Electrodeposition of lead dioxide on Fe electrode: application to the degradation of Indigo Carmine dye

Journal of Applied Electrochemistry - The modification of an iron electrode was carried out according to the following two steps. In a first step, a cathodic reduction is performed to form a film...     

Biosorption of chromium (VI) from aqueous solution by seed powder of prickly pear (Opuntia ficus indica L.) fruits

ABSTRACT

The solid residue of the cold press oil extraction from prickly pear (Opuntia ficus indica L.) fruit seeds was evaluated as a low-cost biosorbent for biosorption of Cr(VI) from aqueous solutions. Batch experiments were conducted as a function of initial pH, contact time, biosorbent dose, initial Cr(VI) concentration, and temperature. Biosorption was highly pH-dependent and found to be maximum at pH 1.0. Langmuir and Freundlich equations fitted very well with experimental data. The maximum monolayer adsorption capacity was 19.61 mg/g at 298 K and pH 1.0. Biosorption kinetics was controlled by the pseudo-second-order model. Thermodynamic parameters indicated that biosorption of Cr(VI) was a spontaneous, favorable and endothermic process. The activation energy was found to be 40.68 kJ.mol^?1.     

Gastric Adenocarcinomas and Signet-Ring Cell Carcinoma: Unraveling Gastric Cancer Complexity through Microbiome Analysis—Deepening Heterogeneity for a Personalized Therapy

Gastric cancer (GC) is the fifth most prevalent cancer worldwide and the third leading cause of global cancer mortality. With the advances of the omic studies, a heterogeneous GC landscape has been revealed, with significant molecular diversity. Given the multifaceted nature of GC, identification of different patient subsets with prognostic and/or predictive outcomes is a key aspect to allow tailoring of specific treatments. Recently, the involvement of the microbiota in gastric carcinogenesis has been described. To deepen this aspect, we compared microbiota composition in signet-ring cell carcinoma (SRCC) and adenocarcinoma (ADC), two distinct GC subtypes. To this purpose, 10 ADC and 10 SRCC and their paired non-tumor (PNT) counterparts were evaluated for microbiota composition through 16S rRNA analysis. Weighted and unweighted UniFrac and Bray–Curtis dissimilarity showed significant community-level separation between ADC and SRCC. Through the LEfSe (linear discriminant analysis coupled with effect size) tool, we identified potential microbial biomarkers associated with GC subtypes. In particular, SRCCs were significantly enriched in the phyla Fusobacteria, Bacteroidetes, Patescibacteria, whereas in the ADC type, Proteobacteria and Acidobacteria phyla were found. Overall, our data add new insights into GC heterogeneity and may contribute to deepening the GC classification.     

Vocal production in postpartum dairy cows: Temporal organization and association with maternal and stress behaviors

Mammalian vocalizations can encode contextual information in both the spectrographic components of their individual vocal units and in their temporal organization. Here we observed 23 Holstein-Friesian dairy cows immediately after birth during interactions with their calf and when their calf was separated to the other side of a fence line. We investigated whether the vocalizations emitted in these postpartum contexts would vary temporally. We also described the maternal and stress behaviors preceding and following postpartum vocal production using kinematic diagrams and characterized call sequence structure. The kinematic diagrams highlight the disruption of maternal responses caused by calf separation and show that behavioral and vocal patterns varied according to the cows' emotional states and proximity to the calf in both contexts. During calf interactions, cows mainly produced closed-mouth calls simultaneous to licking their calf, whereas an escalation of stress responses was observed during calf separation, with the cows approaching the fence line, becoming alert to the calf, and emitting more mixed and open-mouth calls. Call sequences were similarly structured across contexts, mostly containing repetitions of a single call type, with a mean interval of 0.57 s between calls and a greater cumulative vocalization duration, attributed to an increased number of vocal units per sequence. Overall, calf separation was associated with a greater proportion of calls emitted as a sequence (inverse of single isolated calls), a shorter interval between separate call sequences, and a greater number of vocal units per sequence, compared with calf interactions. These temporal vocal features varied predictably with the high stress expression from cows during calf separation and may represent temporal modulations of emotional expression. Despite the noisy farm soundscape, empirical call type and temporal vocal features were easy to measure; thus, findings could be applied to future cattle studies wishing to analyze vocalizations for on-farm welfare assessments.     

Pectins from Aloe Vera: Extraction and production of gels for regenerative medicine

Extraction, purification, and gel preparation of Aloe Vera pectin and the evaluation of the biocompatibility of the pectin gels were studied, considering as end use as implantable materials for regenerative medicine. A. Vera was chosen as source of pectin, as this pectin was described to possess high molecular weight and a low degree of esterification. As the properties of pectins are strictly dependent upon the extraction methods in combination with the natural source, the extraction method was modified in order to optimize the yield of the final product, its purity, the duration of the process and the selection of non‐toxic chemical reagents. Changing the experimental conditions resulted in four different extraction processes and products with different physical and chemical characteristics. The optimal extraction resulted to be the process: with enzimatic deactivation by microwave and the use of sodium citrate as chelating agent the molecular weight of the pectin extracted was estimated to be 118 kDa and the 2.93% esterification degree. Cytocompatibility of pectin gels, prepared by ionotropic gelation, showing an improved cell adhesion if compared to commercial pectin. The results suggest that the extracted A. Vera pectins possess interesting properties to be exploited for the production of mechanically stable gels by ionotropic gelation and high rhamnose content matrices for application in regenerative medicine. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39760.     

Making the Bend: DNA Tertiary Structure and Protein-DNA Interactions

DNA structure functions as an overlapping code to the DNA sequence. Rapid progress in understanding the role of DNA structure in gene regulation, DNA damage recognition and genome stability has been made. The three dimensional structure of both proteins and DNA plays a crucial role for their specific interaction, and proteins can recognise the chemical signature of DNA sequence (“base readout”) as well as the intrinsic DNA structure (“shape recognition”). These recognition mechanisms do not exist in isolation but, depending on the individual interaction partners, are combined to various extents. Driving force for the interaction between protein and DNA remain the unique thermodynamics of each individual DNA-protein pair. In this review we focus on the structures and conformations adopted by DNA, both influenced by and influencing the specific interaction with the corresponding protein binding partner, as well as their underlying thermodynamics.     

Polycyclic aromatic hydrocarbon (PAH) content of soil and olives collected in areas contaminated with creosote released from old railway ties

Simple sample preparation procedures involving sonication and solid phase extraction (SPE), followed by reversed-phase high performance liquid chromatography (HPLC) and spectrofluorometric detection, were used to analyse polycyclic aromatic hydrocarbons (PAHs) in soil and olives collected in areas contaminated with creosote-treated railway ties. Very high PAH contents (with amounts ranging from 114.7 to 2157.2 and from 167.3 to 3121.8 microg kg(-1) dry weight for total light PAHs and total heavy PAHs, respectively) were found in soil sampled up to 1 m from the source of contamination. The PAH load decreased rapidly with the distance from the railway ties. High amounts of light PAHs, up to 6359.9 microg kg(-1), were also found in oil extracted from olives collected in a rural area where old railway ties were stored. No appreciable transfer of heavy PAHs and benzo[a]pyrene was observed in oil samples.