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181.
Messere A Fabbri E Borgatti M Gambari R Di Blasio B Pedone C Romanelli A 《Journal of inorganic biochemistry》2007,101(2):254-260
Oxidative addition reactions between [M(PPh(3))(4)] (M=Pt and Pd) and N1-methylthymine (t)/3',5'-di-O-acetylthymidine (T) were carried out to give [M(II)(PPh(3))(2)Cl t (or T)] complexes, in which the metal is coordinated to the N3 of the base. All complexes were characterized by spectroscopic analyses (IR, NMR) and Fast Atom Bombardment mass spectrometry (FAB-MS); X-ray data for the thymine complexes and elemental analysis for the thymidine complexes are reported. The antiproliferative activity of the complexes was tested on human chronic myelogenous leukaemia K562 cells. Arrested polymerase-chain reaction analysis was carried on to correlate antiproliferative activity and inhibition of DNA replication. All Pd and Pt complexes exhibit antiproliferative activity, Pd complexes resulting always more active than Pt complexes. Arrested PCR data are strongly in agreement with the effects on cell growth, suggesting that inhibition of the DNA replication by the synthesized compounds is the major basis for their in vitro antiproliferative activity. 相似文献
182.
Rossana Martini Simonetta Cirilli Céline Saurer Benedetto Abate Gaetano Ferruzza Giovanna Lo Cicero 《Facies》2007,53(3):389-400
The aims of this study are to reconstruct the geological setting of the Punta Bassano series (Marettimo Island, Egadi Archipelago,
western Sicily) and its palaeogeographic evolution. The reference section for the Upper Triassic of Marettimo shows an alternation
of marl and limestone beds together with brecciated levels. The limestones are both homogeneous mudstones with evaporite pseudomorphs
and laminated with fenestrae. Foraminiferal, palynomorph, and ostracod associations constrain the Punta Bassano sequence to
the Carnian-Rhaetian interval. The Punta Bassano succession represents a shallow inner ramp, ranging from open-marine environment
with good water circulation to lagoonal and peritidal protected environments. Freshwater input from rivers or groundwater
on the carbonate ramp is indicated by the ostracod microfauna. The comparison of facies and microfauna with those from other
sequences of the Mediterranean Upper Triassic (Pyrenees, Corsica, Sardinia, and Tunisia) allows us to confine the Punta Bassano
sedimentation to the northern margin of the Tethys, between the Corsican and the Pyrenean depositional setting. These new
results indicate that Marettimo Island, which is considered a single structural element being formed by four tectonic units,
is a piece of the southern margin of the European Plate, displaced over a longer distance to become part of the other Egadi
Islands, when the Corso-Sarde block made its rotation and successive collision with the North African Margin. 相似文献
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184.
Alexandre Benedetto Timothe Bambade Catherine Au Jennifer M.A. Tullet Jennifer Monkhouse Hairuo Dang Kalina Cetnar Brian Chan Filipe Cabreiro David Gems 《Aging cell》2019,18(5)
Caenorhabditis elegans is an excellent model for high‐throughput experimental approaches but lacks an automated means to pinpoint time of death during survival assays over a short time frame, that is, easy to implement, highly scalable, robust, and versatile. Here, we describe an automated, label‐free, high‐throughput method using death‐associated fluorescence to monitor nematode population survival (dubbed LFASS for label‐free automated survival scoring), which we apply to severe stress and infection resistance assays. We demonstrate its use to define correlations between age, longevity, and severe stress resistance, and its applicability to parasitic nematodes. The use of LFASS to assess the effects of aging on susceptibility to severe stress revealed an unexpected increase in stress resistance with advancing age, which was largely autophagy‐dependent. Correlation analysis further revealed that while severe thermal stress resistance positively correlates with lifespan, severe oxidative stress resistance does not. This supports the view that temperature‐sensitive protein‐handling processes more than redox homeostasis underpin aging in C. elegans. That the ages of peak resistance to infection, severe oxidative stress, heat shock, and milder stressors differ markedly suggests that stress resistance and health span do not show a simple correspondence in C. elegans. 相似文献
185.
Marc Miravitlles Heinrich Worth Juan José Soler Catalu?a David Price Fernando De Benedetto Nicolas Roche Nina Skavlan Godtfredsen Thys van der Molen Claes-G?ran L?fdahl Laura Padullés Anna Ribera 《Respiratory research》2014,15(1)
Background
Few studies have investigated the 24-hour symptom profile in patients with COPD or how symptoms during the 24-hour day are inter-related. This observational study assessed the prevalence, severity and relationship between night-time, early morning and daytime COPD symptoms and explored the relationship between 24-hour symptoms and other patient-reported outcomes.Methods
The study enrolled patients with stable COPD in clinical practice. Baseline night-time, early morning and daytime symptoms (symptom questionnaire), severity of airflow obstruction (FEV1), dyspnoea (modified Medical Research Council Dyspnoea Scale), health status (COPD Assessment Test), anxiety and depression levels (Hospital Anxiety and Depression Scale), sleep quality (COPD and Asthma Sleep Impact Scale) and physical activity level (sedentary, moderately active or active) were recorded.Results
The full analysis set included 727 patients: 65.8% male, mean ± standard deviation age 67.2 ± 8.8 years, % predicted FEV1 52.8 ± 20.5%.In each part of the 24-hour day, >60% of patients reported experiencing ≥1 symptom in the week before baseline. Symptoms were more common in the early morning and daytime versus night-time (81.4%, 82.7% and 63.0%, respectively). Symptom severity was comparable for each period assessed. Overall, in the week before baseline, 56.7% of patients had symptoms throughout the whole 24-hour day (3 parts of the day); 79.9% had symptoms in ≥2 parts of the 24-hour day. Symptoms during each part of the day were inter-related, irrespective of disease severity (all p < 0.001).Early morning and daytime symptoms were associated with the severity of airflow obstruction (p < 0.05 for both). Night-time, early morning and daytime symptoms were all associated with worse dyspnoea, health status and sleep quality, and higher anxiety and depression levels (all p < 0.001 versus patients without symptoms in each corresponding period). In each part of the 24-hour day, there was also an association between symptoms and a patient’s physical activity level (p < 0.05 for each period).Conclusions
More than half of patients experienced COPD symptoms throughout the whole 24-hour day. There was a significant relationship between night-time, early morning and daytime symptoms. In each period, symptoms were associated with worse patient-reported outcomes, suggesting that improving 24-hour symptoms should be an important consideration in the management of COPD.Electronic supplementary material
The online version of this article (doi:10.1186/s12931-014-0122-1) contains supplementary material, which is available to authorized users. 相似文献186.
Paola Cipriani Paola Di Benedetto Piero Ruscitti Antonio Francesco Campese Vasiliki Liakouli Francesco Carubbi Ilenia Pantano Onorina Berardicurt Isabella Screpanti Roberto Giacomelli 《Arthritis research & therapy》2014,16(5)
Introduction
To assess if an impaired cross-talk between endothelial cells (ECs) and perivascular/multipotent mesenchymal stem cells (MSCs) might induce a perturbation of vascular repair and leading to a phenotypic switch of MSC toward myofibroblast in Systemic Sclerosis (SSc).Methods
We investigated different angiogenic and profibrotic molecules in a tridimentional matrigel assay, performing co-cultures with endothelial cells (ECs) and bone marrow derived MSCs from patients and healthy controls (HC). After 48 hours of co-culture, cells were sorted and analyzed for mRNA and protein expression.Results
ECs-SSc showed a decreased tube formation ability which is not improved by co-cultures with different MSCs. After sorting, we showed: i. an increased production of vascular endothelial growth factor A (VEGF-A) in SSc-MSCs when co-cultured with SSc-ECs; ii. an increased level of transforming growth factor beta (TGF-β) and platelet growth factor BB (PDGF-BB) in SSc-ECs when co-cultured with both HC- and SSc-MSCs; iii. an increase of TGF-β, PDGF-R, alpha smooth muscle actin (α-SMA) and collagen 1 (Col1) in both HC- and SSc-MSCs when co-cultured with SSc-ECs.Conclusion
We showed that during SSc, the ECs-MSCs crosstalk resulted in an altered expression of different molecules involved in the angiogenic processes, and mainly SSc-ECs seem to modulate the phenotypic switch of perivascular MSCs toward a myofibroblast population, thus supporting the fibrotic process. 相似文献187.
Roat E De Biasi S Bertoncelli L Rompianesi G Nasi M Gibellini L Pinti M Del Giovane C Zanella A Di Benedetto F Gerunda GE Cossarizza A 《Cytometry. Part A》2012,81(4):303-311
Several immunosuppressive drugs with different mechanisms of action are available to inhibit organ rejection after transplant. We analyzed different phenotypic and functional immunological parameters in liver-transplanted patients who received cyclosporin A (CsA) or Everolimus (Evr). In peripheral blood mononuclear cells (PBMC) from 29 subjects receiving a liver transplant and treated with two different immunosuppressive regimens, we analyzed T cell activation and differentiation, regulatory T cells (Tregs) and Tregs expressing homing receptors such as the chemokine receptor CXCR3. T cell polyfunctionality was studied by stimulating cells with the superantigen staphylococcal enterotoxin B (SEB), and measuring the simultaneous production of interleukin (IL)-2 and interferon (IFN)-γ, along with the expression of a marker of cytotoxicity such as CD107a. The analyses were performed by polychromatic flow cytometry before transplantation, and at different time points, up to 220 days after transplant. Patients taking Evr had a higher percentage of total CD4? and na?ve CD4? T cells than those treated with CsA; the percentage of CD8? T cells was lower, but the frequency of na?ve CD8? T cells higher. Patients taking Evr showed a significantly higher percentage of Tregs, and Tregs expressing CXCR3. After stimulation with SEB, CD8? T cells from Evr-treated patients displayed a lower total response, and less IFN-γ producing cells. The effects on the immune system, such as the preservation of the na?ve T cell pool and the expansion of Tregs (that are extremely useful in inhibiting organ rejection), along with the higher tolerability of Evr, suggest that this drug can be safely used after liver transplantation, and likely offers immunological advantages. 相似文献
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