A novel electrocatalytic approach for effective degradation of Rh-B in water using carbon nanotubes and agarose

Abstract

Carbon nanotubes (CNTs)/agarose (AG) membrane on the ITO (indium tin oxide) conductive glass, with high efficiency of electrocatalytic degradation for rhodamine B (Rh-B) in water, was prepared using an easy and green method. The prepared CNTs/AG membrane was characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD), energy dispersive spectra (EDS), infrared spectroscopy (IR), and electrochemical impedance spectroscopy (EIS). The results revealed that CNTs were dispersed in the AG membrane. Additionally, the electrocatalytic activities for Rh-B were conducted on the electrochemical workstation with a three-electrode system. Both initial pH and potential played an important role in the process of electrocatalytic degradation. At pH 3 and potential reaching 4 V, the removal rate of Rh-B (10 mg/L) in water achieved 96% within 20 min. The stability of the prepared CNTs/AG membrane was also investigated. Besides, the toxicities of the main intermediates from the electrocatalytic degradation for Rh-B were calculated using the ECOSAR program and EPIWIN software, and results indicated that the toxicities of some intermediates were higher than those of the parent pollutant (Rh-B). These findings provided a light-spot to simplify the preparation of efficient working electrode and emphasized the possible potential risks from intermediates at the same time.

Swift fabrication of Ag nanostructures using a colloidal solution of Holostemma ada-kodien (Apocynaceae) – Antibiofilm potential, insecticidal activity against mosquitoes and non-target impact on water bugs

Publication date: Available online 17 February 2018
Source:Journal of Photochemistry and Photobiology B: Biology
Author(s): Sami A. Alyahya, Marimuthu Govindarajan, Naiyf S. Alharbi, Shine Kadaikunnan, Jamal M. Khaled, Ramzi A. Mothana, Mohammed N. Al-anbr, Baskaralingam Vaseeharan, Ramachandran Ishwarya, Mariappan Yazhiniprabha, Giovanni Benelli
Recent research in parasitology focused on the efficacy of green fabricated nanomaterials as novel insecticides. In this study, we synthesized poly-dispersed, stable, and cluster-shaped silver nanoparticles (AgNPs) using the leaf extract of Holostemma ada-kodien. The cluster-shaped AgNPs were characterized by ultraviolet-visible spectroscopy, Fourier transform infrared spectroscopy, scanning electron microscopy, high-resolution transmission electron microscopy, energy dispersive X-ray, and X-ray diffraction analysis. The efficacy of H. ada-kodien leaf extract and AgNPs in vector control was evaluated against the mosquitoes Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus, which act as major vectors of important parasitic and arboviral diseases. AgNPs showed higher toxicity if compared to the H. ada-kodien leaf aqueous extract, LC50 towards larvae of A. stephensi, A. aegypti, and C. quinquefasciatus were 12.18, 13.30, and 14.70 μg/ml, respectively. AgNPs tested on non-target water bugs, Diplonychus indicus, LC50 value was 623.48 μg/ml. Furthermore, 100 μl/ml of AgNPs achieved significant antimicrobial activity against Bacillus pumilus, Enterococcus faecalis, Pseudomonas aeruginosa, Proteus vulgaris, and Candida albicans. Light and confocal laser scanning microscopy highlighted a major impact of the H. ada-kodien-synthesized AgNPs on the external topography and architecture of microbial biofilms for both Gram-positive and Gram-negative bacteria. Overall, this study sheds light on the insecticidal and antibiofilm potential of H. ada-kodien-synthesized AgNPs, a potential green resource for the rapid synthesis of polydispersed, cluster-shaped, and highly stable AgNPs.

Graphical abstract

Editorial Board

The combination of Luffa cylindrical fibers and metal oxides offers a highly performing hybrid fiber material in water decontamination

Abstract

The present investigation aims to prepare a hybrid material from Luffa cylindrica and metal oxides (ZnO, Al₂O₃) by precipitation for different percentages of zinc and aluminum (1, 2, and 4%) with a determined amount of biomass (a diameter of 250 μm). Physicochemical characterization of "Luffa cylindrica" and "Luffa cylindrica-metal oxides" was carried out by Boehm titration, pH_PZC determination, scanning electron microscopy (SEM), and FTIR spectroscopic analysis. The process was optimized according to the adsorbed amount of methylene blue: MB (cationic dye) and methyl orange: MO (anionic dye) onto Luffa cylindrica and hybrid materials prepared. The results demonstrated the efficiency of the designed hybrid materials in removing MB and MO, accelerating the biosorption process and improving the performance of Luffa cylindrica fibers. The highest quantities adsorbed of dyes were obtained by the hybrid material prepared using 4% ZnO. Finally, the Brouers-Sotolongo mathematical modeling of kinetics was used in order to describe the pollutants retention process.

Lethal and sub-lethal effects of cyproconazole on freshwater organisms: a case study with Chironomus riparius and Dugesia tigrina

Abstract

The fungicide cyproconazole (CPZ) inhibits the biosynthesis of ergosterol, an essential sterol component in fungal cell membrane and can also affect non-target organisms by its inhibitory effects on P450 monooxygenases. The predicted environmental concentration of CPZ is up to 49.05 μg/L and 145.89 μg/kg in surface waters and sediments, respectively, and information about CPZ toxicity towards non-target aquatic organisms is still limited. This study aimed to address the lack of ecotoxicological data for CPZ, and thus, an evaluation of the lethal and sub-lethal effects of CPZ was performed using two freshwater invertebrates (the midge Chironomus riparius and the planarian Dugesia tigrina). The estimated CPZ 48 h LC₅₀ (95% CI) was 17.46 mg/L for C. riparius and 47.38 mg/L for D. tigrina. The emergence time (EmT₅₀) of C. riparius was delayed by CPZ exposure from 0.76 mg/L. On the other hand, planarians showed higher tolerance to CPZ exposure. Sub-lethal effects of CPZ on planarians included reductions in locomotion (1.8 mg/L), delayed photoreceptors regeneration (from 0.45 mg/L), and feeding inhibition (5.6 mg/L). Our results confirm the moderate toxicity of CPZ towards aquatic invertebrates but sub-lethal effects observed also suggest potential chronic effects of CPZ with consequences for population dynamics.

Uptake and elimination kinetics of trifluralin and pendimethalin in Pheretima spp. and Eisenia spp.

Abstract

The purpose of this study was to clarify the kinetic bioaccumulation potential of herbicides in the earthworm, Pheretima spp., the most common earthworms throughout Asia, and Eisenia spp., litter-feeding earthworms included in the test species recommended by the Organization for Economic Co-operation and Development. The kinetic bioaccumulation factors of trifluralin and pendimethalin were estimated from an uptake test for 10 or 12 days and from an elimination test for 10 days. The time required to reach a steady state following herbicide exposure was 7 days for both herbicides in Eisenia spp. and 1 day in Pheretima spp. The uptake rate constant (g-soil/g-worm/day) and elimination rate constant (per day) for trifluralin were 2.1 and 0.23 in Eisenia spp. and 0.42 and 0.45 in Pheretima spp., respectively, and those for pendimethalin were 1.5 and 0.26 in Eisenia spp. and 0.27 and 1.0 in Pheretima spp., respectively. Kinetic bioaccumulation factors of both herbicides were relatively close to bioaccumulation factors in steady state and were higher in Eisenia spp. (8.9 for trifluralin and 5.7 for pendimethalin) than in Pheretima spp. (0.95 and 0.26). These results demonstrated that the herbicide bioaccumulation risk is lower for Pheretima spp. than for Eisenia spp. because of the lower uptake rate and higher elimination rate in Pheretima spp.

Soft Ethics and the Governance of the Digital

Serlopitant for the treatment of chronic pruritus: results of a randomized, multicenter, placebo-controlled phase 2 clinical trial

The substance P/neurokinin 1 receptor (NK1R) pathway is critical in chronic pruritus; anecdotal evidence suggests antagonism of this pathway can reduce chronic itch.

Diana and Ernie return: on Carolina Sartorio’s Causation and Free Will

Abstract

In the final chapter of her Causation and Free Will, Carolina Sartorio offers (among other things) a novel reply to an original-design argument for the thesis that determinism is incompatible with free will and moral responsibility, an argument that resembles Alfred Mele's zygote argument in Free Will and Luck. This article assesses the merits of her reply. It is concluded that Sartorio has more work to do if she is to lay this style of argument to rest.

Electrokinetic-Fenton remediation of organochlorine pesticides from historically polluted soil

Abstract

Soil contamination by persistent organic pollutants (POPs) poses a great threat to historically polluted soil worldwide. In this study, soils were characterized, and organochlorine pesticides contained in the soils were identified and quantified. Individual electrokinetic (IE), EK-Fenton-coupled technologies (EF), and enhanced EK-Fenton treatment (E-1, E-2, and E-3) were applied to remediate soils contaminated with hexachloro-cyclohexane soprocide (HCH) and dichloro-diphenyl-trichloroethane (DDT). Variation of pH, electrical conductivity, and electroosmotic flow was evaluated during the EK-Fenton process. The IE treatment showed low removal efficiency for HCHs (30.5%) and DDTs (25.9%). In the EF treatment, the highest removal level (60.9%) was obtained for α-HCH, whereas P,P-DDT was the lowest (40.0%). Low solubility of pollutants impeded the HCH and DDT removal. After enhanced EK-Fenton treatment, final removal of pollutants decreased as follows: β-HCH (82.6%) > γ-HCH (81.6%) > α-HCH (81.2%) > δ-HCH (80.0%) > P,P-DDD (73.8%) > P,P-DDE (73.1%) > P,P-DDT (72.6%) > O,P-DDT (71.5%). The results demonstrate that EK-Fenton is a promising technology for POP removal in historically polluted soil.

Lead facilitates foci formation in a Balb/c-3T3 two-step cell transformation model: role of Ape1 function

Abstract

Several possible mechanisms have been examined to gain an understanding on the carcinogenic properties of lead, which include among others, mitogenesis, alteration of gene expression, oxidative damage, and inhibition of DNA repair. The aim of the present study was to explore if low concentrations of lead, relevant for human exposure, interfere with Ape1 function, a base excision repair enzyme, and its role in cell transformation in Balb/c-3T3. Lead acetate 5 and 30 μM induced APE1 mRNA and upregulation of protein expression. This increase in mRNA expression is consistent throughout the chronic exposure. Additionally, we also found an impaired function of Ape1 through molecular beacon-based assay. To evaluate the impact of lead on foci formation, a Balb/c-3T3 two-step transformation model was used. Balb/c-3T3 cells were pretreated 1 week with low concentrations of lead before induction of transformation with n-methyl-n-nitrosoguanidine (MNNG) (0.5 μg/mL) and 12-O-tetradecanoylphorbol-13-acetate (TPA) (0.1 μg/mL) (a classical two-step protocol). Morphological cell transformation increased in response to lead pretreatment that was paralleled with an increase in Ape1 mRNA and protein overexpression and an impairment of Ape1 activity and correlating with foci number. In addition, we found that lead pretreatment and MNNG (transformation initiator) increased DNA damage, determined by comet assay. Our data suggest that low lead concentrations (5, 30 μM) could play a facilitating role in cellular transformation, probably through the impaired function of housekeeping genes such as Ape1, leading to DNA damage accumulation and chromosomal instability, one of the most important hallmarks of cancer induced by chronic exposures.

Analysing the accuracy of machine learning techniques to develop an integrated influent time series model: case study of a sewage treatment plant, Malaysia

Abstract

The function of a sewage treatment plant is to treat the sewage to acceptable standards before being discharged into the receiving waters. To design and operate such plants, it is necessary to measure and predict the influent flow rate. In this research, the influent flow rate of a sewage treatment plant (STP) was modelled and predicted by autoregressive integrated moving average (ARIMA), nonlinear autoregressive network (NAR) and support vector machine (SVM) regression time series algorithms. To evaluate the models' accuracy, the root mean square error (RMSE) and coefficient of determination (R²) were calculated as initial assessment measures, while relative error (RE), peak flow criterion (PFC) and low flow criterion (LFC) were calculated as final evaluation measures to demonstrate the detailed accuracy of the selected models. An integrated model was developed based on the individual models' prediction ability for low, average and peak flow. An initial assessment of the results showed that the ARIMA model was the least accurate and the NAR model was the most accurate. The RE results also prove that the SVM model's frequency of errors above 10% or below − 10% was greater than the NAR model's. The influent was also forecasted up to 44 weeks ahead by both models. The graphical results indicate that the NAR model made better predictions than the SVM model. The final evaluation of NAR and SVM demonstrated that SVM made better predictions at peak flow and NAR fit well for low and average inflow ranges. The integrated model developed includes the NAR model for low and average influent and the SVM model for peak inflow.

Nerve reinnervation and itch behaviour in a rat burn wound model

ABSTRACT

In this study, we investigated whether post-burn itch in rats, after a full thickness burn, is correlated to the nervous reinnervation of the burn wound area. For this purpose, we determined scratching duration (expressed as sec/hr) at 24 hours, 2, 4, 8 and 12 weeks post-burn and combined this with immunohistochemistry for protein gene product 9.5 (PGP9.5) to identify all nerve fibers, calcitonin gene related peptide (CGRP) to identify peptidergic fibers, tyrosine hydroxylase (TH) for sympathetic fibers and growth-associated protein 43 (GAP-43) for regrowing fibers.

We found a modest, but highly significant, increase in scratching duration of all burn wound rats from 3 to 12 weeks post-burn (maximally 63±9.5 sec/hr compared to sham 3.1±1.4 sec/hr at 9 weeks). At 24 hours post-burn, all nerve fibers had disappeared from the burn area. Around 4 weeks post-burn PGP 9.5- and CGRP-immunoreactive nerve fibers returned to control levels. TH- and GAP-43-IR nerve fibers, which we found to be almost completely co-localized, did not regrow. No correlation was found between scratching duration and nervous reinnervation of the skin.

The present results suggest that in rat, like in human, burn wound healing will induce increased scratching, which is not correlated to nervous reinnervation. This article is protected by copyright. All rights reserved.

Dicer inactivation stimulates limb regeneration ability in Xenopus laevis

Abstract

The ontogenetic decline of regeneration capacity in the anuran amphibian Xenopus makes it an excellent model for regeneration studies. However, the cause of the regeneration ability decline is not fully understood. MicroRNAs regulate animal development, and have been indicated in various regeneration situations. However, little is known about the role of microRNAs during limb regeneration in Xenopus. This study investigates the effect of Dicer, an enzyme responsible for microRNA maturation, on limb development and regeneration in Xenopus. Dicer is expressed in the developing Xenopus limbs, and is upregulated after limb amputation during both regeneration-competent and -deficient stages of tadpole development. Inactivation of Dicer in early (NF stage 53) tadpole limb buds leads to shorter tibulare/fibulare formation, but does not affect limb regeneration. However, in late stage, regeneration-deficient tadpole limbs (NF stage 57), Dicer inactivation restores the regeneration blastema, and stimulates limb regeneration. Thus, our results demonstrated that Xenopus limb regeneration can be stimulated by inactivation of Dicer in non-regenerating tadpoles, indicating that microRNAs present in late stage tadpole limbs may be involved in the ontogenetic decline of limb regeneration in Xenopus. This article is protected by copyright. All rights reserved.

Role of Bi-Weekly Serum Galactomannan Screening for the Diagnosis of Invasive Aspergillosis in Hematologic Cancer Patients

Summary

Invasive aspergillosis (IA) is a life-threatening infection affecting hematologic cancer patients with chemotherapy-induced neutropenia. The diagnosis of IA often relies on the detection of galactomannan (GM) in serum or bronchoalveolar lavage fluid (BAL). Bi-weekly serum GM screening has been proposed for a preemptive therapeutic approach of IA in patients not receiving mold-active prophylaxis. We have analyzed all IA cases among patients with hematologic malignancies and prolonged chemotherapy-induced neutropenia (>14 days) in our institution over a 10-year period (2007-2017). Serum GM was measured twice weekly and mold-active prophylaxis was not routinely administered. Thirty IA cases were observed and a positive serum GM was the first indicator of IA in 10 (33%) of them, which represents a need of approximately 500 GM tests for the detection of a single IA case. In the other 20 (67%) cases, suggestive chest CT lesion was the first sign of IA and bronchoscopy was required in 15 (50%) cases with negative serum GM for establishing the diagnosis of probable/proven IA. A positive serum GM was associated with a worse prognosis (57% 12-week survival versus 100% among serum GM-negative patients, p=0.006), irrespective of the timing of GM positivity compared to CT. We concluded that bi-weekly serum GM screening demonstrated limited benefit in this population.

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Fungal infections in patients with inflammatory bowel disease: a systematic review

Summary

Background

Despite reports of fungal infections in patients with inflammatory bowel disease (IBD), their clinical and microbiological characteristics remain unknown.

Objectives

The aim of this systematic review is to examine all available evidence regarding fungal infections in patients with IBD.

Methods

Systematic search of PubMed (through 27 May 2017) for studies providing data on clinical, microbiological, treatment and outcome data of fungal infections in patients with IBD. The primary study outcome was to record the most common fungal species in patients with IBD. Secondary outcomes were classified into three categories: a) characteristics of fungal infections; b) data on IBD; and c) treatment and outcomes of fungal infections in patients with IBD.

Results

Fourteen studies with data on 1524 patients were included in final analysis. The most common fungal infections in patients with IBD were caused by Candida species (903 infections); the most commonly reported site of Candida infection was the gastrointestinal tract. Available evidence shows that most fungal infections occur within 12 months of IBD treatment and within 6 months when anti-TNFa agents are used.

Conclusions

This systematic review thoroughly describes fungal infections in patients with IBD and provides important information for the early detection and management of these infections.

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Comorbidities of pyoderma gangrenosum: a retrospective multicentric analysis of 126 patients

Abstract

Pyoderma Grangrenosum (PG) is a rare neutrophilic dermatosis with challenging diagnosis and unclear underlying mechanisms. Multifactorial causes are purposed, including neutrophilic dysfunction, aberrant cellular immunity and cytokinic activities, and genetic predispositions¹. An association with a systemic disease is classically described in 25 to 75% of cases, including inflammatory bowel diseases (IBD), inflammatory rheumatological diseases (IRD) and hematological disorders. Association of PG with cardiovascular disorders have also been proposed ^2,3. Due to its rarity, the literature on PG-associated comorbidities remains limited to date.

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Defective RNA sensing by RIG-I in severe influenza virus infection

Summary

Influenza virus infection causes worldwide seasonal epidemics. Although influenza usually is a mild disease, a minority of patients experience very severe fulminating disease courses. Previous studies have demonstrated a role for type I interferon (IFN) in antiviral responses during influenza. However, IFN regulatory factor (IRF)7 deficiency is so far the only genetic cause of severe influenza described in humans. In this study we present a patient with severe influenza A virus (IAV) H1N1 infection during the 2009 Swine Flu pandemic. By whole exome sequencing we identified two variants, p.R71H and p.P885S, located in the CARD and RNA binding domains, respectively, of DDX58 encoding the RNA sensor RIG-I. These variants significantly impair the signaling activity of RIG-I. Similarly, patient cells demonstrate decreased antiviral responses to RIG-I ligands as well as increased pro-inflammatory responses to IAV, suggesting dysregulation of the innate immune response with increased immunopathology. We suggest that these RIG-I variants may have contributed to severe influenza in this patient and advocate that RIG-I variants should be sought for in future studies of genetic factors influencing single-stranded RNA virus infections. This article is protected by copyright. All rights reserved.

The role of the immune system in kidney disease

Abstract

The immune system and the kidneys are closely linked. In health the kidneys contribute to immune homeostasis, while components of the immune system mediate many acute forms of renal disease and play a central role in progression of chronic kidney disease. A dysregulated immune system can have either direct or indirect renal effects. Direct immune-mediated kidney diseases are usually a consequence of autoantibodies directed against a constituent renal antigen, such as collagen IV in anti-glomerular basement membrane disease. Indirect immune-mediated renal disease often follows systemic autoimmunity with immune complex formation, but can also be due to uncontrolled activation of the complement pathways. Though the range of mechanisms of immune dysregulation leading to renal disease is broad, the pathways leading to injury are similar. Loss of immune homeostasis in renal disease results in perpetual immune cell recruitment and worsening damage to the kidney. Uncoordinated attempts at tissue repair, after immune-mediated disease or non-immune mediated injury, result in fibrosis of structures important for renal function, eventually leading to kidney failure. As renal disease often only manifests clinically when substantial damage has already occurred, new diagnostic methods and indeed treatments must be identified to inhibit further progression and promote appropriate tissue repair. Studying cases in which immune homeostasis is re-established may reveal new treatment possibilities. This article is protected by copyright. All rights reserved.

Diminished CXCR5 expression in peripheral blood of patients with Sjögren's syndrome may relate to both genotype and salivary gland homing

ABSTRACT

Genetic investigations of Sjögren's syndrome (SS) have identified a susceptibility locus at p23.3 of chromosome 11, which contains the CXCR5 gene. CXCR5 is a chemokine receptor expressed on B and T cell subsets, and binds the chemotactic ligand CXCL13. We here aimed to link the genetic association with functional effects and explore the CXCR5/CXCL13 axis in SS. Expression quantitative trait loci analysis of the 11q23.3 locus was performed using B cell mRNA expression data from genotyped individuals. Lymphocyte surface markers were assessed by flow cytometry, and CXCL13 levels by a proximity extension assay. CXCR5⁺ and CXCL13⁺ cells in minor salivary glands were detected using immunohistochemistry. Our results demonstrated that SS-associated genetic polymorphisms affected the expression of CXCR5 (p<0.01). Notably, a decreased percentage of CXCR5⁺ cells, with lower CXCR5 expression, was observed for most circulating B and T cell subsets in SS patients, reaching statistical significance in CD19⁺CD27⁺IgD⁺ marginal zone (p<0.001), CD19⁺CD27⁺IgD^- memory (p<0.05) and CD27-IgD double-negative (p<0.01) B cells, and CD4⁺CXCR3^-CCR6⁺ Th17 cells (p<0.05). CXCL13 levels were increased in patient plasma (p<0.001), and immunohistochemical staining revealed expression of CXCL13, and higher numbers of CXCR5⁺ cells (p<0.0001) within focal infiltrates and interstitially in salivary glands of SS patients. In conclusion, we link a genetic susceptibility allele for SS to a functional phenotype in terms of decreased CXCR5 expression. The decrease of CXCR5⁺ cells in circulation was also related to homing of B and T cells to the autoimmune target organ. Therapeutic drugs targeting the CXCR5/CXCL13 axis may be useful in SS. This article is protected by copyright. All rights reserved.

Application of washed MSWI fly ash in cement composites: long-term environmental impacts

Abstract

In the present study, long-term environmental impacts of compact and ground cement composites, in which 30 wt.% of cement was replaced by washed municipal solid wastes incineration (MSWI) fly ash, were investigated for use in building industry. Consecutive leaching tests over a time span of 180 days were performed in acid water, deionized water, and saline water, respectively, with the accumulative concentration of different elements determined in the leachate. Different leaching behaviors are observed among different potential toxic elements (PTEs). For instance, higher concentrations of V in the leachate were observed from the compact cement composites than those from the ground ones. The concentration of Ba in the leachate increased with the decrease of particle size of the cement composites, and an initial increase in the leaching efficiency of Sn was followed by a clear decline with the leaching time. In addition, kinetic study revealed that the leaching behaviors of potential toxic elements follow a second-order model. The results demonstrated that the addition of washed MSWI fly ash into cement can contribute to the attrition resistance, indicating that the washed MSWI fly ash could be a promising alternative for cement as supplementary building materials.

A phase II trial of riluzole, an antagonist of metabotropic glutamate receptor 1 (GRM1) signaling, in patients with advanced melanoma

Summary

Studies demonstrate that GRM, expressed by >60% of human melanomas, may be a therapeutic target. We performed a phase II trial of 100 mg po bid of riluzole, an inhibitor of GRM1 signaling, in patients with advanced melanoma with the primary endpoint of response rate. Thirteen patients with GRM1-positive tumors were enrolled. No objective responses were observed and accrual was stopped. Stable disease was noted in 6 (46%) patients, with 1 patient on study for 42 weeks. Riluzole was well-tolerated, with fatigue (62%) as the most common adverse event. MAPK and PI3K/AKT downregulation was noted in 33% of paired tumor biopsies. Hypothesis generating correlative studies suggested that downregulation of angiogenic markers and increased leuckocytes at the active edge of tumor correlate with clinical benefit. Pharmacokinetic analysis showed inter-patient variability consistent with prior riluzole studies. Future investigations should interrogate mechanisms of biologic activity and advance development of agents with improved bioavailability.

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