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971.
Davidescu M Sciaccaluga M Macchioni L Angelini R Lopalco P Rambotti MG Roberti R Corcelli A Castigli E Corazzi L 《Journal of bioenergetics and biomembranes》2012,44(1):51-60
The GL15 glioblastoma cell line undergoes viability loss upon treatment with bromopyruvate. The biochemical mechanisms triggered
by the antiglycolytic agent indicate the activation of an autophagic pathway. Acridine orange stains acidic intracellular
vesicles already 60 min after bromopyruvate treatment, whereas autophagosomes engulfing electron dense material are well evidenced
18 h later. The autophagic process is accompanied by the expression of the early autophagosomal marker Atg5 and by LC3-II
formation, a late biochemical marker associated with autophagosomes. In agreement with the autophagic route activation, the
inhibitory and the activator Akt and ERK signaling pathways are depressed and enhanced, respectively. In spite of the energetic
collapse suffered by bromopyruvate-treated cells, MALDI-TOF mass spectrometry lipid analysis does not evidence a decrease
of the major phospholipids, in accordance with the need of phospholipids for autophagosomal membranes biogenesis. Contrarily,
mitochondrial cardiolipin decreases, accompanied by monolyso-cardiolipin formation and complete cytochrome c degradation,
events that could target mitochondria to autophagy. However, in our experimental conditions cytochrome c degradation seems
to be independent of the autophagic process. 相似文献
972.
Zaccagnino P D'Oria S Romano LL Di Venere A Sardanelli AM Lorusso M 《Journal of bioenergetics and biomembranes》2012,44(2):273-280
2-Arachidonoylglicerol (2-AG) is an endocannabinoid that mimics the pharmacological effects of Δ9 tetrahydrocannabinol, the psychoactive component of the plant Cannabis sativa. It is present in many mammalian tissues, such as brain, liver, spleen, heart and kidney, where it exerts different biological
effects either receptor mediated or independently of receptor activation. This work analyzes the effects of 2-AG on liver
mitochondrial functions. It is shown that 2-AG causes a relevant decrease of calcium induced cyclosporine A sensitive cytochrome
c release from mitochondria, a process representing an early event of the apoptotic program. Cyclosporin sensitive matrix
swelling and ROS production measured under the same conditions are, on the contrary, almost unaffected or even enhanced, respectively,
by 2-AG. Furthemore, 2-AG is found to stimulate resting state succinate oxidase activity and to inhibit oligomycin sensitive
FoF1 ATP synthase activity. All these effects are apparently associated with 2-AG dependent alteration in the fluidity of the
mitochondrial membranes, which was measured as generalized polarization of laurdan fluorescence. 相似文献
973.
974.
Scalzi G Selbmann L Zucconi L Rabbow E Horneck G Albertano P Onofri S 《Origins of life and evolution of the biosphere》2012,42(2-3):253-262
Desiccated Antarctic rocks colonized by cryptoendolithic communities were exposed on the International Space Station (ISS) to space and simulated Mars conditions (LiFE-Lichens and Fungi Experiment). After 1.5?years in space samples were retrieved, rehydrated and spread on different culture media. Colonies of a green alga and a pink-coloured fungus developed on Malt-Agar medium; they were isolated from a sample exposed to simulated Mars conditions beneath a 0.1?%?T Suprasil neutral density filter and from a sample exposed to space vacuum without solar radiation exposure, respectively. None of the other flight samples showed any growth after incubation. The two organisms able to grow were identified at genus level by Small SubUnit (SSU) and Internal Transcribed Spacer (ITS) rDNA sequencing as Stichococcus sp. (green alga) and Acarospora sp. (lichenized fungal genus) respectively. The data in the present study provide experimental information on the possibility of eukaryotic life transfer from one planet to another by means of rocks and of survival in Mars environment. 相似文献
975.
Linde CI Karashima E Raina H Zulian A Wier WG Hamlyn JM Ferrari P Blaustein MP Golovina VA 《American journal of physiology. Heart and circulatory physiology》2012,302(3):H611-H620
The Milan hypertensive strain (MHS) rats are a genetic model of hypertension with adducin gene polymorphisms linked to enhanced renal tubular Na(+) reabsorption. Recently we demonstrated that Ca(2+) signaling is augmented in freshly isolated mesenteric artery myocytes from MHS rats. This is associated with greatly enhanced expression of Na(+)/Ca(2+) exchanger-1 (NCX1), C-type transient receptor potential (TRPC6) protein, and sarco(endo)plasmic reticulum Ca(2+)-ATPase (SERCA2) compared with arteries from Milan normotensive strain (MNS) rats. Here, we test the hypothesis that the enhanced Ca(2+) signaling in MHS arterial smooth muscle is directly reflected in augmented vasoconstriction [myogenic and phenylephrine (PE)-evoked responses] in isolated mesenteric small arteries. Systolic blood pressure was higher in MHS (145 ± 1 mmHg) than in MNS (112 ± 1 mmHg; P < 0.001; n = 16 each) rats. Pressurized mesenteric resistance arteries from MHS rats had significantly augmented myogenic tone and reactivity and enhanced constriction to low-dose (1-100 nM) PE. Isolated MHS arterial myocytes exhibited approximately twofold increased peak Ca(2+) signals in response to 5 μM PE or ATP in the absence and presence of extracellular Ca(2+). These augmented responses are consistent with increased vasoconstrictor-evoked sarcoplasmic reticulum (SR) Ca(2+) release and increased Ca(2+) entry, respectively. The increased SR Ca(2+) release correlates with a doubling of inositol 1,4,5-trisphosphate receptor type 1 and tripling of SERCA2 expression. Pressurized MHS arteries also exhibited a ~70% increase in 100 nM ouabain-induced vasoconstriction compared with MNS arteries. These functional alterations reveal that, in a genetic model of hypertension linked to renal dysfunction, multiple mechanisms within the arterial myocytes contribute to enhanced Ca(2+) signaling and myogenic and vasoconstrictor-induced arterial constriction. MHS rats have elevated plasma levels of endogenous ouabain, which may initiate the protein upregulation and enhanced Ca(2+) signaling. These molecular and functional changes provide a mechanism for the increased peripheral vascular resistance (whole body autoregulation) that underlies the sustained hypertension. 相似文献
976.
Petronella P Scorzelli M Luise R Iannaci G Sapere P Ferretti M Costanzo RM Freda F Canonico S Rossiello R 《World journal of surgical oncology》2012,10(1):73
ABSTRACT: The finding of thyroid nodules is a very common occurrence in routine clinical practice. Approximately 5% to 7% of the entire population have thyroid nodules. Vascular lesions are one of the most controversial issues in thyroid pathology. These include benign lesions such as hemangiomas and, rarely, malignant tumors such as angiosarcomas or undifferentiated angiosarcomatoid carcinomas. In particular, angiosarcoma of the thyroid gland is a rare, highly aggressive malignant vascular tumor and in Italy the greatest geographical incidence of this lesion is witnessed near the Alps. Here, a case of thyroid angiosarcoma in a 71-year-old man with a history of goiter for about 20 years is described. The unusual localization of this lesion, the difficulties in reaching a definitive diagnosis for this particular histological type of primary tumor and a history of long-standing multinodular goiter in thyroid of an older man from outside the Alpine region prompted us to report this case of thyroid angiosarcoma mainly to discuss surgical, histopathological and immunohistochemical features. 相似文献
977.
Andrea Riccardo Filippi Filippo Alongi Patrizia Ciammella Berardino De Bari Pierfrancesco Franco Lorenzo Livi 《Reports of Practical Oncology and Radiotherapy》2012,17(5):259-261
AimTo briefly review history, structure, past events and future projects of AIRO (Associazione Italiana Radioterapia Oncologica) young group (AIRO Giovani), focusing on its specific commitment to multidisciplnary networking among junior clinical oncologists at a national and international level.BackgroundAIRO Giovani is a part of AIRO composed by members under 40 years old. Its main activities are scientific and educational meetings dedicated to young Italian radiation oncologists and collaborative research projects.Materials and MethodsAIRO Giovani structure, events organized and supported by AIRO giovani as well as scientific activities are here reported from its creation in 2007 up to current days.ResultsAIRO Giovani group was able to create a consolidated network between Italian junior radiation oncologists, while opening the possibility to collaborate with junior groups of other national scientific societies in the field of oncology and with ESTRO young members. Scientific projects carried out by the group have been successful and will be further implemented in next years.ConclusionsAIRO Giovani is still in its infancy, but its early positive experience supports the creation and development of young groups within national radiation oncology societies. 相似文献
978.
Anna?Maria?BerghellaEmail author Ida?Contasta Tiziana?Del Beato Patrizia?Pellegrini 《Immunity & ageing : I & A》2012,9(1):24
The control of human health and diseases in the elderly population is becoming a challenge, since mean age and life expectation are progressively increasing as well as chronic degenerative diseases. These disorders are of complex diagnosis and they are difficult to be treated, but it is hoped that the predictive medicine will lead to more specific and effective treatment by using specific markers to identify persons with high risk of developing disease, before the clinical manifestation. Peripheral blood targets and biomarkers are currently the most practical, non-invasive means of disease diagnosing, predicting prognosis and therapeutic response. Human longevity is directly correlated with the optimal functioning of the immune system. Recent findings indicate that the sexual dimorphism of T helper (Th) cytokine pathways and the regulation of Th cell network homeostasis are normally present in the immune response and undergoes to adverse changes with ageing. Furthermore, immune senescence affects both men and women, but it does not affect them equally. Therefore, we hypothesize that the comprehension of the interferences between these gender specific pathways, the ageing immunological mechanism in pathological or healthy state and the current therapies, could lead to specifically tailored treatment and eventually improve the therapeutic success rates. Reaching this aim requires the identification of ageing gender-specific biomarkers that could easily reveal the above mentioned correlations. 相似文献
979.
Ettore Ambrosini Marco Ciavarro Gina Pelle Mauro Gianni Perrucci Gaspare Galati Patrizia Fattori Claudio Galletti Giorgia Committeri 《PloS one》2012,7(12)
Background
Several psychophysical experiments found evidence for the involvement of gaze-centered and/or body-centered coordinates in arm-movement planning and execution. Here we aimed at investigating the frames of reference involved in the visuomotor transformations for reaching towards visual targets in space by taking target eccentricity and performing hand into account.Methodology/Principal Findings
We examined several performance measures while subjects reached, in complete darkness, memorized targets situated at different locations relative to the gaze and/or to the body, thus distinguishing between an eye-centered and a body-centered frame of reference involved in the computation of the movement vector. The errors seem to be mainly affected by the visual hemifield of the target, independently from its location relative to the body, with an overestimation error in the horizontal reaching dimension (retinal exaggeration effect). The use of several target locations within the perifoveal visual field allowed us to reveal a novel finding, that is, a positive linear correlation between horizontal overestimation errors and target retinal eccentricity. In addition, we found an independent influence of the performing hand on the visuomotor transformation process, with each hand misreaching towards the ipsilateral side.Conclusions
While supporting the existence of an internal mechanism of target-effector integration in multiple frames of reference, the present data, especially the linear overshoot at small target eccentricities, clearly indicate the primary role of gaze-centered coding of target location in the visuomotor transformation for reaching. 相似文献980.
Micaela Pivato Giorgia De Franceschi Laura Tosatto Erica Frare Dhruv Kumar Daniel Aioanei Marco Brucale Isabella Tessari Marco Bisaglia Bruno Samori Patrizia Polverino de Laureto Luigi Bubacco 《PloS one》2012,7(12)
The aggregation of α-synuclein into amyloid fibrils constitutes a key step in the onset of Parkinson''s disease. Amyloid fibrils of α-synuclein are the major component of Lewy bodies, histological hallmarks of the disease. Little is known about the mechanism of aggregation of α-synuclein. During this process, α-synuclein forms transient intermediates that are considered to be toxic species. The dimerization of α-synuclein could represent a rate-limiting step in the aggregation of the protein. Here, we analyzed four covalent dimers of α-synuclein, obtained by covalent link of the N-terms, C-terms, tandem cloning of two sequences and tandem juxtaposition in one protein of the 1–104 and 29–140 sequences. Their biophysical properties in solution were determined by CD, FT-IR and NMR spectroscopies. SDS-induced folding was also studied. The fibrils formation was analyzed by ThT and polarization fluorescence assays. Their morphology was investigated by TEM and AFM-based quantitative morphometric analysis. All dimers were found to be devoid of ordered secondary structure under physiological conditions and undergo α-helical transition upon interaction with SDS. All protein species are able to form amyloid-like fibrils. The reciprocal orientation of the α-synuclein monomers in the dimeric constructs affects the kinetics of the aggregation process and a scale of relative amyloidogenic propensity was determined. Structural investigations by FT IR spectroscopy, and proteolytic mapping of the fibril core did not evidence remarkable difference among the species, whereas morphological analyses showed that fibrils formed by dimers display a lower and diversified level of organization in comparison with α-synuclein fibrils. This study demonstrates that although α-synuclein dimerization does not imply the acquisition of a preferred conformation by the participating monomers, it can strongly affect the aggregation properties of the molecules. The results presented highlight a substantial role of the relative orientation of the individual monomer in the definition of the fibril higher structural levels. 相似文献