Sorption of selected pharmaceuticals by a river sediment: role and mechanisms of sediment or Aldrich humic substances

Abstract

Sorption of pharmaceuticals onto sediments is frequently related to organic matter content. Thus, the present work aimed to compare the effect of humic substances (HS) extracted from a river sediment versus Aldrich (HS) on the sorption of selected pharmaceuticals onto this river sediment. The results exhibited no "unique" effect of the presence of HS from the same origin. Thus, the sediment HS increased the sorption of sulfamethoxazole (SMX), diclofenac (DCF), and trimethoprim (TMP), but reduced the sorption of atenolol (ATN). The presence of Aldrich HS increased the sorption of TMP and ATN and decreased the sorption of SMX and DCF. Fluorescence quenching measurements revealed that these effects cannot be explained only by the presence of pharmaceutical HS associations. The use of several sorption models suggested that the sorption of SMX, DCF, and ATN involves multilayer mechanisms. Furthermore, it was pointed out that the presence of HS does not change the sorption mechanisms although it was observed interaction between HS and the sediment. Indeed, the sediment HS sorbs onto the sediment whereas the Aldrich HS tends to mobilize organic compounds from the sediment to the solution.

Modes of selenium occurrence and LCD modeling of selenite desorption/adsorption in soils around the selenium-rich core, Ziyang County, China

Abstract

Studying the modes of selenium occurrence in high-Se soils and its behaviors can improve understanding and evaluating its cycling, flux, and balance in geo-ecosystems and its influence on health. In this paper, using a modified sequential chemical extraction technique, seven operationally defined selenium fractions and Se valence distribution were determined about five soils in which paddy was planted (W1, W2, W3, W4, W5) and five soils in which maize was planted (H1, H2, H3, H4, H5) around the selenium-rich core, Ziyang County, Shaanxi Province, China. The results show that selenium fractions in the soils mainly include sulfide/selenide and base-soluble Se, and ligand-exchangeable Se is also high for five soils in which paddy was planted. For water-soluble Se, Se (IV) is main Se valence and almost no Se (VI) was determined about five soils in which paddy was planted, while almost 1:1 of Se (IV) and Se (VI) coexist about five soils in which maize was planted. For exchangeable Se, similar results were found. For the first time, two typical high-Se soils (W1 soil and H1 soil) were chosen to measure the pH-dependent solid-solution distribution of selenite in the pH range 3–9, and the results were explained using LCD (ligand and charge distribution) adsorption modeling. The desorbed selenite concentrations from the two soils are in general underestimated by the model due to a comparable binding affinity of phosphate and selenite on goethite and much lower amount of total selenite than total reactively adsorbed phosphate. The pH dependency of adsorption of selenite added to the soil can be successfully described with the LCD model for W1 soil. Whereas considering the influence of Al-oxides, by lowering selenite adsorption affinity constant K of Se adsorption on goethite by 16 times, the LCD model can describe the adsorption much better. The results can help to understand selenium cycling, flux, and balance in typical high-Se soils.

Distillers’ grains anaerobic digestion residue biochar used for ammonium sorption and its effect on ammonium leaching from an Ultisol

Abstract

The aim of this work was to explore the potential application of biochar from distillers' grains anaerobic digestion residue pyrolyzed at 700 °C (ADR-DG₇₀₀) to ammonium (NH₄⁺) adsorption from aqueous solution, as well as its effect on NH₄⁺ leaching from an Ultisol. The adsorption kinetic of NH₄⁺ on the ADR-DG₇₀₀ could be described by an Elovich model (R² = 0.995), and the combined Langmuir-Freundlich model (R² = 0.997) fitted the isotherm data better than the Langmuir, Freundlich, Redlich-Peterson, and Temkin models with a maximum adsorption of 11.41 mg N g⁻¹. The NH₄⁺ adsorption on ADR-DG₇₀₀ was mainly controlled by the cation exchange, the surface complexation with oxygen-containing functional groups of carboxyl C〓O (C▬O) and carbohydrate C▬OH, as well as the electrostatic interactions with Si▬O▬Si functional group. In addition, the ADR-DG₇₀₀ soil application reduced 2.48–20.67% of NH₄⁺-N leaching loss after nitrogen fertilizer application in an Ultisol. These results suggested that the ADR-DG₇₀₀ could be a sorbent for NH₄⁺-contaminated water as well as an inhibitor for soil NH₄⁺ leaching.

Heavy metals transfer in the olive tree and assessment of food contamination risk

Abstract

Due to constraints of fresh water for agricultural irrigation, wastewater was used for irrigation of agricultural land as alternative water resources in arid and semi-arid Tunisian regions. However, long-term irrigation may cause contamination by heavy metals in the soil as well as for crops, thus becoming a threat to humans. To understand the effect of irrigation with wastewater on the concentrations of heavy metals Cr, Cu, Mn, Zn, and Pb, in soil and plants, soil samples and plants were collected and analyzed. Results have shown that all soil samples do not exhibit extreme values. The content of heavy metals in the surface layer (0–30 cm) is much higher than that in depth. Overall, the concentrations of Mn, Pb, Cu, Cr, and Zn in soil were found to be lower than the authorized national safety limits. Moreover, the content in both parts of forage crops have not exceeded the WHO standard. For olive trees, no negative values were found in the different organs, which was also true for the extracted oil. An exception happened for the oils produced from fallen olives in direct contact with the wastewater and the soil. Therefore, to ensure food security and wastewater use for irrigation, monitoring and control of pollution is required.

Graphical abstract

Biomass production from treated wastewater without risk

Quantification of polychlorinated biphenyl contamination using human placenta as biomarker from Punjab Province, Pakistan

Abstract

The present study biomonitored the placental polychlorinated biphenyl (PCB) concentrations in women from Punjab Province, Pakistan, that provides the pioneer data for occurrence and body burden of PCBs in placental tissues from South Asian women. The ∑₃₄PCB concentrations in placental tissues were ranged from 20.2 to 115.98 ng/g lipid weight (lip. wt.), with predominance of tetra-PCB (54.67%). The levels of ∑₈DL-PCBs and ∑₆-indicator PCBs were ranged from 2.03 to 27.64 ng/g (lip. wt.) and 1.71 to 30.8 ng/g (lip. wt.), respectively. The WHO-TEQ2005 values for DL-PCBs were ranged from 1.18 × 10⁻⁵ to 0.067 ng/g (lip. wt.), with highest value evaluated for CB-126. The estimated daily intake (EDI) for DL-PCBs was ranged from 9.27 × 10⁻⁸ to 5.25 × 10⁻⁴ pg WHO-TEQ/kg body weight (bw), which was within the tolerable daily intake (TDI) values established by international organizations. The spatial distribution patterns of Σ₃₄PCB concentrations from study area have shown relative higher concentrations in samples from urban and industrial cities than rural areas, and industrial and urban releases along with e-waste handling were recognized as vital PCB sources in the environment. In order to ascertain the transplacental transfer of PCBs, the fetal growth parameters were correlated with the ∑₃₄PCB concentrations in placental tissues. The relationship between ∑₃₄PCB concentrations in placental tissues and infant's anthropometric measures through multiple linear regression showed a negative correlation of infant's body weight (R² = 0.0728), crown to heel length (R² = 0.068), head circumference (R² = 0.0342), chest circumference (R² = 0.0001), and mid arm circumference (R² = 0.0096) that noticeably highlights the inhibited fetal anthropometric development associated with maternal PCB bioaccumulation. Hence, an immediate elimination of ongoing PCB addition in the studied area has been emphasized and further investigations are suggested to appropriately manage the public and neonatal health risks in the region.

The toxicity of cadmium ion (Cd 2+ ) to phycocyanin: an in vitro spectroscopic study

Abstract

The pollution of heavy metals is a severer problem for the ecosystems in waters. The toxicity of Cd²⁺ on phycocyanin (PC) is studied in molecular level in this work. The fluorescence quenching of PC is observed by the adding Cd²⁺ from 0 to 500 × 10⁻⁷ mol L⁻¹. From the theoretical calculation and the time-resolved fluorescence decay profiles, the fluorescence quenching of PC by Cd²⁺ is found to be static. The synchronous fluorescence spectra are used to study the change in amino acid residues of PC molecules, indicating that the effect of Cd²⁺ on the Trp of PC is more significant than the Tyr. The UV-Vis absorbance of tetrapyrrole decreases from 0.26 to 0.23 cps with increasing Cd²⁺ concentration, suggesting that Cd²⁺ affects the light adsorption and the photosynthesis function of PC. The circular dichroism spectra reveal that adding Cd²⁺ also changes the secondary structure (α-helix) of PC.

Dermoscopy for the detection and safe extraction of an intracutaneous foreign body Runing Title: Therapeutic Dermoscopy in detection and safe extraction

Publication date: Available online 10 March 2018
Source:Journal of the American Academy of Dermatology
Author(s): Sidharth Sonthalia, Abhijeet Kumar Jha, Feroze Kaliyadan

Fibrosing Vasculitides: A Heuristic for Investigation

Publication date: Available online 10 March 2018
Source:Journal of the American Academy of Dermatology
Author(s): Audrey Rutherford, Stephen Erickson, Emily Keimig, Heather Wickless

Inflammatory arthritis in pediatric patients with morphea

Publication date: Available online 10 March 2018
Source:Journal of the American Academy of Dermatology
Author(s): Sakeen W. Kashem, Colleen K. Correll, Richard K. Vehe, Patricia M. Hobday, Bryce A. Binstadt, Sheilagh M. Maguiness
BackgroundMorphea, or 'localized scleroderma', is an inflammatory disorder resulting in fibrosis of the skin and subcutaneous tissues. Joint contractures, arthralgias and functional compromise are recognized associations of pediatric morphea. The co-existence of inflammatory arthritis and morphea is not well-described in the literature.ObjectiveTo investigate the relationship between pediatric morphea and inflammatory arthritis with regards to cutaneous, musculoskeletal and laboratory findings and treatment regimens.MethodsA systematic retrospective chart review of 53 patients with pediatric morphea was performed and analyzed for morphea subtypes, arthritic joint involvement, serum autoantibodies and therapeutic interventions.ResultsEleven out of 53 patients had polyarthritis that involved joints unrelated to the site of the cutaneous morphea. They were mostly female and presented with either the linear or generalized subtypes of morphea. Serum levels of antinuclear antibodies were more significantly elevated in patients with arthritis. All children were treated with methotrexate in addition to other systemic and/or topical immunosuppressive agents.LimitationThis was a small, single center, retrospective study.ConclusionPediatric morphea co-existed with inflammatory arthritis in 11/53 children. Further understanding and appreciation of this relationship may direct more intensive therapy and musculoskeletal screening

Teaser

Pediatric morphea is associated with joint contractures and arthralgia. The findings of this study support the association of inflammatory arthritis with pediatric morphea. Understanding of the relationship between morphea and arthritis in children should lead to increased musculoskeletal vigilance and appropriate systemic therapy.

Dupilumab for Hand Eczema

Publication date: Available online 10 March 2018
Source:Journal of the American Academy of Dermatology
Author(s): Matthew J. Zirwas

IDH2 mutations are commonly associated with 1p/19q codeletion in diffuse adult gliomas

Diffuse gliomas are classified according to the 2016 World Health Organization (WHO) Classification of Tumors of the Central Nervous System,¹ which combines histological and molecular features. Diagnosis requires the assessment of mutations in the isocitrate dehydrogenase genes (IDH1 and IDH2), key genetic alterations characterizing gliomas with favorable outcome.²

The clinical trials landscape for glioblastoma: is it adequate to develop new treatments?

Abstract

Background

There have been few treatment advances for patients with glioblastoma (GBM) despite increasing scientific understanding of the disease. While factors such as intrinsic tumor biology and drug delivery are challenges to developing efficacious therapies, it is unclear whether the current clinical trial landscape is optimally evaluating new therapies and biomarkers.

Methods

We queried ClinicalTrials.gov for interventional clinical trials for patients with GBM initiated between January 2005 to December 2016 and abstracted data regarding phase, status, start and end dates, testing locations, endpoints, experimental interventions, sample size, clinical presentation/indication, and design to better understand the clinical trials landscape.

Results

Only approximately 8%-11% of patients with newly diagnosed GBM enroll on clinical trials with a similar estimate for all patients with GBM. Trial duration was similar across phases with median time to completion between 3 and 4 years. While 93% of clinical trials were in phases I-II, 26% of the overall clinical trial patient population was enrolled on phase III studies. Of the 8 completed phase III trials, only one reported positive results. Although 58% of the phase III trials were supported by phase II data with a similar endpoint, only 25% of these phase II trials were randomized.

Conclusions

The clinical trials landscape for GBM is characterized by long development times, inadequate dissemination of information, suboptimal go/no-go decision-making, and low patient participation.

Dermoscopy for the detection and safe extraction of an intracutaneous foreign body Runing Title: Therapeutic Dermoscopy in detection and safe extraction

Inflammatory arthritis in pediatric patients with morphea

Pediatric morphea is associated with joint contractures and arthralgia. The findings of this study support the association of inflammatory arthritis with pediatric morphea. Understanding of the relationship between morphea and arthritis in children should lead to increased musculoskeletal vigilance and appropriate systemic therapy.

Dupilumab for Hand Eczema

Fibrosing Vasculitides: A Heuristic for Investigation

High-performance for hydrogen evolution and pollutant degradation of reduced graphene oxide/two-phase g-C 3 N 4 heterojunction photocatalysts

Abstract

We have successfully synthesized the composites of two-phase g-C₃N₄ heterojunction photocatalysts by one-step method. And the reduced graphene oxide/two-phase g-C₃N₄ heterojunction photocatalyst was fabricated via a facile hydrothermal reduction method. The characterization results indicated that the two-phase g-C₃N₄ was integrated closely, and the common phenomenon of agglomeration for g-C₃N₄ was significantly reduced. Moreover, the oxidized graphene was reduced successfully in the composites and the graphene was overlaid on the surface or the interlayers of g-C₃N₄ heterojunction composite uniformly. In addition, we have carried out the photocatalytic activity experiments by H₂ evolution and rhodamine B removal, tetracycline removal under the visible light irradiation. The results revealed that the composite has improved the separation efficiency a lot than the pure photocatalyst. The photocurrent test demonstrated that the recombination of electrons and holes were efficiently inhibited as well as enhanced the photocatalytic activity. The 0.4% rGO loaded samples, 0.4% rGOCN2, own the best performance. Its rate of H₂ evolution was 15 times as high as that of the pure g-C₃N₄.

The regulatory role of endogenous iron on greenhouse gas emissions under intensive nitrogen fertilization in subtropical soils of China

Abstract

Anaerobic batch experiments were conducted to study the regulatory role of endogenous iron in greenhouse gas emissions under intensive nitrogen fertilization in subtropical soils of China. Fe²⁺, Fe³⁺, and NO₃⁻-N dynamics and N₂O, CH₄, and CO₂ emissions, as well as the relationships between N fertilizer, endogenous iron, and greenhouse gas emissions were investigated. The emissions of N₂O increased to different extents from all the test soils by N1 (260 mg N kg⁻¹) application compared with N0. After 24 days of anaerobic incubation, the cumulative emissions of N₂O from red soils in De'an (DR) were significantly higher than that from paddy soils in De'an (DP) and Qujialing (QP) under N1. However, N application enhanced CH₄ and CO₂ emissions from the red soils slightly but inhibited the emissions from paddy soils. The maximal CH₄ and CO₂ emission fluxes occurred in DP soil without N input. Pearson's correlation analysis showed that there were significant correlations (P < 0.01) between Fe²⁺ and Fe³⁺, NO₃⁻-N, (N₂O + N₂)-N concentrations in DP soil, implying that Fe²⁺ oxidation was coupled with nitrate reduction accompanied by (N₂O + N₂)-N emissions and the endogenous iron played a regulatory role in greenhouse gas emissions mainly through the involvement in denitrification. The proportion of the electrons donated by Fe²⁺ used for N₂O production in denitrification in DP soil was approximately 37.53%. Moreover, positive correlations between Fe²⁺ and CH₄, CO₂ were found in both DR and QP soils, suggesting that endogenous iron might regulate the anaerobic decomposition of organic carbon to CH₄ and CO₂ in the two soils. Soil pH was also an important factor controlling greenhouse gas emissions by affecting endogenous iron availability and C and N transformation processes.

Growth and nutrition of Agelastica coerulea (Coleoptera: Chrysomelidae) larvae changed when fed with leaves obtained from an O 3 -enriched atmosphere

Abstract

A series of laboratory no-choice assays were performed to test changes in the feeding, growth, and nutrition of leaf beetle (Agelastica coerulea) larval instars on O₃-treated leaves of Japanese white birch (Betula platyphylla var. japonica). Larvae fed with O₃-treated leaves grew and developed significantly faster throughout their developmental cycle than the corresponding controls. The growth rate (GR) and consumption index (CI) were mostly decreased with age for both control and O₃-treated leaves. Efficiency of conversion of both ingested and digested food (ECI, ECD) showed an increase from the 2nd to the 4th instar, after which they decreased significantly and reached the lowest value in the last larval instars (7th). GR, CI, ECI, and ECD were greater and approximate digestibility (AD) was lower in larvae fed with O₃-treated leaves than those fed with control leaves. This indicated that the greater rate of growth on fumigated leaves was due primarily to a greater rate of consumption (i.e., O₃ increased the "acceptability" of the host more than "suitability") and efficiency in converting food into body mass. Overall, larval performance seemed to have improved when fed with O₃-treated leaves in these assays. This study suggests that insects may be more injurious to O₃-treated plants and warrants further investigations on birch-beetle interactions under field conditions.

Study on turbulence characteristics and sensitivity of quadrant analysis to threshold level in Lake Taihu

Abstract

The identification of coherent structures is very important in investigating the sediment transport mechanism and controlling the eutrophication in shallow lakes. This study analyzed the turbulence characteristics and the sensitivity of quadrant analysis to threshold level. Simultaneous in situ measurements of velocities and suspended sediment concentration (SSC) were conducted in Lake Taihu with acoustic Doppler velocimeter (ADV) and optical backscatter sensor (OBS) instruments. The results show that the increase in hole size makes the difference between dominant and non-dominant events more distinct. Wind velocity determines the frequency of occurrence of sweep and ejection events, which provide dominant contributions to the Reynolds stress. The increase of wind velocity enlarges the magnitude of coherent events but has little impact on the events frequency with the same hole size. The events occurring within short periods provide large contributions to the momentum flux. Transportation and diffusion of sediment are in control of the intermittent coherent events to a large extent.