Fate and behavior of dissolved organic matter in a submerged anoxic-aerobic membrane bioreactor (MBR)

Abstract

In this study, the production, composition, and characteristics of dissolved organic matter (DOM) in an anoxic-aerobic submerged membrane bioreactor (MBR) were investigated. The average concentrations of proteins and carbohydrates in the MBR aerobic stage were 3.96 ± 0.28 and 8.36 ± 0.89 mg/L, respectively. After membrane filtration, these values decreased to 2.9 ± 0.2 and 2.8 ± 0.2 mg/L, respectively. High performance size exclusion chromatograph (HP-SEC) analysis indicated a bimodal molecular weight (MW) distribution of DOMs, and that the intensities of all the peaks were reduced in the MBR effluent compared to the influent. Three-dimensional fluorescence excitation emission matrix (FEEM) indicated that fulvic and humic acid-like substances were the predominant DOMs in biological treatment processes. Precise identification and characterization of low-MW DOMs was carried out using gas chromatography-mass spectrometry (GC-MS). The GC-MS analysis indicated that the highest peak numbers (170) were found in the anoxic stage, and 54 (32%) compounds were identified with a similarity greater than 80%. Alkanes (28), esters (11), and aromatics (7) were the main compounds detected. DOMs exhibited both biodegradable and recalcitrant characteristics. There were noticeable differences in the low-MW DOMs present down the treatment process train in terms of numbers, concentrations, molecular weight, biodegradability, and recalcitrance.

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Sewage sludge as a soil amendment in a Larix decidua plantation: Effects on tree growth and floristic diversity

Publication date: 15 April 2018
Source:Science of The Total Environment, Volume 621
Author(s): Bourioug Mohamed, Girardclos Olivier, Gillet François, Alaoui-Sehmer Laurence, Pascale Bourgeade, Alaoui-Sossé Badr, Aleya Lotfi
Sewage sludge application in forest plantations is an interesting complementary alternative practice to sewage sludge reutilization and recycling, with a significant and sustainable net effect in climate change mitigation. However, to optimize it a detailed knowledge of its effects on ecosystem components such as plants, soil, water and fauna is needed. We investigated the effects of sewage sludge application on soil, tree growth and floristic diversity in a ten-year-old plantation of European larch (Larix decidua Mill.). Our one-hectare study site, located at Mélisey, Haute-Saône, France (47°753′ Lat., 6°580′ Long.), was subdivided into six plots. Three plots, alternating with three control plots (no sewage sludge application), were amended in June 2008 with 0.4tDWha⁻¹ obtained from a municipal urban wastewater treatment plant in Mélisey. Within each plot, one subplot was delimited and sludge was again manually applied at 3t of DWha⁻¹ in July 2009 and March 2010 to the soil surface of the amended subplots without incorporation. The results showed no effect on radial and height growth of European larch amended with 0.4tDWha⁻¹. While a significant temporary increase in pH, macro-element contents (N, P and Ca) and the trace metal (Cu and Zn) concentration in the soil was observed, it had no significant effect on needles and sporocarp contents. The number of species in the amended subplots with 3tDWha⁻¹year⁻¹ increased by 80% compared to the control. However, the relative species abundance present only in amended subplots remains <1, except for Hypericum humifusum.

Graphical abstract

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Ternary complexes of Zn(II) and Cu(II) with 1-((2-hydroxynaphthalen-1-yl)methylene)-4-phenylthiosemicarbazide in the presence of heterocyclic bases as auxiliary ligands: Synthesis, spectroscopic and structural characterization and antibacterial activity

Publication date: 15 March 2018
Source:Journal of Molecular Structure, Volume 1156
Author(s): Mohammad Azarkish, Alireza Akbari, Tahereh Sedaghat, Jim Simpson
The new ternary complexes, ZnLL′ [L = 1-((2-hydroxynaphthalen-1-yl)methylene)-4-phenylthiosemicarbazide and L′ = imidazole (1), 2, 2′-bipyridine (2) and 2-methyimidazole (3)], Zn2L2L′ [L′ = 4, 4′-bipy (4)] and CuLL′ [L′ = 2, 2′-bipy (5)] have been synthesized by the reaction of a metal(II) acetate salt with the thiosemicarbazone and in presence of heterocyclic bases as auxiliary ligands. The synthesized compounds were investigated by elemental analysis and IR, ¹H NMR, and ¹³C NMR spectroscopy and complex 5 was structurally characterized by X-ray crystallography. The results indicate the thiosemicarbazone doubly deprotonated and coordinates to metal through the thiolate sulfur, imine nitrogen and phenolic oxygen atoms. The nitrogen atom(s) of the auxiliary ligand complete the coordination sphere. Complex 4 is binuclear with 4, 4′-bipy acting as a bridging ligand. The structure of 5 is a distorted square pyramid with one of the bipyridine nitrogen atoms in the apical position. This compound creates an inversion dimer in solid state by intermolecular hydrogen bonds of NH⋯S type. The in vitro antibacterial activity of the synthesized compounds were evaluated against Gram-positive (B. subtilis and S. aureus) and Gram-negative (P. aeruginosa) bacteria and is compared to that of standard antibacterial drugs. All complexes exhibit good inhibitory effects and are significantly more effective than the parent ligand.

Graphical abstract

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Collar occupancy: A new quantitative imaging tool for morphometric analysis of oligodendrocytes

Publication date: 15 January 2018
Source:Journal of Neuroscience Methods, Volume 294
Author(s): Filipa Bouçanova, André Filipe Maia, Andrea Cruz, Val Millar, Inês Mendes Pinto, João Bettencourt Relvas, Helena Sofia Domingues
BackgroundOligodendrocytes (OL) are the myelinating cells of the central nervous system. OL differentiation from oligodendrocyte progenitor cells (OPC) is accompanied by characteristic stereotypical morphological changes. Quantitative imaging of those morphological alterations during OPC differentiation is commonly used for characterization of new molecules in cell differentiation and myelination and screening of new pro-myelinating drugs. Current available imaging analysis methods imply a non-automated morphology assessment, which is time-consuming and prone to user subjective evaluation.New methodHere, we describe an automated high-throughput quantitative image analysis method entitled collar occupancy that allows morphometric ranking of different stages of in vitro OL differentiation in a high-content analysis format. Collar occupancy is based on the determination of the percentage of area occupied by OPC/OL cytoplasmic protrusions within a defined region that contains the protrusion network, the collar.ResultsWe observed that more differentiated cells have higher collar occupancy and, therefore, this parameter correlates with the degree of OL differentiation.Comparison with existing methodsIn comparison with the method of manual categorization, we found the collar occupancy to be more robust and unbiased. Moreover, when coupled with myelin basic protein (MBP) staining to quantify the percentage of myelinating cells, we were able to evaluate the role of new molecules in OL differentiation and myelination, such as Dusp19 and Kank2.ConclusionsAltogether, we have successfully developed an automated and quantitative method to morphologically characterize OL differentiation in vitro that can be used in multiple studies of OL biology.

Graphical abstract

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Role of rotavirus vaccination on an emerging G8P[8] rotavirus strain causing an outbreak in central Japan

Publication date: Available online 26 November 2017
Source:Vaccine
Author(s): Sheikh Ariful Hoque, Masaaki Kobayashi, Sayaka Takanashi, Kazi Selim Anwar, Taeko Watanabe, Pattara Khamrin, Shoko Okitsu, Satoshi Hayakawa, Hiroshi Ushijima
BackgroundIn this study, we examined the effectiveness of RV1 and RV5 vaccines during an outbreak of G8P[8] rotavirus group A strain (G8P[8]-RVA). These vaccines were originally designed to provide protection against severe diseases caused by common circulating strains, whereas G8P[8]-RVA remains emerging strain and partially heterotypic to the vaccines. It is imperative to investigate vaccine effectiveness (VE) against G8P[8]-RVA because this strain appears to be predominant in recent years, particularly, in post-vaccine era.MethodsRVA infection and genotypes were confirmed by polymerase chain reaction (PCR) followed by sequence-based genotyping. VE was determined during an outbreak of G8P[8]-RVA in Shizuoka Prefecture, Japan, in February-July 2017, retrospectively, by comparing vaccination status of children suffering from acute gastroenteritis (AGE) between 'PCR-positive' and 'PCR-negative' cases using conditional logistic regression adjusted for age.ResultsAmong 80 AGE children, RVA was detected in 58 (73%), of which 53 (66%) was G8P[8]-RVA. The clinical characteristics of G8P[8]-RVA and other RVA strains were identically severe. Notably, the attack rates of G8P[8]-RVA in vaccinated (61.1%) and unvaccinated (65.5%) children were almost similar. Indeed, no substantial effectiveness were found against G8P[8]-RVA (VE, 14% [95% CI: −140% to 70%]) or other RVA strains (VE, 58% [95% CI: −20% to 90%]) for mild infections. However, these vaccines remained strongly effective against moderate (VE, 75% [95% CI: 1% to 40%]) and severe (VE, 92% [95% CI: 60% to 98%]) RVA infections. The disease severity including Vesikari score, duration and frequency of diarrhea, and body temperature were significantly lower in vaccinated children.ConclusionsThis study demonstrates the effectiveness of current RV vaccines against moderate and severe, but not against the mild infections during an outbreak caused by unusual G8P[8]-RVA, which was virtually not targeted in the vaccines.



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Measles and rubella eradication

Publication date: Available online 26 November 2017
Source:Vaccine
Author(s): Alan R. Hinman
This article discusses concepts of eradication, some issues relating to vertical and horizontal public health programs, some current issues relating to measles and rubella, and what we need to do about them. It concludes that measles and rubella/CRS can and should be eradicated. A target date should be established in 2020 (or before). Eradication can only be accomplished in the context of strengthening ongoing immunization services and strengthening surveillance so it can guide activities. Additional resources will be required to achieve the goal.



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Vaccine hesitancy terminology: A response to Bedford et al.

Publication date: Available online 26 November 2017
Source:Vaccine
Author(s): Noni MacDonald, Eve Dubé, Robb Butler




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Meningococcal carriage among a university student population – United States, 2015

Publication date: Available online 26 November 2017
Source:Vaccine
Author(s): Lucy Breakwell, Melissa Whaley, Unab I. Khan, Utpala Bandy, Nicole Alexander-Scott, Lynn Dupont, Cindy Vanner, How-Yi Chang, Jeni T. Vuong, Stacey Martin, Jessica R. MacNeil, Xin Wang, Sarah A. Meyer
ObjectivesSeveral outbreaks of serogroup B meningococcal disease have occurred among university students in recent years. In the setting of high coverage of the quadrivalent meningococcal conjugate vaccine and prior to widespread use of serogroup B meningococcal vaccines among adolescents, we conducted surveys to characterize the prevalence and molecular characteristics of meningococcal carriage among university students.MethodsTwo cross-sectional oropharyngeal carriage surveys were conducted among undergraduates at a Rhode Island university. Isolates were characterized using slide agglutination, real-time polymerase chain reaction (rt-PCR), and whole genome sequencing. Adjusted prevalence ratios and 95% confidence intervals were calculated using Poisson regression to determine risk factors for carriage.ResultsA total of 1837 oropharyngeal specimens were obtained from 1478 unique participants. Overall carriage prevalence was 12.7–14.6% during the two survey rounds, with 1.8–2.6% for capsular genotype B, 0.9–1.0% for capsular genotypes C, W, or Y, and 9.9–10.8% for nongroupable strains by rt-PCR. Meningococcal carriage was associated with being male, smoking, party or club attendance, recent antibiotic use (inverse correlation), and recent respiratory infections.ConclusionsIn this university setting, the majority of meningococcal carriage was due to nongroupable strains, followed by serogroup B. Further evaluation is needed to understand the dynamics of serogroup B carriage and disease among university students.



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Immune memory at 17-years of follow-up of a single dose of live attenuated hepatitis A vaccine

Publication date: Available online 26 November 2017
Source:Vaccine
Author(s): Ying Chen, Chen-Liang Zhou, Xin-Jiang Zhang, Zhi-Yong Hao, Yan-Hong Zhang, Song-Mei Wang, Jing-Chen Ma, Gan Zhao, Chao Qiu, Yu-Liang Zhao, Bin Wang, Xuan-Yi Wang
BackgroundIn recent years, hepatitis A virus (HAV) infection has declined considerably in China, associated with wide deployment of HAV vaccines and improvement in socio-economic indicators. Towards the elimination of HA in the country, we assessed the duration and characteristics of immunity conferred by the widely used, locally manufactured HAV vaccine.MethodsThis is a longitudinal cohort study that followed recipients of a live attenuated HAV vaccine 17 years after the initial administration. Blood samples were collected from participants pre- and two-week post-booster HAV vaccine dose. Serum anti-HAV antibody was measured by ELISA method. Memory B and T cells were determined by ELISPOT and Flow Cytometry assays, respectively.ResultsA robust anamnestic response was observed two-week post-challenge. Both HAV-specific memory B cell and T cells remained, and responded quickly when re-encountering HAV. The magnitude of recall responses was present, regardless of the status of the serum anti-HAV antibody pre-booster.ConclusionsWe demonstrated long-term immunity from the live attenuated HAV vaccine, including antibody persistence and immunological memory. Considering the conditions that make elimination of infectious diseases feasible, following polio, hepatitis A could be targeted for elimination in China.



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The Idea of Beauty and Its Biases: Critical Notes on the Aesthetics of Plastic Surgery

Summary: Two biases affect the idea of beauty often embodied in aesthetic surgery. The first one is that the living body is the sum of different parts; the second one claims that beauty results from the sum of beautiful elements. Taken together, these 2 biases explain most of the aesthetic surgery procedures, in which a localized improvement is supposed to impact on the whole body image. In this article, I put into question these 2 problematic assumptions, showing that Western and Eastern aesthetics, on one side, and philosophical reflections, on the other side, support a different conception of beauty. In particular, an alternative idea that opens to authenticity and imperfection and focuses on the living body rather than on the mere anatomical surface is proposed here as a more adequate concept of beauty for aesthetic surgery.

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Diurnal and seasonal trends and source apportionment of redox-active metals in Los Angeles using a novel online metal monitor and Positive Matrix Factorization (PMF)

Publication date: February 2018
Source:Atmospheric Environment, Volume 174
Author(s): Amirhosein Mousavi, Mohammad H. Sowlat, Constantinos Sioutas
In the present study, we identified the sources of four redox-active metals, including Iron (Fe), Chromium (Cr), Cupper (Cu), and Manganese (Mn) and quantified the contribution of these sources to PM2.5 concentrations in central Los Angeles, California, by employing time-resolved measurements (i.e., a time resolution of 2 h) with a recently developed online metal monitor and Positive Matrix Factorization (PMF). Size distribution of ambient PM (14 nm–10 μm) was measured using the Scanning Mobility Particle Sizer (SMPS) and Optical Particle Sizer (OPS). Auxiliary variables were also collected, including elemental (EC) and organic carbon (OC), gaseous pollutants (NO2 and O3), meteorological parameters (including relative humidity (RH) and temperature), and traffic data (for heavy- (HDVs) and light-duty vehicles (LDVs)). A 4-factor solution was found to be optimum for the chemically-speciated dataset, whereas a 5-factor solution appeared to be most plausible for the size distribution data. The factors included fresh traffic, soil/road dust, urban background aerosol, secondary aerosol, and nucleation (only resolved for the size distribution data). Fresh traffic was the major contributor to Fe and Cu concentrations, whereas Cr was mostly found in the urban background aerosol (reflecting a mixture of small local sources as well as aged traffic emissions), and Mn mostly came from both soil/road dust and was to a lesser degree found in urban background aerosol. Secondary aerosol did not contribute to the concentrations of any of these metals, but was associated with very high loading of OC, as expected. Even though the urban background aerosol and secondary aerosol appeared to be characterized by "aged" particles and have a rather homogeneous spatial distribution, the reactions and processes involved in their formation are entirely different. Our results provide insights into the sources of redox-active metals in central Los Angeles. They also underscore the benefits of novel measurement techniques for PM-bound metals, which could enhance our understanding of the sources of atmospheric aerosols by providing us with measurements with finer time resolutions that otherwise would not have been possible using traditional filter-based measurement techniques.



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Coordinated profiling of stratospheric intrusions and transported pollution by the Tropospheric Ozone Lidar Network (TOLNet) and NASA Alpha Jet experiment (AJAX): Observations and comparison to HYSPLIT, RAQMS, and FLEXPART

Publication date: February 2018
Source:Atmospheric Environment, Volume 174
Author(s): A.O. Langford, R.J. Alvarez, J. Brioude, S. Evan, L.T. Iraci, G. Kirgis, S. Kuang, T. Leblanc, M.J. Newchurch, R.B. Pierce, C.J. Senff, E.L. Yates
Ground-based lidars and ozonesondes belonging to the NASA-supported Tropospheric Ozone Lidar Network (TOLNet) are used in conjunction with the NASA Alpha Jet Atmospheric eXperiment (AJAX) to investigate the transport of stratospheric ozone and entrained pollution into the lower troposphere above the United States on May 24–25, 2013. TOLNet and AJAX measurements made in California, Nevada, and Alabama are compared to tropospheric ozone retrievals from the Atmospheric Infrared Sounder (AIRS), to back trajectories from the NOAA Air Resources Laboratory (ARL) Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model, and to analyses from the NOAA/NESDIS Real-time Air Quality Modeling System (RAQMS) and FLEXPART particle dispersion model. The measurements and model analyses show much deeper descent of ozone-rich upper tropospheric/lower stratospheric air above the Desert Southwest than above the Southeast, and comparisons to surface measurements from regulatory monitors reporting to the U.S. EPA Air Quality System (AQS) suggest that there was a much greater surface impact in the Southwest including exceedances of the 2008 National Ambient Air Quality Standard (NAAQS) of 0.075 ppm in both Southern California and Nevada. Our analysis demonstrates the potential benefits to be gained by supplementing the existing surface ozone network with coordinated upper air observations by TOLNet.



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Functional characterization of the dual allatostatin-A receptors in mosquitoes

Publication date: January 2018
Source:Peptides, Volume 99
Author(s): Peter Christ, Sharon R. Hill, Joachim Schachtner, Frank Hauser, Rickard Ignell
The neuropeptide allatostatin-A (AstA) and its cognate receptors (AstARs) are involved in the modulation of feeding behavior, which in hematophagous insects includes the regulation of the disease vector-related behaviors, host seeking and blood feeding. In mosquitoes and other dipterans, there are two copies of AstAR, contrasting with the single copy found in other insects. In this study, we identified and cloned the dual AstAR system of two important disease vectors Aedes aegypti and Culex quinquefasciatus, and compared them with those previously described, including those in Anopheles coluzzii and Drosophila melanogaster. Phylogenetic analysis of the AstARs revealed that the mosquito AstAR1s has retained a similar amino acid sequence as the AstARs from non-dipteran insect species. Intron analysis revealed that the number of introns accumulated in the AstAR2s is similar to that in other insects, and that introns are conserved within the receptor types, but that only the final two introns are conserved across AstAR1s and 2s. We functionally characterized the dual AstARs in An. coluzzii, Ae. aegypti and Cx. quinquefasciatus by stably expressing the receptors in a Chinese hamster oocyte cell line (CHO) also stably expressing a promiscuous G-protein (G16), and challenged them with the endogenous isoforms of AstA from the three mosquito species. In the culicine mosquitoes, Ae. aegypti and Cx. quinquefasciatus, the AstARs demonstrated differential sensitivity to AstA, with the AstAR2s displaying a higher sensitivity than the AstAR1s, suggesting a divergence of functional roles for these AstARs. In contrast, both An. coluzzii AstARs demonstrated a similar sensitivity to the AstA ligands. We discuss our findings in the light of AstA acting as a regulator of blood feeding in mosquitoes. A better understanding of the regulation of host seeking and blood feeding in vector mosquitoes will lead to the rational development of novel approaches for vector control.

Graphical abstract

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Structural determination, distribution, and physiological actions of ghrelin in the guinea pig

Publication date: Available online 26 November 2017
Source:Peptides
Author(s): Yuji Okuhara, Hiroyuki Kaiya, Hiroki Teraoka, Takio Kitazawa
We identified guinea pig ghrelin (gp-ghrelin), and examined its distribution and physiological actions in the guinea-pig. Gp-ghrelin is a 28-amino acid peptide (GASFR SPEHH SAQQR KESRK LPAKI QPR); seven amino acids are different from that of rat ghrelin at positions 2, 5, 10, 11, 19, 21, and 25, which include the conserved region known in mammals. The third serine residue is mainly modified by n-decanoyl acid. Both gp-ghrelin and rat ghrelin increased intracellular Ca²⁺ concentration of HEK293 cells expressing guinea pig growth hormone secretagogue receptor 1a (GHS-R1a), and the affinity of gp-ghrelin was slightly higher than that of rat ghrelin. In addition, gp-ghrelin was also effective in CHO cells expressing rat GHS-R1a with similar affinity to that of rat ghrelin. Gp-ghrelin mRNA was predominantly expressed in the stomach, whereas the expression levels in other organs was low. High levels of GHS-R1a mRNA expression were observed in the pituitary, medulla oblongata, and kidney, while medium levels were noted in the thalamus, pons, olfactory bulb, and heart. Immunohistochemistry identified gp-ghrelin-immunopositive cells in the gastric mucosa and pancreas. Intraperitoneal injection of gp-ghrelin increased food intake in the guinea pig. Gp-ghrelin did not cause any mechanical responses in isolated gastrointestinal smooth muscles in vitro, similar to rat ghrelin. In conclusion, the N-terminal structures that are conserved in mammals were different in gp-ghrelin. Moreover, the functional characteristics of gp-ghrelin, other than its distribution, were dissimilar from those in other Rodentia.



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A new tridecapeptide with an octaarginine vector has analgesic therapeutic potential and prevents morphine-induced tolerance

Publication date: Available online 24 November 2017
Source:Peptides
Author(s): Vladimir A. Kashkin, Elena V. Shekunova, Michail I. Titov, Ivan I. Eliseev, Maxim A. Gureev, Yuri B. Porozov, Marina N. Makarova, Valery G. Makarov
A growing body of evidence suggests that peptides may possess analgesic effects without tolerance development. The synthetic tetrapeptide Tyr-D-Arg-Phe-Gly-NH2 was modified with the inclusion of a (D-Arg)8 vector to prevent the action of endopeptidase and to increase the duration of the analgesic action of the tetrapeptide when administered orally. The aim of this study was to estimate the analgesic efficacy of the tetrapeptide with (D-Arg)8 (tridecapeptide, TDP) in experimental models of acute and chronic pain. The analgesic effects of TDP were estimated using a model of acute visceral pain in mice (writhing test) and a model of chronic neuropathic pain (chronic constriction injury (CCI) of the sciatic nerve) in rats. The intravenous administration of morphine (0.32–1mg/kg) and TDP (0.32–1.8mg/kg) produced significant dose-related antinociceptive effects in the writhing test. The potency of TDP after i.g. administration was lower than that after i.v. administration but comparable with that of i.g. morphine. In the CCI model, TDP (0.1, 1 and 10mg/kg, i.g.) induced marked analgesia with repeated administration without any signs of tolerance. The single administration of TDP after morphine treatment (7 days) produced a significant analgesic effect in morphine-tolerant rats, indicating the absence of cross-tolerance between these two drugs. The combined administration of TDP and morphine resulted in the reduction of analgesic tolerance to morphine. The absence of cross-tolerance to morphine and the ability to prevent morphine tolerance allows this compound to be a prospective candidate for chronic pain therapy. In order to find the target receptors for TDP, a docking study was performed. It was found that the molecule can bind to the NMDA receptor using electrostatic, hydrogen bonding and hydrophobic interactions.



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Invasive fungi-derived defensins kill drug-resistant bacterial pathogens

Publication date: Available online 22 November 2017
Source:Peptides
Author(s): Jiajia Wu, Shijie Liu, Hao Wang
Fungi-derived defensins are a class of antimicrobial peptides with therapeutic potential due to their high antibacterial efficacy and low toxicity. Based on the genomic strategy, we have identified 68 fungal defensin-like peptides (fDLPs) in five new genera, including Trichosporon, Apophysomyces, Lichtheimia, Beauveria and Scedosporium and characterized a new synthetic defensin (scedosporisin) from an invasive fungus. It was active against Gram-positive bacteria but not active against negative bacteria. Importantly, it killed several clinical resistant isolates such as methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococci at low molecular concentrations. Scedosporisin showed low hemolysis and cytotoxicity and high serum stability. The killing kinetics of scedosporisin-2 against a clinical isolate of MRSA showed that it killed the bacteria more rapidly than that of vancomycin. Homology modeling analysis show that scedosporisin adopted a typical cysteine stabilized α-helical and β-sheet fold with a local hydrophobic patch. Scedosporisin significantly improved the survival rate of mice in the peritonitis model. This work has greatly expanded the library of fDLPs, and successfully selected leading molecules for antimicrobial drug reserves.



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Evaluation of the insulinotropic and glucose-lowering actions of zebrafish GIP in mammalian systems: Evidence for involvement of the GLP-1 receptor

Publication date: Available online 20 November 2017
Source:Peptides
Author(s): Galyna V. Graham, J. Michael Conlon, Yasser H. Abdel-Wahab, Victor A. Gault, Peter R. Flatt
The insulinotropic properties of zebrafish GIP (zfGIP) were assessed in vitro using clonal pancreatic β-cell lines and isolated mouse islets and acute effects on glucose tolerance and insulin release in vivo were evaluated in mice. The peptide produced a dose-dependent increase in the rate of insulin release from BRIN-BD11 rat clonal β-cells at concentrations ≥30nM. Insulin release from 1.1 B4 human clonal β-cells and mouse islets was significantly increased by zfGIP (10nM and 1μM). The in vitro insulinotropic activity of zfGIP was decreased after incubating BRIN-BD11 cells with the GLP-1 receptor antagonist, exendin-4(9-39) (p<0.001) and the GIP receptor antagonist, GIP (6-30) Cex-K⁴⁰[Pal] (p<0.05) but the glucagon receptor antagonist [des-His¹,Pro⁴,Glu⁹]glucagon amide was without effect. zfGIP (10nM and 1μM) produced significant increases in cAMP concentration in CHL cells transfected with the human GLP-1 receptor but was without effect on HEK293 cells transfected with the human glucagon receptor. Conversely, zfGIP, but not human GIP, significantly stimulated insulin release from CRISPR/Cas9-engineered INS-1 clonal β-cells from which the GIP receptor had been deleted. Intraperitoneal administration of zfGIP (25 and 75nmol/kg body weight) to mice together with an intraperitoneal glucose load (18mmol/kg body weight) produced a significant decrease in plasma glucose concentrations concomitant with an increase in insulin concentrations. The study provides evidence that the insulinotropic action of zfGIP in mammalian systems involves activation of both the GLP-1 and the GIP receptors but not the glucagon receptor.



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Adverse events of Dupilumab in adults with moderate-to-severe atopic dermatitis: A meta-analysis

Publication date: January 2018
Source:International Immunopharmacology, Volume 54
Author(s): Zuzhen Ou, Chao Chen, Aijun Chen, Yao Yang, Weikang Zhou
BackgroundDupilumab, a fully human monoclonal antibody against interleukin-4 receptor alpha, inhibits the signals of interleukin-4 and interleukin-13, and has also shown significant efficacy in patients with moderate-to-severe atopic dermatitis (AD), while the effect of it on adverse events remains controversial.ObjectiveTo assess the influence of dupilumab on adverse events in adults with moderate-to-severe AD.MethodRandomised controlled trials (RCTs) that compared dupilumab with a placebo for patients with moderate-to-severe AD were searched in the MEDLINE, EMBASE, Web of Science and Cochrane databases. The outcome of the study was the incidence of adverse events during the observation period.ResultsEight RCTs were analysed in this study. Meta-analysis showed that patients treated with dupilumab had a lower risk of skin infection (risk ratio [RR] 0.54; 95% confidence interval [CI] 0.42–0.69) and exacerbation of AD (RR 0.44, 95% CI 0.34–0.59), but had a higher risk of injection-site reaction (RR 2.24, 95% CI 1.68–2.99), headache (RR 1.47, 95% CI 1.05–2.06), and conjunctivitis (RR 2.64, 95% CI 1.79–3.89) than did patients treated with a placebo. Nasopharyngitis, urinary tract infection, upper respiratory tract infection, and herpes virus infection were found balanced in dupilumab groups and placebo groups.ConclusionDupilumab moderately reduced the risk of skin infection and the exacerbation of AD, slightly increased the risk of headache, and moderately increased the risk of injection-site reaction and conjunctivitis, but had little effect on other infections in adults with moderate-to-severe AD.



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Cu(II)-catalyzed degradation of ampicillin: effect of pH and dissolved oxygen

Abstract

Cu(II)-catalyzed hydrolysis of β-lactam antibiotics has been well-identified and recognized as the key mechanism of antibiotic degradation. However, the overlooked Cu(II) oxidation susceptibly also plays an important role comparably with hydrolysis. This study evaluated the roles of hydrolysis and oxidation in Cu(II)-catalyzed degraded ampicillin (AMP), as a typical β-lactam antibiotic, under relevant environmental conditions (pH 5.0, 7.0, and 9.0; oxygen 0.2 and 6.2 mg/L). Under AMP and Cu(II) molar ratio of 1:1, AMP degradation was the fastest at pH 9.0, followed by pH 5.0 and pH 7.0. The facilitation of oxygen on AMP degradation was notable at pH 5.0 and 7.0 rather than pH 9.0. AMP degradation rate increased from 21.8% in 0.2 mg/L O₂ solution to 85.9% in 6.2 mg/L O₂ solution at pH 7.0 after 4-h reaction. AMP oxidation was attributed to both oxygen-derived Cu(I)/Cu(II) cycle and intermediate reactive oxygen species (HO^. and O₂^.−). Several intermediate and final products in AMP degradation were firstly identified by LC-quadrupole time-of-flight-MS analysis. Phenylglycine primary amine on the AMP structure was the essential complexation site to proceed with the oxidation reaction. The oxidation of AMP preferentially occurred on the β-lactam structure. The inherent mechanisms related to pH and oxygen conditions were firstly investigated, which could enhance the understanding of both oxidation and hydrolysis mechanisms in AMP degradation. This study not only has an important implication in predicting β-lactam antibiotic transformation and fate in natural environment but also benefits the developing of strategies of antibiotic control to reduce the environmental risk.

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A meta-analysis of the association between Helicobacter pylori (H. pylori) infection and hyperemesis gravidarum

Abstract

Background

Hyperemesis gravidarum remains a common, distressing, and significant yet poorly understood disorder during pregnancy. The association between maternal Helicobacter pylori (H. pylori) infection and hyperemesis gravidarum has been increasingly recognized and investigated. This study thus aimed to provide an updated review and meta-analysis of the topic.

Methods

Using the search terms (H. pyloriOR Helicobacter ORHelicobacter pyloriOR infection) AND (pregnancy OR emesis OR hyperemesis gravidarum OR nausea OR vomiting), a preliminary search on the PubMed, Ovid, Web of Science, Google Scholar, and WanFang database yielded 372 papers published in English between January 1st, 1960 and June 1st, 2017.

Results

A total of 38 cross-sectional and case-control studies, with a total of 10 289 patients were eligible for review. Meta-analysis revealed a significant association between H. pylori infection and hyperemesis gravidarum during pregnancy, with a pooled odds ratio of 1.348 (95% CI: 1.156-1.539, P < .001). Subgroup analysis found that serologic and stool antigen tests were comparable methods of detecting H. pylori as they yielded similar odds ratios.

Limitations

Although the studies did not have high heterogeneity (I² = 28%), publication bias was observed, and interstudy discrepancies in the diagnostic criteria adopted for hyperemesis gravidarum limit the reliability of findings. Also, 15 of the included studies were from the same country (Turkey), which could limit the generalizability of current findings. The prevalence of H. pylori infection varies throughout the world, and there may also be pathogenic differences as most strains of H. pylori in East Asia carry the cytotoxin-associated gene A gene.

Conclusion

H. pylori infection was associated with an increased likelihood of hyperemesis gravidarum during pregnancy. Given the high prevalence of H. pylori infections worldwide, detecting H. pylori infection and the eradication of maternal H. pylori infection could be part of maternal hyperemesis gravidarum management. Further confirmation with robust longitudinal studies and mechanistic investigations are needed.

http://ift.tt/2josVNW

Macrolide use in the previous years is associated with failure to eradicate Helicobacter pylori with clarithromycin-containing regimens

Abstract

Background

There is some evidence that prior use of macrolide antibiotics is a useful predictor of the likelihood of standard triple therapy failure in Helicobacter pylori eradication. In this study, we have evaluated whether previous intake of macrolides correlates with failure to eradicate H. pylori using two different first-line clarithromycin-containing regimens.

Materials and Methods

Retrospective study of 212 patients with H. pylori infection treated with one of two first-line clarithromycin-containing regimens: 108 patients treated with triple therapy for 10 days and 104 patients treated with concomitant therapy for 10 days. The intake of macrolides (clarithromycin, azithromycin, and other macrolides) prior to the eradication therapy was obtained from the electronic medical record, which contains information regarding all the medication prescribed to the patients since the year 2004.

Results

One hundred of 212 patients (47.2%) had received at least one treatment with macrolides during the years prior to the eradication therapy. H. pylori eradication rates were significantly lower in patients with previous use compared to patients without previous use of macrolides, both with triple therapy (60.8% vs 92.9%; P < .0001) and with concomitant therapy (85.7% vs 98.2%; P = .024).

Conclusions

Previous use of macrolides correlates with a low H. pylori eradication rate with triple and concomitant clarithromycin-containing regimens. In addition, our study shows that in patients without previous use of macrolides, triple therapy achieves per-protocol eradication rates over 90%.

http://ift.tt/2AduHtl

Examining a staging model for anorexia nervosa: empirical exploration of a four stage model of severity

Abstract

Background

An illness staging model for anorexia nervosa (AN) has received increasing attention, but assessing the merits of this concept is dependent on empirically examining a model in clinical samples. Building on preliminary findings regarding the reliability and validity of the Clinician Administered Staging Instrument for Anorexia Nervosa (CASIAN), the current study explores operationalising CASIAN severity scores into stages and assesses their relationship with other clinical features.

Method

In women with DSM-IV-R AN and sub-threshold AN (all met AN criteria using DSM 5), receiver operating curve (ROC) analysis (n = 67) assessed the relationship between the sensitivity and specificity of each stage of the CASIAN. Thereafter chi-square and post-hoc adjusted residual analysis provided a preliminary assessment of the validity of the stages comparing the relationship between stage and treatment intensity and AN sub-types, and explored movement between stages after six months (Time 3) in a larger cohort (n = 171).

Results

The CASIAN significantly distinguished between milder stages of illness (Stage 1 and 2) versus more severe stages of illness (Stages 3 and 4), and approached statistical significance in distinguishing each of the four stages from one other. CASIAN Stages were significantly associated with treatment modality and primary diagnosis, and CASIAN Stage at Time 1 was significantly associated with Stage at 6 month follow-up.

Conclusions

Provisional support is provided for a staging model in AN. Larger studies with longer follow-up of cases are now needed to replicate and extend these findings and evaluate the overall utility of staging as well as optimal staging models.

http://ift.tt/2zHwE4g

Metallic glass-based chiral nanolattice: Light weight, auxeticity, and superior mechanical properties

Publication date: Available online 26 November 2017
Source:Materials Today
Author(s): Z.D. Sha, C.M. She, G.K. Xu, Q.X. Pei, Z.S. Liu, T.J. Wang, H.J. Gao
Metallic glasses (MGs) possess large elastic limit and high strength, but unfortunately they are of limited commercial utility due to their macroscopic brittle nature. Here, we report that a chiral nanolattice can be used to design large-scale MGs with negative Poisson's ratio, large elastic deformation capability, extensive hardening, and large ductility. Furthermore, the mechanical behaviors of the metallic glass chiral nanolattice (MGCN) can be significantly altered through changing the thickness and length of the ligaments in the nanolattice. An exceptional combination of high strength and ductility is observed for MGCN with thin and long ligaments, wherein the sample density is only twice that of water. The deformation mechanism that characterizes the chiral topology is a combination of rotation of the nodes with bending and extension of the ligaments, leading to the extraordinary mechanical behaviors. The present study not only offers a potential solution to mitigating the brittleness of MGs, but also provides some guidelines in designing large-scale MG meta-materials for prospective applications in the fields of acoustics and energy absorption.

Graphical abstract

http://ift.tt/2BeR4Ov

isGPT: An optimized model to identify sub-Golgi protein types using SVM and Random Forest based feature selection

Publication date: Available online 26 November 2017
Source:Artificial Intelligence in Medicine
Author(s): M. Saifur Rahman, Md. Khaledur Rahman, M. Kaykobad, M. Sohel Rahman
The Golgi Apparatus (GA) is a key organelle for protein synthesis within the eukaryotic cell. The main task of GA is to modify and sort proteins for transport throughout the cell. Proteins permeate through the GA on the ER (Endoplasmic Reticulum) facing side (cis side) and depart on the other side (trans side). Based on this phenomenon, we get two types of GA proteins, namely, cis-Golgi protein and trans-Golgi protein. Any dysfunction of GA proteins can result in congenital glycosylation disorders and some other forms of difficulties that may lead to neurodegenerative and inherited diseases like diabetes, cancer and cystic fibrosis. So, the exact classification of GA proteins may contribute to drug development which will further help in medication.In this paper, we focus on building a new computational model that not only introduces easy ways to extract features from protein sequences but also optimizes classification of trans-Golgi and cis-Golgi proteins. After feature extraction, we have employed Random Forest (RF) model to rank the features based on the importance score obtained from it. After selecting the top ranked features, we have applied Support Vector Machine (SVM) to classify the sub-Golgi proteins. We have trained regression model as well as classification model and found the former to be superior. The model shows improved performance over all previous methods. As the benchmark dataset is significantly imbalanced, we have applied Synthetic Minority Over-sampling Technique (SMOTE) to the dataset to make it balanced and have conducted experiments on both versions. Our method, namely, identification of sub-Golgi Protein Types (isGPT), achieves accuracy values of 95.4%, 95.9% and 95.3% for 10-fold cross-validation test, jackknife test and independent test respectively. According to different performance metrics, isGPT performs better than state-of-the-art techniques. The source code of isGPT, along with relevant dataset and detailed experimental results, can be found at http://ift.tt/2A8tLc6.



http://ift.tt/2AzAoEY

Adsorption of cesium ion by marine actinobacterium Nocardiopsis sp. 13H and their extracellular polymeric substances (EPS) role in bioremediation

Abstract

This paper evaluates the cesium adsorption of marine actinobacterium Nocardiposis sp. 13H strain isolated from nuclear power plant sites in India. It could remove 88.6 ± 0.72% of Cs⁺ from test solution containing 10 mM CsCl₂. The biosorption of Cs⁺ with different environmental factors such as pH, temperature, and time interval is also determined. Scanning electron microscopy coupled with energy dispersive spectroscopy (EDS) confirmed the Cs⁺ adsorption by Nocardiopsis sp. 13H. Most of the bound cesium was found to be associated extracellular polymeric substances (EPS) suggesting its interaction with the surface active groups. The main component of the EPS was carbohydrate followed by protein and nucleic acid. Further, Fourier transform infrared (FTIR) spectroscopy suggested the carboxyl, hydroxyl, and amide groups on the strain cell surface were likely to be involved in Cs⁺ adsorption. Results from this study show Nocardiopsis sp. 13H microorganism could be useful in exploring the biosorption of radioisotope pollution and developing efficient and eco-friendly biosorbent for environmental cleanup.

http://ift.tt/2A9B0A4

Study on the influential biochemical indices of Cd(II) on Eisenia fetida in oxidative stress by principal component analysis in the natural soil

Abstract

With the aggravation of heavy metal pollution in soil, the individual heavy metal content monitoring cannot predict the true effects of harmful substances on the ecosystems. Thus, the effective biological evaluation system should be established to assess the pollution risk caused by heavy metal. Earthworms are widely distributed in the soil, and at the bottom of the food chain, the changes of biochemical indices play an important role in the early warning for heavy metal pollution. Principal component analysis (PCA) is a statistical method that derives several independent principal components from the original variable based on retaining the information as much as possible. This paper is aimed at finding out and analyzing the key monitoring factors related to Cd²⁺ on the earthworm Eisenia fetida in oxidative stress. The Cd²⁺ stress concentrations were set at 0, 1, 10, 20, 100, 200, 400, and 800 mg kg⁻¹, and the post-clitellum segment of earthworm was chosen to determine TP, POD, SOD, GST, GPX, CAT, MDA, VE, and AChE. The results showed that the main bioindicators associated with oxidative stress reaction were GST, POD, and MDA at the exposure time of 10 days; at 20 days GPX, MDA, and AChE; at 30 days CAT, TP, and GPX; CAT, MDA, and SOD at 40th day. These results indicated that PCA can quickly, effectively, directly, and scientifically select biomarkers of oxidative stress induced by Cd and improve the accuracy and scientificity of earthworm as a biomarker in monitoring and early warning for heavy metal-contaminated soil.

http://ift.tt/2hX7Qtv

Spatiotemporal variation and exposure risk to human health of potential toxic elements in suburban vegetable soils of a megacity, SW China, 2012–2016

Abstract

Trace element contamination in soils of vegetable fields can threat public health. Seven potential toxic elements (As, Cd, Cr, Cu, Ni, Pb, and Zn) in suburban vegetable soils of Chengdu city, Southwest China, in 2012 and 2016, were analyzed to identify their sources with the spatiotemporal variation and assess their contamination and health risk for residents. The results showed that the concentrations of soil elements did not increase significantly in 2016 compared with that in 2012, whereas their spatial distributions altered markedly. The hot spots of soil As, Cd, and Pb as well as Cu and Zn in 2016 revealed the anthropogenic sources including agricultural activities, industrial emissions, road dust with heavy traffic, and open burning of solid waste. The apparent spatial difference of anthropogenic elements was related to the layout of land use surrounding the vegetable field. The contamination of soil elements decreased in the order of Cd > As ≈ Zn > Cu ≈ Pb > Cr ≈ Ni in 2012 and Cd > Zn > As ≈ Cu ≈ Pb > Cr ≈ Ni in 2016, and the vegetable soils were slightly to moderately contaminated by these elements through integrated contamination index. The sites affected by the trace elements did not increase in 2016 than in 2012, whereas the sites with relatively high contamination increased markedly. The non-carcinogenic risk of trace elements was generally acceptable, and children showed higher health risk than adults. The As carcinogenic risk for children varied between 5.48 × 10⁻⁵ and 1.59 × 10⁻⁴ in 2012 and between 4.40 × 10⁻⁵ and 1.82 × 10⁻⁴ in 2016, and the sites above acceptable levels (> 10⁻⁴) reached 60.6% and 48.5% in 2012 and 2016, respectively. The health risk of As in the vegetable soils should be paid more attention due to its high toxicity.

http://ift.tt/2i9yeo3

A critical approach to the toxic metal ion removal by hazelnut and almond shells

Abstract

The adsorption capacity of ground hazelnut (HS) and almond (AS) shells towards Pb(II) and Cd(II) has been studied at pH = 5, in NaNO₃ and NaCl ionic media, in the ionic strength range 0.05–0.5 mol L⁻¹. Kinetic and equilibrium experiments were carried out by using the Differential Pulse Anodic Stripping Voltammetry technique to check the amount of the metal ion removed by HS and AS materials. Different kinetic and equilibrium equations were used to fit experimental data and a statistical study was done to establish the suitable model for the data fitting. A speciation study of the metal ions in solution was also done in order to evaluate the influence of the ionic medium on the adsorption process. TGA-DSC, FT-IR, and SEM-EDX techniques were used to characterize the adsorbent materials. The mechanism of metal ions adsorption was explained on the basis of the results obtained by the metal ions speciation study and the characterization of materials.

http://ift.tt/2k0UyAH

Neural mechanisms of movement planning: motor cortex and beyond

Publication date: April 2018
Source:Current Opinion in Neurobiology, Volume 49
Author(s): Karel Svoboda, Nuo Li
Neurons in motor cortex and connected brain regions fire in anticipation of specific movements, long before movement occurs. This neural activity reflects internal processes by which the brain plans and executes volitional movements. The study of motor planning offers an opportunity to understand how the structure and dynamics of neural circuits support persistent internal states and how these states influence behavior. Recent advances in large-scale neural recordings are beginning to decipher the relationship of the dynamics of populations of neurons during motor planning and movements. New behavioral tasks in rodents, together with quantified perturbations, link dynamics in specific nodes of neural circuits to behavior. These studies reveal a neural network distributed across multiple brain regions that collectively supports motor planning. We review recent advances and highlight areas where further work is needed to achieve a deeper understanding of the mechanisms underlying motor planning and related cognitive processes.



http://ift.tt/2zGCFy4

Decision-making behaviors: weighing ethology, complexity, and sensorimotor compatibility

Publication date: April 2018
Source:Current Opinion in Neurobiology, Volume 49
Author(s): Ashley L Juavinett, Jeffrey C Erlich, Anne K Churchland
Rodent decision-making research aims to uncover the neural circuitry underlying the ability to evaluate alternatives and select appropriate actions. Designing behavioral paradigms that provide a solid foundation to ask questions about decision-making computations and mechanisms is a difficult and often underestimated challenge. Here, we propose three dimensions on which we can consider rodent decision-making tasks: ethological validity, task complexity, and stimulus-response compatibility. We review recent research through this lens, and provide practical guidance for researchers in the decision-making field.



http://ift.tt/2n6Txbq

Aging Schwann cells: mechanisms, implications, future directions

Publication date: December 2017
Source:Current Opinion in Neurobiology, Volume 47
Author(s): Michio Wendell Painter
The aging peripheral nervous system (PNS) is prone to a number of disorders, including the development of neuropathies and increased regenerative failure. Although the basic mechanisms of the aging PNS are still rather murky, recent work has revealed that 'old' Schwann cells acquire a number of dysfunctions in mammals. This review will assess our current knowledge about aging Schwann cells while emphasizing where gaps exist. Indeed, as our understanding of how these peripheral glia contribute to the development, maintenance and regeneration of the PNS becomes increasingly refined, we should also turn our attention to questions of escalating importance in our rapidly greying society: how do Schwann cells change with aging, how might these changes contribute to dysfunction and disease, and what, if anything, might this tell us about the aging central nervous system?



http://ift.tt/2zH82sa

Myelin dynamics: protecting and shaping neuronal functions

Publication date: December 2017
Source:Current Opinion in Neurobiology, Volume 47
Author(s): Aiman S Saab, Klaus-Armin Nave
Myelinating glial cells are well-known to insulate axons and to speed up action potential propagation. Through adjustments in the axonal coverage with myelin, myelin sheath thickness and possibly nodal/internode length oligodendrocytes are involved in fine-tuning the brain's computational power throughout life. Be it motor skill learning or social behaviors in higher vertebrates, proper myelination is critical in shaping brain functions. Neurons rely on their myelinating partners not only for setting conduction speed, but also for regulating the ionic environment and fueling their energy demands with metabolites. Also, long-term axonal integrity and neuronal survival are maintained by oligodendrocytes and loss of this well-coordinated axon–glial interplay contributes to neuropsychiatric diseases. Better insight into how myelination and oligodendrocyte functions are constantly fine-tuned in the adult CNS, which includes sensing of neuronal activity and adjusting glial metabolic support, will be critical for understanding higher brain functions and cognitive decline associated with myelin abnormalities in the aging brain.



http://ift.tt/2n6Tuwg

Lateral habenula in the pathophysiology of depression

Publication date: February 2018
Source:Current Opinion in Neurobiology, Volume 48
Author(s): Yan Yang, Hao Wang, Ji Hu, Hailan Hu
Depression is a devastating disorder with a combination of diverse symptoms such as low self-esteem, lack of motivation, anhedonia, loss of appetite, low energy, and discomfort without a clear cause. Depression has been suggested to be the result of maladaptive changes in specific brain circuits. Recently, the lateral habenula (LHb) has emerged as a key brain region in the pathophysiology of depression. Increasing evidence from rodent, non-human primate and human studies indicates that the aberrant activity of the LHb is associated with depressive symptoms such as helplessness, anhedonia, and excessive negative focus. Revealing the molecular, cellular and circuit properties of the LHb will help explain how abnormalities in LHb activity are linked to depressive disorders, and shed light on developing novel strategies for depression treatment.



http://ift.tt/2zH7YbU

Specification, plasticity and evolutionary origin of peripheral glial cells

Publication date: December 2017
Source:Current Opinion in Neurobiology, Volume 47
Author(s): Maria Eleni Kastriti, Igor Adameyko
Peripheral glia includes predominantly myelinating and non-myelinating Schwann cells in addition to satellite, terminal and enteric glia as well as other unresolved subtypes with localized functions. Of these subtypes, all of them originate from neural crest-derived embryonic Schwann cell precursors (SCPs). Specific gene regulatory networks control neural crest specification and downstream events, including SCP differentiation and myelination. Embryonic SCPs are multipotent and generate neuroendocrine cells, parasympathetic and enteric neurons, melanocytes and other cell types. The evolutionary origin of peripheral Schwann cell lineage is not widely discussed in the literature, despite numerous similarities between central and peripheral glia. Here, we review the major features of the Schwann cell lineage and proceed to an evolutionary discussion around possible relations between central and peripheral glial cells.



http://ift.tt/2n6TrAA

Boundary cap cells in development and disease

Publication date: December 2017
Source:Current Opinion in Neurobiology, Volume 47
Author(s): Katarzyna J .Radomska, Piotr Topilko
Broad plasticity of the peripheral glia is an emerging concept during development of the peripheral nervous system (PNS). Recent studies have identified the neural crest-derived boundary caps (BCs), as a multitask stem cell population of the developing PNS. BC progeny migrate along the nerves to provide the major glial component of nerve roots and nerve terminals in the skin. Strikingly, those two locations constitute the privileged sites for development of benign peripheral nerve sheath tumors called neurofibromas in patients with neurofibromatosis type 1 (NF1), making BCs attractive candidates for the 'cell of origin' of this disease. Here, we review these exciting findings, focusing on the origin and novel functions of BCs. We further discuss the heterogeneity of BCs, and address their implication in the pathogenesis of NF1.



http://ift.tt/2zGCym8

A numerical study on the influence of composite wrinkle defect geometry on compressive strength

Publication date: 15 February 2018
Source:Materials & Design, Volume 140
Author(s): Ningbo Xie, Robert A. Smith, Supratik Mukhopadhyay, Stephen R. Hallett
Out-of-plane winkling in continuous-fibre reinforced composites has a significant influence on compressive failure stress, which needs to be considered and evaluated during the design, manufacture and inspection stages, to achieve high-performance composite components. With the development of a three-dimensional characterisation based on non-destructive testing methods and finite-element modelling, it is possible to combine the two techniques to give a prediction of mechanical performance using directly measured geometry. This paper uses a new methodology developed for combining non-destructive characterisation and numerical analysis techniques to automatically create a series of models with controlled wrinkle geometry. It has been possible to determine the dependence of compressive strength on various wrinkle-severity and wrinkle-extent parameters. The outcome shows a dominant dependence on the maximum wrinkle angle in the load direction, with an additional dependence on the wrinkle wavelength for larger wrinkle angles. In terms of the extent of the wrinkled region, the strength reduces as the wrinkle extent in the load direction becomes concentrated locally or the wrinkled proportion of the cross-sectional area (perpendicular to the load) increases.

Graphical abstract

http://ift.tt/2zGiQHh

Gyroid porous titanium structures: A versatile solution to be used as scaffolds in bone defect reconstruction

Publication date: 15 February 2018
Source:Materials & Design, Volume 140
Author(s): A. Yánez, A. Cuadrado, O. Martel, H. Afonso, D. Monopoli
Triply periodic minimal surfaces (TPMS) have emerged as a suitable tool for designing porous biomaterials. One of the well-known TPMS structures is the gyroid structure. Different types of gyroid porous structures (normal and deformed gyroid structures) with different porosities have been designed and fabricated by Electron Beam Melting technology with the purpose of analysing the mechanical properties under compression and torsion loads. Then, some of them have also been studied by finite element method for different load directions. The compression tests demonstrated that the deformed gyroids presented high stiffness and strength with loads in the longitudinal direction of the structures, especially when the deformed gyroids were reinforced with a shell. The torsion tests showed that the normal gyroids presented better torsional stiffness and strength than the deformed gyroids, with high CAD porosities (90%). However, no significant differences between both structures were found for low CAD porosities (75%). Finite element analysis showed that when the loads adopted a 45° angle with regard to the longitudinal axis of the structure, the normal gyroids presented more homogeneous behaviour than the deformed gyroids. In summary, gyroid porous titanium structures presented good and versatile stiffness and strength to be used for correction of bone defects.

Graphical abstract

http://ift.tt/2zGuOAA

Facile preparation of mechanically durable, self-healing and multifunctional superhydrophobic surfaces on solid wood

Publication date: 15 February 2018
Source:Materials & Design, Volume 140
Author(s): Kunkun Tu, Xiaoqing Wang, Lizhuo Kong, Hao Guan
Maintaining the hierarchically roughened structures and non-wetting properties are critically essential for a superhydrophobic surface upon sunlight irradiation, physical rubbing or organic contamination in practical applications but remain extremely challenging. Herein, by simply spraying a waterborne perfluoroalkyl methacrylic copolymer (PMC) emulsion mixed with TiO2 nanoparticles onto polydimethylsiloxane (PDMS) pre-coated substrates, mechanically durable, self-healing superhydrophobic surfaces were fabricated on solid wood. The coated surfaces exhibited exceptional repellency toward water as well as organic liquids with low surface tensions including ethylene glycol. The as-prepared coatings on the rigid wood substrate showed excellent durability against mechanical abrasion while retaining the rough surface textures due to the hydrophobic binder PMC anchoring the nanoparticles tightly on the surface, thus sustaining the superhydrophobicity of the surface. Moreover, the non-wetting properties of the surface damaged by ultraviolet (UV) irradiation can be automatically restored by a simple heat treatment, which facilitates the migration of the underlying hydrophobic PDMS onto the surface replenishing the necessary low-surface-energy materials. Besides, the TiO2-containing coatings exhibited photocatalytic activity in degrading organic contaminants and can also preserve the underlying wood substrate from photodegradation during UV exposure. The developed method herein features environment-friendly raw materials, facile processing and large-scale fabrication. Such superhydrophobic wood surfaces with multi-functionalities may open new avenues in the field of novel wood-based materials.

Graphical abstract

http://ift.tt/2zGuMIY

Widespread Erythematous and Bullous Plaques Associated With Nasolabial Fold Ulceration

No abstract available

http://ift.tt/2BeR6G5

What are the costs involved with a hair transplant?

In this article, we look at how hair transplants work and how much they tend to cost. We also examine other considerations and options for hair loss.

http://ift.tt/2BooNFV

Dietary patterns in Mexican children and adolescents: Characterization and relation with socioeconomic and home environment factors

Publication date: 1 February 2018
Source:Appetite, Volume 121
Author(s): Marcia Galvan-Portillo, Emanny Sánchez, Luz Mery Cárdenas-Cárdenas, Roberto Karam, Luz Claudio, Miguel Cruz, Ana I. Burguete-García
BackgroundEating habits in children and adolescents are influenced by multiple determinants, which include socioeconomic and home environmental factors.ObjectiveTo characterize the dietary patterns in Mexican children and adolescents and to assess its association with socioeconomic and home environmental factors.MethodsA cross-sectional study was conducted in 878 children and adolescents aged 5–15 years, unrelated, selected randomly from Morelos Sports Unit at north of Mexico City. Dietary, anthropometric, family, and socioeconomic information was obtained from each participant. Dietary patterns were identified through cluster analysis. The association between dietary patterns with socioeconomic and home environmental factors was assessed by a multivariate multinomial logistic regression model.ResultsThree major dietary patterns were identified: diverse dietary pattern (D), high fat dietary pattern (HF), and high sugar dietary pattern (HS). 87% of the participants followed the HF or HS dietary patterns (36% & 51%, respectively). Mother's occupation and the child's screen time was associated with a significant likelihood of following a HF and HS dietary patterns.ConclusionA high percentage of children and adolescents reported following a HS or HF dietary pattern, which in turn were associated with socioeconomic and home environmental factors. These results suggests priority groups for prevention and control actions.



http://ift.tt/2n5xK3K

Image processing and Quality Control for the first 10,000 brain imaging datasets from UK Biobank

Publication date: 1 February 2018
Source:NeuroImage, Volume 166
Author(s): Fidel Alfaro-Almagro, Mark Jenkinson, Neal K. Bangerter, Jesper L.R. Andersson, Ludovica Griffanti, Gwenaëlle Douaud, Stamatios N. Sotiropoulos, Saad Jbabdi, Moises Hernandez-Fernandez, Emmanuel Vallee, Diego Vidaurre, Matthew Webster, Paul McCarthy, Christopher Rorden, Alessandro Daducci, Daniel C. Alexander, Hui Zhang, Iulius Dragonu, Paul M. Matthews, Karla L. Miller, Stephen M. Smith
UK Biobank is a large-scale prospective epidemiological study with all data accessible to researchers worldwide. It is currently in the process of bringing back 100,000 of the original participants for brain, heart and body MRI, carotid ultrasound and low-dose bone/fat x-ray. The brain imaging component covers 6 modalities (T1, T2 FLAIR, susceptibility weighted MRI, Resting fMRI, Task fMRI and Diffusion MRI). Raw and processed data from the first 10,000 imaged subjects has recently been released for general research access. To help convert this data into useful summary information we have developed an automated processing and QC (Quality Control) pipeline that is available for use by other researchers. In this paper we describe the pipeline in detail, following a brief overview of UK Biobank brain imaging and the acquisition protocol. We also describe several quantitative investigations carried out as part of the development of both the imaging protocol and the processing pipeline.



http://ift.tt/2k1hvn6

ZBP1: Innate Sensor Regulating Cell Death and Inflammation

Publication date: Available online 25 November 2017
Source:Trends in Immunology
Author(s): Teneema Kuriakose, Thirumala-Devi Kanneganti
Z-DNA-binding protein 1 (ZBP1), initially reported as an interferon (IFN)-inducible tumor-associated protein, harbors nucleic acid-binding domains for left-handed helix (Z-form) and receptor-interacting protein homotypic interaction motif (RHIM) domains for protein homotypic interactions. Recent studies have identified ZBP1 as an innate sensor of viral infections and a target of viral evasion strategies, regulating cell death, inflammasome activation, and proinflammatory responses. ZBP1 also functions during development and can trigger perinatal lethality when its RHIM-dependent interactions are not restricted. Here we review the history and emergence of ZBP1 as a pathogen sensor and a central regulator of cell death and inflammatory responses. We also discuss the gaps in our knowledge regarding the regulation and functions of ZBP1 and highlight potential avenues for future research.



http://ift.tt/2zosOJ0

Letter from the Guest Editor

Publication date: Available online 21 November 2017
Source:Seminars in Ultrasound, CT and MRI
Author(s): Gopal R. Vijayaraghavan




http://ift.tt/2zCgqJt

Diffuse Liver Diseases: Role of imaging

Publication date: Available online 20 November 2017
Source:Seminars in Ultrasound, CT and MRI
Author(s): Adele Taibbi, Dario Picone, Massimo Midiri, Ludovico La Grutta, Tommaso Vincenzo Bartolotta
Nowadays the most common imaging techniques allow to study focal liver lesions with high diagnostic accuracy but a relatively recent emerging field of interest is represented by diffuse liver disease. They include a variegated series of storage and metabolic pathologies (i.e. iron overload disorders and steatosis) requiring a precise diagnosis not always possible at imaging due to the overlapping of findings at conventional ultrasound, CT or MR studies.In recent years several imaging tecniques and specific softwares have been developed, especially for ultrasound and MR imaging, in order to identify different parameters useful in the noninvasive recognition and follow-up of these diffusely processes diffusely involving the liver.The aim of this review is to describe the most common and useful imaging findings of the most common and uncommon diffuse liver diseases illustrating the newest imaging technologies and developments at our disposal with corresponding advantages, limitations and pitfalls.



http://ift.tt/2n450bR

CT Imaging of Emergent Renal Conditions

Publication date: Available online 24 November 2017
Source:Seminars in Ultrasound, CT and MRI
Author(s): Kunal Kothari, John J. Hines
The kidneys are paired intra-abdominal organs which provide essential functions and maintain homeostasis throughout the human body. Numerous disease processes affect the kidneys and cause acute renal dysfunction or other potentially catastrophic complications. These conditions can be broadly categorized into obstructive, infectious, hemorrhagic, traumatic and vascular diseases. Imaging plays a vital role in the work-up and diagnosis of acute and emergent renal conditions. Evaluation of emergent renal conditions with a focus on CT imaging are discussed.



http://ift.tt/2zEKOmJ