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121.
Paola Maura Tricarico Donatella Mentino Aurora De Marco Cecilia Del Vecchio Sabino Garra Gerardo Cazzato Caterina Foti Sergio Crovella Giuseppe Calamita 《International journal of molecular sciences》2022,23(7)
The skin is the largest organ of the human body, serving as an effective mechanical barrier between the internal milieu and the external environment. The skin is widely considered the first-line defence of the body, with an essential function in rejecting pathogens and preventing mechanical, chemical, and physical damages. Keratinocytes are the predominant cells of the outer skin layer, the epidermis, which acts as a mechanical and water-permeability barrier. The epidermis is a permanently renewed tissue where undifferentiated keratinocytes located at the basal layer proliferate and migrate to the overlying layers. During this migration process, keratinocytes undertake a differentiation program known as keratinization process. Dysregulation of this differentiation process can result in a series of skin disorders. In this context, aquaporins (AQPs), a family of membrane channel proteins allowing the movement of water and small neutral solutes, are emerging as important players in skin physiology and skin diseases. Here, we review the role of AQPs in skin keratinization, hydration, keratinocytes proliferation, water retention, barrier repair, wound healing, and immune response activation. We also discuss the dysregulated involvement of AQPs in some common inflammatory dermatological diseases characterised by skin barrier disruption. 相似文献
122.
Use of β-hydroxyacyl-CoA-dehydrogenase (HADH) activity to differentiate frozen from unfrozen fish and shellfish 总被引:1,自引:0,他引:1
Manuela Fernández Sergio Mano Gonzalo D. García de Fernando Juan A. Ordóñez L. Hoz 《European Food Research and Technology》1999,209(3-4):205-208
Further work on an enzymic method to differentiate frozen from unfrozen fish and shellfish is reported. The method is based
on the release of the β-hydroxyacyl-CoA-dehydrogenase (HADH) from mitochondria during freezing. Enzymic activity was evaluated
in fresh and frozen thawed samples from sole (Solea solea), sea bream (Pagellus centrodontus), hake (Merluccius merluccius), gilt headed bream (Sparus aurata), sea bass (Dicentrarchus labrax), salmon (Salmo salar), prawn (Penaeus japonicus) and Norwegian lobster (Nephrops norvegicus). Changes in the HADH activity of fresh and frozen thawed samples were compared after freezing at –196 °C for 15 min. Two
values were obtained: U (by dividing: HADH activity of samples frozen at –196 °C, then thawed/HADH activity of unfrozen samples) and F (by dividing: HADH activity of samples frozen at –18 °C, thawed, then frozen at –196 °C /HADH activity of samples frozen
at –18 °C, then thawed). Statistical analysis showed significant differences (P≤0.05) between both quotients for gilt headed bream, salmon, sea bream, sole and prawn, and an arbitrary limit was set at
2 to differentiate frozen thawed from unfrozen samples. The application of this limit made it possible to discriminate the
unfrozen from the frozen thawed state of around 90% of the total samples analysed. Best results were obtained for prawn (100%
of samples differentiated). In the present paper, a laboratory routine is proposed based on the comparison of the HADH activity
of a sample analysed straight away and that of a sample frozen at –196 °C and then thawed. The reported method is simple
and fast. The entire laboratory procedure can be performed in 45 min.
Received: 20 July 1998 / Revised version: 2 November 1998 相似文献
123.
The modern fruit juice industry needs their products to be characterized by high-quality attributes to meet consumers’ expectation. In this view, the composition of 26 Italian commercial apricot juices obtained from organic, integrated and conventional agriculture was analysed for carbohydrates, organic acids, amino acids, phenolic compounds and furanic compounds by high-performance liquid chromatography (HPLC). The content of 5-hydroxymethylfurfural in apricot juices (range 0.1–18 mg/l) was within the regulatory limit of 20 mg/l. The lack of furanic compounds in apricot fresh fruits confirmed their importance as quality markers of heating condition during processing and storage of fruit juices. Univariate analysis disclosed some significant differences among the composition of the apricot juices in terms of glucose, fructose, malic acid, glycine, chlorogenic acid, rutin, and a∗-parameter (redness). Principal component analysis on chemical composition of apricot juices resulted in two principal components (PCs) that accounted for 66% of the total variance. Organic apricot juices showed some separation from the other juices, whereas a lack of distinction between integrated and conventional juices appeared. 相似文献
124.
Flavonoids and saponins from common beans have been widely studied due to their bioactivity. This research evaluated the effect of germination of black beans (Phaseolus vulgaris L.) on the antioxidant capacity and antiproliferative activity against cancer cell lines of saponins and flavonoids extracted from seed coats, cotyledons and sprouts. Principal component analysis was performed to achieve punctual associations between the black bean saponins and flavonoids concentrations to the antioxidant capacity and the antiproliferative activities. Total phenolic content and antioxidant capacity of extracts were higher when obtained from seed coats, mainly from the 3rd germination day. The extracts obtained from seed coats after 3 and 5 germination days inhibited all cancer cell lines proliferation with no cytotoxicity against control cells. Genistein was related with the activity against mammary cancer cells but flavonols and group B saponins were more related with hepatic and colon cancers. Non-glycosilated flavonols were related with antioxidant capacity. 相似文献
125.
Suarez Cristian Repizo Guillermo Espariz Martín Blancato Víctor Magni Christian Alarcón Sergio 《Food science and biotechnology》2012,21(2):603-606
The aim of this study was to isolate and identify strains of Enterococcus from commercial cheeses and then analyze their abilities to produce biogenic amines. The genotypic variability, studied by
randomly amplified polymorphic DNA (RAPD)-PCR, showed a high degree of homogeneity among enterococcal strains. Afterward,
genotypic analysis indicated that all strains contain genes encoding a tyrosine decarboxylase. Our results indicate that a
potential health risk exists if the enterococcal strains are able to survive the pasteurization of milk or appear as post-pasteurization
contaminants. These results highlight the importance of the hazard analysis and critical control point (HACCP) to minimize
the risk of hazards associated with post-contamination during cheese elaboration 相似文献
126.
A specially designed electro-cross-flow nanofiltration (NF) membrane system was used for this investigation. To enhance the rejection of arsenic ionic species like H2AsO4−, a NF membrane having a negative surface charge was fabricated via the interfacial polymerization process. The membrane was characterized by SEM, AFM, surface charge density, molecular weight cut-off (MWCO), total and skin thickness and pure water flux. The parameters that affected the rejections of As(III) and As(V) were studied; they included the initial arsenic concentration, the applied potential, pH of the feed, the cross-flow filtration pressure and the presence of different salts in the feed. Among those parameters, the pH of the feed greatly affected As(V) rejection; As(V) ([As(V)]o = 1000 ppb) rejection was increased from 72.3 to 98.5% when pH of the feed was changed from 3.0 to 10.0. This might be due to the fact that higher pH enhanced the formation of negative divalent anion like HAsO42− which should be rejected more effectively by the negative surface charge of the NF membrane. Beside the effect of the negative surface charge of the membrane, applied potential increased the As(V) rejection by 48.2% when the applied potential was increased from 0 to 2.0 V for a feed containing 1000 ppb initially. For the same change of applied potential rejection of As(III) was increased from 52.3 to 70.4%; this might be the result of the formation of anionic species like H2AsO3− from the neutral molecule of H3AsO3 by the applied potential. 相似文献
127.
Synthesis and characterization of the polyols by air oxidation of soybean oil and its effect on the morphology and dynamic mechanical properties of poly(vinyl chloride) blends
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Pedro A. Ourique Jérôme M. L. Gril Gaëlle W. Guillaume Cesar H. Wanke Sergio G. Echeverrigaray Otávio Bianchi 《应用聚合物科学杂志》2015,132(24)
The use of natural additives, with low toxicity and good compatibility, for PVC is becoming increasingly attractive. In this study, soybean oil additives were prepared by air oxidation reactions and blending with PVC. The oxidation reaction produced a significant increase in the number of hydroxyl groups in soybean oil; however, this kind of reaction results in the formation of a heterogeneous structure due to free radical reactions in the medium. The oxidized soybean oil improved the compatibility with PVC due to an increase in the number of polar groups, such as hydroxyls, and thus a reduction in the amount of atactic polymer was observed. Furthermore, an increase in the molecular weight of the oxidized oil, as well as large amounts of polar groups contributes to reducing the migration of oil in the PVC. Regarding the crystallinity of PVC, the use of pure and oxidized soybean oil causes small changes in the crystalline phase of the polymer. Oxidized soybean oil has great potential for usage as a secondary plasticizer for PVC. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42102. 相似文献
128.
Promising curaua fiber‐reinforced polyester composite for high‐impact ballistic multilayered armor
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Sergio Neves Monteiro Fabio de Oliveira Braga Edio Pereira Lima Luis Henrique Leme Louro Jaroslaw Wieslaw Drelich 《Polymer Engineering and Science》2017,57(9):947-954
A typical multilayered armor system (MAS) is composed of a harder front ceramic tile, which is able to erode heavy ammunition, such as the 7.62 mm bullet, followed by a second layer to further reduce the impact energy. Aramid fabric is a common choice for the second layer. In the present work, polyester matrix composites reinforced with 10 to 30 vol% of curaua fibers, despite having much lower strength and stiffness than aramid fabric, displayed similar trauma indentation in a standard clay witness simulating the human body. Impedance matching and scanning electron microscopy analyses suggest effective energy absorption through ceramic fragment capture by curaua composites. Additionally, because of the high cost of aramid fabric, a full MAS with curaua fiber composite is much cheaper than a MAS composed of aramid fabric. Taking into consideration, both the economical and environmental advantages of natural fibers, it is concluded that curaua fiber‐reinforced polyester composite could replace aramid fabric as the second layer in MASs for personal ballistic protection. POLYM. ENG. SCI., 57:947–954, 2017. © 2016 Society of Plastics Engineers 相似文献
129.
Catanozi S Rocha JC Passarelli M Mesquita CH Suguiama VY Guzzo ML dos Santos Filho A Quintão EC Nakandakare ER 《Lipids》2006,41(7):663-668
Dyslipoproteinemia of the Nagase analbuminemic rat (NAR) is characterized by elevated concentrations of VLDL and LDL attributed
to increased rates of liver lipoprotein synthesis. Increased lysophosphatidylcholine (LPC) in NAR HDL has been attributed
to high plasma LCAT activity. We show here that, as compared with Sprague-Dawley rats (SDR), NAR plasma triacylglycerol (TAG),
total cholesterol (TC), HDL TAG, protein, total phospholipids (PL), LPC, and PS are increased. These alterations rendered
the NAR HDL particle more susceptible to the activity of the enzyme hepatic lipoprotein lipase (HL), which otherwise was unaltered
in our study. Fractional catabolic rates in blood of the autologous 125I-apoHDL (median and lower quartile values), were, respectively, 0.231 and 1.645 (n=10) in NAR as compared with 0.140 and 0.109 (n=10) in SDR (P=0.012), corresponding to synthesis rates of HDL protein of 89.8±33.7 mg/d in NAR and 17.4±6.5 mg/d in SDR (P=0.0122). Furthermore, Swiss mouse macrophage free-cholesterol (FC) efflux rates, measured as the percent [14C]-cholesterol efflux/6 h, were 8.2±2.3 (n=9) in NAR HDL and 11.2±3.2 (n=10) in SDR HDL (P=0.03). Therefore, in NAR the modification of the HDL composition slows down the cell FC efflux rate, and together with the
increased rate of plasma HDL metabolism influences the reverse cholesterol transport system. 相似文献
130.
Discovery of a Short‐Chain Dehydrogenase from Catharanthus roseus that Produces a New Monoterpene Indole Alkaloid
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Dr. Anna K. Stavrinides Dr. Evangelos C. Tatsis Dr. Thu‐Thuy Dang Dr. Lorenzo Caputi Dr. Clare E. M. Stevenson Dr. David M. Lawson Dr. Bernd Schneider Prof. Sarah E. O'Connor 《Chembiochem : a European journal of chemical biology》2018,19(9):940-948
Plant monoterpene indole alkaloids, a large class of natural products, derive from the biosynthetic intermediate strictosidine aglycone. Strictosidine aglycone, which can exist as a variety of isomers, can be reduced to form numerous different structures. We have discovered a short‐chain alcohol dehydrogenase (SDR) from plant producers of monoterpene indole alkaloids (Catharanthus roseus and Rauvolfia serpentina) that reduce strictosidine aglycone and produce an alkaloid that does not correspond to any previously reported compound. Here we report the structural characterization of this product, which we have named vitrosamine, as well as the crystal structure of the SDR. This discovery highlights the structural versatility of the strictosidine aglycone biosynthetic intermediate and expands the range of enzymatic reactions that SDRs can catalyse. This discovery further highlights how a sequence‐based gene mining discovery approach in plants can reveal cryptic chemistry that would not be uncovered by classical natural product chemistry approaches. 相似文献