High serum osteopontin levels are associated with prevalent fractures and worse lipid profile in post-menopausal women with type 2 diabetes

Abstract

Purpose

Patients with type 2 diabetes (T2DM) have increased fracture risk. Osteopontin (OPN) is a protein involved in bone remodeling and inflammation. The aim of this study was to evaluate the association of OPN with fracture prevalence and with metabolic parameters in post-menopausal women with T2DM.

Methods

Sixty-four post-menopausal women with T2DM (age 67.0 ± 7.8 years, diabetes duration 8.9 ± 6.7 years), enrolled in a previous study, were followed up (3.6 ± 0.9 years). Previous fragility fractures were recorded. The FRAX score (without BMD) was calculated and biochemical parameters (plasma glucose, HbA1c, lipid profile and renal function) were assessed. Serum 25OH-vitamin D, calcium, PTH and OPN were evaluated at baseline. The association between OPN and fracture prevalence at baseline was evaluated by a logistic model.

Results

OPN levels were higher in patients with previous fractures (n.25) than in patients without previous fractures at baseline (n.39) (p = 0.006). The odds of having fractures at baseline increased by 6.7 (1.9–31.4, 95% CI, p = 0.007) for each increase of 1 ng/ml in OPN levels, after adjustment for vitamin D and HbA1c levels. Fracture incidence was 4.7%. Higher OPN associated with a decrease in HDL-cholesterol (p = 0.048), after adjustment for age, basal HDL-cholesterol, basal and follow-up HbA1c and follow-up duration. 25OH-vitamin D associated with an increase in FRAX-estimated probability of hip fracture at follow-up (p = 0.029), after adjustment for age, 25OH-vitamin D and time.

Conclusions

In post-menopausal women with T2DM, OPN might be a useful marker of fracture and worse lipid profile.

https://ift.tt/2JLKMOU

Scholar : New articles have been published for Journal of Natural History, Volume 52, Issue 23-24

The online platform for Taylor & Francis Online content The following articles have been newly published in the issue Journal of Natural History, Volume 52, Issue 23-24 on Taylor & Francis Online: Original Articles Stegana (Oxyphortica) convergens species group (Diptera: Drosophilidae) from the Oriental region, with morphological and molecular evidence Jia Huang, Nan-Nan Wang, Yuan Zhang, Hong-Wei Chen Pages: 1473-1492 | DOI: 10.1080/00222933.2018.1478010 Expulsion and consumption of male ejaculates by promiscous female Euxesta eluta and Euxesta mazorca (Diptera: Ulidiidae) Solana Abraham, Christian Rodríguez, Andrea Oviedo, Gabriela Murúa, Juan Rull Pages: 1493-1508 | DOI: 10.1080/00222933.2018.1478460 Rediscovery of Disepyris semiruber (Kieffer) (Hymenoptera: Bethylidae) in Southern Africa, with first description of the male Celso O. Azevedo, Simon van Noort, David G. Notton Pages: 1537-1549 | DOI: 10.1080/00222933.2018.1478997 The issue is in progress. To view all articles already published in this issue, please visit: https://www.tandfonline.com/toc/tnah20/52/23-24 Hoping to have your article read by anyone, anywhere and at any time? Find out more about publishing open access with Ecosystem Health and Sustainability. To update which email alerts you receive, manage your alerts within the My Account area. You can also unsubscribe from this alert with one click. If you need any further help, please contact us at support@tandfonline.com Please do not reply to this email. To ensure that you receive your alerts and information from Taylor & Francis Online, please add "alerts@tandfonline.com" and "info@tandfonline.com" to your safe senders list. Taylor & Francis, an Informa business. Taylor & Francis is a trading name of Informa UK Limited, registered in England under no. 1072954. Registered office: 5 Howick Place, London, SW1P 1WG.

Aptamer cell sensor based on porous graphene oxide decorated ion-selective-electrode: Double sensing platform for cell and ion

Publication date: 15 October 2018
Source:Biosensors and Bioelectronics, Volume 117
Author(s): Rong Zhang, Yajun Gu, Zhongrong Wang, Yueguo Li, Qingjie Fan, Yunfang Jia
Enlightened by the emerging cell-ion detection based on ion-selective-electrode (ISE), an aptamer capturing and ISE transducing (AC&IT) strategy is proposed on the porous graphene oxide (PGO) decorated ISE (PGO-ISE), its performances in both cell and ion detections are examined by use of AS1411 targeted A549 cell detection and iodide-ISE as proof-of-concept. Firstly, GO flakes, exfoliated from graphite by modified Hummers method, are cross-linked by thiourea mediated hydrothermal process, to 3-dimension networked PGO which is identified by scanning-electron-microscope, UV–visible absorbance and X-ray photoelectron spectroscopy; its enhancing effect for cell capturing is evaluated by microscopy. Then, PGO-ISE is constructed by drop-coating PGO film on the surface of ISE and followed by covalently anchoring AS1411. Electrochemistry measurements for different state ISE (blank, PGO coated, AS1411 anchored and A549 captured) are performed by our home-made ISE-measuring system. It is demonstrated that the best cell-sensitivity in buffer is − 25.21 mV/log10CA549 (R² = 0.91), resolution in blood is 10 cells/ml. Interestingly, due to PGO's scaffold protection to the ionophore, I^--sensitivity is preserved as − 42.98 mV/pI (R² = 0.95, pI = -log10(CI)). Theoretical explanations are provided for the double-sensing phenomenon according to basic ISE principle. It is believed the PGO-ISE based aptamer cell sensor will be a promising experimental means for biomedical researches.



https://ift.tt/2lhBEDa

Accounting for water levels and black carbon-inclusive sediment-water partitioning of organochlorines in Lesser Himalaya, Pakistan using two-carbon model

Abstract

This study was designed to monitor organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in riverine water of Lesser Himalaya along the altitude. Further, the sediment-water partitioning employing organic carbon and black carbon models were assessed. Results revealed higher water levels of organochlorine pesticides (0.07–41.4 ng L⁻¹) and polychlorinated biphenyls (0.671–84.5 ng L⁻¹) in Lesser Himalayan Region (LHR) of Pakistan. Spatially, elevated levels were observed in the altitudinal zone (737–975 masl) which is influenced by anthropogenic and industrial activities. Sediment-water partitioning of OCPs and PCBs were deduced using field data by employing one-carbon (f_OCK_OC) and two-carbon Freundlich models (f_OCK_OC + f_BCK_BCC_W^nF−1). Results suggested improved measured vs predicted model concentrations when black carbon was induced in the model and suggested adsorption to be the dominant mechanism in phase partitioning of organochlorines in LHR.

https://ift.tt/2HZarxP

The impacts of environmental governance on political turnover of municipal party secretary in China

Abstract

Political incentive is one of the most efficient methods to promote local officials to push for both economic growth and environmental progress in the context of China. Since previous scholars have never investigated the relationships between political turnover and environmental governance at the municipal level, in this work, we proxy pollution by SO₂, COD, SOOT, and NHx and examine whether environmental performance affects the political turnover of the municipal party secretary by exploiting a panel conditional logit with a fixed-effect model for the period 2002–2013. The results indicate that environmental performance does not significantly impact the turnover of municipal party secretaries, offering evidence that an increase of SO₂ is associated with the likelihood of promotion under the panel multinomial logit approach. However, a higher GDP growth rate plays the determinant factor affecting the promotion of China's municipal party secretaries. Specific policy recommendations are proposed in accordance with our empirical findings.

https://ift.tt/2K2P0kv

Micro-bubbles enhanced breakage warning for hollow fiber membrane integrity with a low-cost real-time monitoring device

Abstract

A low-cost device was developed to monitor the integrity of hollow fiber membrane by real-time online detecting and measuring air bubbles in the permeate flow. When a breakage occurs in the fiber membrane system, air bubbles will find their ways to enter the permeate flow. The monitoring device consists of two pairs of platinum probes attached to a pipe, along which the permeate flows. Membrane's breakage was identified by the voltage changes between the two pairs of probes when air bubbles in the permeate touch them. There was no addition of any other chemicals or materials into the system that would jeopardize final products of the membrane process. Experimental results showed that the voltage signal changes before and after a breach of membrane were obvious in the normal operation conditions. The smallest diameter of the bubbles that can be detected by the monitoring device was 50 μm, which was captured and identified with a high-speed camera. Furthermore, the sensitivity of device with two pairs of probes improved by 5~9% over that with one pair of probes. Finally, cost of the proposed device was roughly estimated only about 70 US dollars and the detection result was highly consistent with that obtained with the prevailing particle counters of several thousand US dollars.

https://ift.tt/2HUUEQF

Multi-channel silk sponge mimicking bone marrow vascular niche for platelet production

Publication date: September 2018
Source:Biomaterials, Volume 178
Author(s): Lorenzo Tozzi, Pierre-Alexandre Laurent, Christian A. Di Buduo, Xuan Mu, Angelo Massaro, Ross Bretherton, Whitney Stoppel, David L. Kaplan, Alessandra Balduini
In the bone marrow, the interaction of progenitor cells with the vasculature is fundamental for the release of blood cells into circulation. Silk fibroin, derived from Bombyx mori silkworm cocoons, is a promising protein biomaterial for bone marrow tissue engineering, because of its tunable architecture and mechanical properties, the capacity to incorporate labile compounds without loss of bioactivity and the demonstrated ability to support blood cell formation without premature activation. In this study, we fabricated a custom perfusion chamber to contain a multi-channel lyophilized silk sponge mimicking the vascular network in the bone marrow niche. The perfusion system consisted in an inlet and an outlet and 2 splitters that allowed funneling flow in each single channel of the silk sponge. Computational Fluid Dynamic analysis demonstrated that this design permitted confined flow inside the vascular channels. The silk channeled sponge supported efficient platelet release from megakaryocytes (Mks). After seeding, the Mks localized along SDF-1α functionalized vascular channels in the sponge. Perfusion of the channels allowed the recovery of functional platelets as demonstrated by increased PAC-1 binding upon thrombin stimulation. Further, increasing the number of channels in the silk sponge resulted in a proportional increase in the numbers of platelets recovered, suggesting applicability to scale-up for platelet production. In conclusion, we have developed a scalable system consisting of a multi-channeled silk sponge incorporated in a perfusion chamber that can provide useful technology for functional platelet production ex vivo.



https://ift.tt/2JJF8Nf

Producing anti-inflammatory macrophages by nanoparticle-triggered clustering of mannose receptors

Publication date: September 2018
Source:Biomaterials, Volume 178
Author(s): Jingjing Gan, Yunyan Dou, Yurong Li, Zhenzhen Wang, Lintao Wang, Shang Liu, Qiu Li, Heran Yu, Chunyan Liu, Congwei Han, Zhen Huang, Junfeng Zhang, Chunming Wang, Lei Dong
Macrophages are highly plastic cells that can either mediate or suppress inflammation, depending on their cellular phenotype and cytokine secretion. Inducing macrophages from an inflammatory ('M1') to anti-inflammatory ('M2') phenotype has significant implications for the treatment of inflammatory diseases and regeneration of injured tissues. Although certain cytokines, such as interleukin-4 and -13, are known to induce this phenotypic switch, their therapeutic use in vivo has both safety and efficacy concerns. Here, we demonstrate an alternative approach to change macrophage phenotype from M1 to M2, through inducing the clustering of mannose receptors (MR) on the cell surface, by using carbohydrate-presenting substrates. We prepared and screened glucomannan-decorated silicon oxide of different sizes ranging from 10 to 1000 nm, and identified one type (KSiNP30) that could potently induce MR clustering on macrophages and thereby stimulated the cells into an M2 phenotype – as an unexpected consequence of MR activation. Further administration of KSiNP30 in a murine model of inflammatory bowel disease efficiently alleviated the colitis symptoms, indicating the translational potential of our finding for therapeutic applications. In summary, we report for the first time an approach to modulate cellular immune responses by manipulating the assembly of cell-surface receptors, without the aid of cytokines. Our approach may provide insights for the development of new anti-inflammatory therapies.



https://ift.tt/2M1IGqN

CD4 T-cells regulate angiogenesis and myogenesis

Publication date: September 2018
Source:Biomaterials, Volume 178
Author(s): Brian J. Kwee, Erica Budina, Alexander J. Najibi, David J. Mooney
Ischemic diseases, such as peripheral artery disease, affect millions of people worldwide. While CD4⁺ T-cells regulate angiogenesis and myogenesis, it is not understood how the phenotype of these adaptive immune cells regulate these regenerative processes. The secreted factors from different types of CD4⁺ T-cells (Th1, Th2, Th17, and Treg) were utilized in a series of in vitro assays and delivered from an injectable alginate biomaterial into a murine model of ischemia to study their effects on vascular and skeletal muscle regeneration. Conditioned medium from Th2 and Th17  T-cells enhanced angiogenesis in vitro and in vivo, in part by directly stimulating endothelial sprouting. Th1 conditioned medium induced vascular regression in vitro and provided no benefit to angiogenesis in vivo. Th1, Th2, and Th17 conditioned medium, to varying extents, enhanced muscle precursor cell proliferation and inhibited their differentiation in vitro, and prolonged early stages of muscle regeneration in vivo. Treg conditioned medium had a moderate or no effect on these processes in vitro and no discernible effect in vivo. These findings suggest that Th2 and Th17 T-cells may enhance angiogenesis and myogenesis in ischemic injuries, which may be useful in the design of immunomodulatory biomaterials to treat these diseases.



https://ift.tt/2JK8knb

Comparative immunological study of the snail Physella acuta (Hygrophila, Pulmonata) reveals shared and unique aspects of gastropod immunobiology

Publication date: September 2018
Source:Molecular Immunology, Volume 101
Author(s): Jonathan H. Schultz, Lijing Bu, Coen M. Adema
The freshwater snail Physella acuta was selected to expand the perspective of comparative snail immunology. Analysis of Physella acuta, belonging to the Physidae, taxonomic sister family to Planorbidae, affords family-level comparison of immune features characterized from Biomphalaria glabrata, the model snail often used to interpret general gastropod immunity. To capture constitutive and induced immune sequences, transcriptomes of an individual Physella acuta snail, 12 h post injection with bacteria (Gram –/+) and one sham-exposed snail were recorded with 454 pyrosequencing. Assembly yielded a combined reference transcriptome containing 24,288 transcripts. Additionally, genomic Illumina reads were obtained (∼15-fold coverage). Recovery of transcripts for two macin-like antimicrobial peptides (AMPs), 12 aplysianins, four LBP/BPIs and three physalysins indicated that Physella acuta shares a similar organization of antimicrobial defenses with Biomphalaria glabrata, contrasting a modest AMP arsenal with a diverse set of antimicrobial proteins. The lack of predicted transmembrane domains in all seven Physella acuta PGRP transcripts supports the notion that gastropods do not employ cell-bound PGRP receptors, different from ecdysozoan invertebrates yet similar to mammals (vertebrate deuterostomes). The well-documented sequence diversification by Biomphalaria glabrata FREPs (immune lectins comprising immunoglobulin superfamily domains and fibrinogen domains), resulting from somatic mutations of a large FREP gene family is hypothesized to be unique to Planorbidae; Physella acuta revealed just two bonafide FREP genes and these were not diversified. Furthermore, the flatworm parasite Echinostoma paraensei, confirmed here to infect both snail species, did not evoke from Physella acuta the abundant expression of FREP proteins at 2, 4 and 8 days post exposure that was previously observed from Biomphalaria glabrata. The Physella acuta reference transcriptome also revealed 24 unique transcripts encoding proteins consisting of a single fibrinogen-related domain (FReDs), with a short N-terminal sequence encoding either a signal peptide, transmembrane domain or no predicted features. The Physella acuta FReDs are candidate immune genes based on implication of similar sequences in immunity of bivalve molluscs. Overall, comparative analysis of snails of sister families elucidated the potential for taxon-specific immune features and investigation of strategically selected species will provide a more comprehensive view of gastropod immunity.



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SIRT2 Promotes the Migration and Invasion of Gastric Cancer through RAS/ERK/JNK/MMP-9 Pathway by Increasing PEPCK1-Related Metabolism

Publication date: July 2018
Source:Neoplasia, Volume 20, Issue 7
Author(s): Yang Li, Mingming Zhang, Robert G. Dorfman, Yida Pan, Dehua Tang, Lei Xu, Zhenguo Zhao, Qian Zhou, Lixing Zhou, Yuming Wang, Yuyao Yin, Shanshan Shen, Bo Kong, Helmut Friess, Shimin Zhao, Lei Wang, Xiaoping Zou
Metastasis is the most important feature of gastric cancer (GC) and the most widely recognized reason for GC-related deaths. Unfortunately, the underlying mechanism behind this metastasis remains unknown. Mounting evidence suggests the dynamic regulatory role of sirtuin2 (SIRT2), a histone deacetylase (HDAC), in cell migration and invasion. The present study aims to evaluate the biological function of SIRT2 in GC and identify the target of SIRT2 as well as evaluate its therapeutic efficacy. We found that SIRT2 was upregulated in GC tissues compared to adjacent normal tissues, and this was correlated with reduced patient survival. Although CCK8 and colony-formation assays showed that SIRT2 overexpression marginally promoted proliferation in GC cell lines, SIRT2 knockdown or treatment with SirReal2 decreased the migration and invasion of GC cells. We demonstrated both in vitro and in vivo that SirReal2 could inhibit the deacetylation activity of SIRT2 and its downstream target PEPCK1, which is related to mitochondrial metabolism and RAS/ERK/JNK/MMP-9 pathway. Taken together, these results demonstrate for the first time that SirReal2 selectively targets SIRT2 and decreases migration as well as invasion in human GC cells. SirReal2 therefore shows promise as a new drug candidate for GC therapy.



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Aging of human alpha rhythm

Publication date: September 2018
Source:Neurobiology of Aging, Volume 69
Author(s): Maria G. Knyazeva, Elham Barzegaran, Vladimir Y. Vildavski, Jean-François Demonet
Alpha rhythm (AR) changes are the most pronounced electroencephalogram phenomenon in the aging brain. We analyzed them based on the inherent AR structure obtained by parallel factor analysis decomposition in the cortical source space. AR showed a stable multicomponent structure in 78% of sixty 20- to 81-year-old healthy adults. Typically, it consists of 2 components. The distribution of the higher frequency occipito-parietal component widens with age, with its maximum moving from BA18/19 to BA37. The low-frequency component originating from the occipito-temporal regions in young adults also moves anteriorly with age, while maintaining its maximum within BA37. Both components slow down by 1 Hz over the adult lifespan. The multicomponent AR is more common in younger subjects, whereas a single-component AR in older subjects. This uneven occurrence as well as the increasing spatial and frequency overlaps between components suggest transformation of the multicomponent AR into the single-component AR with age. A detailed knowledge of AR component structure would be useful to monitor age-related neurodegenerative processes in humans.



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The relation between Scrabble expertise and brain aging as measured with EEG brain signal variability

Publication date: September 2018
Source:Neurobiology of Aging, Volume 69
Author(s): Hongye Wang, Penny M. Pexman, Gary Turner, Filomeno Cortese, Andrea B. Protzner
Recent empirical work suggests that the dynamics of brain function, as measured by brain signal variability, differs between younger and older adults. We extended this work by examining how the relationship between brain signal variability and age is altered in the context of expertise. We recorded electroencephalography from Scrabble experts and controls during a visual word recognition task. To measure variability, we used multiscale entropy, which emphasizes the way brain signals behave over a range of timescales and can differentiate the variability of a complex system (the brain) from a purely random system. We replicated previously identified shifts from long-range interactions among neural populations to more local processing in late adulthood. In addition, we demonstrated an age-related increase in midrange neural interactions for experts, suggesting greater maintenance of network integration into late adulthood. Our results indicate that expertise-related differences in the context of age and brain dynamics occur across different timescales and that these differences are linked to task performance.



https://ift.tt/2lhdgl6

Non-linear transfer characteristics of stimulation and recording hardware account for spurious low-frequency artifacts during amplitude modulated transcranial alternating current stimulation (AM-tACS)

Publication date: 1 October 2018
Source:NeuroImage, Volume 179
Author(s): Florian H. Kasten, Ehsan Negahbani, Flavio Fröhlich, Christoph S. Herrmann
Amplitude modulated transcranial alternating current stimulation (AM-tACS) has been recently proposed as a possible solution to overcome the pronounced stimulation artifact encountered when recording brain activity during tACS. In theory, AM-tACS does not entail power at its modulating frequency, thus avoiding the problem of spectral overlap between brain signal of interest and stimulation artifact. However, the current study demonstrates how weak non-linear transfer characteristics inherent to stimulation and recording hardware can reintroduce spurious artifacts at the modulation frequency. The input-output transfer functions (TFs) of different stimulation setups were measured. Setups included recordings of signal-generator and stimulator outputs and M/EEG phantom measurements. 6^th-degree polynomial regression models were fitted to model the input-output TFs of each setup. The resulting TF models were applied to digitally generated AM-tACS signals to predict the frequency of spurious artifacts in the spectrum. All four setups measured for the study exhibited low-frequency artifacts at the modulation frequency and its harmonics when recording AM-tACS. Fitted TF models showed non-linear contributions significantly different from zero (all p < .05) and successfully predicted the frequency of artifacts observed in AM-signal recordings. Results suggest that even weak non-linearities of stimulation and recording hardware can lead to spurious artifacts at the modulation frequency and its harmonics. These artifacts were substantially larger than alpha-oscillations of a human subject in the MEG. Findings emphasize the need for more linear stimulation devices for AM-tACS and careful analysis procedures, taking into account low-frequency artifacts to avoid confusion with effects of AM-tACS on the brain.



https://ift.tt/2ldEzMT

Chemical exchange saturation transfer MRI contrast in the human brain at 9.4 T

Publication date: 1 October 2018
Source:NeuroImage, Volume 179
Author(s): Moritz Zaiss, Mark Schuppert, Anagha Deshmane, Kai Herz, Philipp Ehses, Lars Füllbier, Tobias Lindig, Benjamin Bender, Ulrike Ernemann, Klaus Scheffler
PurposeThe high chemical shift separation at 9.4 T allows for selective saturation of proton pools in exchange with water protons. For the first time, highly selective and comprehensive chemical exchange saturation transfer (CEST) experiments were performed in the human brain at 9.4 T. This work provides insight into CEST signals in the human brain in comparison with existing animal studies, as well as with CEST effects in vivo at lower field strengths.MethodsA novel snapshot-CEST method for human brain scans at 9.4 T was optimized and employed for highly-spectrally-resolved (95 offsets) CEST measurements in healthy subjects and one brain tumor patient. Reproducibility and stability between scans was verified in grey and white matter after B0, B1, and motion correction of the acquired 3D CEST volumes. Two-step Lorentzian fitting was used to further improve separation of spectrally discernible signals to create known and novel CEST contrast maps at 9.4 T.ResultsAt a saturation power of B1 = 0.5 μT most selective CEST effects could be obtained in the human brain with high inter-scan reproducibility. While contrast behavior of previously measured signals at lower field, namely amide-, guanidyl- and NOE-CEST effects, could be reproduced, novel signals at 2.7 ppm, and −1.6 ppm could be verified in healthy subjects and in a brain tumor patient for the first time.ConclusionHigh spectral resolution chemical exchange saturation transfer at 9.4 T allows deeper insights into the Z-spectrum structure of the human brain, and provides many different contrasts showing different correlations in healthy tissue and in tumor-affected areas of the brain, generating hypotheses for future investigations of in-vivo-CEST at UHF.



https://ift.tt/2yi71Xd

Individual differences in aesthetic engagement are reflected in resting-state fMRI connectivity: Implications for stress resilience

Publication date: 1 October 2018
Source:NeuroImage, Volume 179
Author(s): Paula G. Williams, Kimberley T. Johnson, Brian J. Curtis, Jace B. King, Jeffrey S. Anderson
ObjectiveIndividual differences in aesthetic engagement—the propensity to be moved by art, nature, and beauty—are associated with positive health outcomes, as well as stress resilience. The purpose of the current study was to identify potential neural substrate mechanisms underlying individual differences in aesthetic engagement and reported proneness to aesthetic chill.MethodsData from the Human Connectome Project (HCP) 1200 Subjects Release were utilized. Resting-state fMRI connectivity was extracted for 361 regions in the brain including cortical, subcortical and cerebellar regions for each participant, using participant-specific segmentation and parcellation of subcortical gray matter nuclei and a network-based statistics analytical approach. The Aesthetic Interests subcluster of the Openness to Experience scale (NEO-Five Factor Inventory; NEO-FFI) was used to characterize individual differences in aesthetic engagement and chill.ResultsParticipants reporting higher aesthetic engagement, particularly proneness to aesthetic chill responses, exhibited significantly higher connectivity between the default network and sensory and motor cortices, higher connectivity between the ventral default and salience networks, and decreased connectivity between the cerebellum and somatomotor cortex.ConclusionsCurrent findings suggest that greater integration of the default mode network, involving processing of internal narrative, with neural representations of sensory perception and salience detection may be a mechanism underlying individual differences in aesthetic engagement. Thus, these individual differences may reflect general integration of environmental perception with internal emotional experience, which in turn may facilitate comfort with novelty, self-regulation, and positive adaptation to potentially stressful experiences.



https://ift.tt/2lfdIzZ

Whole head quantitative susceptibility mapping using a least-norm direct dipole inversion method

Publication date: 1 October 2018
Source:NeuroImage, Volume 179
Author(s): Hongfu Sun, Yuhan Ma, M. Ethan MacDonald, G. Bruce Pike
A new dipole field inversion method for whole head quantitative susceptibility mapping (QSM) is proposed. Instead of performing background field removal and local field inversion sequentially, the proposed method performs dipole field inversion directly on the total field map in a single step. To aid this under-determined and ill-posed inversion process and obtain robust QSM images, Tikhonov regularization is implemented to seek the local susceptibility solution with the least-norm (LN) using the L-curve criterion. The proposed LN-QSM does not require brain edge erosion, thereby preserving the cerebral cortex in the final images. This should improve its applicability for QSM-based cortical grey matter measurement, functional imaging and venography of full brain. Furthermore, LN-QSM also enables susceptibility mapping of the entire head without the need for brain extraction, which makes QSM reconstruction more automated and less dependent on intermediate pre-processing methods and their associated parameters. It is shown that the proposed LN-QSM method reduced errors in a numerical phantom simulation, improved accuracy in a gadolinium phantom experiment, and suppressed artefacts in nine subjects, as compared to two-step and other single-step QSM methods. Measurements of deep grey matter and skull susceptibilities from LN-QSM are consistent with established reconstruction methods.



https://ift.tt/2yfPoYh

Magnetodielectric effects in membranes based on magnetorheological bio-suspensions

Publication date: 5 October 2018
Source:Materials & Design, Volume 155
Author(s): I. Bica, E.M. Anitas
Controlled release of bio-active components in systems based on magnetorheological suspensions (MRSs) can be achieved by exploiting the magnetodielectric effects aimed at investigating the time dependence of electrical conductivity in the presence of a magnetic field for similar membranes, and where membranes with stable physical properties in time have been manufactured. Here, magnetorheological bio-suspensions (MRBSs) are prepared using a microfiber cloth soaked with carbonyl iron and various concentrations of honey and turmeric powder. Plane capacitors are manufactured having MRSs as dielectric materials. We build and describe an experimental setup for measuring the electrical resistance and the quality factor of the capacitors in a static magnetic field superimposed on an alternating electric field. The measured quantities are then used to obtain the electrical conductivity and dispersion curves of MRSs-based membranes. The results show that the obtained quantities are sensibly influenced by the electric field frequency, magnetic flux density as well as by the ration between honey and turmeric powder concentrations.

Graphical abstract

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Design and mechanical evaluation of a novel dynamic growing rod to improve the surgical treatment of Early Onset Scoliosis

Publication date: 5 October 2018
Source:Materials & Design, Volume 155
Author(s): Alba Gonzalez Alvarez, Karl D. Dearn, Bernard M. Lawless, Carolina E. Lavecchia, Francesco Vommaro, Konstantinos Martikos, Tiziana Greggi, Duncan E.T. Shepherd
This paper describes the development of a dynamic implant designed to correct three dimensional spinal deformities in children with Early Onset Scoliosis (EOS). The device is a distraction-based implant that provides two innovative features: (1) a dynamic-viscoelastic system, which gives some flexibility to the implant, to avoid potential device fractures; and (2) a lengthening mechanism that allows minimally invasive elongation surgery to reduce infection. The novel device was designed and evaluated with finite element analysis. Five working prototypes were produced and mechanically tested according to a modified version of the ASTM F1717 Standard. Results demonstrated that the maximum load achieving run-out at 5 million cycles was 180 N. One prototype withstood almost two tests in a row (9 million cycles) with the peak load of 180 N and showed no sign of failure. Three tests performed with higher loads (190 and 200 N) did not achieve full runout due to pedicle screw fracture with only one device fracture along the weld. These results demonstrated an improved fatigue performance in comparison with data from the commercially available VEPTR I device (Depuy Synthes Spine, Raynham, USA). Therefore, the novel device proposed has the clinical potential to improve the surgical treatment of EOS.

Graphical abstract

https://ift.tt/2teh9un

Resolution and evaluation of 3-chlorophenyl-3-hydroxypropionylhydroxamic acid as antivirulence agent with excellent eradication efficacy in Helicobacter pylori infected mice

Publication date: 30 August 2018
Source:European Journal of Pharmaceutical Sciences, Volume 121
Author(s): Qi Liu, Wei-Wei Ni, Zhen Li, Cai-Fu Bai, Dan-Dan Tan, Chang-Jun Pu, Dong Zhou, Qing-Peng Tian, Ni Luo, Kai-Li Tan, Le Dai, Yuan Yan, Yong Pei, Xian-Hui Li, Zhu-Ping Xiao, Hai-Liang Zhu
The continuing emergence of drug-resistant Helicobacter pylori (HP) drives the ongoing need for the development of new and effective anti-HP drugs. Urease inhibitor has now gained strong interest as an alternative approach for HP infections. 3-Chlorophenyl-3-hydroxypropionylhydroxamic acid (CPH), a novel urease inhibitor identified in our group, shows impressive potency, which was optically separated for a further exploration. Here, we report in vitro/in vivo pharmacological evaluation of (±)-CPHs and the enantiomers. The raceme and the individual enantiomers significantly suppress gastritis at 32 mg/kg b.i.d dose with lower toxicity to mammalian cells (with CC50s ≥ 3.16 mM) and mice (LD50s ≥ 2338 mg/kg) than the clinically used agent acetohydroxamic acid. Furthermore, a significant increase of eradication of HP is observed for the combination of (±)-CPHs or the enantiomers with an antimicrobial. These studies revealed that CPH is a promising candidate for an alternative treatment of HP-dependent conditions by targeting virulence factor urease, and CPH may be used as a raceme.

Graphical abstract

https://ift.tt/2te9ITZ