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11.
Skin disorders are widespread around the world, affecting people of all ages, and oxidative stress represents one of the main causes of alteration in the normal physiological parameters of skin cells. In this work, we combined a natural protein, fibroin, with antioxidant compounds extracted in water from pomegranate waste. We demonstrate the effective and facile fabrication of bioactive and eco-sustainable films of potential interest for skin repair. The blended films are visually transparent (around 90%); flexible; stable in physiological conditions and in the presence of trypsin for 12 days; able to release the bioactive compounds in a controlled manner; based on Fickian diffusion; and biocompatible towards the main skin cells, keratinocytes and fibroblasts. Furthermore, reactive oxygen species (ROS) production tests demonstrated the high capacity of our films to reduce the oxidative stress induced in cells, which is responsible for various skin diseases.  相似文献   
12.
Neuroblastoma (NB) is a tumor of the developing sympathetic nervous system. Despite recent advances in understanding the complexity of NB, the mechanisms that determine its regression or progression are still largely unknown. Stage 4S NB is characterized by a favorable course of disease and often by spontaneous regression, while progression to true stage 4 is a very rare event. Here, we focused on genomic analysis of an NB case that progressed from stage 4S to stage 4 with a very poor outcome. Array-comparative genomic hybridization (a-CGH) on tumor-tissue DNA, and whole-exome sequencing (WES) on exosomes DNA derived from plasma collected at the onset and at the tumor progression, pointed out relevant genetic changes that can explain this clinical worsening. The combination of a-CGH and WES data allowed for the identification iof somatic copy number aberrations and single-nucleotide variants in genes known to be responsible for aggressive NB. KLRB1, MAPK3 and FANCA genes, which were lost at the time of progression, were studied for their possible role in this event by analyzing in silico the impact of their expression on the outcome of 786 NB patients.  相似文献   
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Three-dimensional submicrometric structures and biomolecular patterns have been fabricated on a porous silicon film by an electron beam-based functionalization method. The immobilized proteins act as a passivation layer against material corrosion in aqueous solutions. The effects'' dependence on the main parameters of the process (i.e., the electron beam dose, the biomolecule concentration, and the incubation time) has been demonstrated.  相似文献   
15.
In this work, the influence of packaging mass transport properties on quality loss of fresh‐cut cauliflower mixtures was addressed. The study was organised in two subsequent experimental steps; first, the selection of micro‐perforated packaging films was carried out by monitoring the package headspace gas concentrations of fresh‐cut white, green cauliflower and roman cabbage. Then, the effects of the barrier properties of the selected micro‐perforated film on shelf life of two different fresh‐cut cauliflower mixtures, stored at 4 ± 1 °C, were addressed. Results suggested that, among the investigated films, the micro‐perforated polymeric matrix with the lowest oxygen transmission rate value showed the best performance as it created the optimum headspace gas composition for each cauliflower variety, as well as, for the product mixtures. The appearance of visible moulds was the factor limiting product shelf life that accounted for about 18 days for both the investigated cauliflower mixtures.  相似文献   
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The objectives of this study were to measure the sorption capacity of a dilute solution of drugs in water on hydrophobic zeolites and to quantify aspects of their adsorption mechanisms for potential use in wastewater remediation. The removal of three drugs, erythromycin (ERY), carbamazepine (CBZ) and levofloxacin (FLX) from water using three organophilic zeolites (Y, mordenite (MOR), ZSM-5) was investigated. Adsorption isotherms show that these three drugs are adsorbed in remarkable amounts by Y. These data were confirmed by thermogravimetric analysis. The presence of these drugs inside the Y cage was revealed by unit cell parameter variations and structural deformations obtained by X-ray structure analyses carried out using the Rietveld method on zeolite after adsorption. Our results indicate that the adsorption properties of zeolitic materials do not only depend on micropore size and that zeolite shape selectivity also depends on structural features which are difficult to determine “a priori”. In order to test the ability of organophilic zeolites in removing drugs from wastewater, the adsorption of ERY, FLX and CBZ on zeolite Y from water samples collected at the outlet of a wastewater treatment plant located in Northern Italy was determined. These drugs were almost completely adsorbed by Y zeolite, confirming that this material is suitable for removing drugs from wastewater.  相似文献   
18.
Capsicum annum cultivars Yellow cayenne, Portafortuna, Idealino, Sole, Duemila, Pellegrino, Fantasia, Loco, and Effix were investigated for their antioxidant properties and foodborne pathogens inhibitory activity. The total phenols, flavonoids, anthocyanins, capsaicinoids, carotenoids, ascorbic acid, and vitamin E content were also determined. Duemila and Portafortuna cultivars showed the highest total phenol content with values of 924.3 and 935.0 mg of chlorogenic acid equivalents/100 g dried weight, respectively. Idealino pepper presented the highest capsaicin content (2932.1 μg/g dried weight). The antioxidant capacity was evaluated by using 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid test, 2,2-diphenyl-1-picrylhydrazyl test, and ferric reducing ability power assay. Both Pellegrino and Idealino samples exhibited a promising radical scavenging ability against 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid radical with IC50 values of 45.2 and 45.7 μg/mL, respectively. All the extracts were able to inhibit the growth of Staphylococcus aureus and Listeria monocytogenes investigated strains. The most active are Effix and Fantasia peppers with minimal inhibitory concentration between 12.5 and 25.0 mg/mL, respectively. Overall, these results support the use of these pepper species as dried extract in food preservation.  相似文献   
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Water is known as one of the main transmission routes of Campylobacter and contributes to increase the number of sporadic infections and outbreaks. Campylobacter jejuni persists in the environment, especially in water, in a viable but non-culturable (VBNC) form that is thought to be a possible cause of water-borne outbreaks. In this study, we evaluated the loss of culturability and viability of 9 C. jejuni strains of clinical origin and one ATCC reference strain when kept at 4 degrees C in artificial sea water (ASW). Culturability was measured as colony-forming units while viability was evaluated by CTC-DAPI double staining and the combined CTC-specific fluorescent antibody technique (CTC-FA). When cultured on Columbia Agar plates, strains exhibited different growth profiles which allowed to classify them into three different groups. Both techniques used to monitor the viability of the bacterial cells showed that C. jejuni strains survived in the VBNC form in the microcosms through a period lasting from 138 to 152 days. The recovery of C. jejuni VBNC forms to culturability, as evidenced by cell division, was obtained by passage in the mouse intestine. Our results indicate that C. jejuni VBNC cells were able to remain in this state for a few months and regain their culturability after in vivo passage depending on their lasting in the VBNC state, which affects the number of respiring bacteria. In fact, the resuscitation was achieved when the number of respiring bacteria became higher than 10(4) cell/ml. Therefore, a relatively high microbial titer of respiring bacteria in the VBNC state seems to be important for the resuscitation and subsequent intestinal colonisation.  相似文献   
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