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Micòl Mastrocicco, Nicolò Colombani, Elisa Soana, Fabio Vincenzi, Giuseppe Castaldelli
Nitrate and ammonium are common inorganic contaminants of anthropogenic origin in many shallow aquifers around the world, while nitrite is less common, but it is most harmful than nitrate and ammonium due to its high reactivity. This paper presents evidence of nitrite accumulation after intense rainfalls in soil samples collected in an agricultural field characterized by organic matter chronic depletion. Moreover, an intact core from the same site was also collected to perform an unsaturated column experiment (60 cm long and 20 cm outer diameter) mimicking heavy rainfalls (230 mm in 2 days)...
February 2, 2019: Science of the Total Environment
Clint Cameron, Lindsay B Hutley, Daniel A Friess
Mangrove forests are extremely productive, with rates of growth rivaling some terrestrial tropical rainforests. However, our understanding of the full suite of processes underpinning carbon exchange with the atmosphere and near shore-waters, the allocation of carbon in mangroves, and fluxes of non-CO2 greenhouse gases (GHGs) are limited to a handful of studies. This constrains the scientific basis from which to advocate for greater support for and investment in mangrove restoration and conservation. Improving understanding is urgently needed given the on-going landuse pressures mangrove forests face, particularly throughout much of Southeast Asia...
February 8, 2019: Science of the Total Environment
Kostas Komnitsas, Evangelos Petrakis, Georgios Bartzas, Vassiliki Karmali
Socio-economic data on nickel and cobalt show their importance throughout the entire metal value chain, from mining to end use, disposal and recycling. Thus, the extraction of both metals from primary and secondary raw materials as well as from wastes is currently considered strategically important for the industry and the society. In this paper heap leaching of Greek low-grade saprolitic laterites, with Ni content 0.97%, was investigated. The main parameters studied involved the strength of the H2 SO4 solution used (49 and 147 g L-1 ) and the effect of adding sodium sulfite (Na2 SO3 ) in the leaching medium...
January 30, 2019: Science of the Total Environment
Emma Saavedra, Rusely Encalada, Citlali Vázquez, Alfonso Olivos-García, Paul A M Michels, Rafael Moreno-Sánchez
Entamoeba histolytica has neither Krebs cycle nor oxidative phosphorylation activities; therefore, glycolysis is the main pathway for ATP supply and provision of carbon skeleton precursors for the synthesis of macromolecules. Glucose is metabolized through fermentative glycolysis, producing ethanol as its main end-product as well as some acetate. Amoebal glycolysis markedly differs from the typical Embden-Meyerhof-Parnas pathway present in human cells: (i) by the use of inorganic pyrophosphate, instead of ATP, as the high-energy phospho group donor; (ii) with one exception, the pathway enzymes can catalyze reversible reactions under physiological conditions; (iii) there is no allosteric regulation and sigmoidal kinetic behavior of key enzymes; and (iv) the presence of some glycolytic and fermentation enzymes similar to those of anaerobic bacteria...
February 14, 2019: Molecular and Biochemical Parasitology
Qingguo Song, Kailou Zhao, Hongjun Xia, Jiawei Liu, Quan Bai
A novel silica-based reversed-phase/weak anion-exchange mixed-mode chromatography (MMC) stationary phase referred to as OTAS was synthesized based on the horizontal polar-copolymerized approach using trichlorooctadecylsilane (ODS) and (3-glycidyloxypropyl)trimethoxysilane (GPS) as ligands, and then followed by the reaction of epoxy group with diethylamine to introduce the tertiary ammonium functional group. The new stationary phase was characterized by instrumental analysis, and evaluated by separating the mixture of alkylbenzene homologues in reversed-phase mode and acidic organic compounds in ion-exchange chromatography mode, respectively...
May 15, 2019: Talanta
Zhanqiang Yang, Zongying Li, Feifang Zhang, Bingcheng Yang, Shengmao Zhang
A novel hydrophilic polymer-based anion exchanger has been described for ion chromatography (IC). It is prepared by grafting polyethyleneimine (PEI) onto the poly(glycidylmethacrylate-divinylbenzene) (GMA-DVB) substrate, followed by hydrolytic treatment to convert the residual epoxide groups onto the surface of GMA-DVB substrates to hydroxyl groups, finally quaternized PEI by a molecule containing epoxide group. Hydrophobic surface of GMA-DVB substrate can be converted to hydrophilic, aiming to reduce unwanted non-ionic interaction from the substrate...
May 15, 2019: Talanta
Antonín Kaňa, Martin Loula, Richard Koplík, Magda Vosmanská, Oto Mestek
The characterisation of inorganic nanoparticles (NPs) by single particle inductively coupled plasma mass spectroscopy is possible only if the spectrometer is capable of measurement with high time-signal resolution. The latest generation of spectrometers allow for measurements with dwell times (dt) shorter than the 100 μs gold standard, i.e. as low as 10 μs. The statistical behaviours of signals obtained with dt values of 10, 20, 50, and 100 μs were tested for 40, 60, and 100 nm silver NPs. Very low measured signals (units of counts) led to the occurrence of zero signal values inside the peaks corresponding to individual NPs...
May 15, 2019: Talanta
Satoshi Tanimoto, Izuka Nishii, Shokyoku Kanaoka
Chitosan/calcium carbonate core-shell type composite microparticles were fabricated via a biomineralization-inspired process with chitosan particles as starting materials. The obtained composite particles were spherical, and the diameter of the composite particles was larger than that of the chitosan particles. XRD measurement indicated that the shell of the composite particle had a crystalline structure. The shell fabrication process was carried out with polyacrylic acid (PAA) or polyglutamic acid (PGlu) as binder molecules between calcium carbonate and chitosan...
February 13, 2019: International Journal of Biological Macromolecules
Vinod S Ipar, Anisha Dsouza, Padma V Devarajan
Curcumin is a promising therapeutic agent that exhibits manifold therapeutic activities. However, it is challenging to study curcumin as it exhibits poor aqueous solubility and low permeability and it is a substrate for P-glycoprotein (P-gp). It is readily metabolized in the body, but many active metabolites of curcumin have been identified that could also be exploited for therapy. Strategies for the oral bioenhancement of curcumin to leverage the potential of curcumin as a therapeutic molecule are discussed here in light of these challenges...
February 15, 2019: European Journal of Drug Metabolism and Pharmacokinetics
Shuisheng Hu, Lin Zhu, Cheong Wing Lam, Longhua Guo, Zhenyu Lin, Bin Qiu, Kwok Yin Wong, Guonan Chen, Zhenhua Liu
A copper(II)-based two-dimensional metal-organic framework with nanosheet structure (CuBDC NS) that possesses peroxidase (POx) mimicking activity was prepared. In the presence of hydrogen peroxide, the system catalyses the oxidation of terephthalic acid to a blue-fluorescent product (excitation = 315 nm; emission = 425 nm). Pyrophosphate has a very strong affinity for Cu2+ ion and blocks the POx-mimicking activity of the CuBDC NS. If, however, inorganic pyrophosphatase is present, the POx mimicking activity is gradually restored because pyrophosphate is hydrolyzed...
February 15, 2019: Mikrochimica Acta
Oscar A Douglas-Gallardo, David Adrian Saez, Stefan Vogt-Geisse, Esteban Vöhringer-Martinez
Carboxylation reactions represent a very special class of chemical reactions that is characterized by the presence of a carbon dioxide (CO2 ) molecule as reactive species within its global chemical equation. These reactions work as fundamental gear to accomplish the CO2 fixation and thus to build up more complex molecules through different technological and biochemical processes. In this context, a correct description of the CO2 electronic structure turns out to be crucial to study the chemical and electronic properties associated with this kind of reactions...
February 16, 2019: Journal of Computational Chemistry
Hafiz Muhammad Jhanzab, Abdul Razzaq, Yamin Bibi, Farhat Yasmeen, Hisateru Yamaguchi, Keisuke Hitachi, Kunihiro Tsuchida, Setsuko Komatsu
Production and utilization of nanoparticles (NPs) are increasing due to their positive and stimulating effects on biological systems. Silver (Ag) NPs improve seed germination, photosynthetic efficiency, plant growth, and antimicrobial activities. In this study, the effects of chemo-blended Ag NPs on wheat were investigated using the gel-free/label-free proteomic technique. Morphological analysis revealed that chemo-blended Ag NPs resulted in the increase of shoot length, shoot fresh weight, root length, and root fresh weight...
February 14, 2019: International Journal of Molecular Sciences
Inmaculada Coleto, Izargi Vega-Mas, Gaetan Glauser, María Begoña González-Moro, Daniel Marino, Idoia Ariz
Nitrogen is an essential element for plant nutrition. Nitrate and ammonium are the two major inorganic nitrogen forms available for plant growth. Plant preference for one or the other form depends on the interplay between plant genetic background and environmental variables. Ammonium-based fertilization has been shown less environmentally harmful compared to nitrate fertilization, because of reducing, among others, nitrate leaching and nitrous oxide emissions. However, ammonium nutrition may become a stressful situation for a wide range of plant species when the ion is present at high concentrations...
February 14, 2019: International Journal of Molecular Sciences
Chahrazad El Abiad, Smaail Radi, Maria A F Faustino, M Graça P M S Neves, Nuno M M Moura
Porphyrins show great promise for future purification demands. This is largely due to their unique features as host binding molecules that can be modified at the synthetic level, and largely improved by their incorporation into inorganic based materials. In this study, we assessed the efficacy of a hybrid material obtained from the immobilization of 5,10,15,20-tetrakis(pentafluorophenyl)-porphyrin on silica surface to remove Pb(II), Cu(II), Cd(II), and Zn(II) ions from water. The new organic-inorganic hybrid adsorbent was fully characterized by adequate techniques and the results show that the hybrid exhibits good chemical and thermal stability...
February 14, 2019: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Kimberly A Finlayson, Frederic D L Leusch, Jason P van de Merwe
Chemical contaminants have been found in the tissues of sea turtles from all over the world; however, very little is known about the effects. Recently, in vitro alternatives to live animal testing have been applied to sea turtles due to their ethical and practical benefits. While primary skin fibroblasts have been established for several species of sea turtle, cells from internal organs are lacking, though they may be more relevant due to the well documented accumulation of contaminants within internal tissues...
February 4, 2019: Science of the Total Environment
Mengru Wang, Maryna Strokal, Peter Burek, Carolien Kroeze, Lin Ma, Annette B G Janssen
Intensive agriculture and rapid urbanization have increased nutrient inputs to Lake Taihu in recent decades. This resulted in eutrophication. We aim to better understand the sources of river export of total dissolved nitrogen (TDN) and phosphorus (TDP) to Lake Taihu in relation to critical nutrient loads. We implemented the MARINA-Lake (Model to Assess River Inputs of Nutrients to seAs) model for Lake Taihu. The MARINA-Lake model quantifies river export of dissolved inorganic and organic N and P to the lake by source from sub-basins...
February 5, 2019: Science of the Total Environment
Tania Ruíz-Vera, Ángeles C Ochoa-Martínez, Sergio Zarazúa, Leticia Carrizales-Yáñez, Iván N Pérez-Maldonado
The aim of this research was to investigate circulating expression levels of three miRNAs (miR-126, miR-155, and miR-145) proposed as predictive CVD biomarkers in Mexican women exposed to inorganic arsenic via drinking water. Mean UAs concentration of 19.5 ± 14.0 μg/g creatinine was found after urine samples were analyzed (n = 105). Significant associations between UAs levels and serum expression levels of miR-155 (p < 0.05) and miR-126 (p < 0.05) were observed after adjustment for assessed co-variables...
February 7, 2019: Environmental Toxicology and Pharmacology
Sushweta Mahalanobish, Sukanya Saha, Sayanta Dutta, Parames C Sil
Arsenic contaminated drinking water consumption is a serious health issue around the world. Chronic inorganic arsenic exposure has been associated with respiratory dysfunctions. It exerts various detrimental effects, disrupting normal cellular homeostasis and turning on severe pulmonary complications. This study elucidated the role of mangiferin, a natural xanthone, against arsenic induced lung toxicity. Chronic exposure of sodium arsenite (NaAsO2 ) at 10 mg/kg bw for 3 months abruptly increased the LDH release in broncho-alveolar lavage fluid, generated reactive oxygen species (ROS), impaired the antioxidant defense and distorted the alveoli architecture...
February 12, 2019: Food and Chemical Toxicology
Marissa Soto, Robert Lewis, J Thomas Curtis
Male, but not female, prairie voles that experience chronic exposure to inorganic mercury display aberrant social behavior - avoiding unfamiliar conspecifics rather than approaching them. The mechanisms that underlie such behavioral changes are unknown, but likely involve the hypothalamus-pituitary-adrenal (HPA) axis. We tested this hypothesis by providing voles of both sexes with mercury chloride in their drinking water for ten weeks and then staging same-sex dyadic encounters after which plasma was assayed for corticosterone as an index of HPA activity...
February 12, 2019: Hormones and Behavior
Patrícia Pereira, Malgorzata Korbas, Vitória Pereira, Tiziana Cappello, Maria Maisano, João Canário, Armando Almeida, Mário Pacheco
Neuronal and sensory toxicity of mercury (Hg) compounds has been largely investigated in humans/mammals with a focus on public health, while research in fish is less prolific and dispersed by different species. Well-established premises for mammals have been governing fish research, but some contradictory findings suggest that knowledge translation between these animal groups needs prudence [e.g. the relative higher neurotoxicity of methylmercury (MeHg) vs. inorganic Hg (iHg)]. Biochemical/physiological differences between the groups (e...
February 12, 2019: Biochimica et biophysica acta. General subjects
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