Nanomechanics and ultrastructure of the internal mammary artery adventitia in patients with low and high pulse wave velocity

Publication date: Available online 21 April 2018
Source:Acta Biomaterialia
Author(s): Zhuo Chang, Paolo Paoletti, Steve D. Barrett, Ya Hua Chim, Eva Caamaño-Gutiérrez, Maria Lyck Hansen, Hans Christian Beck, Lars Melholt Rasmussen, Riaz Akhtar
The collagen-rich adventitia is the outermost arterial layer and plays an important biomechanical and physiological role in normal vessel function. While there has been a lot of effort to understand the role of the medial layer on arterial biomechanics, the adventitia has received less attention. In this study, we hypothesized that different ultrastructural and nanomechanical properties would be exhibited in the adventitia of the internal mammary artery (IMA) in patients with a low degree of arterial stiffening as compared to those with a high degree of arterial stiffening. Human IMA biopsies were obtained from a cohort of patients with arterial stiffening assessed via carotid-femoral PWV. Patients were grouped as low PWV (8.5±0.7 ms^-1, n=8) and high PWV (13.4±3.0 ms^-1, n=9). Peakforce QNM Atomic force microscopy (AFM) was used to determine the nanomechanical and morphological properties of the IMA. The nano-scale elastic modulus was found to correlate with PWV. We show for the first time that nano-scale alterations in adventitial collagen fibrils in the IMA are evident in patients with high PWV, even though the IMA is not involved in the carotid-femoral pathway. Our approach provides new insight into systemic structure-property changes in the vasculature, and also provides a method of characterizing small biopsy samples to predict the development of arterial stiffening.STATEMENT OF SIGNIFICANCEArterial stiffening occurs as part of the natural aging process and is strongly linked to cardiovascular risk. Although arterial stiffening is routinely measured in vivo, little is known about how localised changes in artery structure and biomechanics contributes to in vivo arterial stiffening. This study focusses on the role of the outermost layer of arteries, the adventitia, in arterial stiffening. The study provides data on nano-scale changes in collagen fibril structure and mechanical properties in the adventitia and shows how it relates to in vivo stiffness measurements in the vascular system. This is the first study to link in vivo arterial stiffening with nanomechanical changes artery biopsy samples. Hence, this approach could be used to develop new diagnostic methods for vascular disease.

Graphical abstract

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Multi-Scale Structural Design and Biomechanics of the Pistol Shrimp Snapper Claw

Publication date: Available online 21 April 2018
Source:Acta Biomaterialia
Author(s): Shahrouz Amini, Maryam Tadayon, J.Q. Isaiah Chua, Ali Miserez
The Arthropoda, the largest phylum of the Animal Kingdom, have successfully evolved to survive various ecological constraints under a wide range of environmental conditions. Central to this survival are the structural designs developed in their exoskeletons and their raptorial appendages for protection and hunting. One such example, the pistol shrimp, is a shallow-water crustacean that is well-known for its aggressive hunting behavior, using its snapper claw to trigger the nucleation of cavitation bubbles that strike targets. In this study, we conducted a multi-scale structural/nanomechanics relationship study of this biotool to analyze its mechanical response to contact stresses. We found that the pistol shrimp snapper claw, which exhibits the capacity to emit a high-velocity water jet during rapid closure actions, is more brittle than other mineralized biotools, with accelerated wear damage under contact stresses. However, due to an angular offset between the dactylus and pollex of the snapper claw, the appendage never engages in any mechanical contact during the snapping action. This feature is in stark contrast to that reported in other fast raptorial appendages of crustaceans, notably the mantis shrimp dactyl club, which is designed to shatter close range targets in contact mode and exhibits a superior resistance to contact damages and wear. These findings suggest that adaptation of hunting appendages goes beyond their macroscopic morphology, and that multi-scale structural design concomitantly adapted to function, with enhanced structural complexification for tools that are subjected to more intense contact stresses.Statement of SignificanceThe evolution success of crustaceans is largely due to the diversification of their mineralized exoskeletons and hunting appendages, which exhibit a large palette of morphometric characteristics that have adapted to meet particular functions. We explored the "snapper claw" of the pistol shrimp, which is used to generate cavitation bubbles and strike prey. Our multi-scale structure-property relationship study reveals that the snapper claw is more brittle than other fast raptorial appendages –such as the stomatopod dactyl club– because it is not directly subjected to direct contact forces during action. This study implies that when higher mechanical stresses are needed to meet the function, the internal structure is built of a more complex architecture that allows to mitigate internal structural damage.

Graphical abstract

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Injectable drug depot engineered to release multiple ophthalmic therapeutic agents with precise time profiles for postoperative treatment following ocular surgery

Publication date: Available online 21 April 2018
Source:Acta Biomaterialia
Author(s): Maziar Mohammadi, Kisha Patel, Seyedeh P. Alaie, Ron B. Shmueli, Cagri G. Besirli, Ronald G. Larson, Jordan J. Green
A multi-drug delivery platform is developed to address current shortcomings of post-operative ocular drug delivery. The sustained biodegradable drug release system is composed of biodegradable polymeric microparticles (MPs) incorporated into a bulk biodegradable hydrogel made from triblock copolymers with poly(ethylene glycol) (PEG) center blocks and hydrophobic biodegradable polyester blocks such as poly(lactide-co-glycolide) (PLGA), Poly(lactic acid) (PLA), or Poly(lactide-co-caprolactone) (PLCL) blocks. This system is engineered to flow as a liquid solution at room temperature for facile injection into the eye and then quickly gel as it warms to physiological body temperatures (approximately 37 °C). The hydrogel acts as an ocular depot that can release three different drug molecules at programmed rates and times to provide optimal release of each species. In this manuscript, the hydrogel is configured to release a broad-spectrum antibiotic, a potent corticosteroid, and an ocular hypotensive, three ophthalmic therapeutic agents that are essential for post-operative management after ocular surgery, each drug released at its own timescale. The delivery platform is designed to mimic current topical application of postoperative ocular formulations, releasing the antibiotic for up to a week, and the corticosteroid and the ocular hypotensive agents for at least a month. Hydrophobic blocks, such as PLCL, were utilized to prolong the release duration of the biomolecules. This system also enables customization by being able to vary the initial drug loading to linearly tune the drug dose released, while maintaining a constant drug release profile over time. This minimally invasive biodegradable multi-drug delivery system is capable of replacing a complex ocular treatment regimen with a simple injection. Such a depot system has the potential to increase patient medication compliance and reduce both the immediate and late term complications following ophthalmic surgery.Statement of SignificanceAfter ocular surgery, patients routinely receive multiple medications including antibiotics, steroids and ocular hypotensives to ensure optimal surgical outcomes. The current standard of care for postoperative treatment after ocular surgery involves using eye drops daily, which has limited effectiveness mainly due to poor patient adherence. To improve patient experience and outcomes, this article presents the first thermoresponsive hydrogel able to release multiple drug molecules for the application of post-operative treatment following ocular surgery. By varying the parameters such as hydrogel type and polymer hydrophobicity, the drug release profile, duration and dosage can finely be tuned. The approach presented in this article can readily be applied to other applications by simply changing the drug loaded in the drug delivery system.

Graphical abstract

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Component effect of stem cell-loaded thermosensitive polypeptide hydrogels on cartilage repair

Publication date: Available online 21 April 2018
Source:Acta Biomaterialia
Author(s): He Liu, Yilong Cheng, Jinjin Chen, Fei Chang, Jincheng Wang, Jianxun Ding, Xuesi Chen
Biophysical properties of the desired biomimetic scaffolds, such as porosity and elasticity, have been proven associated with the efficacy of cartilage regeneration. In this work, the copolymers of poly(L-alanine)-block-poly(ethylene glycol)-block-poly(L-alanine) (PA-PEG-PA) and poly(L-alanine-co-L-phenylalanine)-block-poly(ethylene glycol)-block-poly(L-alanine-co-L-phenylalanine) (PAF-PEG-PAF) with different ratios of alanine to phenylalanine were synthesized. The introduction of a hydrophobic amino acid, phenylalanine, into polyalanine-based thermosensitive hydrogel leaded to the enhanced gelation behaviors and upregulated mechanical properties. Moreover, the increase of phenylalanine content resulted in the enlarged pore size and enhanced mechanical strength of PAF-PEG-PAF thermogel, followed by the regeneration of hyaline-like cartilage with reduced fibrous tissue formation. The findings indicated the great potential of thermosensitive polypeptide hydrogels in cartilage tissue engineering.Statement of SignificanceArticular cartilage defect has limited self-repair ability due to the lack of blood supply and innervation, which may lead to knee osteoarthritis afterwards. Injectable hydrogels are demonstrated possessing outstanding properties as biomimetic scaffolds in cartilage tissue engineering, while the effect of biophysical properties on the efficacy of cartilage regeneration has not been revealed. Herein, the poly(ethylene glycol)−polypeptide triblock copolymers with different ratios of alanine to phenylalanine were synthesized. The sol-to-gel transition temperature and the critical gelling concentration decreased as the increased amount of phenylalanine units, resulting in the enlarged pore size and enhanced mechanical strength. These features lead to better regeneration of hyaline-like cartilage with reduced fibrous tissue formation, indicating great potential of thermosensitive polypeptide hydrogels for efficient cartilage repair.

Graphical abstract

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Decoration of RGD-mimetic Porous Scaffolds with Engineered and Devitalized Extracellular Matrix for Adipose Tissue Regeneration

Publication date: Available online 21 April 2018
Source:Acta Biomaterialia
Author(s): Eleonora Rossi, Julien Guerrero, Paola Aprile, Alessandro Tocchio, Elisabeth A Kappos, Cristina Lenardi, Ivan Martin, Arnaud Scherberich
Fat grafting is emerging as a promising alternative to silicon implants in breast reconstruction surgery. Unfortunately, this approach does not provide a proper mechanical support and is affected by drawbacks such as tissue resorption and donor site morbidity. Synthetic scaffolds can offer a valuable alternative to address these challenges, but poorly recapitulate the biochemical stimuli needed for tissue regeneration. Here, we aim at combining the positive features of a structural, synthetic polymer to an engineered, devitalized extracellular matrix (ECM) to generate a hybrid construct that can provide a mix of structural and biological stimuli needed for adipose tissue regeneration. A RGD-mimetic synthetic scaffold OPAAF, designed for soft tissue engineering, was decorated with ECM deposited by human adipose stromal cells (hASCs). The adipoinductive potential of the hybrid ECM-OPAAF construct was validated in vitro, by culture with hASC in a perfusion bioreactor system, and in vivo, by subcutaneous implantation in nude mouse. Our findings demonstrate that the hybrid ECM-OPAAF provides proper mechanical support and adipoinductive stimuli, with potential applicability as off-the-shelf material for adipose tissue reconstruction.Statement of significanceIn this study we combined the functionalities of a synthetic polymer with those of an engineered and subsequently devitalized extracellular matrix (ECM) to generate a hybrid material for adipose tissue regeneration. The developed hybrid ECM-OPAAF was demonstrated to regulate human adipose stromal cells adipogenic commitment in vitro and adipose tissue infiltration in vivo. Our findings demonstrate that the hybrid ECM-OPAAF provide proper mechanical support and adipoinductive stimuli and represents a promising off-the-shelf material for adipose tissue reconstruction.We believe that our approach could offer an alternative strategy for adipose tissue reconstruction incase of mastectomy or congenital abnormalities, overcoming the current limitations of autologous fat based strategies such as volume resorption and donor site morbidity.

Graphical abstract

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Using a gradient boosting model to improve the performance of low-cost aerosol monitors in a dense, heterogeneous urban environment

Publication date: July 2018
Source:Atmospheric Environment, Volume 184
Author(s): Nicholas E. Johnson, Bartosz Bonczak, Constantine E. Kontokosta
The increased availability and improved quality of new sensing technologies have catalyzed a growing body of research to evaluate and leverage these tools in order to quantify and describe urban environments. Air quality, in particular, has received greater attention because of the well-established links to serious respiratory illnesses and the unprecedented levels of air pollution in developed and developing countries and cities around the world. Though numerous laboratory and field evaluation studies have begun to explore the use and potential of low-cost air quality monitoring devices, the performance and stability of these tools has not been adequately evaluated in complex urban environments, and further research is needed. In this study, we present the design of a low-cost air quality monitoring platform based on the Shinyei PPD42 aerosol monitor and examine the suitability of the sensor for deployment in a dense heterogeneous urban environment. We assess the sensor's performance during a field calibration campaign from February 7th to March 25th 2017 with a reference instrument in New York City, and present a novel calibration approach using a machine learning method that incorporates publicly available meteorological data in order to improve overall sensor performance. We find that while the PPD42 performs well in relation to the reference instrument using linear regression (R² = 0.36–0.51), a gradient boosting regression tree model can significantly improve device calibration (R² = 0.68–0.76). We discuss the sensor's performance and reliability when deployed in a dense, heterogeneous urban environment during a period of significant variation in weather conditions, and important considerations when using machine learning techniques to improve the performance of low-cost air quality monitors.

Graphical abstract

https://ift.tt/2HiGOYF

Secondary organic aerosol and ozone formation from photo-oxidation of unburned diesel fuel in a surrogate atmospheric environment

Publication date: July 2018
Source:Atmospheric Environment, Volume 184
Author(s): Weihua Li, David R. Cocker
Diesel fuel is a complex mixture of intermediate volatility organic compounds (IVOCs). Previous studies focused on secondary organic aerosol (SOA) and ozone formation from photo-oxidation of organic vapor from diesel exhaust and their components such as aromatics and heavy alkanes. However, there are few studies on atmospheric behavior of unburnt diesel. Therefore, in this study, ten unburnt #2 commercial diesel samples and one FACE9A research diesel fuel were photo-oxidized in the University of California Riverside, College of Engineering-Center for Environmental Research & Technology dual environmental chambers to investigate their SOA and ozone production potential. Photochemical aging rapidly produced significant SOA (yield ∼20.3–37.7%) in the presence of a surrogate reactive organic gas (ROG) mixture used to mimic urban atmospheric reactivity. SOA yields were consistent with n-Heptadecane yields under similar conditions. Doubling NOx concentrations within relevant urban concentration levels enhanced SOA formation by 33% and ozone formation by 48%. SOA formation in this study was approximately fourteen times higher than previously reported for very high NOx conditions. An SOA experiment designed to mimic the previous work achieved similar yields to the earlier work. SOA formed under urban relevant NOx concentrations were consistent with semi-volatile-oxygenated organic aerosol (SV-OOA) and underwent little further chemical processing once produced.



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Emission characteristics of NOx, CO, NH3 and VOCs from gas-fired industrial boilers based on field measurements in Beijing city, China

Publication date: July 2018
Source:Atmospheric Environment, Volume 184
Author(s): Tao Yue, Xiang Gao, Jiajia Gao, Yali Tong, Kun Wang, Penglai Zuo, Xiaoxi Zhang, Li Tong, Chenlong Wang, Yifeng Xue
In the past decade, due to the management policies and coal combustion controls in Beijing, the consumption of natural gas has increased gradually. Nevertheless, the research on the emission characteristics of gaseous pollutants emitted from gas-fired industrial boilers, especially considering the influence of low nitrogen (low-NOx) retrofit policy of gas boilers, is scarcely. In this study, based on literature and field investigations, onsite measurements of NOx, CO, NH3 and VOCs (Volatile Organic Compounds) emissions from gas-fired industrial boilers as well as the key factors that affected the emission of gaseous pollutants were discussed. Category-specific emission factors (EFs) of NOx, CO, NH3 and VOCs were obtained from the field measurements of 1107 "low-NOx" retrofitted and unabated gas-fired industrial boilers. Our results showed that operating load and control measures were the two key factors affecting the formation of gaseous pollutants. The EFs of NOx (EFNOx) and CO (EFCO) of atmospheric combustion boilers (ACBs) were much higher than the EFs of chamber combustion boilers (CCBs). The total emissions of NOx, CO, NH3 and VOCs from gas-fired industrial boilers in Beijing in the year of 2015 were estimated at 10489.6 t, 3272.8 t, 196.4 t and 235.4 t, respectively. Alkanes, BTEX, oxygenated VOCs and non-reactive organic matter were the four main chemical components of VOCs. As for the spatial distributions, the emissions of NOx, CO, NH3 and VOCs from gas-fired industrial boilers in Beijing were predominantly concentrated in central six urban districts. In the future, more detailed investigation and field tests for all kinds of gas-fired industrial boilers are still greatly needed to achieve more reliable estimations of atmospheric pollutants from gas-fired industrial boilers.



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Long-term systematic profiling of dust aerosol optical properties using the EOLE NTUA lidar system over Athens, Greece (2000–2016)

Publication date: June 2018
Source:Atmospheric Environment, Volume 183
Author(s): O. Soupiona, A. Papayannis, P. Kokkalis, M. Mylonaki, G. Tsaknakis, A. Argyrouli, S. Vratolis
We present a comprehensive analysis of the seasonal variability of the vertical profiles of the optical and geometrical properties of Saharan dust aerosols, observed in the height region between 1000 and 6000 m, over the city of Athens, Greece, from February 2000 to December 2016. These observations were performed by a multi-wavelength (355-387-532-1064 nm) Raman lidar system under cloud-free conditions. The statistical analysis (using aerosol monthly mean values) is based on nighttime vertical Raman measurements of range-resolved aerosol optical properties (backscatter and extinction coefficients, lidar ratio, Ångström exponent) at 355 nm (57 dust events during more than 80 measurement hours). We found that the number of dust events was highest in spring, summer, and early autumn periods and that during spring the dust layers were moved at higher altitudes (∼4500 m) than in other seasons. The number of the forecasted dusty days (on monthly basis) by the BSC-DREAM8b model compared to those of the performed lidar measurements were found to have a quite strong correlation (R² = 0.81), with a maximum occurrence predicted for the spring season. In the worst case scenario, at least 50% of the model-forecasted dust events can be observed by lidar under cloudless skies over Athens. For the sampled dust plumes we found mean lidar ratios of 52 ± 13 sr at 355 nm in the height range 2000–4000 m a.s.l. Moreover, the dust layers had a mean thickness of 2497 ± 1026 m and a center of mass of 2699 ± 1017 m.An analysis performed regarding the air mass back-trajectories arriving over Athens revealed two main clusters: one pathway from south-west to north-east, with dust emission areas in Tunisia, Algeria and Libya and a second one from south, across the Mediterranean Sea with emission areas over Libya and the remaining part of Algeria and Tunisia. This clustering enabled us to differentiate between the aerosol optical properties between the two clusters, based on their residence time over the Saharan region, the European continent and the Mediterranean Sea. We finally concluded that even if the dust source regions are about the same, the aging and mixing processes of these air masses, passing over different areas, might have an impact on the aerosol optical properties.

Graphical abstract

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Variability in impact of air pollution on subjective well-being

Publication date: June 2018
Source:Atmospheric Environment, Volume 183
Author(s): Guodong Du, Kong Joo Shin, Shunsuke Managi
This paper examines the impact of variability in impact of air pollution on life satisfaction (LS). Previous studies have shown robust negative impact of air pollution on subjective well-being (SWB). However, empirical studies that consider variability in air pollution effects through comparative city study are limited. This study provides comparative evaluation of two major Chinese cities: Beijing and Shanghai. We apply a geo-statistical spatial interpolation technique on pollution data from monitoring sites to estimate the Sulfur Dioxide (SO2), Nitrogen Dioxide (NO2), coarse particles with a diameter between 2.5 and 10 μm (PM10) and fine particles with a diameter of 2.5 μm or less (PM2.5) pollution exposure of respondents of a survey conducted in 2016. The results show that all pollutants have robust negative impacts on LS for Beijing residents, whereas only SO2 and NO2 have significant negative impacts on LS for Shanghai residents; Per unit impact of SO2 is greater in Shanghai, and that of NO2 is greater in Beijing. Beijing and Shanghai residents have almost same monetary valuation for SO2 reduction but Beijing residents place approximately 1.5 times valuation on NO2 reduction compared to Shanghai residents. Moreover, the LS of Beijing residents is sensitive to temporal changes in the pollution level, whereas Shanghai residents are unaffected by such changes.



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Meat allergy and allergens

Publication date: Available online 21 April 2018
Source:Molecular Immunology
Author(s): Jeffrey M. Wilson, Thomas A.E. Platts-Mills
IgE-mediated hypersensitivity to ingested animal products, including both mammalian and avian sources, is increasingly appreciated as an important form of food allergy. Traditionally described largely in children, it is now clear that allergy to meat (and animal viscera) impacts both children and adults and represents a heterogeneous group of allergic disorders with multiple distinct syndromes. The recognition of entities such as pork-cat syndrome and delayed anaphylaxis to red meat, i.e- the α-Gal syndrome, have shed light on fundamental, and in some cases newly appreciated, features of allergic disease. These include insights into routes of exposure and mechanisms of sensitization, as well as the realization that IgE-mediated reactions can be delayed by several hours. Here we review mammalian and avian meat allergy with an emphasis on the molecular allergens and pathways that contribute to disease, as well as the role of in vitro IgE testing in diagnosis and management.



https://ift.tt/2qPrKvo

Meat allergy and allergens

Publication date: Available online 21 April 2018
Source:Molecular Immunology
Author(s): Jeffrey M. Wilson, Thomas A.E. Platts-Mills
IgE-mediated hypersensitivity to ingested animal products, including both mammalian and avian sources, is increasingly appreciated as an important form of food allergy. Traditionally described largely in children, it is now clear that allergy to meat (and animal viscera) impacts both children and adults and represents a heterogeneous group of allergic disorders with multiple distinct syndromes. The recognition of entities such as pork-cat syndrome and delayed anaphylaxis to red meat, i.e- the α-Gal syndrome, have shed light on fundamental, and in some cases newly appreciated, features of allergic disease. These include insights into routes of exposure and mechanisms of sensitization, as well as the realization that IgE-mediated reactions can be delayed by several hours. Here we review mammalian and avian meat allergy with an emphasis on the molecular allergens and pathways that contribute to disease, as well as the role of in vitro IgE testing in diagnosis and management.



https://ift.tt/2qPrKvo

Clinical Thyroidology®for the Public – Highlighted Article

From Clinical Thyroidology^® for the Public:  A patient survey of hypothyroid individuals demonstrates dissatisfaction with treatment and their managing physicians. Read More…

We welcome your feedback and suggestions. Let us know what you want to see in this publication.

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https://ift.tt/2qQ3MiS

Clinical Thyroidology®for the Public – Highlighted Article

From Clinical Thyroidology^® for the Public:  A patient survey of hypothyroid individuals demonstrates dissatisfaction with treatment and their managing physicians. Read More…

We welcome your feedback and suggestions. Let us know what you want to see in this publication.

Feedback & Suggestions

The post Clinical Thyroidology^®for the Public – Highlighted Article appeared first on American Thyroid Association.

https://ift.tt/2qQ3MiS

Seasonal and downstream alterations of dissolved organic matter and dissolved inorganic ions in a human-impacted mountainous tributary of the Yellow River, China

Abstract

Human activities impose important disturbances on both organic and inorganic chemistry in fluvial systems. In this study, we investigated the intra-annual and downstream variations of dissolved organic carbon (DOC), dissolved organic matter (DOM) excitation-emission matrix fluorescence (EEM) with parallel factor analysis (PARAFAC), major ions, and dissolved inorganic nitrogen (DIN) species in a mountainous tributary of the Yellow River, China. Both DOM quantity and quality, as represented by DOC and DOM fluorescence respectively, changed spatially and seasonally in the studied region. Fluorescence intensity of tryptophan-like components (C3) were found much higher at the populated downstream regions than in the undisturbed forested upstream regions. Seasonally, stronger fluorescence intensity of protein-like components (C3 and C4) was observed in the low-flow period (December) and in the medium-flow period (March) than in the high-flow period (May), particularly for the downstream reaches, reflecting the dominant impacts of wastewater pollution in the downstream regions. In contrast to the protein-like fluorescence, humic-like fluorescence components C1 and C2 exhibited distinctly higher intensity in the high-flow period with smaller spatial variation indicating strong flushing effect of increasing water discharge on terrestrial-sourced humic-like materials in the high-flow period. Pollution-affected dissolved inorganic ions, particularly Na⁺, Cl⁻, and NH₄⁺-N, showed similar spatial and seasonal variations with protein-like fluorescence of DOM. The significant positive correlations between protein-like fluorescence of DOM and pollution-affected ions, particularly Na⁺, Cl⁻, and NH₄⁺-N, suggested that there were similar pollution sources and transportation pathways of both inorganic and organic pollutants in the region. The combination of DOM fluorescence properties and inorganic ions could provide an important reference for the pollution source characterization and river basin management.

https://ift.tt/2qPo9g0

Vitamin Status and Mineralized Tissue Development

Abstract

Purpose of Review

The physiological control of mineralized tissue development is mediated by two processes: mineralization, such as bone formation due to osteoblast activity, and mineralized tissue destruction by osteoclast bone resorption. In this system, nutritional status, including vitamin intake, influences each regulatory processes, although definite responding mechanisms in target cells vary according to each compound.

Recent Findings

In contrast with water-soluble vitamins that constant supply is required, fat-soluble vitamins such as vitamin D and K are stored in the liver and fat tissue for long time. They are metabolized into congeneric compounds with various activities to participate in the local mineralization process in the body.

Summary

During physiological or non-physiological mineralization, the local actions of vitamin D and K are regulated by nutrient factor derived from dietary supply, and influenced by systemic calcium metabolism and homeostasis.

https://ift.tt/2F6Ye8N

Air, water and soil: Which alternatives? Alternative models in environmental toxicology.

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Air, water and soil: Which alternatives? Alternative models in environmental toxicology.

ALTEX. 2018;35(2):254-256

Authors: Sambuy Y, Alloisio S, Bertanza G, Ferretti D, Letasiova S, Mazzoleni G, Pedrazzani R, Caloni F

PMID: 29677698 [PubMed - in process]

https://ift.tt/2JectLr

Giving meaning to alternative methods to animal testing.

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Giving meaning to alternative methods to animal testing.

ALTEX. 2018;35(2):256-257

Authors: Scanarotti C, Rovida C, Penco S, Vernazza S, Tirendi S, Baldelli I, Ciliberti R, Bassi AM

PMID: 29677697 [PubMed - in process]

https://ift.tt/2qQ18KI

First National Congress on Alternatives to Animal Testing and post-congress workshops in India.

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First National Congress on Alternatives to Animal Testing and post-congress workshops in India.

ALTEX. 2018;35(2):258-260

Authors: Akbarsha MA, Mascarenhas B, Pellevoisin C

PMID: 29677696 [PubMed - in process]

https://ift.tt/2HltPWr

Inauguration of the Centro 3R for the promotion of 3Rs principles in teaching and research.

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Inauguration of the Centro 3R for the promotion of 3Rs principles in teaching and research.

ALTEX. 2018;35(2):260-261

Authors: Ahluwalia A, Bassi AM, Milazzo P

PMID: 29677695 [PubMed - in process]

https://ift.tt/2qPovEe

3S - Systematic, systemic, and systems biology and toxicology.

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3S - Systematic, systemic, and systems biology and toxicology.

ALTEX. 2018;35(2):139-162

Authors: Smirnova L, Kleinstreuer N, Corvi R, Levchenko A, Fitzpatrick SC, Hartung T

Abstract
A biological system is more than the sum of its parts - it accomplishes many functions via synergy. Deconstructing the system down to the molecular mechanism level necessitates the complement of reconstructing functions on all levels, i.e., in our conceptualization of biology and its perturbations, our experimental models and computer modelling. Toxicology contains the somewhat arbitrary subclass "systemic toxicities"; however, there is no relevant toxic insult or general disease that is not systemic. At least inflammation and repair are involved that require coordinated signaling mechanisms across the organism. However, the more body components involved, the greater the challenge to reca-pitulate such toxicities using non-animal models. Here, the shortcomings of current systemic testing and the development of alternative approaches are summarized. We argue that we need a systematic approach to integrating existing knowledge as exemplified by systematic reviews and other evidence-based approaches. Such knowledge can guide us in modelling these systems using bioengineering and virtual computer models, i.e., via systems biology or systems toxicology approaches. Experimental multi-organ-on-chip and microphysiological systems (MPS) provide a more physiological view of the organism, facilitating more comprehensive coverage of systemic toxicities, i.e., the perturbation on organism level, without using substitute organisms (animals). The next challenge is to establish disease models, i.e., micropathophysiological systems (MPPS), to expand their utility to encompass biomedicine. Combining computational and experimental systems approaches and the chal-lenges of validating them are discussed. The suggested 3S approach promises to leverage 21st century technology and systematic thinking to achieve a paradigm change in studying systemic effects.

PMID: 29677694 [PubMed - in process]

https://ift.tt/2Jeckrn

A Compound Mutation (c.953C

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A Compound Mutation (c.953C<G and c.49G<A) Aggravates Functional Impairments of C1-INH in Hep G2 Cells.

Allergy Asthma Immunol Res. 2018 May;10(3):285-286

Authors: Xu YY, Zhi YX

PMID: 29676077 [PubMed]

https://ift.tt/2vyKFzu

The Relevance of Nasal Cytology in the Workup of House Dust Mite-Induced Allergic Rhinitis.

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The Relevance of Nasal Cytology in the Workup of House Dust Mite-Induced Allergic Rhinitis.

Allergy Asthma Immunol Res. 2018 May;10(3):283-284

Authors: Gelardi M, Puccinelli P, Incorvaia C, Passalacqua G, Ciprandi G, Italian Cometa Study Group

PMID: 29676076 [PubMed]

https://ift.tt/2HIHEle

Chamber and Field Studies demonstrate Differential Amb a 1 Contents in Common Ragweed Depending on CO₂ Levels.

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Chamber and Field Studies demonstrate Differential Amb a 1 Contents in Common Ragweed Depending on CO₂ Levels.

Allergy Asthma Immunol Res. 2018 May;10(3):278-282

Authors: Choi YJ, Oh HR, Oh JW, Kim KR, Kim MJ, Kim BJ, Baek WG

Abstract
Although atmospheric carbon dioxide (CO₂) has no apparent direct effect on human health, it does have direct effects on plants. The present study evaluated the influence of increased CO₂ levels on the concentration of allergens from common ragweed pollen by setting up a chamber study to model future air conditions and a field study to evaluate current air conditions. For the chamber study, we established 20 ragweed plants in an open-top chamber under different CO₂ levels (380-400, 500-520, 600-620, and 1,000-1,100 parts per million [ppm]). For the field study, we established ragweed plants in rural (Pocheon, Gyeonggi-do; mean CO₂ 320±54.8 ppm) and urban (Gangnam, Seoul; mean CO₂ 440±78.5 ppm) locations. Seeds of the common ragweed (Ambrosia artemisiifolia) were obtained from Daejin University. The Amb a 1 protein content of pollen extracts was quantified using a double sandwich enzyme-linked immunosorbent assay. In our chamber study, the median concentration of Amb a 1 in pollen increased with increasing in CO₂ concentration (1.88 ng/μg in 380-400 ppm CO₂; 3.14 ng/μg in 500-520 ppm CO₂; 4.44 ng/μg in 600-620 ppm CO₂; and 5.36 ng/μg in 1,000-1,100 ppm CO₂). In our field study, we found no significantly different concentration of Amb a 1 between the pollen extracts at the Pocheon (mean±standard deviation, 1.63±0.3 ng/μg pollen in 320±54.8 ppm CO₂) and the Gangnam (2.04±0.7 ng/μg pollen in CO₂ in 440±78.5 ppm CO₂) locations, although the concentration of Amb a 1 was increased in the Gangnam than in the Pocheon locations. Our results suggest that future increases in CO₂ levels to more than 600 ppm will significantly elevate the Amb a 1 content in common ragweeds, although the current different CO₂ levels do not cause differences in the Amb a 1 content of ragweed pollen.

PMID: 29676075 [PubMed]

https://ift.tt/2vBf5RC

Immune Characterization of Bone Marrow-Derived Models of Mucosal and Connective Tissue Mast Cells.

Related Articles

Immune Characterization of Bone Marrow-Derived Models of Mucosal and Connective Tissue Mast Cells.

Allergy Asthma Immunol Res. 2018 May;10(3):268-277

Authors: Benedé S, Cody E, Agashe C, Berin MC

Abstract
PURPOSE: It is well appreciated that mast cells (MCs) demonstrate tissue-specific imprinting, with different biochemical and functional properties between connective tissue MCs (CTMCs) and mucosal MCs (MMCs). Although in vitro systems have been developed to model these different subsets, there has been limited investigation into the functional characteristics of the 2 major MC subsets. Here, we report the immunologic characterization of 2 MCs subsets developed in vitro from bone marrow progenitors modeling MMCs and CTMCs.
METHODS: We grew bone marrow for 4 weeks in the presence of transforming growth factor (TGF)-β, interleukin (IL)-9, IL-3, and stem cell factor (SCF) to generate MMCs, and IL-4, IL-3, and SCF to generate CTMCs.
RESULTS: CTMCs and MMCs differed in growth rate and protease content, but their immune characteristics were remarkably similar. Both subsets responded to immunoglobulin E (IgE)-mediated activation with signaling, degranulation, and inflammatory cytokine release, although differences between subsets were noted in IL-10. CTMCs and MMCs showed a similar toll-like receptor (TLR) expression profile, dominated by expression of TLR4, TLR6, or both subsets were responsive to lipopolysaccharide (LPS), but not poly(I:C). CTMCs and MMCs express receptors for IL-33 and thymic stromal lymphopoietin (TSLP), and respond to these cytokines alone or with modified activation in response to IgE cross-linking.
CONCLUSIONS: The results of this paper show the immunologic characterization of bone marrow-derived MMCs and CTMCs, providing useful protocols for in vitro modeling of MC subsets.

PMID: 29676074 [PubMed]

https://ift.tt/2HBBNxZ

Differences in Genetic Variations Between Treatable and Recalcitrant Atopic Dermatitis in Korean.

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Differences in Genetic Variations Between Treatable and Recalcitrant Atopic Dermatitis in Korean.

Allergy Asthma Immunol Res. 2018 May;10(3):244-252

Authors: Jun M, Wang HY, Lee S, Choi E, Lee H, Choi EH

Abstract
PURPOSE: Variations in barrier- or immune response-related genes are closely related to the development of atopic dermatitis (AD). This study was designed to identify genetic variations and clinical features to predict 'recalcitrant AD.'
METHODS: AD patients were classified as treatable and recalcitrant. Treatable AD patients showed satisfactory clinical improvement with basic and topical treatments. Recalcitrant AD patients used systemic immune-suppressants for over 4 weeks as they had not shown clinical improvement with basic and topical treatments. The frequency of gene variations in barrier- (FLG 3321delA, FLG K4022X, KLK7, SPINK 1156, SPINK 1188, SPINK 2475) and immune response- (DEFB1, KDR, IL-5RA, IL-9, and IL-12RB1a, b) related genes were compared between each AD group and the controls.
RESULTS: Of all, 249 treatable AD and 32 recalcitrant AD were identified. Heterozygous mutations (Hetero) in KLK7 was more frequent in recalcitrant AD patients than treatable AD, without statistical significance. Hetero in DEFB1 was more frequent in treatable AD patients. However, no other significant genetic differences between treatable and recalcitrant AD was observed. Instead, higher initial Eczema Area Severity Index (EASI) score, serum immunoglobulin E (IgE) level, allergen specific IgE for house dust mites, and family history of atopic diseases were associated with recalcitrant AD with statistical significance.
CONCLUSIONS: According to our study, no genetic variation to predict recalcitrant AD was identified, suggesting that clinical manifestation, rather than genetic variations of AD patients is more likely to be an important factor in predicting the prognosis of AD. Further large-scale studies on the correlation between genetic variation and recalcitrant AD are needed.

PMID: 29676071 [PubMed]

https://ift.tt/2vBf3Ju

Perceptions of Severe Asthma and Asthma-COPD Overlap Syndrome Among Specialists: A Questionnaire Survey.

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Perceptions of Severe Asthma and Asthma-COPD Overlap Syndrome Among Specialists: A Questionnaire Survey.

Allergy Asthma Immunol Res. 2018 May;10(3):225-235

Authors: Kim SH, Moon JY, Lee JH, Ban GY, Kim S, Kim MA, Kim JH, Kim MH, Park CS, Park SY, Kwon HS, Kwon JW, Jung JW, Kang HR, Park JS, Kim TB, Park HW, Cho YS, Yoo KH, Oh YM, Lee BJ, Jang AS, Cho SH, Park HS, Park CS, Yoon HJ, Severe Asthma Work Group, the Korean Academy of Asthma, Allergy and Clinical Immunology

Abstract
PURPOSE: Severe asthma and asthma-chronic obstructive pulmonary disease (COPD) overlap syndrome (ACOS) are difficult to control and are often associated with poor clinical outcomes. However, much is not understood regarding the diagnosis and treatment of severe asthma and ACOS. To evaluate the current perceptions of severe asthma and COPD among asthma and COPD specialists, we designed an e-mail and internet-based questionnaire survey.
METHODS: Subjects were selected based on clinical specialty from among the members of the Korean Academy of Asthma, Allergy and Clinical Immunology and the Korean Academy of Tuberculosis and Respiratory Diseases. Of 432 subjects who received an e-mail invitation to the survey, 95 subjects, including 58 allergists and 37 pulmonologists, responded and submitted their answers online.
RESULTS: The specialists estimated that the percentage of severe cases among total asthma patients in their practice was 13.9%±11.0%. Asthma aggravation by stepping down treatment was the most common subtype, followed by frequent exacerbation, uncontrolled asthma despite higher treatment steps, and serious exacerbation. ACOS was estimated to account for 20.7% of asthma, 38.0% of severe asthma, and 30.1% of COPD cases. A history of smoking, persistently low forced expiratory volume in 1 second (FEV1), and low FEV1 variation were most frequently classified as the major criteria for the diagnosis of ACOS among asthma patients. Among COPD patients, the highly selected major criteria for ACOS were high FEV1 variation, positive bronchodilator response, a personal history of allergies and positive airway hyperresponsiveness. Allergists and pulmonologists showed different assessments and opinions on asthma phenotyping, percentage, and diagnostic criteria for ACOS.
CONCLUSIONS: Specialists had diverse perceptions and clinical practices regarding severe asthma and ACOS patients. This heterogeneity must be considered in future studies and strategy development for severe asthma and ACOS.

PMID: 29676069 [PubMed]

https://ift.tt/2HzZIxR

TRPV1 Blocking Alleviates Airway Inflammation and Remodeling in a Chronic Asthma Murine Model.

Related Articles

TRPV1 Blocking Alleviates Airway Inflammation and Remodeling in a Chronic Asthma Murine Model.

Allergy Asthma Immunol Res. 2018 May;10(3):216-224

Authors: Choi JY, Lee HY, Hur J, Kim KH, Kang JY, Rhee CK, Lee SY

Abstract
PURPOSE: Asthma is a chronic inflammatory airway disease characterized by airway hyperresponsiveness (AHR), inflammation, and remodeling. There is emerging interest in the involvement of the transient receptor potential vanilloid 1 (TRPV1) channel in the pathophysiology of asthma. This study examined whether TRPV1 antagonism alleviates asthma features in a murine model of chronic asthma.
METHODS: BALB/c mice were sensitized to and challenged by ovalbumin to develop chronic asthma. Capsazepine (TRPV1 antagonist) or TRPV1 small interfering RNA (siRNA) was administered in the treatment group to evaluate the effect of TPV1 antagonism on AHR, airway inflammation, and remodeling.
RESULTS: The mice displayed increased AHR, airway inflammation, and remodeling. Treatment with capsazepine or TRPV1 siRNA reduced AHR to methacholine and airway inflammation. Type 2 T helper (Th2) cytokines (interleukin [IL]-4, IL-5, and IL-13) were reduced and epithelial cell-derived cytokines (thymic stromal lymphopoietin [TSLP], IL-33, and IL-25), which regulate Th2 cytokine-associated inflammation, were also reduced. Airway remodeling characterized by goblet cell hyperplasia, increased α-smooth muscle action, and collagen deposition was also alleviated by both treatments.
CONCLUSIONS: Treatment directed at TRPV1 significantly alleviated AHR, airway inflammation, and remodeling in a chronic asthma murine model. The TRPV1 receptor can be a potential drug target for chronic bronchial asthma.

PMID: 29676068 [PubMed]

https://ift.tt/2vuTMB6

Significance of Skin Barrier Dysfunction in Atopic Dermatitis.

Related Articles

Significance of Skin Barrier Dysfunction in Atopic Dermatitis.

Allergy Asthma Immunol Res. 2018 May;10(3):207-215

Authors: Kim BE, Leung DYM

Abstract
The epidermis contains epithelial cells, immune cells, and microbes which provides a physical and functional barrier to the protection of human skin. It plays critical roles in preventing environmental allergen penetration into the human body and responsing to microbial pathogens. Atopic dermatitis (AD) is the most common, complex chronic inflammatory skin disease. Skin barrier dysfunction is the initial step in the development of AD. Multiple factors, including immune dysregulation, filaggrin mutations, deficiency of antimicrobial peptides, and skin dysbiosis contribute to skin barrier defects. In the initial phase of AD, treatment with moisturizers improves skin barrier function and prevents the development of AD. With the progression of AD, effective topical and systemic therapies are needed to reduce immune pathway activation and general inflammation. Targeted microbiome therapy is also being developed to correct skin dysbiosis associated with AD. Improved identification and characterization of AD phenotypes and endotypes are required to optimize the precision medicine approach to AD.

PMID: 29676067 [PubMed]

https://ift.tt/2HjuPy8

Allergen-Specific Immunotherapies for Food Allergy.

Related Articles

Allergen-Specific Immunotherapies for Food Allergy.

Allergy Asthma Immunol Res. 2018 May;10(3):189-206

Authors: Feuille E, Nowak-Wegrzyn A

Abstract
With rising prevalence of food allergy (FA), allergen-specific immunotherapy (AIT) for FA has become an active area of research in recent years. In AIT, incrementally increasing doses of inciting allergen are given with the goal to increase tolerance, initially through desensitization, which relies on regular exposure to allergen. With prolonged therapy in some subjects, AIT may induce sustained unresponsiveness, in which tolerance is retained after a period of allergen avoidance. Methods of AIT currently under study in humans include oral, sublingual, epicutaneous, and subcutaneous delivery of modified allergenic protein, as well as via DNA-based vaccines encoding allergen with lysosomal-associated membrane protein I. The balance of safety and efficacy varies by type of AIT, as well as by targeted allergen. Age, degree of sensitization, and other comorbidities may affect this balance within an individual patient. More recently, AIT with modified proteins or combined with immunomodulatory therapies has shown promise in making AIT safer and/or more effective. Though methods of AIT are neither currently advised by experts (oral immunotherapy [OIT]) nor widely available, AIT is likely to become a part of recommended management of FA in the coming years. Here, we review and compare methods of AIT currently under study in humans to prepare the practitioner for an exciting new phase in the care of food allergic patients in which improved tolerance to inciting foods will be a real possibility.

PMID: 29676066 [PubMed]

https://ift.tt/2qOaO8P

The Emerging Role of TRPV1 in Airway Inflammation.

Related Articles

The Emerging Role of TRPV1 in Airway Inflammation.

Allergy Asthma Immunol Res. 2018 May;10(3):187-188

Authors: Kim JH

PMID: 29676065 [PubMed]

https://ift.tt/2qPtm7R

Retraction notice to An imprinted Ag@CdS core shell nanoparticle based optical-electrochemical dual probe for trace level recognition of ferritin Biosensors and Bioelectronics Volume 63, 15 January 2015, Pages 301-310

Publication date: 15 July 2018
Source:Biosensors and Bioelectronics, Volume 111
Author(s): Santanu Patra, Ekta Roy, Rashmi Madhuri, Prashant K. Sharma




https://ift.tt/2K0ZTQV

Facile one-pot synthesis of visible light-responsive BiPO4/nitrogen doped graphene hydrogel for fabricating label-free photoelectrochemical tetracycline aptasensor

Publication date: 15 July 2018
Source:Biosensors and Bioelectronics, Volume 111
Author(s): Lan Ge, Henan Li, Xiaojiao Du, Mingyue Zhu, Wei Chen, Tingyan Shi, Nan Hao, Qian Liu, Kun Wang
It is fundamental to develop highly efficient visible light-responsive photoelectrochemical (PEC) performance material for fabricating PEC biosensor. Herein, BiPO4/three-dimensional nitrogen doped graphene hydrogel (3DNGH) nanocomposites were prepared for the first time via a facile one-pot hydrothermal route. In this nanoarchitecture, the BiPO4 nanorods were anchored onto the porous structure of 3DNGH. Compared with pristine BiPO4, the absorption of BiPO4/3DNGH has been extend to visible-light region, and the energy band gap of BiPO4/3DNGH was calculated to be 2.10 eV, which was greatly narrower than that of pristine BiPO4 with a band gap of 3.85 eV. Under visible light irradiation, the photocurrent signal of the as-prepared BiPO4/3DNGH was 847.2-fold, 4.1-fold and 2.3-fold enhanced comparing to pristine BiPO4, BiPO4 functionalized reduced graphene oxide and BiPO4/nitrogen doped graphene. The enhancement of such photocurrent signal was attributed to the introduction of 3DNGH, which was capable to improve the charge transfer rate and also the efficiency of visible-light utilization of BiPO4. Based on the excellent PEC properties of BiPO4/3DNGH, a label-free PEC aptasensor for selectivity and sensitivity detection of tetracycline (Tc) was successfully established by using Tc aptamer as a biorecognition element. Under optimized conditions, the proposed PEC aptasensor exhibited a wide linear in the range from 0.1 nmol L⁻¹ to 1 μmol L⁻¹ as well as a low detection limit of 0.033 nmol L⁻¹ (S/N = 3). The prepared BiPO4/3DNGH nanocomposites would serve as a promising visible light-responsive photoactive material for fabrication of PEC biosensors with high performance.



https://ift.tt/2JdJdo8

Electrochemical biointerfaces based on carbon nanotubes-mesoporous silica hybrid material: Bioelectrocatalysis of hemoglobin and biosensing applications

Publication date: 15 July 2018
Source:Biosensors and Bioelectronics, Volume 111
Author(s): Marcos Eguílaz, Reynaldo Villalonga, Gustavo Rivas
We are reporting a novel biosensing platform based on a hybrid nanomaterial that combines the advantages of Nafion-coated multiwalled carbon nanotubes (MWCNTs) and mesoporous silica MCM41 nanoparticles functionalized with hemoglobin (Hb). MWCNTs-MCM41-Hb hybrid bioconjugate was characterized by scanning electron microscopy (SEM), UV–vis spectroscopy and electrochemical techniques after deposition at glassy carbon electrodes (GCE). The combination of the high surface area, biocompatibility and protein loading capacity of MCM41 nanoparticles and the high surface area and catalytic properties of MWCNTs allowed the direct electron transfer (DET) between Hb and the electrode surface. The electron transfer rate constant (k) and the surface coverage of electroactive Hb (ΓHb) were 5.2 s⁻¹ and 4.7 × 10⁻¹⁰ mol cm⁻², respectively. The GCE modified with the nanostructured architecture (GCE/MWCNTs-MCM41-Hb) was successfully used as a third-generation biosensor for the highly sensitive and selective quantification of nitrite (NO2^-) and trichloroacetic acid (TCA) by taking advantage of the excellent biocatalytic activity of Hb and the efficient direct charge transfer of the heme group.



https://ift.tt/2K0ZSfP

AuNP-RF sensor: An innovative application of RF technology for sensing pathogens electrically in liquids (SPEL) within the food supply chain

Publication date: 15 July 2018
Source:Biosensors and Bioelectronics, Volume 111
Author(s): Leann Lerie Matta, Saranraj Karuppuswami, Premjeet Chahal, Evangelyn C. Alocilja
Rapid detection techniques of pathogenic bacteria in the liquid food supply chain are of significant research interest due to their pivotal role in preventing foodborne outbreaks, and in maintaining high standards of public health and safety. Milk and dairy products are of particular interest due to their widespread consumption across the globe. In this paper, a biosensor for detecting pathogenic bacteria in milk using dextrin-capped gold nanoparticles (d-AuNP) as labels decoded at microwave frequencies is presented. The SPEL (sensing pathogens electrically in liquids) biosensor consists of a 3D printed vial and uses an RF reader and an RFID (radio-frequency identification) compatible Split Ring Resonator (SRR) based tag. The SPEL biosensor is capable of detecting bacteria at 5 log CFU/mL within 75 min, with the possibility of testing multiple concurrent samples. Detection is based on impedance loading of SRR by d-AuNP bound to pathogenic bacteria. Spectrophotometry, along with carbohydrate-functionalized magnetic nanoparticle (MNP) cell capture, is used to verify the sensitivity of the SPEL biosensor with respect to d-AuNP presence. The proof-of-concept device, along with challenges and opportunities for commercialization, are also outlined.

Graphical abstract

https://ift.tt/2F6UhAZ

Electric-field driven assembly of live bacterial cell microarrays for rapid phenotypic assessment and cell viability testing

Publication date: 15 July 2018
Source:Biosensors and Bioelectronics, Volume 111
Author(s): Meenal Goel, Abhishek Verma, Shalini Gupta
Microarray technology to isolate living cells using external fields is a facile way to do phenotypic analysis at the cellular level. We have used alternating current dielectrophoresis (AC-DEP) to drive the assembly of live pathogenic Salmonella typhi (S.typhi) and Escherichia coli (E.coli) bacteria into miniaturized single cell microarrays. The effects of voltage and frequency were optimized to identify the conditions for maximum cell capture which gave an entrapment efficiency of 90% in 60 min. The chip was used for calibration-free estimation of cellular loads in binary mixtures and further applied for rapid and enhanced testing of cell viability in the presence of drug via impedance spectroscopy. Our results using a model antimicrobial sushi peptide showed that the cell viability could be tested down to 5 μg/mL drug concentration under an hour, thus establishing the utility of our system for ultrafast and sensitive detection.

Graphical abstract

https://ift.tt/2K53ayB

Non-enzymatic sensing of glucose using screen-printed electrode modified with novel synthesized CeO2@CuO core shell nanostructure

Publication date: 15 July 2018
Source:Biosensors and Bioelectronics, Volume 111
Author(s): Dayakar T., K. Venkateswara Rao, K. Bikshalu, V. Malapati, Kishor Kumar Sadasivuni
We fabricated a fourth generation glucose biosensor using CeO2@CuO core shell nano structure (CeCCS NSs). A simple leave extract of Ocimum tenuiflorum was used to prepare different wt% of 0.2, 04, 0.6, and 0.8 CuO (shell), above 1 wt% of CeO2 (core). The successful formation was confirmed by various characterization techniques like XRD, Uv–Vis, FTIR, SEM and HR-TEM. In the biosensor, 0.4 wt% of CeCCS NSs has shown efficient properties due to its high surface area. The good conductivity and high catalytic activity towards glucose sensing properties were estimated by screen-printed electrode (SPE). The ampherometric studies of CeCCS/SPE modified electrode have been optimized at potential + 0.4 V, showed a sensitivity of 3319.83 μAm M⁻¹ cm⁻² within detection limit of 0.019 μM. More significantly, modified electrodes performed excellently against anti-interference and anti-poisoned activity in glucose sample and exhibited promising results for the sustainable improvement for non-enzymatic sensing applications.



https://ift.tt/2F7szUO

An interdigitated electrode biosensor platform for rapid HLA-B*15:02 genotyping for prevention of drug hypersensitivity

Publication date: 15 July 2018
Source:Biosensors and Bioelectronics, Volume 111
Author(s): Gita V. Soraya, Jianxiong Chan, Thanh C. Nguyen, Duc H. Huynh, Chathurika D. Abeyrathne, Gursharan Chana, Marian Todaro, Efstratios Skafidas, Patrick Kwan
Prevention of life threatening hypersensitivity reactions to carbamazepine is possible through pre-treatment screening of the associated HLA-B*15:02 risk allele. However, clinical implementation of screening is hindered by the high cost and slow turnaround of conventional HLA typing methods. We have developed an interdigitated electrode (IDE) biosensor platform utilizing loop mediated isothermal amplification (LAMP) that can rapidly detect the HLA-B*15:02 allele. DNA amplification is followed by solid-phase hybridization of LAMP amplicons to a DNA probe immobilized on the IDE sensor surface, resulting in a change in sensor impedance. The testing platform does not require DNA extraction or post-amplification staining, achieving sample-to-answer in 1 h and 20 min. The platform was tested on 27 whole blood samples (14 HLA-B*15:02 positive and 13 negative) with sensitivity of 92.9% and specificity of 84.6% when applying a cutoff of impedance change. Based on these characters the LAMP-IDE platform has potential to be further developed into point-of-care use to help overcome barriers in HLA-B*15:02 screening.



https://ift.tt/2K3M4RW

Cytokines regulating lymphangiogenesis

Miguel Sáinz-Jaspeado | Lena Claesson-Welsh

https://ift.tt/2HQZ24x

Development of next generation hemagglutinin-based broadly protective influenza virus vaccines

Raffael Nachbagauer | Peter Palese

https://ift.tt/2HRoLtX

The relationship between diurnal temperature range and COPD hospital admissions in Changchun, China

Abstract

Diurnal temperature range (DTR) has been suggested to be an adverse health factor especially related to respiratory and cardiovascular diseases. In the current study, we investigated the association between DTR and chronic obstructive pulmonary disease (COPD) hospital admissions during 2009 to 2012 in northeast city of Changchun, China. Based on generalized additive model (GAM), the effects were expressed as relative risk (RR) values of COPD with 95% confidence intervals (CIs) with each 1 °C increase in DTR. And they were significantly increased with an increment of 1 °C in DTR, modified by season, age, and sex. The elderly were more vulnerable, with relative risk values of 1.048 (1.029, 1.066) in cold season and 1.037 (1.021, 1.053) in warm season. Regarding the gender, the DTR effect on females was greater during cold season and the RR value was 1.051 (1.033, 1.069) on the current day (lag 0). The greater estimates for males appeared at lag 7 days, with RR of 1.019 (0.998, 1.040). A season-specific effect was detected that the relative risk values with per 1 °C increase in DTR were greater in cold season than in warm season. These findings support the hypothesis of significant relationship between DTR and COPD in Changchun, one northeast city of China.

https://ift.tt/2HiWHCD

A comparison of blood metal levels in autism spectrum disorder and unaffected children in Shenzhen of China and factors involved in bioaccumulation of metals

Abstract

The present study compared blood plasma metals in children with autism spectrum disorder (ASD) with those in unaffected children in Shenzhen (China). Factors associated with the metal bioaccumulation were further investigated. Thirty-four blood samples of children with ASD were collected in a local hospital (Shenzhen Children's Hospital), while those of 38 unaffected children were from a local large public kindergarten, during March to April in 2016. Metal analysis was carried out by inductively coupled plasma-optical emission spectrometry. The results showed that children with ASD had higher (P < 0.01, 0.05) Pb (ASD 31.9 μg/L, unaffected children 18.6 μg/L), Hg (3.83, and 1.09 μg/L), and Cd (0.70 and 0.26 μg/L) than unaffected children, while essential elements Zn (ASD 4552.0 μg/L, unaffected children 5118.6 μg/L), Se (61.7 and 90.6 μg/L), and Mn (13.5 and 21.4 μg/L) showed an opposite pattern. Moreover, the children exposed to passive smoking had higher (P < 0.05) Cd (passive smoking 1.08 μg/L; non-passive smoking 0.22 μg/L) than those without the exposure. Positive associations were found between levels of Hg or Pb and seafood consumption as well as body mass index (BMI). More future work is needed in order to clarify the association between metal exposure and ASD occurrence in China.

https://ift.tt/2qRlEdb

Meeting report: IUPS and ADInstruments 2017 Teaching Workshop.

Related Articles

Meeting report: IUPS and ADInstruments 2017 Teaching Workshop.

Adv Physiol Educ. 2018 Jun 01;42(2):334-339

Authors: Marcondes FK, Cardozo LT, Luchi KCG, Irfannuddin M, Karatzaferi C, Rocha MJ, Carroll RG

Abstract
Every 4 yr, the International Union of Physiological Sciences (IUPS) Teaching Workshop is held as a traditional satellite event of the IUPS Congress. The 2017 satellite workshop was held August 5-8, 2017 in Búzios, Rio de Janeiro, Brazil. The workshop provided an opportunity for discussion and experiences in physiology teaching for educators at various levels, graduate students, and undergraduate students. This report describes the workshop activities and reports the participants' perceptions of this event. For evaluation of perception, an anonymous questionnaire was sent by e-mail to all participants, addressing nine items: appropriate topics, time of activities, poster session, congress venue, registration fee, attention of the organizing committee before and during the event, social event, and food. Responses were ranked according to a five-point Likert scale. Of the 145 participants, 77 answered the questionnaire. The participants' perception was positive, noting in particular opportunities to share knowledge, space for reflection of teaching practice, contact networks for future, exchanges of experience, and collaborations in research in physiological education.

PMID: 29676607 [PubMed - in process]

https://ift.tt/2K2oAwi

Efficiency in the European agricultural sector: environment and resources

Abstract

This article intends to compute agriculture technical efficiency scores of 27 European countries during the period 2005–2012, using both data envelopment analysis (DEA) and stochastic frontier analysis (SFA) with a generalized cross-entropy (GCE) approach, for comparison purposes. Afterwards, by using the scores as dependent variable, we apply quantile regressions using a set of possible influencing variables within the agricultural sector able to explain technical efficiency scores. Results allow us to conclude that although DEA and SFA are quite distinguishable methodologies, and despite attained results are different in terms of technical efficiency scores, both are able to identify analogously the worst and better countries. They also suggest that it is important to include resources productivity and subsidies in determining technical efficiency due to its positive and significant exerted influence.

https://ift.tt/2vBBHS8

Role of noninvasive imaging of cerebral arterial system in ischemic stroke: Comparison of transcranial color-coded doppler sonography with magnetic resonance angiography

Betty Simon, Sunithi Elizabeth Mani, Shyamkumar Nidugala Keshava, Mathew Alexander, Sanjith Aaron

Journal of Clinical Imaging Science 2018 8(1):19-19

Aim: To determine the accuracy of transcranial color-coded Doppler sonography (TCCS) in the evaluation of cerebral arterial system in patients with ischemic stroke attending a tertiary care hospital in South India. Objectives: (1) To describe the topographical distribution of atherosclerotic lesions in the cerebral circulation in patients presenting with ischemic stroke from the Indian subcontinent and (2) to determine the accuracy of TCCS for detection and quantification of intracranial stenoses in various segments of the intracerebral arterial system in comparison with magnetic resonance angiography (MRA). Materials and Methods: The demographic profile and risk factors of consecutive patients who presented to neurology outpatient department with cerebral ischemia and scheduled for MRA were determined. These patients had undergone neck Doppler, TCCS, and MRA. The agreement between the MRA and TCCS was assessed using kappa statistics. The sensitivity, specificity, and positive and negative predictive values of TCCS as compared to MRA were calculated. Results: Ninety patients were included in the final analysis. Intracranial atherosclerosis was found in 35.6% of cases. The agreement between TCCS and MRA in detecting lesions for the different arterial segments in the intracranial circulation was 0.83 for anterior cerebral artery (ACA), 0.66 for M1 segment of middle cerebral artery (MCA), 0.45 for M2 segment of MCA, 0.86 for terminal internal carotid artery (TICA), 0.46 for posterior cerebral artery (PCA), and 0.81 for vertebral artery (VA). The sensitivity for the detection of hemodynamically significant arterial lesions in different vascular segments was 100%, 70%, 33.3%, 90.9%, 33.3%, and 72.7% for ACA, M1, M2, TICA, PCA, and VA, respectively. Conclusion: Intracranial atherosclerosis was found to be the predominant distribution of cerebral atherosclerosis. TCCS is a safe method for evaluation of proximal basal cerebral arteries in the intracranial circulation with relatively better sensitivity in the anterior circulation.

https://ift.tt/2JfHzCx

Overcoming wound complications in head and neck salvage surgery

Loco-regional treatment failure after radiotherapy with or without chemotherapy and/or prior surgery represents a significant portion of head and neck cancer patients. Due to a wide array of biological interactions, these patients have a significantly increased risk of complications related to wound healing.

https://ift.tt/2K4c7Z9

Dermatology Subspecialty Clinic for Patients with Connective Tissue Disease Impacts Diagnosis and Treatment: A Single-Center, Retrospective Analysis

https://ift.tt/2HEpsJq

Vitamin D Status in Scarring and Non-Scarring Alopecia

https://ift.tt/2vyYCO2

Appropriate Use Criteria in Dermatopathology: Initial Recommendations from the American Society of Dermatopathology

Appropriate use criteria (AUC) combine the best scientific evidence available with expert judgment yielding a statement of the appropriateness for performing a test in specific clinical scenarios. Initial recommendations for the use of selected ancillary studies in dermatopathology are outlined. AUC can impact health care delivery, inform reimbursement policy, and guide physician decision making.

https://ift.tt/2vHnqDF

National Skin Cancer Expenditure Analysis in the United States Medicare Population, 2013

https://ift.tt/2qNKewh

Presynaptic dopaminergic neuroimaging in REM sleep behavior disorder: a systematic review and meta-analysis

The presence of polysomnography-confirmed REM sleep behavior disorder (RBD) is the stronger risk factor for having prodromal Parkinson disease (PD), followed by abnormal presynaptic dopaminergic radionuclide neuroimaging. Aim of the review is to conduct a meta-analysis of literature data regarding presynaptic dopaminergic neuroimaging in RBD.A literature search was conducted, resulting in 16 papers that met the inclusion criteria. Clinical and neuroimaging data were extracted. The studies are heterogeneous, especially for neuroimaging methodology.

https://ift.tt/2HjiIkQ

Effectiveness of nutrient remotion and cell physiology of Amphora sp. cultured in shrimp farm effluents

Abstract

Shrimp farm effluents are one of the principal causes of eutrophication in coastal environments. Integrated processes of bioremediation involving the culturing of purifying organisms have been suggested, but very few studies have focused on microalgae. For that purpose evaluated the growth potential of Amphora sp. in the residual waters of shrimp farm activity fulfilled on the Paraíba State, Brazil. The experiments were performed using Conway medium as the control and wastewaters from shrimp farm at 100% concentrations. Amphora sp. demonstrated good growth in the shrimp farm effluents under test conditions, although less than that observed in the control medium. This diatom was found to removed 73.357 and 72.572% of PO₄⁻ and NO₃⁻, respectively, demonstrating a high mitigation potential for this type of effluent. Comparisons of the physiological responses measured by flow cytometry demonstrated higher cell densities of Amphora sp. in the control medium, but a higher lipid content was observed in Amphora cultured in shrimp farm effluents.

https://ift.tt/2qPn08p

A report of Cylindrospermopsis raciborskii and other cyanobacteria in the water reservoirs of power plants in Ukraine

Abstract

The occurrence of cyanobacteria in freshwaters attracts much attention due to its associated health threats and ecological implications. Yet data on the composition of cyanobacteria taxa and toxigenicity in some regions is still scarce. Here, we explored the occurrence of cyanobacteria and cyanotoxins in three locations in Ukraine (reservoir for Kasperivtsi Hydrothermal Power Plant and outflowing River Seret, and cooling pond of Khmelnytsky Atomic Power Plant) in summer 2017. Cyanobacteria were a dominant fraction at all stations. A number of potent-toxin producers were identified including Cylindrospermopsis raciborskii, Aphanizomenon gracile, Dolichospermum flos-aquae, and Planktothrix agardhii. Screening for the presence of dissolved and particulate content of microcystins (-LR, -YR, and -RR), cylindrospermopsin, and anatoxin-a yielded negative results. The studied waters displayed no toxicity in human platelets in vitro. Further toxicological and ecological studies are necessary to evaluate the potential presence of cyanotoxin producers in Ukraine.

https://ift.tt/2HiFIQT

Fetuin B Links Vitamin D deficiency and Pediatric Obesity: Direct Negative Regulation by Vitamin D

Publication date: Available online 21 April 2018
Source:The Journal of Steroid Biochemistry and Molecular Biology
Author(s): Gillian E. Walker, Antonia Follenzi, Valentina Bruscaggin, Marcello Manfredi, Simonetta Bellone, Emilio Marengo, Luigi Maiuri, Flavia Prodam, Gianni Bona
Vitamin D (VD) deficiency (VDD) correlates to obesity, with VD a recognized mediator of metabolic diseases. From a previous proteomic study identifying adiponectin as a link between VDD and pediatric obesity, herein we analysed another protein (SSP2301) increased with VDD. A focused 2D-electrophoretic analysis identified 4 corresponding plasma proteins, with one predicted to be fetuin B (FETUB). FETUB was studied due to its emerging role in metabolic diseases and cytogenetic location (3q27.3) with adiponectin. Results were confirmed in obese children, where plasma FETUB was higher with VDD. A direct effect by 1α,25-(OH)2D3 on hepatocellular FETUB synthesis was observed, with a time and dose dependent reduction. Further, we demonstrated the VD-receptor (VDR) is key, with FETUB "released" with VDR silencing. Finally, VD supplementation (6weeks) to juvenile mice fed a standard diet, reduced plasma FETUB. Only at 22weeks did liver FETUB correspond to plasma FETUB, highlighting the contribution of other VD-responsive tissues. Overall, FETUB is a key protein linking VDD to pediatric obesity. With an emerging role in metabolic diseases, we demonstrate that VD/VDR directly regulate FETUB.

Graphical abstract

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Impairment of the Gnα11-controlled expression of claudin-1 and MMP-9 and collective migration of human breast cancer MCF-7 cells by DHEAS

Publication date: Available online 21 April 2018
Source:The Journal of Steroid Biochemistry and Molecular Biology
Author(s): Neha Upmanyu, Ahmed Bulldan, Dimitrios Papadopoulos, Raimund Dietze, Viveka Nand Malviya, Georgios Scheiner-Bobis
Although dehydroepiandrosterone sulfate (DHEAS) constitutes the most abundant steroid in humans, in-depth investigations of its effects are rather scarce. We address here DHEAS effects on the estrogen receptor-positive metastatic human breast cancer cell line MCF-7. We focus on DHEAS-mediated signaling that might influence expression of claudin-1 and matrix metalloproteinase-9 (MMP-9), both known to be critical factors for migration and invasiveness of various cancers, including breast cancer cells.Physiological concentrations of DHEAS trigger persistent phosphorylation of Erk1/2 in MCF-7 cells. Exposure of these cells for 24 h to 1 µM DHEAS also leads to a significant reduction of claudin-1 expression that cannot be prevented by high concentrations of the steroid sulfatase inhibitor STX64, indicating that desulfation and further conversion of DHEAS to some other steroid hormone is not required for this action. In addition, exposure of MCF-7 cells to the same concentration of DHEAS completely abolishes MMP-9 expression and considerably impairs cell migratory behavior.Abrogation of Gnα11 expression by siRNA prevents the stimulatory effect of DHEAS on Erk1/2 phosphorylation, consistent with a G-protein-coupled receptor being involved in the DHEAS-induced signaling. Nevertheless, Gnα11 also has direct effects that do not depend on DHEAS; thus, when Gnα11 expression is suppressed, expression of claudin-1 and MMP-9 as well as cell migration are significantly reduced.This is the first report demonstrating direct involvement of DHEAS and Gnα11 in the regulation of claudin-1 and MMP-9 expression and migration of MCF-7 cells.

Graphical abstract

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Phthalates and type 1 diabetes: is there any link?

Abstract

Phthalates are a group of chemical compounds used as plasticizers in the manufacture of plastic materials. They can be present in many commonly used products. There seems to be a relationship between exposure to phthalates and the occurrence of metabolic dysfunctions, such as a decrease in glucose tolerance, oxidative stress, loss of beta cells, and a decrease in insulin synthesis. As beta cells play a key role in the onset of type 1 diabetes mellitus (T1DM), we sought to investigate the relationship between exposure to phthalates and the diagnosis of T1DM in prepubertal children. Design concentrations of phthalate metabolites were compared in the urine of a population of prepubertal children with new-onset diabetes, patients with T1DM diagnosed more than 6 months previously, and healthy control children. Although the concentrations of DBP and DiBP metabolites were statistically identical in the new-onset diabetes, diabetes, and control groups, there was a clear trend for higher levels of DiBP metabolites in the children with new-onset diabetes. In our sample, there was a trend for higher levels of DiBP metabolites in children with new-onset diabetes.

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Spatial distribution of uranium and basic water quality parameter in the capital of Bihar and consequent ingestion dose

Abstract

Investigation of presence of Uranium (U) in groundwater/drinking water is an active are of research due to its chemical and radiological toxicity as well as long-term health effects. The current study had the objective of estimating U as a naturally occurring radioactive element in groundwater samples and assessment of ingestion dose, when groundwater is the source of drinking water. The random sampling method was chosen for the collection of samples based on population density. The estimation of U was done using LED fluorimeter. Statistical tools were applied to analyze the data and its spatial distribution. The U concentrations in three blocks of urban Patna were well below the permissible limits suggested by different health agencies of the world. A correlation test was performed to analyze the association of U with other physiochemical parameters of water samples. It was found that the sulfate, chloride, calcium, hardness, alkalinity, TDS, salinity, and ORP were positively correlated, whereas fluoride, phosphate, magnesium, dissolved oxygen, and pH were negatively correlated with U concentrations. The ingestion dose due to U, occurring in groundwater, was found to vary from 0.2–27.0 μSv y⁻¹ with a mean of 4.2 μSv y⁻¹, which was well below the recommended limit of 0.1 mSv (WHO WHO Chron 38:104–108, 2012).Therefore, the water in this region is fit for drinking purposes.

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Facile synthesis of γ-Fe2O3/BiOI microflowers with enhanced visible light photocatalytic activity

Publication date: 15 July 2018
Source:Materials & Design, Volume 150
Author(s): Jinfen Niu, Ziqi Zhang, Peixuan Dai, Binghua Yao, Xiaojiao Yu, Qian Zhang, Rong Yang
The composite materials of γ-Fe2O3/BiOI are synthesized by sol-gel and microwave hydrothermal method, in which γ-Fe2O3 is the magnetic carrier. The composition and property of the composite catalyst are studied by XRD, TEM, XPS, and UV-vis DRS methods etc. The results show that γ-Fe2O3 is uniformly distributed around BiOI nanosheets in the γ-Fe2O3/BiOI sample, thus making the p-n heterojunction composite catalyst material which features the band gap of 1.75 eV, the average pore size of 6.756 nm, the specific surface area of 46.722 m²/g and good superparamagnetism. It is also used to degrade organic dyes (methyl orange, MO) and antibiotics (sulfapyridine, SP) in waste water. Irradiated by tungsten lamp for 120 min with the composite catalyst material as the catalyst, MO has the photocatalytic degradation efficiency of 67.6% and SP of 64.1%, 20% and 30% higher than those when pure BiOI is used as the catalyst, respectively. The composite catalyst still maintains excellent catalyst efficiency after five times recycling. The enhanced catalytic performance of the composite material is attributed to the effective separation of the electrons and holes in p-n heterojunction built by γ-Fe2O3 and BiOI. The active species of the photodegradation process were h⁺ and •OH.

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Wettability of AlSi7Mg alloy on alumina, spinel, mullite and rutile and its influence on the aluminum melt filtration efficiency

Publication date: 15 July 2018
Source:Materials & Design, Volume 150
Author(s): Claudia Voigt, Lisa Ditscherlein, Eric Werzner, Tilo Zienert, Rafal Nowak, Urs Peuker, Natalia Sobczak, Christos G. Aneziris
Despite the application of aluminum melt filtration with ceramic foam filters since the 1960s the process is not fully understood. Outstanding issues are for example the influence of the wetting behavior and filter chemistry on the filtration efficiencies.Contact angle measurements by the sessile drop method coupled with non-contact heating and capillary purification technique were conducted at 730 °C with AlSi7Mg alloy on the substrates of four different oxides (Al2O3, MgAl2O4, 3Al2O3·2SiO2 and TiO2). The highest contact angle was measured on 3Al2O3·2SiO2, followed by MgAl2O4, Al2O3 and TiO2.Experimental values of contact angles were correlated with the evaluated filtration efficiencies of filtration trials performed at Constellium. They show a good correlation for inclusions smaller than 110 μm - the larger the contact angle the higher is the filtration efficiency.The adhesion forces of alumina inclusions on the four filter materials were experimentally estimated with an AFM in water based model system. The highest adhesion forces were measured on the Al2O3 substrate, followed by the 3Al2O3·2SiO2, the MgAl2O4 and the TiO2 substrate. For inclusions >70 μm, both the measured filtration efficiencies for >70 μm and the adhesion forces increase by the following order of coatings: TiO2, 3Al2O3·2SiO2, MgAl2O4, Al2O3.

Graphical abstract

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Biocompatible magnetic nanocomposite microcapsules as microfluidic one-way diffusion blocking valves with ultra-low opening pressure

Publication date: 15 July 2018
Source:Materials & Design, Volume 150
Author(s): Meng-Chun Hsu, Ahmed Alfadhel, Farzad Forouzandeh, David A. Borkholder
A one-of-a-kind biocompatible magnetic nanocomposite microcapsule is developed as an in-line passive valve that can be integrated with micropumps and microfluidics. The magnetic nanocomposites act as the core for building a valve that utilizes the magnetic force attraction for sealing the microfluidic channels. The nanocomposites, molded with commercial microtubings, are prepared by incorporating Fe3O4 nanoparticles into polyethylene-glycol (PEG). Parylene-C provides a flexible, biocompatible shell and moisture barrier for the microcapsule that enables deformation and sealing to the microfluidic channel wall. The highly customizable valve design offers easy scalability and simplicity for integration into microfluidic systems. The presented magnetically-responsive microcapsule demonstrates reliable performance as a passive one-way valve that exhibits unique features and capabilities including effective flow-rectification with steady flows, extremely low leakage flows from backpressures at a rate of 4.7 nL/min kPa⁻¹, successfully blocking 99.96% of the diffusion, and extremely low inlet flow opening pressure of 2.1 kPa.

Graphical abstract

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Astroblastoma – a rare and challenging tumor: a case report and review of the literature

Astroblastoma is a controversial and an extremely rare central nervous system neoplasm. Although its histogenesis has been clarified recently, controversies exist regarding its cellular origin and validity as ...

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An asymptotic theory for cross-correlation between auto-correlated sequences and its application on neuroimaging data

Publication date: Available online 20 April 2018
Source:Journal of Neuroscience Methods
Author(s): Yunyi Zhou, Chenyang Tao, Wenlian Lu, Jianfeng Feng
BackgroundFunctional connectivity is among the most important tools to study brain. The correlation coefficient, between time series of different brain areas, is the most popular method to quantify functional connectivity. Correlation coefficient in practical use assumes the data to be temporally independent. However, the time series data of brain can manifest significant temporal auto-correlation.New methodA widely applicable method is proposed for correcting temporal auto-correlation. We considered two types of time series models: (1) auto-regressive-moving-average model, (2) nonlinear dynamical system model with noisy fluctuations, and derived their respective asymptotic distributions of correlation coefficient. These two types of models are most commonly used in neuroscience studies. We show the respective asymptotic distributions share a unified expression.ResultWe have verified the validity of our method, and shown our method exhibited sufficient statistical power for detecting true correlation on numerical experiments. Employing our method on real dataset yields more robust functional network and higher classification accuracy than conventional methods.Comparison with existing methodsOur method robustly controls the type I error while maintaining sufficient statistical power for detecting true correlation in numerical experiments, where existing methods measuring association (linear and nonlinear) fail.ConclusionsIn this work, we proposed a widely applicable approach for correcting the effect of temporal auto-correlation on functional connectivity. Empirical results favors the use of our method in functional network analysis.



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Short Takes

Publication date: Available online 20 April 2018
Source:Pediatric Neurology
Author(s): Steven G. Pavlakis




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Ecotoxicological effects of microplastics on biota: a review

Abstract

The ubiquitous presence of microplastics in the environment has drawn the attention of ecotoxicologists on its safety and toxicity. Sources of microplastics in the environment include disintegration of larger plastic items (secondary microplastics), personal care products like liquid soap, exfoliating scrubbers, and cleaning supplies etc. Indiscriminate usage of plastics and its poor waste disposal management pose serious concern on ecosystem quality at global level. The present review focused on the ecological impact of microplastics on biota at different trophic levels, its uptake, accumulation, and excretion etc., and its plausible mechanistic toxicity with risk assessment approaches. Existing scientific evidence shows that microplastics exposure triggers a wide variety of toxic insult from feeding disruption to reproductive performance, physical ingestion, disturbances in energy metabolism, changes in liver physiology, synergistic and/ or antagonistic action of other hydrophobic organic contaminants etc. from lower to higher trophics. Thus, microplastic accumulation and its associated adverse effects make it mandatory to go in for risk assessment and legislative action. Subsequent research priorities, agenda, and key issues to be addressed are also acknowledged in the present review.

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Modernising speech audiometry: using a smartphone application to test word recognition.

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Modernising speech audiometry: using a smartphone application to test word recognition.

Int J Audiol. 2018 Apr 20;:1-9

Authors: van Zyl M, Swanepoel W, Myburgh HC

Abstract
OBJECTIVE: This study aimed to develop and assess a method to measure word recognition abilities using a smartphone application (App) connected to an audiometer.
DESIGN: Word lists were recorded in South African English and Afrikaans. Analyses were conducted to determine the effect of hardware used for presentation (computer, compact-disc player, or smartphone) on the frequency content of recordings. An Android App was developed to enable presentation of recorded materials via a smartphone connected to the auxiliary input of the audiometer. Experiments were performed to test feasibility and validity of the developed App and recordings.
STUDY SAMPLE: Participants were 100 young adults (18-30 years) with pure tone thresholds ≤15 dB across the frequency spectrum (250-8000 Hz).
RESULTS: Hardware used for presentation had no significant effect on the frequency content of recordings. Listening experiments indicated good inter-list reliability for recordings in both languages, with no significant differences between scores on different lists at each of the tested intensities. Performance-intensity functions had slopes of 4.05%/dB for English and 4.75%/dB for Afrikaans lists at the 50% point.
CONCLUSIONS: The developed smartphone App constitutes a feasible and valid method for measuring word recognition scores, and can support standardisation and accessibility of recorded speech audiometry.

PMID: 29676598 [PubMed - as supplied by publisher]

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Communication disorders in aging.

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Communication disorders in aging.

Int J Audiol. 2018 Apr 20;:1

Authors: Pillion J

PMID: 29676595 [PubMed - as supplied by publisher]

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Current practice of ototoxicity management across the United Kingdom (UK).

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Current practice of ototoxicity management across the United Kingdom (UK).

Int J Audiol. 2018 Apr 20;:1-13

Authors: Maru D, Malky GA

Abstract
OBJECTIVE: Effective management of patients diagnosed with ototoxicity is needed to reduce hearing and balance damage which affects communication and life quality. Despite widespread recommendations to monitor and manage ototoxicity in an early and effective manner, there is limited evidence to support the actual implementation of these recommendations for affected patient groups in healthcare services across the UK with limited publications available. In this study, an online questionnaire analysed the current practice of ototoxicity management and patient pathways across the UK once the diagnosis of ototoxicity was confirmed, targeting Audiologists, ENTs/AVPs and GPs.
DESIGN: Qualitative Survey Study.
STUDY SAMPLE: A randomised sample of hearing services in the UK, including audiology departments; GP practices and local health settings were targeted with a total of 134 completed surveys.
RESULTS: About 72% reported the absence of ototoxicity management protocols within their centre. Results depicted great inconsistency and variation across the UK in ototoxicity management services provided, treatment modification, monitoring and referral pathways.
CONCLUSION: Developing and advocating national guidelines are intended not only to inform clinical decision making but to provide minimum standards of care in ototoxicity management and offer greater awareness and education to improve patients' quality of life.

PMID: 29676584 [PubMed - as supplied by publisher]

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Lamellation in fibrous dysplasia: A clinicopathologic study.

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Lamellation in fibrous dysplasia: A clinicopathologic study.

Histol Histopathol. 2018 Apr 20;:11991

Authors: Cicek AF, Kilinc M, Safali M, Gunhan O

Abstract
BACKGROUND: Fibrous dysplasia (FD) is a maturation defect characterized by immature woven bones and stroma. However, especially in craniofacial bones, lamellation can be seen and this is associated with the maturation.
AIM: To show maturation in FD and discuss the factors that may affect the maturation.
MATERIALS AND METHODS: Ninety-five FD cases were divided into three subgroups according to the lamellation percentage as Groups 1, 2 and 3 (low, moderate and high lamellation, respectively). Each group was compared in terms of the peritrabecular clefting (PTC), stromal cellularity and the age. The lesions under pressure and the ones that are not were compared in terms of lamellation percentage.
RESULTS: A significant statistical difference was found between Groups 1 and 3 in terms of PTC, stromal cellularity, histologic pattern suggesting maturation (p<0.001, p<0.001, p=0.002, respectively).
CONCLUSION: The findings suggested a strong relation between lamellation and maturation. Lamellation was more prominent in the bones under pressure than the others. Considering lamellation as a finding of maturation, it is possible to establish a relation between maturation and pressure. Therefore, future studies should focus on the question if the pressure could be a factor for maturation and it could be used for treating FD.

PMID: 29675824 [PubMed - as supplied by publisher]

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PK/PD evaluation of fimasartan for the treatment of hypertension Current evidences and future perspectives.

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PK/PD evaluation of fimasartan for the treatment of hypertension Current evidences and future perspectives.

Expert Opin Drug Metab Toxicol. 2018 Apr 20;:

Authors: Angeli F, Verdecchia P, Trapasso M, Pane M, Signorotti S, Reboldi G

Abstract
INTRODUCTION: Fimasartan is the ninth and latest Angiotensin Receptor Blockers for the treatment of hypertension. Fimasartan is a derivative of losartan in which the imidazole ring has been replaced, a change that provided higher potency and longer duration than losartan. It provides a selective type 1 angiotensin II receptor antagonist effect with noncompetitive, insurmountable binding. Fimasartan is rapidly absorbed following oral administration with an oral bioavailability of 18.6 ± 7.2 %. Fimasartan is relatively stable in terms of metabolism and more than 90 % of circulating fimasartan moieties in the plasma are in the parent form; fecal elimination and biliary excretion are the predominant elimination pathways of fimasartan. Areas covered. We reviewed data from clinical trials that investigated safety and efficacy of fimasartan in hypertension. The literature search was conducted using PubMed and Scopus together with the Google Scholar database. Expert opinion. Fimasartan proved good efficacy in blood pressure reduction. In large clinical studies, fimasartan showed an excellent safety profile and when combined with hydrochlorothiazide or amlodipine, it showed a better effect on controlling blood pressure than monotherapy. Fimasartan 60-120 mg once daily has also shown an antihypertensive effect over 24-h. Moreover, preclinical studies demonstrated organ-protecting effects of fimasartan. These results make fimasartan an attractive candidate for the treatment of hypertension. However, given the evidence of potentially important pharmacological differences from other agents of the same class, it remains to test the benefit of using fimasartan on clinical outcomes.

PMID: 29676941 [PubMed - as supplied by publisher]

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The Application of SVR Model in the Improvement of QbD: A case study of the extraction of podophyllotoxin.

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The Application of SVR Model in the Improvement of QbD: A case study of the extraction of podophyllotoxin.

Drug Dev Ind Pharm. 2018 Apr 20;:1-24

Authors: Zhai CH, Xuan JB, Fan HL, Zhao TF, Jiang JL

Abstract
In order to make a further optimization of process design via increasing the stability of design space, we brought in the model of Support Vector Regression (SVR). In this work, the extraction of podophyllotoxin was researched as a case study based on QbD. We compared the fitting effect of SVR and the most used quadratic polynomial model (QPM) in QbD, and an analysis was made between the two design spaces obtained by SVR and QPM. As a result, the SVR stayed ahead of QPM in prediction accuracy, the stability of model and the generalization ability. The introduction of SVR into QbD made the extraction process of podophyllotoxin well designed and easier to control. The better fitting effect of SVR improved the application effect of QbD and the universal applicability of SVR, especially for nonlinear, complicated and weak-regularity problems, widened the application field of QbD.

PMID: 29676171 [PubMed - as supplied by publisher]

https://ift.tt/2HJNXVk