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71.
Laura Roesler Nery Natalia Silva Eltz Cristiana Hackman Raphaela Fonseca Stefani Altenhofen Heydi Noriega Guerra Vanessa Morais Freitas Carla Denise Bonan Monica Ryff Moreira Roca Vianna 《PloS one》2014,9(9)
Alzheimer’s disease (AD) is a devastating neurodegenerative disorder with no effective treatment and commonly diagnosed only on late stages. Amyloid-β (Aβ) accumulation and exacerbated tau phosphorylation are molecular hallmarks of AD implicated in cognitive deficits and synaptic and neuronal loss. The Aβ and tau connection is beginning to be elucidated and attributed to interaction with different components of common signaling pathways. Recent evidences suggest that non-fibrillary Aβ forms bind to membrane receptors and modulate GSK-3β activity, which in turn phosphorylates the microtubule-associated tau protein leading to axonal disruption and toxic accumulation. Available AD animal models, ranging from rodent to invertebrates, significantly contributed to our current knowledge, but complementary platforms for mechanistic and candidate drug screenings remain critical for the identification of early stage biomarkers and potential disease-modifying therapies. Here we show that Aβ1–42 injection in the hindbrain ventricle of 24 hpf zebrafish embryos results in specific cognitive deficits and increased tau phosphorylation in GSK-3β target residues at 5dpf larvae. These effects are reversed by lithium incubation and not accompanied by apoptotic markers. We believe this may represent a straightforward platform useful to identification of cellular and molecular mechanisms of early stage AD-like symptoms and the effects of neuroactive molecules in pharmacological screenings. 相似文献
72.
Sevinci Pop Ana‐Maria Enciu Laura G. Necula Cristiana Tanase 《Journal of cellular and molecular medicine》2018,22(10):4597-4610
Glioma biology is a major focus in tumour research, primarily due to the aggressiveness and high mortality rate of its most aggressive form, glioblastoma. Progress in understanding the molecular mechanisms behind poor prognosis of glioblastoma, regardless of treatment approaches, has changed the classification of brain tumours after nearly 100 years of relying on anatomopathological criteria. Expanding knowledge in genetic, epigenetic and translational medicine is also beginning to contribute to further elucidating molecular dysregulation in glioma. Long non‐coding RNAs (lncRNAs) and their main representatives, large intergenic non‐coding RNAs (lincRNAs), have recently been under scrutiny in glioma research, revealing novel mechanisms of pathogenesis and reinforcing others. Among those confirmed was the reactivation of events significant for foetal brain development and neuronal commitment. Novel mechanisms of tumour suppression and activation of stem‐like behaviour in tumour cells have also been examined. Interestingly, these processes involve lncRNAs that are present both during normal brain development and in brain malignancies and their reactivation might be explained by epigenetic mechanisms, which we discuss in detail in the present review. In addition, the review discusses the lncRNAs‐induced changes, as well as epigenetic changes that are consequential for tumour formation, affecting, in turn, the expression of various types of lncRNAs. 相似文献
73.
Ricardo M. Chaloub Cristiana C. P. de Magalhes Cesar P. Dos Santos 《Journal of phycology》2005,41(6):1162-1168
Zinc toxicity on photosynthetic activity in cells of Synechocystis aquatilis f. aquatilis Sauvageau was investigated by monitoring Hill activity and fluorescence. The oxygen‐evolving activity decreased to about 80% of the initial value after exposure to 0.1 mM ZnSO4 for 1 h. The PSII activity was inhibited by 40% in the presence of zinc concentrations ranging from 0.5 to 5.0 mM, suggesting that the metal effect is limited by zinc uptake. The fluorescence capacity (Fmax–F/Fmax) decreased from 0.57 to 0.35 and 0.20 in Zn‐treated cells for 15 and 60 min, respectively, thus providing evidence for rapid inactivation of electron transport at PSII. Zinc treatment promoted a rapid increase in PSII fluorescence that was counteracted by addition of 1,4‐benzoquinone, indicating that electron transfer at the reducing side of the PSII reaction center is arrested by zinc. Furthermore, a decline in the fluorescence yield could be observed after 1 h of zinc treatment as well as when Zn‐treated cells were excited in presence of 3‐(3′,4′‐dichlorophenyl)‐1,1‐dimethylurea. Under these conditions, zinc did not affect energy transfer from phycobilisomes to PSII, and the gradual quenching of PSII fluorescence may be due to a decrease in electron flow on the donor side of PSII. However, the 20% increase in the minimal fluorescence intensity (Fo) in parallel to the absence of changes in the maximal fluorescence intensity (Fmax), observed in the first hour of zinc treatment, could also suggest a metal‐induced decline in the energy transfer from PSII‐chl a antenna to the PSII reaction center. 相似文献
74.
Differential toxicity of TAR DNA‐binding protein 43 isoforms depends on their submitochondrial localization in neuronal cells
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Illari Salvatori Alberto Ferri Silvia Scaricamazza Ilaria Giovannelli Alessia Serrano Simona Rossi Nadia D'Ambrosi Mauro Cozzolino Andrea Di Giulio Sandra Moreno Cristiana Valle Maria Teresa Carrì 《Journal of neurochemistry》2018,146(5):585-597
75.
Serum From Advanced Heart Failure Patients Promotes Angiogenic Sprouting and Affects the Notch Pathway in Human Endothelial Cells
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Micaela Pannella Cristiana Caliceti Francesca Fortini Giorgio Aquila Francesco Vieceli Dalla Sega Antonio Pannuti Cinzia Fortini Marco Bruno Morelli Alessandro Fucili Gloria Francolini Rebecca Voltan Paola Secchiero Giovanni Dinelli Emanuela Leoncini Manuela Ferracin Silvana Hrelia Lucio Miele Paola Rizzo 《Journal of cellular physiology》2016,231(12):2700-2710
76.
De Rosa MC Carelli Alinovi C Schininà ME Clementi ME Amato A Cappabianca MP Pezzotti M Giardina B 《Biochimica et biophysica acta》2007,1774(10):1299-1306
This study examines the functional and structural effects of amino acid substitution at alpha(1)beta(2) interface of Hb Santa Clara (beta 97His-->Asn). We have characterized the variation by a combination of electrospray ionisation mass spectrometry and DNA sequence analysis followed by oxygen-binding experiments. Functional studies outlined an increased oxygen affinity, reduced effect of organic phosphates and a reduced Bohr effect with respect to HbA. In view of the primary role of this interface in the cooperative quaternary transition from the T to R conformational state, a theoretical three-dimensional model of Hb Santa Clara was generated. Structural investigations suggest that replacement of Asn for His beta 97 results in a significant stabilization of the high affinity R-state of the haemoglobin molecule with respect to the low affinity T-state. The role of beta FG4 position has been further examined by computational models of known beta FG4 variants, namely Hb Malm? (beta 97His-->Gln), Hb Wood (beta 97His-->Leu), Hb Nagoya (beta 97His-->Pro) and Hb Moriguchi (beta 97His-->Tyr). These findings demonstrate that, among the various residues at the alpha(1)beta(2) (and alpha(2)beta(1)) intersubunit interface, His beta FG4 contributes significantly to the quaternary constraints that are responsible for the low oxygen affinity of human deoxyhaemoglobin. 相似文献
77.
Within the red blood cell the hemoglobin molecule is subjected to modulation mechanisms, namely homo- and heterotropic interactions, which optimize its functional behavior to the specific physiological requirements. At the cellular level, these modulation mechanisms are utilized to perform a number of other functions that are not minor with respect to the basic function of oxygen transport. Here we report some key examples concerning: (i) the interaction of hemoglobin with band 3 and its influence on glucose metabolism; (ii) the role of the ligand-linked quaternary transition of hemoglobin in the control of "NO bioactivity" and of gas diffusion; (iii) the interaction of plasma membrane with the various oxidative derivatives of the hemoglobin molecule. 相似文献
78.
Giovanni Caudullo Renzo De Battisti Cristiana Colpi Claudio Vazzola Flavio Da Ronch 《Journal for Nature Conservation》2003,10(4):233-241
The Cansiglio Forest, situated in the Veneto Prealps, is of particular naturalistic and landscape interest, going back to the times of the Most Serene Republic of Venice. Its long silvicultural tradition, which is now even more “near to nature”, remains unaltered. Over the last century there has been a considerable increase in the number of ungulates. This is partly due to prohibition of hunting since the beginning of the 20th century throughout the territory. It has therefore become necessary to survey forest regeneration, to ascertain whether deer pressure hampers silvicultural goals and also to investigate which factors are most involved. A review of management plans over the last 30 years identified areas in which regeneration is present, where transects were subsequently sampled. Inside every transect, all saplings (over 50 cm) were measured for diameter and height and monitored for degree and type of damage (browsing, debarking, fraying). Using the CART statistical method, the following key factors were singled out: species, proving that fir is the most frequently selected sapling; silvicultural system, clarifying that the regeneration of uneven-aged stands is more subject to damage; aspect, locating more damage in the southern and eastern areas, probably because they are more often frequented by deer. High densities of deer endanger fir survival, reduce biodiversity, and affect forest economy, limiting silvicultural choices, so that culling ungulate populations seems to be necessary. 相似文献
79.
80.
Joana Martins Martin L. Saker Cristiana Moreira Martin Welker Jutta Fastner Vitor M. Vasconcelos 《Applied microbiology and biotechnology》2009,82(5):951-961
Strains of the cyanobacterium Microcystis aeruginosa were isolated into pure culture from a variety of lakes, rivers, and reservoirs in Portugal. Samples were tested with matrix-assisted
laser desorption/ionization–time-of-flight mass spectrometry (MALDI-TOF MS) to investigate the presence of various peptide
groups including aeruginosins, microginins, anabaenopeptins, cyanopeptilins, microcystins, and microviridins and other peptide-like
compounds. Binary data, based on the presence and absence of different peptide groups, were analyzed by phylogenetic inference.
DNA was also extracted from the samples and tested using a range of primers. Those strains that gave positive results for
a Microcystis-specific primer pair were further analyzed for the presence of genes linked to the biosynthesis of microginin and microcystin.
The results showed that a wide range of microcystin forms were produced by the strains among which MC-LR, -FR, -RR, -WR, and
-YR were the most common. The peptide profiles obtained from the MALDI analysis were assessed using cluster analysis which
resulted in the formation of distinct groups or chemotypes. 相似文献