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Abstract

Systemic sclerosis (SSc) is a multisystem autoimmune disease: characterised from the clinical side by progressive vasculopathy and fibrosis of the skin and different organs and from the biochemical side by fibroblast deregulation with excessive production of collagen and increased expression of nicotinamide adenine dinucleotide phosphate oxidase 4 (NOX4). The latter contributes to an overproduction of reactive oxygen species that through an autocrine loop maintains NOX4 in a state of activation. Reactive oxygen and nitrogen species are implicated in the origin and perpetuation of several clinical manifestations of SSc having vascular damage in common; attempts to dampen oxidative and nitrative stress through different agents with antioxidant properties have not translated into a sustained clinical benefit. Objective of this narrative review is to describe the origin and clinical implications of oxidative and nitrative stress in SSc, with particular focus on the central role of NOX4 and its interactions, to re-evaluate the antioxidant approaches so far used to limit disease progression, to appraise the complexity of antioxidant treatment and to touch on novel pathways elements of which may represent specific treatment targets in the not so distant future.  相似文献   
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Recent analyses of internet search volume hypothesized a decline of public interest toward themes related to environment, biodiversity conservation and fishery. These analyses were based on Google Trends, which is a measure of how frequently a term is searched in Google, in proportion to the total of searches performed. Google Trends is a measure of relative search, and this may make difficult assessing temporal trends. I evaluated whether relative declines in internet search volumes represent genuine decline in interest toward environmental-related themes, by comparing trends of terms representing various themes, including environment, computer science, other disciplines (astrophysics) and leisure. Similar values of relative decline were detected for environmental terms, for computer science terms, and for other scientific disciplines. Conversely, an increase was observed for leisure related terms. This suggests that interest toward the environment is not truly decreasing. The apparent decline of environmental and scientific terms is most likely caused by the increasing use of internet for aims unrelated to science and technology, such as leisure. Internet search tools are a powerful source of information, but users should be aware of the complexity of analysing their data: using unrelated terms as benchmark may help to identify genuine trends.  相似文献   
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Traditionally the hERG1 potassium channel has been known to have a fundamental role in membrane excitability of several mammalian cells including cardiac myocytes. hERG1 has recently been found to be expressed in non-excitable cancer cells of different histogenesis, but the role of this channel in cancer biology is unknown. Results form recent studies on the effect hERG1 inhibition in some breast cancer cells are controversial as it can lead to apoptosis or protect against cell death. Nevertheless, these data suggest that the hERG1 channel could have an important role in cancer biology. Here we report the effects of hyperstimulation of hERG1 channel in human mammary gland adenocarcinoma-derived cells. Application of the hERG1 activator, the diphenylurea derivative NS1643, inhibits cell proliferation irreversibly. This event is accompanied by a preferential arrest of the cell cycle in G0/G1 phase without the occurrence of apoptotic events. Consequently, cells responded to NS1643 by developing a senescence-like phenotype associated with increased protein levels of the tumor suppressors p21 and p16INK4a and by a positive β-galactosidase assay. These data suggest that prolonged stimulation of the hERG1 potassium channel may activate a senescence program and offers a compelling opportunity to develop a potential antiproliferative cancer therapy.  相似文献   
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Predictive potential distribution modeling is crucial in outlining habitat usage and establishing conservation management priorities. In this paper we provide detailed data on the distribution of the Caucasian rock agama Para- laudakia caucasia, and use species distribution models (MAXENT) to evaluate environmental suitability and potential distribution at a broad spatial scale. Locality data on the distribution of P. caucasia have been gathered over nearly its entire range by various authors from field surveys. The distribution model ofP caucasia showed good performance (AUC = 0.887), and predicted high suitability in regions mainly located in Tajikistan, north Pakistan, Afghanistan, southeast Turkmenistan, northeast Iran along the Elburz mountains, Transcaueasus (Azerbajan, Armenia, Georgia), northeastern Turkey and northward along the Caspian Sea coast in Daghestan, Russia. The identification of suitable areas for this species will help to assess conservation status of the species, and to set up management programs.  相似文献   
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A biologic, immunologic and molecular characterization of an HHV-6 isolate (BA92) rescued by the peripheral blood mononuclear cells of a child affected by Exanthem subitum is reported. The comparison with the known HHV-6 prototype strains showed that BA92 is indistinguishable from the Z29 isolate, and can be included in the variant B group of HHV-6. A seroepidemiologic analysis of the antibody response to BA92 of normal individuals as well as patients affected by diseases potentially associated to HHV-6 infection has shown an overall seroprevalence of 81%, and that no variations in seroprevalence or in antibody geometric mean titer are observed assaying the sera also against G.S., U1102, or Z29 infected cells, respectively. These findings indicate: (1) HHV-6 infection is widely diffuse in Italy; (2) it is not possible to discriminate between the viral variants by the currently available IF assays, and (3) no conclusions can be drawn on the potential association of HHV-6 with any of the diseases examined.  相似文献   
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The Italian Development Cooperation (DGCS) support the health reform process in Developing Countries, with the aim to provide populations in greatest need with access to decentralized health services. DGCS acts in close coordination with the donor community, United Nations' system and the World Bank, in agreement with sector-wide approach (SWAP) for health sector development. Since malaria control in endemic countries is a relevant component of the health system, DGCS is actively involved in the struggle against malaria in sub-Saharan Africa, supporting control activities and research capability strengthening. The following African countries are presently receiving bilateral support for antimalaria activities: Burkina Faso, Centre de Lutte contre le Paludisme in Ouagadougou; Ethiopia, community-based malaria control in Tigray; Eritrea, malaria control at national level in the framework of the Public Health and Rehabilitation Programme for Eritrea (PHARPE) initiative; Madagascar, malaria surveillance at national level; Tanzania, feasibility study for the support to the national malaria control programme. Support is provided by technical/financial assistance involving Italian academic and research institutions. On the multilateral channel, DGCS has provided regular contribution for WHO's work in malaria control and participates to the WHO Roll Back Malaria initiative. A new commitment to malaria is the trilateral joint scientific endeavour USA-Italy-Burkina Faso for the development and field testing of a candidate vaccine suitable for African populations.  相似文献   
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