Coatings based on conducting polymers and functionalized carbon nanotubes obtained by electropolymerization

Nanocomposite films based on polyaniline, functionalized single-walled carbon nanotubes and different dopants were studied. These nanoporous composite films were grown electrochemically from aqueous solutions such that constituents were deposited simultaneously onto substrate electrode.     

Low thermal inactivation of Escherichia coli ATCC 25922 in pineapple,orange and watermelon juices: Effect of a prior acid‐adaptation and of carvacrol supplementation

Past research on the association of natural antimicrobials and low temperatures for fruit juices pasteurization has not targeted acid‐adapted strains which are yet the most relevant strains in these products. We found that previously acid‐adapted Escherichia coli ATCC 25922 cells exhibited an increase of their resistance to thermal inactivation at 55 °C for 5 min both in the presence and absence of carvacrol (30 µL/L). The inactivation of E. coli was more intense in pineapple (pH 3.25) and orange (pH 3.61) juice, than in watermelon juice (pH 5.4). Supplementation of juices with carvacrol decreased the survival of both acid‐adapted and non‐adapted bacterial cells. Our results suggest that the supplementation of fruit juices with natural antimicrobials, such as carvacrol, may contribute to counteract the mild thermal tolerance developed by acid‐adapted bacteria. Given the different properties of fruit juices, such combined treatments need to be developed specifically for each fruit product.

Practical applications

Supplementation of fruit juices with natural antimicrobials has been described to increase the efficiency of microbial mild thermal inactivation treatments. However, its effect on the thermal resistance of acid‐adapted cells has not previously been addressed. We observed that acid adaptation enhances mild thermal tolerance. Our results suggest that natural antimicrobials can effectively counteract the mild thermal tolerance of acid‐adapted cells. The combination of mild temperature treatments and natural antimicrobials is a firm alternative to conventional pasteurization to ensure the safety of fruit juices without affecting their nutritional properties. Moreover, this combined strategy does not require expensive novel technologies or high energy consumption.     

Effect of hydroxyl and nitrate ions on the sorption of ammonium ions by sulphonic cation exchangers

The sorption of ammonium ions and ammonia by the H+ form of sulphonic acid cation exchangers Amberlite 252, Lewatit 2629 and Relite C 360 from a solution containing NH₄NO₃ in the range of 0 to 0.214 equ/L and NH₃ in the range of 0.353 to 0 equ/L was investigated to establish the possibility of their application for the recovery of ammonium from caustic condensate generated in nitrogen fertilizer production. Breakthrough and elution curves were obtained, determining the concentration of ammonium with Nessler's reagent. The sorption of ammonium and ammonia depends on the concentration ratio of ammonia to ammonium nitrate [NH₃]/[NH₄NO₃]. On decreasing [NH₃]/[NH₄NO₃], the concentration ratio of hydroxyl to nitrate ions [OH⁻]/[NO⁻₃] and the effluent pH prior to NH⁺₄ breakthrough also decrease. This results in a decrease in the NH⁺₄ sorption because of a deficiency in the neutralization of hydrogen ions released (ordinary cation-exchange process). Thus, adverse circumstances create an unfavorable medium for NH⁺₄ removal from the caustic condensate. Maximum sorption of NH⁺₄ is attained at [NH₃]/[NH₄NO₃] ∼1.2. A further decrease in [NH₃]/[NH₄NO₃] is followed by a significant decrease in the effluent pH, which leads to an increase in the concentration of protonated sulphonic acid groups (-SO₃H), resulting in a decrease in the ion-exchange ability of the cation exchangers under investigation with respect to NH⁺₄ removal. The concentration (g/L) of NH₄NO₃ in the eluate from the cation-exchanger regeneration, carried out using 0.7 bed volumes (BV) of 20% HNO₃, amounts to 136.7 for Relite C 360, 119.5 for Lewatit K 2629 and 96.7 for Amberlite 252. The content of undamaged beads after 100 cycles (each cycle comprises saturation with caustic condensate, containing ammonia and ammonium, successive regeneration with 20% nitric acid and washing) is from 97 to 99.8%. Resistance to boiling in 20% HNO₃ solution is from 97 to 99.8%. These are applicable for the recovery of NH₄NO₃ from the caustic condensate in the nitrogen fertilizers production, preventing economic damage and environmental contamination from nitrogen compounds.     

The Role of Matrix Metalloproteinases (MMP-8, MMP-9, MMP-13) in Periodontal and Peri-Implant Pathological Processes

Severe periodontitis, a destructive inflammatory disease of the supporting tissues of the teeth, ranks sixth in terms of global spread, affecting about 11% of the population. Metalloproteinases (MMPs) are extracellular matrix (ECM) macromolecules that are important in cellular development and morphogenesis, and they are capable of activating growth factors in their proximity, cell surface receptors, and adhesion molecules. MMPs are part of a major family of zinc-dependent endopeptidases, and their activity is modulated and regulated by certain inhibitors known as tissue metalloproteinase inhibitors (TIMPs). Because type I collagen is the major component of the periodontal extracellular matrix, special attention has been paid to the role of collagenases, especially MMP-8 and MMP-13 and gelatinases, MMP-2 and MMP-9, in periodontal diseases. In fact, MMP-8 (or collagenase 2) is currently one of the most promising biomarkers for periodontitis in oral fluids. Among them, salivary MMP-9 has been shown to be a more sensitive marker for periodontal inflammation during orthodontic treatment, which opens new perspectives in reducing periodontal hazards during such treatments. Both MMP-8 and MMP-9 are extremely valuable diagnostic tools in treating periodontitis, and future studies and healthcare policies should focus on implementing more accessible methods of chairside testing in order to reduce the prevalence of this disease.     

Alteration of Gene and miRNA Expression in Cervical Intraepithelial Neoplasia and Cervical Cancer

Background: Cervical cancer is one of the most common malignancies in women in terms of prevalence and mortality. Cervical cancer has some particularities that distinguish it from any other oncologic pathology: first, it is completely preventable by prompt detection of its precursor, cervical intraepithelial neoplasia (CIN); second, the Human Papillomavirus (HPV) infection is a known etiological agent; third, the mean age at diagnosis is much lower than in other oncologic conditions, as a consequence of the sexually-transmitted HPV. Methods: We evaluated the expression level of several long noncoding RNAs and a microRNA in samples from 30 patients with CIN, 9 with cervical cancer and 38 normal samples using qRT-PCR technology. Results: We observed higher expression levels for MEG3, DAPK1, MLH1 and MALAT1 in CIN samples than in normal samples, whereas TIMP3 and SOX1 had lower expression levels. For cancer samples, DAPK1, MLH1 and MALAT1 had higher expression, and MEG3, TIMP3 and SOX1 had lower expression when compared to normal samples. In the case of CIN versus cancer samples, only MEG3 gene showed a statistically significant difference. The expression of miR-205-5p was lower in both CIN and cancer samples compared to normal samples. Conclusion: Decreased MEG3 expression could be considered an alarm signal in the transition from a premalignant cervical lesion to invasive cancer, while altered expression levels of TIMP3, SOX1, MLH1, MALAT1 and miR-205-5p could serve as early biomarkers in the diagnosis of premalignant cervical lesions. Future studies, including a larger number of patients with CIN, will be of particular importance in validating these observations.     

Legume byproducts as ingredients for food applications: Preparation,nutrition, bioactivity,and techno-functional properties

The demand for high-quality alternative food proteins has increased over the last few decades due to nutritional and environmental concerns, leading to the growing consumption of legumes such as common bean, chickpea, lentil, lupin, and pea. However, this has also increased the quantity of non-utilized byproducts (such as seed coats, pods, broken seeds, and wastewaters) that could be exploited as sources of ingredients and bioactive compounds in a circular economy. This review focuses on the incorporation of legume byproducts into foods when they are formulated as flours, protein/fiber or solid/liquid fractions, or biological extracts and uses an analytical approach to identify their nutritional, health-promoting, and techno-functional properties. Correlation-based network analysis of nutritional, technological, and sensory characteristics was used to explore the potential of legume byproducts in food products in a systematic manner. Flour is the most widely used legume-based food ingredient and is present at levels of 2%–30% in bakery products, but purified fractions and extracts should be investigated in more detail. Health beverages and vegan dressings with an extended shelf-life are promising applications thanks to the techno-functional features of legume byproducts (e.g., foaming and emulsifying behaviors) and the presence of polyphenols. A deeper exploration of eco-friendly processing techniques (e.g., fermentation and ohmic treatment) is necessary to improve the techno-functional properties of ingredients and the sensory characteristics of foods in a sustainable manner. The processing of legume byproducts combined with improved legume genetic resources could enhance the nutritional, functional, and technological properties of ingredients to ensure that legume-based foods achieve wider industrial and consumer acceptance.     

Preparation and cytocompatibility evaluation for hydrosoluble phosphorous acid-derivatized cellulose as tissue engineering scaffold material

Chemical modification of cellulose by phosphorylation enhances its bioactivity and provides new derivatives and materials with specific end uses. In the present study, cellulose derivatized with phosphorous acid was obtained using the reaction of microcrystalline cellulose with phosphorous acid–urea mixture, in molten state, in comparison with others methods that used different solvents and catalysts. Completely water soluble films with a substitution degree close to one were obtained and characterized by analytical and spectral analysis (FT-IR, ³¹P NMR), contact angle, metallographic microscopy and atomic force microscopy (AFM). 31P NMR spectra of derivatized cellulose showed a signal at 2.58 ppm (assigned to P–O–C6) while the doublets at 4.99–5.29 and at 7.38 ppm were assigned to P–O–C2 and P–O–C3, respectively; thus, the formation of monosubstituted phosphorous acid esters of cellulose is advocated. Contact angle measurements showed that the work of adhesion is more important in water than in ethylene glycol, for the phosphorous acid derivatized cellulose. The cytocompatibility of this hydrosoluble derivatized cellulose was tested by direct contact and also by indirect assays on normal human dermal fibroblasts and on osteoblast-like cells (human osteosarcoma). Cell growth on phosphorylated cellulose pellicle and the results from viability assays had shown a good cytocompatibility and lack of toxicity. Phosphorous acid derivatized cellulose would offer a promising biomaterial, useful as scaffolds for new biopolymer composites, and subject for further development as an ionic crosslinker.     

Cellular and Molecular Profiling of Tumor Microenvironment and Early-Stage Lung Cancer

Lung cancers are broadly divided into two categories: non-small-cell lung carcinoma (NSCLC), which accounts for 80–85% of all cancer cases, and small-cell lung carcinoma (SCLC), which covers the remaining 10–15%. Recent advances in cancer biology and genomics research have allowed an in-depth characterization of lung cancers that have revealed new therapy targets (EGFR, ALK, ROS, and KRAS mutations) and have the potential of revealing even more biomarkers for diagnostic, prognostic, and targeted therapies. A new source of biomarkers is represented by non-coding RNAs, especially microRNAs (miRNAs). MiRNAs are short non-coding RNA sequences that have essential regulatory roles in multiple cancers. Therefore, we aim to investigate the tumor microenvironment (TME) and miRNA tumor profile in a subset of 51 early-stage lung cancer samples (T1 and T2) to better understand early tumor and TME organization and molecular dysregulation. We analyzed the immunohistochemistry expression of CD4 and CD8 as markers of the main TME immune populations, E-cadherin to evaluate early-stage epithelial-to-mesenchymal transition (EMT), and p53, the main altered tumor suppressor gene in lung cancer. Starting from these 4 markers, we identified and validated 4 miRNAs that target TP53 and regulate EMT that can be further investigated as potential early-stage lung cancer biomarkers.     

Determination of antibiotics in meat samples using analytical methodologies: A review

Antibiotics are widely used to prevent or treat some diseases in human and veterinary medicine and also as animal growth promoters. The presence of these compounds in foods derived from food-producing animals can be a risk for human health. Consequently, regulatory agencies have set maximum residue limits for antibiotics in food samples. Therefore, the development of novel methodologies for its determination in food samples is required. Specifically, the analysis and quantification of these substances in meat tissues is a challenge for the analytical chemistry research community. This is due to the complexity of the matrix and the low detection limits required by the regulatory agencies. In this sense, a comprehensive review on the development of new sample preparation treatments involving extraction, cleanup, and enrichment steps of antibiotics in meat samples in combination with sensitive and sophisticated determination techniques that have been carry out in the last years is necessary. Therefore, the aim of this work is to summarize the published methodologies for the determination of antibiotics from 2016 until the beginning of the second semester of 2020. The first part of this review includes an introduction about antibiotic families, followed by sample preparation and determination techniques applied to the different families. Finally, a detailed discussion of the current trends and the future possible perspectives in this field are also included.     

Heavy Metals Profile in Honey as a Potential Indicator of Botanical and Geographical Origin

The aim of this study was to determine the heavy metals (As, Cd, Cr, Cu, Fe, Hg, Mn, Ni, Pb, and Zn) from honeys (acacia, sunflower, tilia, and polyfloral) from different counties (Suceava, Botosani, and Vaslui) of the northeast region of Romania. The data were analyzed using principal component analysis and linear discriminate analysis in order to achieve useful models for classification of honeys according to their botanical and geographical origin using the heavy metals content. The heavy metals content can be used as a suitable tool for the classification of honeys according to their botanical origin (80.8% were correctly classified), but not for the geographical origin (only 21.2% were correctly classified). None of the 10 heavy metals analyzed exceeded the maximum allowable level.