a transmitting plastic optical fiber, and a light-measuring system comprising a photomultiplier tube, a preamplifier, a multichannel analyzer, and a laptop computer. Several sensing probes, whose dead-end diameters were 26 mm (bundle type I), 36 mm (bundle type II), and 46 mm (bundle type III), were prepared and characterized to identify the best sensing probe in terms of its radiation detection efficiency. The reproducibility of the FORS for the measurement of beta radiation was confirmed using a χ2-test. The measurements showed that the FORS sensing probe with a diameter 46 mm has the best detection performance.
In What Ways Do Synthetic Nucleotides and Natural Base Lesions Alter the Structural Stability of G-Quadruplex Nucleic Acids?
Authors: Sagi Janos
Published: October 2017

Synthetic analogs of natural nucleotides have long been utilized for structural studies of canonical and noncanonical nucleic acids, including the extensively investigated polymorphic G-quadruplexes (GQs). Dependence on the sequence and nucleotide modifications of the folding landscape of GQs has been reviewed by several recent studies. Here, an overview is compiled on the thermodynamic stability of the modified GQ folds and on how the stereochemical preferences of more than 70 synthetic and natural derivatives of nucleotides substituting for natural ones determine the stability as well as the conformation. Groups of nucleotide analogs only stabilize or only destabilize the GQ, while the majority of analogs alter the GQ stability in both ways. This depends on the preferredsynorantiN-glycosidic linkage of the modified building blocks, the position of substitution, and the folding architecture of the native GQ. Natural base lesions and epigenetic modifications of GQs explored so far also stabilize or destabilize the GQ assemblies. Learning the effect of synthetic nucleotide analogs on the stability of GQs can assist in engineering a required stable GQ topology, and exploring thein vitroaction of the single and clustered natural base damage on GQ architectures may provide indications for the cellular events.
Growth and Characterization of M-Plane GaN Thin Films Grown on γ-LiAlO2 (100) Substrates
Authors: Lin Yu-Chiao , Lo Ikai , Shih Hui-Chun , Chou Mitch M. C. , Schaadt D. M.
Published: October 2017

M-plane GaN thin films were grown on LiAlO2 substrates under different N/Ga flux ratios by plasma-assisted molecular beam epitaxy. An anisotropic growth of M-plane GaN was demonstrated against the N/Ga flux ratio. As the N/Ga flux ratio decreased by increasing Ga flux, the GaN surface trended to a flat morphology with stripes along [112-0]. According to high-resolution X-ray diffraction analysis, Li5GaO4 was observed on the interface between GaN and LiAlO2 substrate. The formation of Li5GaO4 would influence the surface morphology and crystal quality.
Identification and Characterization of the Diverse Stress-ResponsiveR2R3-RMYB Transcription Factor fromHibiscus sabdariffaL.
Authors: Mohamed Bahaeldeen Babikar , Aftab Beenish , Sarwar Muhammad Bilal , Rashid Bushra , Ahmad Zarnab , Hassan Sameera , Husnain Tayyab
Published: October 2017

Various regulatory proteins play a fundamental role to manage the healthy plant growth under stress conditions. Differential display reverse transcriptase PCR and random amplification of cDNA ends (RACE) was used to explore the osmotic stress-responsive transcripts. We identified and characterized the salt stress-responsive R2R3 type RMYB transcription factor fromHibiscus sabdariffawhich has an open reading frame of 690 bp, encoding 229 long chain amino acids. In silico analysis confirmed the conserved R2 and R3 domain as well as an NLS-1 localization site. The deduced amino acids of RMYB shared 83, 81, 80, 79, 72, 71, and 66% homology withArabidopsis thaliana,Glycine max,Oryza sativa,Zea maize,Malus domestica,Populus tremula × Populus alba, andMedicago sativaspecific MYB family, respectively. We observed the gene upregulation in stem, leaf, and root tissue in response to abiotic stress. Furthermore, RMYB gene was cloned into plant expression vector under CaMV35S promoter and transformed toGossypium hirsutum: a local cotton cultivar. Overexpression of RMYB was observed in transgenic plants under abiotic stresses which further suggests its regulatory role in response to stressful conditions. The RMYB transcription factor-overexpressing in transgenic cotton plants may be used as potential agent for the development of stress tolerant crop cultivars.
Mental Task Evaluation for Hybrid NIRS-EEG Brain-Computer Interfaces
Authors: Banville Hubert , Gupta Rishabh , Falk Tiago H.
Published: October 2017

Based on recent electroencephalography (EEG) and near-infrared spectroscopy (NIRS) studies that showed that tasks such as motor imagery and mental arithmetic induce specific neural response patterns, we propose a hybrid brain-computer interface (hBCI) paradigm in which EEG and NIRS data are fused to improve binary classification performance. We recorded simultaneous NIRS-EEG data from nine participants performing seven mental tasks (word generation, mental rotation, subtraction, singing and navigation, and motor and face imagery). Classifiers were trained for each possible pair of tasks using (1) EEG features alone, (2) NIRS features alone, and (3) EEG and NIRS features combined, to identify the best task pairs and assess the usefulness of a multimodal approach. The NIRS-EEG approach led to an average increase in peak kappa of 0.03 when using features extracted from one-second windows (equivalent to an increase of 1.5% in classification accuracy for balanced classes). The increase was much stronger (0.20, corresponding to an 10% accuracy increase) when focusing on time windows of high NIRS performance. The EEG and NIRS analyses further unveiled relevant brain regions and important feature types. This work provides a basis for future NIRS-EEG hBCI studies aiming to improve classification performance toward more efficient and flexible BCIs.
How Influential Are Mental Models on Interaction Performance? Exploring the Gap between Users’ and Designers’ Mental Models through a New Quantitative Method
Authors: Xie Bingjun , Zhou Jia , Wang Huilin
Published: October 2017

The objective of this study is to investigate the effect of the gap between two different mental models on interaction performance through a quantitative way. To achieve that, an index called mental model similarity and a new method called path diagram to elicit mental models were introduced. There are two kinds of similarity: directionless similarity calculated from card sorting and directional similarity calculated from path diagram. An experiment was designed to test their influence. A total of 32 college students participated and their performance was recorded. Through mathematical analysis of the results, three findings were derived. Frist, the more complex the information structures, the lower the directional similarity. Second, directional similarity (rather than directionless similarity) had significant influence on user performance, indicating that it is more effective in eliciting mental models using path diagram than card sorting. Third, the relationship between information structures and user performance was partially mediated by directional similarity. Our findings provide practitioners with a new perspective of bridging the gap between users’ and designers’ mental models.
Molecular Mechanisms Responsible for Increased Vulnerability of the Ageing Oocyte to Oxidative Damage
Authors: Mihalas Bettina P. , Redgrove Kate A. , McLaughlin Eileen A. , Nixon Brett
Published: October 2017

In their midthirties, women experience a decline in fertility, coupled to a pronounced increase in the risk of aneuploidy, miscarriage, and birth defects. Although the aetiology of such pathologies are complex, a causative relationship between the age‐related decline in oocyte quality and oxidative stress (OS) is now well established. What remains less certain are the molecular mechanisms governing the increased vulnerability of the aged oocyte to oxidative damage. In this review, we explore the reduced capacity of the ageing oocyte to mitigate macromolecular damage arising from oxidative insults and highlight the dramatic consequences for oocyte quality and female fertility. Indeed, while oocytes are typically endowed with a comprehensive suite of molecular mechanisms to moderate oxidative damage and thus ensure the fidelity of the germline, there is increasing recognition that the efficacy of such protective mechanisms undergoes an age‐related decline. For instance, impaired reactive oxygen species metabolism, decreased DNA repair, reduced sensitivity of the spindle assembly checkpoint, and decreased capacity for protein repair and degradation collectively render the aged oocyte acutely vulnerable to OS and limits their capacity to recover from exposure to such insults. We also highlight the inadequacies of our current armoury of assisted reproductive technologies to combat age‐related female infertility, emphasising the need for further research into mechanisms underpinning the functional deterioration of the ageing oocyte.
Ischaemic Preconditioning Suppresses Necrosis of Adipocutaneous Flaps in a Diabetic Rat Model Regardless of the Manner of Preischaemia Induction
Authors: Ottomann Christian , Küntscher Markus , Hartmann Bernd , Antonic Vlado
Published: October 2017

Ischaemic insult in the skin flaps is a major problem in reconstructive surgery particularly in patients with diabetes mellitus. Here, we sought to investigate the effectiveness of ischaemic preconditioning (IP) on diabetic skin flaps in rat animal model. Hundred Wistar rats (90 streptozotocin treated animals and 10 nondiabetic controls) were used. Diabetes mellitus was confirmed by measuring glucose level in blood, HbA1c, and ketonuria. We used blood vessel clamping, hind limb tourniquet, and NO donors (Spermine/NO complex) to induce short-term ischaemia of tissues that will be excised for skin flaps. Animals were followed for 5 days. Flaps were photographed at day 5 and percent of necrosis was determined using planimetry. Significant decrease in percent of necrotic tissue in all groups that received preconditioning was observed. Results show that ischaemic preconditioning suppresses flap necrosis in diabetic rats irrespective of direct or remote tissue IP and irrespective of chemically or physically induced preischaemia. Spermine/NO complex treatment 10 minutes after the flap ischaemia suppressed tissue necrosis. Treatment with NO synthase inhibitor L-NAME reversed effects of IP showing importance of NO for this process. We show that IP is a promising approach for suppression of tissue necrosis in diabetic flaps and potential of NO pathway as therapeutic target in diabetic flaps.
Evaluation of Electrospun Nanofiber-Anchored Silicone for the Degenerative Intervertebral Disc
Authors: Khandaker M. , Riahanizad S.
Published: October 2017

The nucleus pulposus (NP) substitution by polymeric gel is one of the promising techniques for the repair of the degenerative intervertebral disc (IVD). Silicone gel is one of the potential candidates for a NP replacement material. Electrospun fiber anchorage to silicone disc, referred as ENAS disc, may not only improve the biomechanical performances of the gel but it can also improve restoration capability of the gel, which is unknown. This study successfully produced a novel process to anchor any size and shape of NP gel with electrospun fiber mesh. Viscoelastic properties of silicone and ENAS disc were measured using standard experimental techniques and compared with the native tissue properties. Ex vivo mechanical tests were conducted on ENAS disc-implanted rabbit tails to the compare the mechanical stability between intact and ENAS implanted spines. This study found that viscoelastic properties of ENAS disc are higher than silicone disc and comparable to the viscoelastic properties of human NP. The ex vivo studies found that the ENAS disc restore the mechanical functionality of rabbit tail spine, after discectomy of native NP and replacing the NP by ENAS disc. Therefore, the PCL ENF mesh anchoring technique to a NP implant can have clinical potential.
IL-33-ST2 Axis in Liver Disease: Progression and Challenge
Authors: Sun Zijian , Chang Binxia , Gao Miaomiao , Zhang Jiyuan , Zou Zhengsheng
Published: October 2017

The new member of the IL-1 family, interleukin-33 (IL-33), participates in the progression of a variety of diseases through binding with its receptor ST2. Recently, much clinical evidence and experimental data have indicated that IL-33 is associated with various liver diseases. This review primarily addresses the relationship between IL-33 and several hepatic diseases. IL-33 can alleviate high-fat diet- (HFD-) induced hepatic steatosis and insulin resistance, and IL-33 acts as an alarmin, which quickly triggers the immune system to respond to virus invasion and toxic damage to the liver. However, when liver injury is chronic, IL-33 promotes Th2 reactions and hepatic stellate cell (HSC) activity, facilitating progression to liver fibrosis. The complicated functions of IL-33 should be considered before its clinical application.
Incidence and Risk Factors for Infections Requiring Hospitalization, Including Pneumocystis Pneumonia, in Japanese Patients with Rheumatoid Arthritis
Authors: Hashimoto Atsushi , Suto Shiori , Horie Kouichiro , Fukuda Hidefumi , Nogi Shinichi , Iwata Kanako , Tsuno Hirotaka , Ogihara Hideki , Kawakami Misato , Komiya Akiko , Furukawa Hiroshi , Matsui Toshihiro , Tohma Shigeto
Published: October 2017

Objective. Rheumatoid arthritis (RA) may be complicated by different infections, but risk factors for these are not fully elucidated. Here, we assessed the incidence of and risk factors for infections requiring hospitalization (IRH) including pneumocystis pneumonia (PCP) in patients with RA. Methods. We retrospectively surveyed all RA patients treated at our hospital from 2009 to 2013, for whom data were available on demographic features, medications, comorbidities, and severity of RA. Multivariate logistic regression analysis was applied to calculate adjusted odds ratios (ORs) for factors associated with the occurrence of IRH. Results. In a total of 9210 patient-years (2688 patients), there were 373 IRH (3.7/100 patient-years). Respiratory tract infections were most frequent (n=154, and additionally 16 PCP), followed by urinary tract infections (n=50). Significant factors for PCP included higher age (≥70 years; OR 3.5), male sex (6.6), underlying lung disease (3.0), use of corticosteroids (4.8), and use of biologics (5.4). Use of methotrexate (5.7) was positively associated with PCP but negatively with total infections (0.7). Additionally, functional disorders and higher RA disease activity were also related to total infections. Conclusions. Risk factors for infection should be taken into account when deciding treatment for the individual RA patient.
Anxiolytic Effect of Citrus aurantium L. in Crack Users
Authors: Chaves Neto Gabriel , Braga João Euclides Fernandes , Alves Mateus Feitosa , de Morais Pordeus Liana Clébia , Santos Sócrates Golzio dos , Scotti Marcus Tullius , Almeida Reinaldo N. , Diniz Margareth de Fátima Formiga Melo
Published: October 2017

The objective of this study was to investigate the anxiolytic effects of the essential oil (EO) of Citrus aurantium L. in patients experiencing crack withdrawal. This was developed with internal users in therapeutic communities in Paraíba, Brazil. The test population consisted of 51 volunteers, subdivided into three groups. To elicit anxiety, the Simulated Public Speaking (SPS) method was used. Physiological measures were assessed at specific phases during the experiment using appropriate equipment. Psychological measures of anxiety were assessed using the Trait‐State Anxiety Inventory (IDATE) and the Analog Smoke Scale (HAS). EO was administered by nebulization. The experiment was developed in individual sessions and consolidated to four phases. The results demonstrated that the test subjects in the groups that were given the EO maintained controlled anxiety levels during SPS, when compared to the Control Group (no treatment). Subjects who used the EO also maintained levels of “discomfort” and “cognitive impairment” during SPS. It was concluded that individuals who are experiencing internal crack cocaine withdrawal present high anxiety traits and that nebulization of the EO of Citrus aurantium L. provided an acute anxiolytic effect in crack cocaine users exposed to SPS.
High-Dose Compound Heat Map for 3D-Cultured Glioblastoma Multiforme Cells in a Micropillar and Microwell Chip Platform
Authors: Lee Dong Woo , Lee Sang-Yun , Doh Il , Ryu Gyu Ha , Nam Do-Hyun
Published: October 2017

Glioblastoma multiforme (GBM) is recognized as the most common and lethal form of central nervous system cancer. To cure GBM patients, many target-specific chemotherapeutic agents have been developing. However, 2D monolayer cell-based toxicity and efficacy tests did not efficiently screen agents due to the pool reflection of in vivo microenvironments (cell-to-cell and cell-to-extracellular matrix interaction). In this study, we used a 3D cell-based, high-throughput screening method reflecting the microenvironments using a micropillar and microwell chip platform to draw a high-dose heat map of the cytotoxicity and efficacy of 70 compounds, with two DMSO controls. Moreover, the high-dose heat map model compared the responses of four 3D-cultured patient-derived GBM cells and astrocytes to high dosages of compounds with respect to efficacy and cytotoxicity, respectively, to discern the most efficacious drug for GBM. Among the 70 compounds tested, cediranib (a potent inhibitor of vascular endothelial growth factor (VEGF) receptor tyrosine kinases) exhibited the lowest cytotoxicity to astrocytes and high efficacy to GBM cells in a high-dose heat map model.
Oxidative Modification of Blood Serum Proteins in Multiple Sclerosis after Interferon Beta and Melatonin Treatment
Authors: Adamczyk-Sowa Monika , Galiniak Sabina , Żyracka Ewa , Grzesik Michalina , Naparło Katarzyna , Sowa Paweł , Bartosz Grzegorz , Sadowska-Bartosz Izabela
Published: October 2017

Multiple sclerosis (MS) is a disease involving oxidative stress (OS). This study was aimed at examination of the effect of melatonin supplementation on OS parameters, especially oxidative protein modifications of blood serum proteins, in MS patients. The study included 11 control subjects, 14 de novo diagnosed MS patients with the relapsing‐remitting form of MS (RRMS), 36 patients with RRMS receiving interferon beta‐1b (250 μg every other day), and 25 RRMS patients receiving interferon beta‐1b plus melatonin (5 mg daily). The levels of N′‐formylkynurenine, kynurenine, dityrosine, carbonyl groups, advanced glycation products (AGEs), advanced oxidation protein products (AOPP), and malondialdehyde were elevated in nontreated RRSM patients. N′‐Formylkynurenine, kynurenine, AGEs, and carbonyl contents were decreased only in the group treated with interferon beta plus melatonin, while dityrosine and AOPP contents were decreased both in the group of patients treated with interferon beta and in the group treated with interferon beta‐1b plus melatonin. These results demonstrate that melatonin ameliorates OS in MS patients supporting the view that combined administration of interferon beta‐1b and melatonin can be more effective in reducing OS in MS patients than interferon beta‐1b alone.
A Study on the Mechanical Properties of the Representative Volume Element in Fractal Porous Media
Authors: Liu Jianjun , Wu Mingyang , Zhu Zhengwen , Shao Zuliang
Published: October 2017

Natural porous structure is extremely complex, and it is of great significance to study the macroscopic mechanical response of the representative volume element (RVE) with the microstructure of porous media. The real porous media RVE is generated by an improved quartet structure generation set (QSGS), and the connectivity of the reconstructed porous media models is analyzed. The fractal dimension of the RVE is calculated by the box-counting method, which considers the different porosity, different fractal dimension, and different mechanical properties of the matrix. Thus, the stress-strain curves of the RVE in the elastoplastic stage under different conditions are obtained. The results show that when the matrix mechanics are consistent, the mechanical properties of the porous media RVE are negatively correlated with the porosity and fractal dimension; when the difference between the porosity and fractal dimension increases, the trend is more obvious. The mechanical properties of the RVE have a positive correlation with the modulus of elasticity of the matrix, though the correlation with Poisson’s ratio of the matrix is weak. The fractal dimension of complex porous media can better predict the RVE mechanical characteristics than the porosity.
The Cascadic Multigrid Method of the Weak Galerkin Method for Second‐Order Elliptic Equation
Authors: Sun Shi , Huang Ziping , Wang Cheng , Guo Liming
Published: October 2017

This paper is devoted to the analysis of the cascadic multigrid algorithm for solving the linear system arising from the weak Galerkin finite element method. The proposed cascadic multigrid method is optimal for conjugate gradient iteration and quasi‐optimal for Jacobi, Gauss‐Seidel, and Richardson iterations. Numerical results are also provided to validate our theoretical analysis.
Visual Map Construction Using RGB-D Sensors for Image-Based Localization in Indoor Environments
Authors: Feng Guanyuan , Ma Lin , Tan Xuezhi
Published: October 2017

RGB-D sensors capture RGB images and depth images simultaneously, which makes it possible to acquire the depth information at pixel level. This paper focuses on the use of RGB-D sensors to construct a visual map which is an extended dense 3D map containing essential elements for image-based localization, such as poses of the database camera, visual features, and 3D structures of the building. Taking advantage of matched visual features and corresponding depth values, a novel local optimization algorithm is proposed to achieve point cloud registration and database camera pose estimation. Next, graph-based optimization is used to obtain the global consistency of the map. On the basis of the visual map, the image-based localization method is investigated, making use of the epipolar constraint. The performance of the visual map construction and the image-based localization are evaluated on typical indoor scenes. The simulation results show that the average position errors of the database camera and the query camera can be limited to within 0.2 meters and 0.9 meters, respectively.
Body Posture Asymmetry in Prematurely Born Children at Six Years of Age
Authors: Walicka-Cupryś Katarzyna , Drzał-Grabiec Justyna , Rachwał Maciej , Piwoński Paweł , Perenc Lidia , Przygoda Łukasz , Zajkiewicz Katarzyna
Published: October 2017

Aims. The purpose of the study was to assess body posture asymmetries in the standing and sitting position in prematurely born children at six years of age. Study Design and Subjects. We measured trunk symmetry in coronal plane. The study was carried out in a group of 101 children, aged 6-7 years, mean age of 6.63, including 50 preterm children born at gestational age <32 weeks (preterm group) and 51 full-term children (control group). Outcome Measures. Trunk symmetry in coronal plane was measured using photogrammetric technique with Mora 4G CQ Elektronik. The subjects were examined in standing and sitting position. Statistical analyses were carried out using Shapiro-Wilk W-test, Student’s t-test, Mann–Whitney U test, and Pearson’s chi-squared test. Statistical significance was assumed at p<0.05. Results. No significant differences were found between the groups in the asymmetries identified in the relevant anthropometric points, relative to the position assumed during the examination or to the subjects’ sex. Conclusions. There are no significant differences in body posture in the coronal plane, between preterm children and full-term children. Premature birth does not have adverse effects related to body posture asymmetry in preterm children at the age of six.
Analysis of Pipe‐Roof in Tunnel Exiting Portal by the Foundation Elastic Model
Authors: Luo Yanbin , Chen Jianxun , Liu Bao , Chen Lijun , Xie Jiangtao
Published: October 2017

The Pasternak double‐parameter elastic foundation model of pipe‐roof during the construction of tunnel exits is first established. Based on the portal project of Hanjiashan highway tunnel, an inclinometer is adopted to measure the settlement deformation of a pipe‐roof and demonstrates the deformation law in tunnel exiting portals. The formulas for calculating the deflection and internal forces are derived to analyze the deformation of the pipe‐roof in each excavation stage, and the results are compared with field monitoring data. Finally, the influences of excavation height, excavation footage, and stiffness of the pipe‐roof on the support effect are investigated. Analysis indicates that the longitudinal settlement curve shows a groove distribution, which can be divided into five stages: micro, rapid, continuous, resilience, and stable deformation. Moreover, the subsidence rate reaches its maximum at the tunnel face. The influence of tunnel excavation on the deformation mainly has a range of 1.5 times the excavation height. To control the deflection of the pipe‐roof, excavation height should be controlled in the range of 3.5 m, excavation footage should be controlled in the range of 1–1.4 m, and the diameter and thickness of the selected pipe‐roof should be in the ranges of 89–159 mm and 5–8 mm, respectively.
Assessment of the Efficacy of Home Remedial Methods to Improve Drinking Water Quality in Two Major Aquifer Systems in Jaffna Peninsula, Sri Lanka
Authors: Wijeyaratne W. M. Dimuthu Nilmini , Subanky Suvendran
Published: October 2017

Chunnakam and Vadamaradchi are two major aquifer systems in Jaffna Peninsula, Sri Lanka. This study was performed to compare water quality in the domestic wells in these aquifers and to assess the efficacy of household water treatments for treating contaminated water. Replicate well water samples were collected from each aquifer and pH, dissolved oxygen (DO), conductivity, total dissolved solids (TDS), salinity, temperature, total solids (TS), total hardness (TH), chemical oxygen demand (COD), oil and grease (OG), nitrate N (N), and total phosphate (TP) were measured. The sampled water from the domestic wells was filtered through commercial mineral filter andMoringa oleiferaleaf powder and boiled at 100°C for 10 minutes and the TH, OG, N, and TP were measured. Both OG and N in Chunnakam were significantly higher and the DO were significantly lower than those of Vadamaradchi. TH, N, and OG of some wells exceeded the drinking water quality standards established by Sri Lanka Standards Institution.Moringa oleiferaleaf powder filtration reduced N significantly and filtering through commercial mineral filter reduced OG, TH, and N significantly. Boiling at 100°C could remove TH significantly but may cause significant increase in N which might result in health impacts.
Influence of Dexamethasone on Some Reproductive Hormones and Uterine Progesterone Receptor Localization in Pregnant Yankasa Sheep in Semiarid Zones of Nigeria
Authors: Yahi Dauda , Ojo Nicholas Adetayo , Mshelia Gideon Dauda
Published: October 2017

Dexamethasone is widely used in both veterinary and human medical practices. However, it seems to cause some deleterious effects on pregnancy probably by causing changes in the reproductive hormone levels and their corresponding receptor concentrations. This study investigated the effects of dexamethasone on these parameters. Twenty healthy adult Yankasa sheep comprising 18 ewes and 2 rams were used for this study. Pregnancies were achieved by natural mating after estrus synchronization. Dexamethasone was administered at 0.25 mg/kg body weight on days 1, 3, and 5 during first trimester; days 51, 53, and 55 during second trimester; and days 101, 103, and 105 during the third trimester. Blood samples were collected biweekly for hormonal assay. Uterine biopsies were harvested through caesarean section for immunohistochemical analysis. Results showed that dexamethasone significantly (p<0.05) decreased progesterone concentrations and caused abortion in Yankasa sheep but had no significant (p>0.05) effect on estrogen, while progesterone receptors (PR) were upregulated. The abortion could probably be due to decreased progesterone concentrations as a consequence of the adverse effects on placenta. The PR upregulation may be a compensatory mechanism to increase progesterone sensitivity. It was concluded that dexamethasone should not be used in advanced pregnancy in Yankasa sheep.
Overt Lower Gastrointestinal Bleeding and Pseudotumor: A Rare Presentation of Cytomegalovirus Infection
Authors: Agrawal Akanksha , Jain Deepanshu , Siddique Sameer
Published: October 2017

Cytomegalovirus (CMV) is a ubiquitous organism which can infect multiple organs of the body. In an immunocompromised patient, it can have a myriad of gastrointestinal manifestations. We report a case of recurrent hematochezia and concomitant pseudotumor in an AIDS (acquired immunodeficiency syndrome) patient attributable to CMV infection. A 62-year-old man with a history of AIDS, noncompliant with highly active antiretroviral therapy (HAART), presented with bright red blood per rectum. Index colonoscopy showed presence of multiple ulcers, colonic stenosis, and mass-like appearing lesion. Biopsy confirmed CMV infection and ruled out malignancy. Cessation of dual antiplatelet therapy and compliance with HAART lead to clinical cessation of bleeding and endoscopic healing of ulcers with complete resolution of colon mass on follow-up colonoscopy.