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61.
The aim of this work was to study the biological effects of four monoterpenes, i.e. α-pinene, β-pinene, 3-carene and D-limonene present in the wastewater of a citrus transformation factory. The study was carried out by exposing V79 Chinese hamster cells to single terpene or to the mixture of four terpenes at concentrations corresponding to those in the wastewater evaluated by head space solid phase micro extraction and gas chromatography (HS-SPME-GC) analyses. Treatments with single or combined terpenes similarly affected cell vitality, but only the combined treatments induced the 6-thioguanine resistant mutants. Moreover the photocatalytic degradation of the four terpenes was successfully achieved with the photocatalyst TiO(2) Degussa P25 in both the actual effluent and in synthetic solutions.  相似文献   
62.
Systemic lupus erythematosus (SLE) is a chronic, systemic autoimmune disease with a wide range of clinical expressions. The kidney is often affected, usually within 5 years of the onset of SLE, and lupus nephropathy (LN) carries a high risk for increased morbidity. The clinical heterogeneity of the disease is accompanied by complex disturbances affecting the immune system with inflammation and tissue damage due to loss of tolerance to nuclear antigens and the deposition of immune complexes in tissues. Several studies have reported that in human SLE, there is an important role of the Type-I-interferons (INF) system suggested by the upregulation of INF-inducible genes observed in serial gene expression microarray studies. This review aims to describe the transduction pathways of Type-I-interferons, in particular INFα, and its immune-regulatory function in the pathogenesis of SLE and, in particular, in LN. In addition, recent novelties concerning biologic therapy in LN will be discussed.  相似文献   
63.
Varicocele (VC) is the most common abnormality identified in men evaluated for hypofertility. Increased levels of reactive oxygen species (ROS) and reduced antioxidants concentrations are key contributors in varicocele-mediated hypofertility. Moreover, inflammation and alterations in testicular immunity negatively impact male fertility. In particular, NLRP3 inflammasome activation was hypothesized to lead to seminal inflammation, in which the levels of specific cytokines, such as IL-1β and IL-18, are overexpressed. In this review, we described the role played by oxidative stress (OS), inflammation, and NLRP3 inflammasome activation in VC disease. The consequences of ROS overproduction in testis, including inflammation, lipid peroxidation, mitochondrial dysfunction, chromatin damage, and sperm DNA fragmentation, leading to abnormal testicular function and failed spermatogenesis, were highlighted. Finally, we described some therapeutic antioxidant strategies, with recognized beneficial effects in counteracting OS and inflammation in testes, as possible therapeutic drugs against varicocele-mediated hypofertility.  相似文献   
64.
Age related bone diseases such as osteoporosis are considered among the main causes of reduced bone mechanical stability and bone fractures. In order to restore both biological and mechanical function of diseased/fractured bones, novel bioactive scaffolds that mimic the bone structure are constantly under development in tissue engineering applications. Among the possible candidates, chitosan-based thermosensitive hydrogel scaffolds represent ideal systems due to their biocompatibility, biodegradability, enhanced antibacterial properties, promotion of osteoblast formation and ease of injection, which makes them suitable for less invasive surgical procedures. As a main drawback, these chitosan systems present poor mechanical performance that could not support load-bearing applications. In order to produce more mechanically-competent biomaterials, the combined addition of hydroxyapatite and carbon nanotubes (CNTs) is proposed in this study. Specifically, the aim of this work is to develop thermosensitive chitosan hydrogels containing stabilised single-walled and multi-walled CNTs, where their effect on the mechanical/physiochemical properties, calcium deposition patterns and ability to provide a platform for the controlled release of protein drugs was investigated. It was found that the addition of CNTs had a significant effect on the sol–gel transition time and significantly increased the resistance to compression for the hydrogels. Moreover, in vitro calcification studies revealed that CNTs played a major role in the spatial arrangements of newly formed calcium deposits in the composite materials studied, suggesting that they may have a role in the way the repair of fragile and/or fractured bones occurs in vivo.  相似文献   
65.
66.
The role of excess photon energy on charge generation efficiency in bulk heterojunction solar cells is still an open issue for the organic photovoltaic community. Here, the spectral dependence of the internal quantum efficiency (IQE) for a poly[2,6‐(4,4‐bis‐(2‐ethylhexyl)‐4H‐cyclopenta[2,1‐b;3,4‐b]­dithiophene)‐alt‐4,7‐(2,1,3‐benzothiadiazole)]:6,6‐phenyl‐C61‐butyric acid methyl ester (PCPDTBT:PC60BM)‐based solar cell is derived combining accurate optoelectronic characterization and comprehensive optical modeling. This joint approach is shown to be essential to get reliable values of the IQE. Photons with energy higher than the bandgap of the donor material can effectively contribute to enhance the IQE of the solar cell. This holds true independently of the device architecture, reflecting an intrinsic property of the active material. Moreover, the nanomorphology of the bulk heterojunction plays a crucial role in determining the IQE spectral dependence: the coarser and more crystalline, the lesser the gain in IQE upon high energy excitation.  相似文献   
67.
Pseudoxanthoma elasticum (PXE) is a genetic disorder associated to mutations in the ABCC6 gene; however, the pathogenetic mechanisms leading to elastic fibre calcifications and to clinical manifestations are still unknown. Dermal fibroblasts, directly involved in the production of the extracellular milieu, have been isolated from healthy subjects and from patients affected by PXE, cultured in vitro and characterized for their ability to produce reactive oxygen species, for structural and functional properties of their cell membranes, for changes in their protein profile. Data demonstrate that oxidative stress has profound and endurable consequences on PXE fibroblast phenotype being responsible for: reduced levels of global DNA methylation, increased amount of carbonylated proteins and of lipid peroxidation products, altered structural properties of cell membranes, modified protein expression. Data shed new light on the pathogenetic pathways in PXE, by identifying a network of proteins affecting elastic fibre calcification through inefficient vitamin K recycling, and highlight the role of differentially expressed proteins as targets for validating the efficacy of future therapeutic strategies aiming to delay and/or revert the pathologic phenotype of PXE fibroblasts. Moreover, data open new perspectives for investigating PXE-like phenotypes in the absence of ABCC6 mutations.  相似文献   
68.
A study was carried out on the presence of Anisakis and Hysterothylacium larvae in fish and cephalopods caught in Sardinian waters. A total of 369 specimens of 24 different species of teleosts and 5 species of cephalopods were collected from different fishing areas of Sardinia. Larvae were detected and isolated by both visual inspection and enzymatic digestion. These methods allowed Anisakis type I and type II third-stage larvae and Hysterothylacium third- and fourth-stage larvae to be detected. The prevalence, mean intensity, and mean abundance were calculated. The results obtained showed the highest prevalence of Anisakidae in Zeus faber (100%) and of Anisakis in Micromesistius poutassou (87.5%). The highest prevalence of Anisakis type I larvae was in M. poutassou (81.2%), and that of Anisakis type II larvae was in Todarodes sagittatus (20%). The highest values for prevalence, mean intensity, and mean abundance for Hysterothylacium were found in Z. faber. These prevalences and the mean intensity and abundance were higher than those reported by different authors in other Mediterranean areas. This may be because the enzymatic digestive method used in this research resulted in higher recovery levels. The data suggest that Sardinia may be a high-risk area for zoonotic diseases and that measures such as information campaigns, aimed at both sanitary service personnel and consumers, should be employed to limit the spread of such zoonosis.  相似文献   
69.
The capability of X-ray photoelectron spectroscopy, XPS or ESCA, in analysing oxidation states and measuring the concentration of elements present in air pollution particulates collected on membrane filters is evaluated. Semi-quantitative data are compared with those from XRF and wet chemical analysis. Differences of about a factor of 2.0–2.5 are found which are critically discussed in relation to particle size and the distribution of ionic species. The importance of intrinsic properties of matrix materials and instrumental factors is also discussed.  相似文献   
70.
Feed production systems should consider more sustainable solutions to reduce the pressure on earth's finite resources. In this work, we investigated the effect of microencapsulated condensed tannins (MCTs)-enhanced diet on the cow milk characteristics. The diet reduced the urea content, while preserved and the n-3 and n-6 portion of fatty acids. Aside from the rising of vitamin C level, MCTs had a negative effect on the amount of B group vitamins. MCTs may be considered a promising feed supplement that offers a good trade-off in terms of milk chemical quality while increasing the environmental sustainability of cattle livestock.  相似文献   
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