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121.
Prof. Piera Scaramella Petri 《Plant biosystems》2013,147(1-2):9-24
Abstract Ultrastructural modifications of plastids in leaflets of Larix decidua and Picea excelsa during sprouting of buds.—Ultrastructural modifications of plastids in leaflets of Larix decidua and Picea excelsa during sprouting of buds kept in different light conditions were observed. While in quiescent buds of both species typical plastids with magnograna are present, fully expanded leaflets kept in the light have plastids with an organized lamellar apparatus. When the buds are kept in darkness the cells of the fully expanded, etiolated leaflets have hardly differentiated plastids with prolamellar bodies partially modified into short tubules and vesicles. Plastids of Picea and Larix buds, in their development, behave almost identically both in darkness and in the light. The differences previously observed in dark grown seedlings of the two species are not to be found in buds. 相似文献
122.
Antimo Cutone Alessandra Frioni Francesca Berlutti Piera Valenti Giovanni Musci Maria Carmela Bonaccorsi di Patti 《Biometals》2014,27(5):807-813
Iron balance is tightly linked to inflammation and it has been demonstrated that many proteins involved in cellular iron management are up- or down-regulated by inflammatory stimuli, ultimately leading to iron retention in the reticuloendothelial system. Ferroportin is a key player in maintenance of correct iron homeostasis, because it is the only known mammalian cellular iron exporter. In this work we show that incubation of THP-1 monocytes/macrophages with lactoferrin prevents the LPS-induced decrease of ferroportin by reducing secretion of IL-6. 相似文献
123.
Hasan Turkez Basak Togar Antonio Di Stefano Numan Taspınar Piera Sozio 《Cytotechnology》2015,67(2):299-309
Sesquiterpenes have attracted much interest with respect to their protective effect against oxidative damage that may be the cause of many diseases including several neurodegenerative disorders and cancer. Our previous unpublished work suggested that cyclosativene (CSV), a tetracyclic sesquiterpene, has antioxidant and anticarcinogenic features. However, little is known about the effects of CSV on oxidative stress induced neurotoxicity. We used hydrogen peroxide (H2O2) exposure for 6 h to model oxidative stress. Therefore, this experimental design allowed us to explore the neuroprotective potential of CSV in H2O2-induced toxicity in new-born rat cerebral cortex cell cultures for the first time. For this aim, MTT and lactate dehydrogenase release assays were carried out to evaluate cytotoxicity. Total antioxidant capacity (TAC) and total oxidative stress (TOS) parameters were used to evaluate oxidative changes. In addition to determining of 8-hydroxy-2-deoxyguanosine (8-OH-dG) levels, the single cell gel electrophoresis (or Comet assay) was also performed for measuring the resistance of neuronal DNA to H2O2-induced challenge. Our results showed that survival and TAC levels of the cells decreased, while TOS, 8-OH-dG levels and the mean values of the total scores of cells showing DNA damage (Comet assay) increased in the H2O2 alone treated cultures. But pre-treatment of CSV suppressed the cytotoxicity, genotoxicity and oxidative stress which were increased by H2O2. On the basis of these observations, it is suggested that CSV as a natural product with an antioxidant capacity in mitigating oxidative injuries in the field of neurodegenerative disorders. 相似文献
124.
Piera Fogliati Manuela Straneo Cosimo Brogi Pier Lorenzo Fantozzi Robert Mahimbo Salim Hamis Mwendo Msengi Gaetano Azzimonti Giovanni Putoto 《PloS one》2015,10(9)
Introduction
Maternal and perinatal mortality remain a challenge in resource-limited countries, particularly among the rural poor. To save lives at birth health facility delivery is recommended. However, increasing coverage of institutional deliveries may not translate into mortality reduction if shortage of qualified staff and lack of enabling working conditions affect quality of services. In Tanzania childbirth care is available in all facilities; yet maternal and newborn mortality are high. The study aimed to assess in a high facility density rural context whether a health system organization with fewer delivery sites is feasible in terms of population access.Methods
Data on health facilities’ location, staffing and delivery caseload were examined in Ludewa and Iringa Districts, Southern Tanzania. Geospatial raster and network analysis were performed to estimate access to obstetric services in walking time. The present geographical accessibility was compared to a theoretical scenario with a 40% reduction of delivery sites.Results
About half of first-line health facilities had insufficient staff to offer full-time obstetric services (45.7% in Iringa and 78.8% in Ludewa District). Yearly delivery caseload at first-line health facilities was low, with less than 100 deliveries in 48/70 and 43/52 facilities in Iringa and Ludewa District respectively. Wide geographical overlaps of facility catchment areas were observed. In Iringa 54% of the population was within 1-hour walking distance from the nearest facility and 87.8% within 2 hours, in Ludewa, the percentages were 39.9% and 82.3%. With a 40% reduction of delivery sites, approximately 80% of population will still be within 2 hours’ walking time.Conclusions
Our findings from spatial modelling in a high facility density context indicate that reducing delivery sites by 40% will decrease population access within 2 hours by 7%. Focused efforts on fewer delivery sites might assist strengthening delivery services in resource-limited settings. 相似文献125.
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127.
Miccichè F Da Riva L Fabbi M Pilotti S Mondellini P Ferrini S Canevari S Pierotti MA Bongarzone I 《PloS one》2011,6(2):e17141
Activated leukocyte cell adhesion molecule (ALCAM, CD166) is expressed in various tissues, cancers, and cancer-initiating cells. Alterations in expression of ALCAM have been reported in several human tumors, and cell adhesion functions have been proposed to explain its association with cancer. Here we documented high levels of ALCAM expression in human thyroid tumors and cell lines. Through proteomic characterization of ALCAM expression in the human papillary thyroid carcinoma cell line TPC-1, we identified the presence of a full-length membrane-associated isoform in cell lysate and of soluble ALCAM isoforms in conditioned medium. This finding is consistent with proteolytically shed ALCAM ectodomains. Nonspecific agents, such as phorbol myristate acetate (PMA) or ionomycin, provoked increased ectodomain shedding. Epidermal growth factor receptor stimulation also enhanced ALCAM secretion through an ADAM17/TACE-dependent pathway. ADAM17/TACE was expressed in the TPC-1 cell line, and ADAM17/TACE silencing by specific small interfering RNAs reduced ALCAM shedding. In addition, the CGS27023A inhibitor of ADAM17/TACE function reduced ALCAM release in a dose-dependent manner and inhibited cell migration in a wound-healing assay. We also provide evidence for the existence of novel O-glycosylated forms and of a novel 60-kDa soluble form of ALCAM, which is particularly abundant following cell stimulation by PMA. ALCAM expression in papillary and medullary thyroid cancer specimens and in the surrounding non-tumoral component was studied by western blot and immunohistochemistry, with results demonstrating that tumor cells overexpress ALCAM. These findings strongly suggest the possibility that ALCAM may have an important role in thyroid tumor biology. 相似文献
128.
Iron is a fundamental element for humans as it represents an essential component of many proteins and enzymes. However, this element can also be toxic when present in excess because of its ability to generate reactive oxygen species. This dual nature imposes a tight regulation of iron concentration in the body. In humans, systemic iron homeostasis is mainly regulated at the level of intestinal absorption and, until now, no regulated pathways for the excretion of iron have been found. The regulation and maintenance of systemic iron homeostasis is critical to human health. Excessive iron absorption leads to iron-overload in parenchyma, while low iron absorption leads to plasma iron deficiency, which manifests as hypoferremia (iron deficiency, ID) and ID anaemia (IDA). ID and IDA are still a major health problem in pregnant women. To cure ID and IDA, iron supplements are routinely prescribed. The preferred treatment of ID/IDA, consisting in oral administration of iron as ferrous sulphate, often fails to exert significant effects on hypoferremia and may also cause adverse effects. Lactoferrin (Lf), an iron-binding glycoprotein abundantly found in exocrine secretions of mammals, is emerging as an important regulator of systemic iron homeostasis. Recent data suggest that this natural compound, capable of interacting with the most important components of iron homeostasis, may represent a valuable alternative to iron supplements in the prevention and cure of pregnancy-associated ID and IDA. In this review, recent advances in the molecular circuits involved in the complex cellular and systemic iron homeostasis will be summarised. The role of Lf in curing ID and IDA in pregnancy and in the maintenance of iron homeostasis will also be discussed. Understanding these mechanisms will provide the rationale for the development of novel therapeutic alternatives to ferrous sulphate oral administration in the prevention and cure of ID and IDA. 相似文献
129.
130.
Jamil Aarbiou Elena Copreni Ruvalic M. Buijs‐Offerman Pascal van der Wegen Stefano Castellani Annalucia Carbone Francesca Tilesi Piera Fradiani Pieter S. Hiemstra Guelnihal Yueksekdag Anna Diana Joseph Rosenecker Fiorentina Ascenzioni Massimo Conese Bob J. Scholte 《The journal of gene medicine》2012,14(12):733-745