Detoxification of U(VI) by Paecilomyces catenlannulatus investigated by batch, XANES and EXAFS techniques

Publication date: September 2018
Source:Journal of Environmental Radioactivity, Volume 189
Author(s): Fengbo Li, Xiaoyu Li, Pu Cui
Paecilomyces catenlannulatus (P. catenlannulatus) as a genus of entomogenous fungus presented a variety of surface reactive groups by batch characterizations. The detoxification of U(VI) by P. catenlannulatus was investigated under different water chemistry (pH, incubation time, foreign anions and U(VI) concentration) by batch techniques. Approximately 75% of U(VI) was reduced to U(IV) (i.e., U^(IV)O2(s)) by P. catenlannulatus at pH 5.5 and 7 days under glovebox conditions, therefore the formation of precipitates decreased the toxicity of U(VI) for P. catenlannulatus. In addition, phosphate facilitate the U(VI) reduction, whereas carbonate and sulfate inhibited the U(VI) reduction. The activities of catalase (CAT), superoxide dismutase (SOD) and glutathione (GSH) level were stimulated exposure to 1-30 mg/L U(VI), indicating that CAT, SOD and GSH were antagonized for the oxidant stress derived from U(VI) at low concentrations. According to XPS and XANES analysis, the occurrence of U(IV) revealed the reduction of adsorbed U(VI) to U(IV) by P. catenlannulatus. The results of EXAFS analysis indicated that the fitting of U-O and U-U shell for U-loaded P. catenlannulatus was similar to that of U^(IV)O2(s)). The formation of U-bearing precipitates decreased the toxicity of U(VI) for P. catenlannulatus. These findings indicated that P. catenlannulatus is capable to detoxify U(VI) by extracellar/intracellar defense systems. Therefore, P. catenlannulatus can be utilized as a promising bioadsorbents for remediation of uranium-contaminated wastewater in environmental cleanup.



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Functional film by trigger-free self-assembly of adhesive soft microgels at skin temperature

Publication date: 5 June 2018
Source:Materials & Design, Volume 147
Author(s): Mohamed Boularas, Sadia Radji, Emilie Gombart, Jean-François Tranchant, Valérie Alard, Laurent Billon
Trigger-free self-assembly of oligo(ethylene glycol) OEG-based responsive microgels is for the first time described via simple solvent evaporation process at skin temperature and ambient pressure. This unique behaviour is attributed to the intrensic OEG microgel structure and properties due to a negative glass transition temperature, a high adhesion energy, an elastic mechanical property and a high interpenetration of microgels, combined in an all-in-one building block. Furthermore, the encapsulation of magnetic nanoparticles (NPs) into the OEG-based microgels introduced interferential photonic and magnetic properties to the films. These microgels exhibiting simultaneously spontaneous film-forming and colored photonic properties open up the development of a unique easy-to-handle material for cosmetic applications, but also smart patches for healthcare or medicine.

Graphical abstract

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Preparation of thermochromic liquid crystal microcapsules for intelligent functional fiber

Publication date: 5 June 2018
Source:Materials & Design, Volume 147
Author(s): Yu Guan, Liping Zhang, Dong Wang, John L. West, Shaohai Fu
Cholesteric liquid crystals microcapsules (CLCM) were prepared via complex coacervation method, which were further used as thermochromic materials in an intelligent functional fiber. The morphology of CLCM with core-shell structure was confirmed by SEM and TEM images. According to the TG results, CLC core took 52wt% of the microcapsules. Thermochromic property of the CLCM was closely related to its particle size, and CLCM in the range of 3–30μm had excellent thermochromic property producing color progressively moving from red to blue as the temperature was raised. The CLCM were added to polyvinyl pyrrolidone (PVP) solution and CLCM/PVP fibers were prepared by electrospinning method. The thermochromic performance of CLCM/PVP fibers was in accordance with CLCM, and the optimal particle size of CLCM for preparing CLCM/PVP fibers was 3–10μm.

Graphical abstract

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Impact of economic growth, nonrenewable and renewable energy consumption, and urbanization on carbon emissions in Sub-Saharan Africa

Abstract

The present study explores the impact of economic growth; urban expansion; and consumption of fossil fuels, solid fuels, and renewable energy on environmental degradation in developing economies of Sub-Saharan Africa. To demonstrate its findings in detail, the study adopts a system generalized method of moment (GMM) on a panel of 34 emerging economies for the period from 1995 to 2015. The results describe that the consumption of fossil and solid fuels for cooking and expansion of urban areas are significantly contributing to carbon dioxide emissions, on one end, and stimulating air pollution, on the other. The results also exhibit an inverted U-shape relationship between per capita economic growth and carbon emissions. This relation confirms the existence of an environmental Kuznets curve (EKC) in middle- and low-income economies of Sub-Saharan Africa. Furthermore, the findings reveal that the use of renewable energy alternatives improves air quality by controlling carbon emissions and lowering the direct interaction of households with toxic gases. Thus, the use of renewable energy alternatives helps the economies to achieve sustainable development targets.

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Investigating the role of urban development in the conventional environmental Kuznets curve: evidence from the globe

Abstract

We investigated the role of urbanization in the conventional environmental Kuznets curve (EKC) of the globe. The overall population and rural population were also considered for control purposes. Based on our findings, we suggest that the conventional EKC of the globe is not an inverted U-shape but becomes downward sloping when urban development is added and inverted U-shapes when the overall population and rural population volumes are added.

http://ift.tt/2G29dVE

Risk assessment by percolation leaching tests of extensive green roofs with fine fraction of mixed recycled aggregates from construction and demolition waste

Abstract

Extensive green roofs are urban construction systems that provide thermal regulation and sound proofing for the buildings involved, in addition to providing an urban heat island mitigation or water retention. On the other hand, policies towards reduction of energy consumption, a circular economy and sustainability are core in the European Union. Motivated by this, an experimental study was carried out to evaluate the environmental risk assessment according to release levels of polluting elements on leachates of different green roof substrate mixtures based on recycled aggregates from construction and demolition waste through (i) the performance in laboratory of two procedures: compliance and percolation tests and (ii) an upscaled experimental leaching test for long-term on-site prediction. Four plots were built on a building roof and covered with autochthonous Mediterranean plants in Córdoba, South of Spain. As growing substrate, four mixtures were used of a commercial growing substrate with different proportions of a fine mixed recycled aggregate ranging from 0 to 75% by volume. The results show that these mixtures were classified as non-hazardous materials according to legal limits of the Landfill Directive 2003/33/CE. The release levels registered in extensive green roofs were lower compared to the laboratory test data. This shows how laboratory conditions can overestimate the potential pollutant effect of these materials compared to actual conditions.

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Heavy metal bioaccessibility and health risks in the contaminated soil of an abandoned, small-scale lead and zinc mine

Abstract

The lack of management in small-scale mining operations has the potential for negative repercussions, e.g., mine collapses, compared with well-regulated large-scale mines. Here, we used an in vitro model to investigate heavy metal soil pollution characteristics and their attendant health risks in an abandoned, small-scale lead (Pb) and zinc (Zn) mine located in southwestern China that had suffered from collapse. Our results showed the following: (1) Even the mine had been closed for many years, the soil was still heavily polluted by Pb, cadmium (Cd), and Zn, and there is a risk of secondary pollution. Pb, Zn, and Cd concentrations in the mining areas were all approximately 22–42 times higher than the background soil levels of Guangxi Province. (2) Cd had the largest bioaccessibility, and mining areas tend to have soils containing more bioaccessible metals (78 ± 14%, 27 ± 4%, and 38 ± 12% for Cd, Pb, and Zn in gastric phase and 40 ± 12%, 10 ± 5%, and 19 ± 8% in intestinal phase correspondingly). (3) Results of a stepwise, multiple regression analysis revealed that the total soil content of the three metals (Pb, Zn, and Cd), TOC (total organic carbon), soil composition, and Mn content were the main impact factors for the Pb, Cd, and Zn soil bioaccessibility in study area (R² = 0.37~0.93). (4) A health risk assessment based on Pb, Cd, and Zn bioaccessibility indicated that the health risk for people in mine area is not high (HI is 1.07 at most and CR 2.40E−6 at most for children).

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Contribution of root uptake to cadmium accumulation in two peanut cultivars: evidence from a split-column soil experiment

Abstract

Cadmium (Cd) accumulation and internal Cd translocation in the peanut (Arachis hypogaea L.) are highly related to root uptake, which may largely depend on the cultivar variation and the depth of the Cd-contaminated soil. A split-column soil experiment was conducted using two common Chinese peanut cultivars (Huayu-20 and Huayu-23) known to relocate Cd to different tissues. The growth medium was separated into four layers and Cd solution was solely applied to one layer to determine the key depth affecting the Cd accumulation in a plant via root uptakes. The results showed that the biomass of Huayu-23 was significantly higher biomass (3.28–94.0%) than that of Huayu-20, especially in the aerial parts (stems and leaves) and kernels, implying the dilution of Cd. Following the addition of Cd to the soil, the Cd concentrations in peanut tissues increased on average by 28.9–172 and 28.3–111% in Huayu-20 and Huayu-23, respectively. The largest presence of Cd in a peanut plant was observed in the aerial parts, followed by the kernels. Huayu-20 accumulated more Cd in plant tissues than did Huayu-23 due to the former's high Cd translocation. These findings imply that peanut cultivars vary widely in biomass, Cd accumulation, and the percentage distribution of Cd among various plant tissues, especially kernels. Different Cd treatments in the full depth of the root zone induced significant alterations in Cd accumulation of peanut tissues, especially kernels, for both cultivars. The percentage distribution of Cd accumulation by kernels was significantly higher in the deeper layer than in the top layer of the root zone for both peanut cultivars. This study suggests that soil modifications performed during agronomic activities should take into account the full depth of root exploration as well as the peanut cultivars to manage plant Cd uptake.

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Clinical Thyroidology®for the Public – Highlighted Article

From Clinical Thyroidology^® for the Public:  In 1–2% of PET scans performed for the diagnosis or staging of non-thyroid cancers, incidental uptake of a thyroid lesion is detected. Read More….

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Neurocognitive Basis of Racial Ingroup Bias in Empathy

Publication date: Available online 18 March 2018
Source:Trends in Cognitive Sciences
Author(s): Shihui Han
Racial discrimination in social behavior, although disapproved of by many contemporary cultures, has been widely reported. Because empathy plays a key functional role in social behavior, brain imaging researchers have extensively investigated the neurocognitive underpinnings of racial ingroup bias in empathy. This research has revealed consistent evidence for increased neural responses to the perceived pain of same-race compared with other-race individuals in multiple brain regions and across multiple time-windows. Researchers have also examined neurocognitive, sociocultural, and environmental influences on racial ingroup bias in empathic neural responses, as well as explored possible interventions to reduce racial ingroup bias in empathic brain activity. These findings have important implications for understanding racial ingroup favoritism in social behavior and for improving interracial communication.



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Durable response of early-stage breast cancer to bilateral definitive SBRT in a medically inoperable patient

Publication date: Available online 18 March 2018
Source:Practical Radiation Oncology
Author(s): Robert W. Gao, Sean S. Park, James W. Jakub, Tina J. Hieken, Amy L. Conners, Lonzetta Neal, Sandhya Pruthi, Kimberly S. Corbin, Elizabeth S. Yan, Robert W. Mutter, Bradley J. Stish




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In vivo response to a low-modulus PMMA bone cement in an ovine model

Publication date: Available online 17 March 2018
Source:Acta Biomaterialia
Author(s): C. Robo, G. Hulsart-Billström, M. Nilsson, C. Persson
Poly(methyl methacrylate) (PMMA) is the most commonly used material for the treatment of osteoporosis-induced vertebral compression fractures. However, its high stiffness may introduce an increased risk of adjacent vertebral fractures post-surgery. One alternative in overcoming this concern is the use of additives. This presents its own challenge in maintaining an adequate biocompatibility when modifying the base cement. The aim of this study was to evaluate the in vivo biocompatibility of linoleic acid (LA)-modified acrylic bone cement using a large animal model for the first time, in order to further advance towards clinical use. A worst-case approach was used, choosing a slow-setting base cement. The in vitro monomer release from the cements was also assessed. Additional material characterization, including mechanical tests, are summarized in Appendix A. Unmodified and LA-modified cements were injected into a total of 56 bone defects created in the femur and humerus of sheep. Histopathologic and histomorphometric analysis indicated that LA-modified cement showed a harmless tissue response similar to that of the unmodified cement. Adjacent bone remodeling was observed microscopically 4 weeks after implantation, suggesting a normal healing process of the bone tissues surrounding the implant. LA-modified cement exhibited lower mechanical properties, with a reduction in the elastic modulus of up to 65%. The handling properties were slightly modified without negatively affecting the injectability of the base cement. LA-modified bone cement showed good biocompatibility as well as bone compliant mechanical properties and may therefore be a promising material for the treatment of osteoporotic vertebral fractures.

Graphical abstract

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Neuroprotective effect of Phosphocreatine on oxidative stress and mitochondrial dysfunction induced apoptosis in vitro and in vivo: Involvement of dual PI3K/Akt and Nrf2/HO-1 pathways

Publication date: Available online 17 March 2018
Source:Free Radical Biology and Medicine
Author(s): Hailong Li, Zhongyuan Tang, Peng Chu, Yanlin Song, Ying Yang, Bin Sun, Mengyue Niu, Eskandar Qaed, Abdullah Shopit, Guozhu Han, Xiaodong Ma, Jinyong Peng, Min Hu, Zeyao Tang
Methylglyoxal (MGO), an active metabolite of glucose, is observed in high levels in the tissues and blood of diabetic patients. Phosphocreatine (PCr), a high-energy phosphate compound, exhibits a range of pharmacological actions but little is well known of its neuroprotective action. The aim of the present study was to investigate the neuroprotective effects and the possible mechanisms of PCr. Diabetes is closely associated with neurodegenerative diseases, leading not only to the peripheral nervous system (PNS) and but also to central nervous system (CNS) damage. Therefore, we established two rat models of diabetes in vivo induced by MGO and streptozocin (STZ) respectively, while utilized differentiated PC-12 cells in vitro. Treatment of PC-12 cells with PCr markedly attenuated MGO-induced change of viability, apoptosis, accompanied by decreased levels of caspase-3, casapse-9 and Bcl-2/Bax protein ratio. Determination of cellular respiratory function was performed with intact PC-12 cells and homogenized hippocampal neuron tissue of rat. Reactive oxygen species (ROS) generation was assessed by membrane permeable fluorescent probe DCFH-DA. The expressions of Akt, Nrf2 and HO-1 were examined by Western blot. PCr pretreatment significantly reduced oxidative stress-induced high LDH, MDA level, and ROS production of PC-12 cells. PCr pretreatment also significantly decreased mitochondrial dysfunction in vitro and in vivo. In addition, PCr pretreatment increased the expression of p-Akt, Nrf2 and HO-1, and reduced the apoptosis. Moreover, the expression of Cleaved caspase3 was partially increased and the p-Akt, Nrf2 and HO-1 was partially reduced by a PI3K inhibitor (LY294002). While, compared with LY294002 groups, pre-treatment with PCr at the concentrations of 20mM significantly reduced the expression of Cleaved caspase3 and increased the expression of p-Akt, Nrf2 and HO-1. Molecular docking assay showed that PCr possessed powerful affinity towards to Akt with lower binding energy. In conclusion, the neuroprotective effects of PCr in vitro and in vivo rely on normalizing mitochondrial function and reducing oxidative stress via Akt mediated Nrf2/HO-1 pathway, suggesting that PCr may be a novel therapeutic candidate for the treatment of diabetes-associated neurodegenerative diseases.

Graphical abstract

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Visual Outcomes and Clinical Manifestations of Pediatric Optic Neuritis in Indian Population: An Institutional Study

Background: Optic neuritis in children is an uncommon disorder which usually occurs after a viral illness or vaccination and, less frequently, occurs as a manifestation of a demyelinating disorder. Pediatric optic neuritis usually is bilateral and presents with optic disc edema, recovers rapidly with steroid therapy, and generally has low conversion rate to multiple sclerosis or neuromyelitis optica spectrum disorder. We report the clinical features and treatment outcomes of pediatric optic neuritis in Indian population, for which little data are available. Methods: We reviewed the medical case records of patients with optic neuritis who were younger than 18 years, from 1999 to 2016. All patients were assessed and managed in the Neuro-Ophthalmology Department of Sankara Nethralaya, a unit of Medical Research Foundation and Pediatric Neurology Department of Kanchi Kamakoti—Childs Trust Hospital, Chennai, India. Results: One hundred seventeen eyes of 78 children with mean age of 11.84 (±4.58) years were identified. Forty-two (53.8%) were females and 36 (46.2%) were males. Thirty-nine patients (50%) had bilateral involvement and a similar number had unilateral involvement. Fifty-nine eyes (50.4%) had optic disc edema, 20 eyes (17.1%) had disc pallor, and 38 eyes (32.4%) had normal discs. Of 63 patients who had neuroimaging, 36 had MRI, and 27 underwent computed tomography. Eighty-four eyes (of 59 patients) received steroid therapy according to the protocol of the Optic Neuritis Treatment Trial (ONTT). Thirty-three eyes that were treated with other steroid protocols were excluded from the final visual outcome analyses. Sixty of the 84 eyes (72.3%) recovered visual acuity of 20/40 or better. Visual acuity improvement was statistically significant between initial and final visual acuity (logMAR) in our patients treated with the ONTT protocol (P ≤ 0.001). Conclusions: Our Indian pediatric population had good visual recovery after steroid treatment for optic neuritis. Profound loss of visual acuity on presentation and bilateral involvement were significantly associated with poor visual outcome. Address correspondence to Selvakumar Ambika, DO, DNB, Department of Neuro Ophthalmology, Sankara Nethralaya, A Unit of Medical Research Foundation, 18 College Road, Nungambakkam, Chennai 600 006, India; E-mail: drsa@snmail.org The authors report no conflicts of interest. © 2018 by North American Neuro-Ophthalmology Society

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Cerebrospinal Fluid Pressure Reduction Results in Dynamic Changes in Optic Nerve Angle on Magnetic Resonance Imaging

Background: Optic nerve sheath tortuosity is a previously reported, but incompletely characterized, finding in idiopathic intracranial hypertension (IIH). We hypothesized that optic nerve angle (ONA), as a quantitative measure of tortuosity, would change dynamically with cerebrospinal fluid (CSF) pressure status of patients with IIH immediately before and after lumbar puncture (LP). Methods: Consecutive patients with suspected IIH referred for MRI and diagnostic LP were prospectively enrolled in this single institution, institutional review board–approved study. Each patient underwent a pre-LP MRI, diagnostic LP with opening pressure (OP) and closing pressure (CP), and then post-LP MRI all within 1 session. Sagittal and axial ONAs were measured on multiplanar T2 SPACE images by 2 neuroradiologists on pre- and post-LP MRI. Effects of measured pressure and CSF volume removal on changes in ONA were analyzed as was interrater reliability for ONA measurement. Results: Ten patients with IIH were included {all female, median age 29 (interquartile range [IQR] 25–32)}. All patients had elevated OP (median 37, IQR 34–41 cm H2O), and significantly reduced CP (median 18, IQR 16–19 cm H2O, P

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Neuro-Ophthalmology in Turkey

No abstract available

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Evaluation of Vision-Related Quality of Life in Chinese Patients With Leber Hereditary Optic Neuropathy and the G11778A Mutation

Objective: To assess quality of life (QoL) measures in Chinese Leber hereditary optic neuropathy (LHON) patients with the G11778A mutation. Methods: Chinese LHON patients with the G11778A mutation were prospectively evaluated using the Visual Function Index (VF-14) at 6 months, 1 year, and 3 years after the involvement of the second eye. Patients who completed the VF-14 at all 3 follow-up time designations were included in the analysis. Results: Fifty-five patients met the inclusion criteria. The median age of patients when their vision was bilaterally affected was 16.3 years old (interquartile range: 13.9–18.3 years). In our patient cohort, 89.1% (n = 49) were male, and the ratio of males to females was 8.2:1. The median logMAR visual acuity was 2.0 (interquartile range: 1.0–2.6). The mean VF-14 scores of patients with LHON at 6-month, 1-year, and 3-year follow-ups were 18.0 ± 19.2 (range 0–85.4), 19.9 ± 20.0 (range 0–85.4), and 20.7 ± 20.2 (range 0–85.4), and the differences were statistically significant (P

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