The "Oil-Spill Snorkel": an innovative bioelectrochemical approach to accelerate hydrocarbons biodegradation in marine sediments

This study presents the proof-of-concept of the "Oil-Spill Snorkel": a novel bioelectrochemical approach to stimulate the oxidative biodegradation of petroleum hydrocarbons in sediments. The "Oil-Spill Snorkel" consists of a single conductive material (the snorkel) positioned suitably to create an electrochemical connection between the anoxic zone (the contaminated sediment) and the oxic zone (the overlying O-2-containing water). The segment of the electrode buried within the sediment plays a role of anode, accepting electrons deriving from the oxidation of contaminants. Electrons flow through the snorkel up to the part exposed to the aerobic environment (the cathode), where they reduce oxygen to form water. Here we report the results of lab-scale microcosms setup with marine sediments and spiked with crude oil. Microcosms containing one or three graphite snorkels and controls (snorkel-free and autoclaved) were monitored for over 400 days. Collectively, the results of this study confirmed that the snorkels accelerate oxidative reactions taking place within the sediment, as documented by a significant 1.7-fold increase (p = 0.023, two-tailed t-test) in the cumulative oxygen uptake and 1.4-fold increase (p = 0.040) in the cumulative CO2 evolution in the microcosms containing three snorkels compared to snorkel-free controls. Accordingly, the initial rate of total petroleum hydrocarbons (TPH) degradation was also substantially enhanced. Indeed, while after 200 days of incubation a negligible degradation of TPH was noticed in snorkel-free controls, a significant reduction of 12 1% (p = 0.004) and 21 1% (p = 0.001) was observed in microcosms containing one and three snorkels, respectively. Although, the "Oil-Spill Snorkel" potentially represents a groundbreaking alternative to more expensive remediation options, further research efforts are needed to clarify factors and conditions affecting the snorkel-driven biodegradation processes and to identify suitable configurations for field applications

2D Neuronal Network Characterization and Omics Analysis of Engineered human patient-derived Medium Spiny Neurons with RARb mutation

MCOPS12 is an ultra-rare and lethal neurodevelopmental disorder that affects the striatum, the eyes and other internal organs. The disease is linked to mutations in the Retinoic Acid Receptor beta (RARb). Microphthalmia, cognitive and progressive motor impairments are the most common symptoms of MCOPS12. The cognitive and developing motor deterioration is linked to striatal circuitry misregulation. 95% of the striatum is composed of two subpopulations of Medium Spiny Neurons (MSNs). The direct Dopamine Receptor 1 positive (DR1+) and indirect Dopamine Receptor 2 positive (DR2+) striatal MSN subpopulations are antagonistic in their action in the control of motor function. It is hypothesized that a misregulation of the precise balance between DR1+ and DR2+ MSN subpopulations in the striatum can lead to cognitive and movement disorders in MCOPS12 patients. The main aims of this study are: a) To reprogram human MCOPS12 patient- derived somatic cells into iPSCs and generate robust lines, b) To develop a protocol for direct DR1+ and indirect DR2+ MSN differentiation from human iPSCs; valuable tools for the investigation of MCOPS12 biology. In this study I investigated the effect of MCOPS12 RARbR387C mutation on MSNs. For this, I first reprogramed MCOPS12 patient derived blood cells into iPSC lines. Then, I successfully developed a differentiation protocol that generates direct DR1+ and indirect DR2+ MSNs within D55. I differentiated MCOPS12 Patient Derived (PD) iPSCs and wild type (wt) control iPSCs into a mixed DR1+ and DR2+ MSN subpopulation. I performed transcriptomic analysis of these derived MSNs at D55 of differentiation. I also employed CRISPR/Cas9 to induce the RARbR387C mutation into wt control iPSCs and to repair MCOPS12 RARbR387C PD iPSCs to the wt genotype. These engineered iPSCs are a perfect isogenic control to study the RARbR387C mutation and will benefit further MCOPS12 research. Data from the transcriptomic study will be integrated with existing MCOPS12 mice transcriptomic data and clinical patient data. The data integration will hopefully shed new light on MCOPS12 disease development, progression and could potentially lead to new therapies for people affected by MCOPS12. Our developed MSN protocol has the potential to become a perfect tool for various striatal disease and disorder investigations and disease modeling. It also could be used as a pharmaceutical drug screenings platform to target striatal neurons negatively affected by Parkinson’s or Huntington’s diseases

Exploring the interplay between the RNA editing enzyme ADAR1 and innate immune responses in cervical cancer

Development of cervical cancer (CC) is closely linked to persistent infection with HPVs, the most frequent sexually transmitted infectious agents worldwide. Though prophylactic vaccines are available, many people remain unvaccinated and the vaccine does not prevent cancer development in individuals who are already infected. Cancer progression can take 10 to 20 years, reflecting a long-lasting inability of immune responses to eliminate infected and abnormal cells, but also suggesting that there is an ample interval for therapeutic interventions. Among immune evasion mechanisms, ADAR1 may play a role since it senses endogenous double-stranded (ds) RNAs, which may resemble viral structures, and by editing adenosines into inosines, prevents aberrant activation of innate immune pathways (e.g., IFN-I production). In most cancer types, ADAR1 is overexpressed, as tumors exploit its IFN-suppressing activity and ability to edit genes, impacting oncogenes and tumor suppressors. In this project we addressed for the first time the possibility to restore innate immune responses against CC - in particular IFN-I and innate cytotoxic lymphocytes – by manipulating the expression of ADAR1. Our main observations were: i) an increased ADAR1 expression during CC progression; ii) the infiltration of innate lymphocytes (NK cells, ILCs), identified in cervix-derived fresh biopsies; iii) the penetration of NK cells also in 3D-organotypic raft cultures of CC cells; iv) an increased expression of IFN-I and several inflammatory chemokines/cytokines in ADAR1-silenced CC cell lines; v) a potent activation of NK cells treated with conditioned media of ADAR1-silenced cells. These findings suggest that inhibition of ADAR1 expression and/or editing might represent a therapeutic perspective for cervical and other cancers as well

Zn–al layered double hydroxides synthesized on aluminum foams for fluoride removal from water

Fluoride excess in water represents an environmental issue and a risk for human health since it can cause several diseases, such as fluorosis, osteoporosis, and damage of the nervous system. Layered double hydroxides (LDHs) can be exploited to remove this contaminant from water by taking advantage of their high ion-exchange capability. LDHs are generally mixed with polluted water in the form of powders, which then cause the problem of uneasy separation of the contaminated LDH sludge from the purified liquid. In this work, Zn–Al LDH films were directly grown in situ on aluminum foams that acted both as the reactant and substrate. This method enabled the removal of fluoride ions by simple immersion, with ensuing withdrawal of the foam from the de-contaminated water. Different LDH synthesis methods and aluminum foam types were investigated to improve the adsorption process. The contact time, initial fluoride concentration, adsorbent dosage, and pH were studied as the parameters that affect the fluoride adsorption capacity and efficiency. The highest absorption efficiency of approximately 70% was obtained by using two separate growth methods after four hours, and it effectively reduced the fluoride concentration from 3 mg/L to 1.1 mg/L, which is below the threshold value set by WHO for drinking water

Two different acid oxidation syntheses to open C60 fullerene for heavy metal detection

Graphene oxide quantum dots (GOQDs) can be synthesized through a large variety of synthesis methods starting from different carbon allotropes such as nanotubes, graphite, C60 and exploiting various synthesis and reactions. These different approaches have great influence on the properties of the obtained materials, and, consequently, on the potential applications. In this work, Buckminster C60 fullerene has been used to prepare unfolded fullerene nanoparticles (UFNPs) via two distinct synthesis methods namely: Hummer and H2 SO4 + HNO3 solution. The different characteristics of the final materials and the different response in the presence of heavy metal ions have been investigated in view of sensing applications of water contamination

Cr segregation and impact fracture in a martensitic stainless steel

The fracture surfaces of a 10.5 wt.% Cr martensitic stainless steel broken in Charpy tests have been investigated through X-ray photoelectron spectroscopy (XPS). The specimens have been examined in two different conditions: as-quenched and heat treated for 10 h at 700°C. The trends of Fe/Cr ratio vs. test temperature are similar to the sigmoidal curves of absorbed energy and, after both ductile and quasi-cleavage brittle fractures, such ratio is always significantly lower than the nominal value of the steel chemical composition. Cr segregation does not occur on a macroscopic scale but takes place in microscopic zones which represent weaker spots in the steel matrix and a preferred path for moving cracks. Small area (diameter 300 μm) XPS measurements evidenced a higher density of such microscopic zones in the inner part of probes; this is explained by the different diffusion length of Cr atoms in the external and inner parts during quenching from austenitic field which has been calculated through FEM simulations. No significant differences of Cr concentration were observed in fracture surfaces of probes with and without heat treatment. The results highlight how Cr segregation plays a role not only in the intergranular mode of fracture but also in the quasi-cleavage and ductile ones

Correlation between the bath composition and nanoporosity of DC-electrodeposited Ni-Fe alloy

The outstanding mechanical strength of as-deposited DC-electrodeposited nanocrystalline (nc) Ni-Fe alloys has been the subject of numerous researches in view of their scientific and practical interest. However, recent studies have reported a dramatic drop in ductility upon annealing above 350°C, associated with a concomitant abnormal rapid grain growth. The inherent cause has been ascribed to the presence of a detrimental product or by product in the bath, which affects either the microstructure or causes defects in the concentration and/or distribution of the as-deposited films. The present work has been inspired by the observed abnormal behaviour of annealed electrodeposited nc Ni-Fe alloy, which has here been addressed by considering the relationship between the composition of the bath (iron-chloride, nickel-sulphate solution, saccharin and ascorbic acid) and deposition defects (e.g. grain boundary pores) in the case of an nc Ni-Fe (Fe 48 wt%) alloy. The current investigations have included X-ray photoelectron spectroscopy (XPS), field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) in both as-deposited and post-annealed conditions (300°C–400°C). XPS depth profiling with Ar ion sputtering showed a significant amount of C and O impurities entrapped in the foils during deposition. As such impurities are often overlooked in common analytical techniques, new scenarios may need to be rationalised to explain the observed drop in tensile ductility of the as-deposited Ni-Fe alloys

Discriminating between different heavy metal ions with fullerene-derived nanoparticles

A novel type of graphene-like nanoparticle, synthesized by oxidation and unfolding of C-60 buckminsterfullerene fullerene, showed multiple and reproducible sensitivity to Cu2+, Pb2+, Cd2+, and As(III) through different degrees of fluorescence quenching or, in the case of Cd2+, through a remarkable fluorescence enhancement. Most importantly, only for Cu2+ and Pb2+, the fluorescence intensity variations came with distinct modifications of the optical absorption spectrum. Time-resolved fluorescence study confirmed that the common origin of these diverse behaviors lies in complexation of the metal ions by fullerene-derived carbon layers, even though further studies are required for a complete explanation of the involved processes. Nonetheless, the different response of fluorescence and optical absorbance towards distinct cationic species makes it possible to discriminate between the presence of Cu2+, Pb2+, Cd2+, and As(III), through two simple optical measurements. To this end, the use of a three-dimensional calibration plot is discussed. This property makes fullerene-derived nanoparticles a promising material in view of the implementation of a selective, colorimetric/fluorescent detection system