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41.
42.
Gabriella Gruden Patrizia Carucci Federica Barutta Davina Burt Arianna Ferro Emanuela Rolle Silvia Pinach Maria Lorena Abate Donata Campra Marilena Durazzo 《Cell stress & chaperones》2021,26(1):151
Heat shock protein 27 (HSP27), an intracellular molecular chaperone, is involved in the pathogenesis of cancer by promoting both tumor cell proliferation and resistance to therapy. HSP27 is also present in the circulation and circulating HSP27 (sHSP27) can elicit an autoimmune response with production of antibodies. Levels of sHSP27 are enhanced in patients with hepatocellular carcinoma (HCC); it is, however, unknown whether changes in HSP27 antibody levels occur in patients with HCC and can be exploited as a circulating biomarker of HCC. Our aim was to assess the potential association between newly diagnosed HCC and serum anti-HSP27 antibody levels. In this cross-sectional study, anti-HSP27 antibody levels were measured in serum samples from 71 HCC patients, 80 subjects with chronic liver disease, and 38 control subjects by immunoenzymatic assay. Anti-HSP27 antibody levels did not differ significantly among groups. However, in patients with chronic active hepatitis/cirrhosis, anti-HSP27 levels were significantly higher in subjects with a positive history of alcoholism (p = 0.03). Our data do not support the hypothesis that anti-HSP27 antibody levels may help identify patients with HCC among subjects with chronic liver disease. However, our finding that alcohol-related liver disease is associated with higher anti-HSP27 levels is novel and deserves further investigations. 相似文献
43.
Roberta Bonfiglioli Patrizia Mussoni Francesca Graziosi Monica Calabrese Andrea Farioli Francesco Marinelli Francesco S. Violante 《Journal of electromyography and kinesiology》2013,23(1):252-259
To test whether the influence of manual activity should be considered when interpreting the results of nerve conduction study (NCS) of the upper limbs performed during work shifts, we evaluated the short-term effect of 90-min repetitive manual work on NCS parameters. Twenty-eight healthy volunteers underwent NCS of the dominant limb at the end of an interview (T0), after a 30-min rest in sitting position (T1) and after performing a standardized 90-min manual task (T2). The task was designed to simulate typical assembly and packing activities. No significant differences were observed for skin temperature (Ts) and NCS parameters between T0 and T1. Significantly (p < 0.001) higher Ts mean values were found at T2 as compared to the previous tests for both females and males. The regression analysis showed an association between temperature variation and nerve conduction velocity values for the median and ulnar nerve at T2 as compared to T1. In females, a reduction of the mean sensory nerve action potential (SNAP) amplitude at T2 was recorded, whereas an opposite trend was observed among males. Manual work is able to influence hand Ts and to modify NCS parameters. SNAP amplitudes changes suggest gender differences in peripheral nerve characteristics that deserve further investigation. 相似文献
44.
45.
Lucia Ciccoli Viviana Rossi Silvia Leoncini Cinzia Signorini Patrizia Paffetti Rodolfo Bracci 《Free radical research》2013,47(1):51-58
Iron is released in a desferrioxamine (DFO)-chelatable form (DCI) when erythrocytes are challenged by an oxidative stress. In g -thalassemic erythrocytes, both DCI content and release (after aerobic incubation for 24 h) are increased and correlated with the fetal hemoglobin (HbF) levels. Since erythrocytes from newborns have an extremely high content of HbF and are exposed to conditions of oxidative stress, the release of iron in these erythrocytes was investigated. The erythrocyte DCI content was increased in preterm but not in term newborns as compared to adults, while the release was increased in both preterm and term erythrocytes. The level of plasma non protein-bound iron (NPBI), which was not detectable in adults, was much higher in preterm than in term newborns. When term plus preterm newborns were divided in two groups, normoxic and hypoxic, according to cord blood pH, it was found that both iron release and NBPI were markedly higher in the hypoxic newborns compared to normoxic ones. Similar results were also obtained when the preterm and term infants were considered separately on the basis of cord blood pH. Therefore, iron release and NPBI are higher when conditions of hypoxia occur. In fact, when the values for iron release and NPBI were separately plotted against cord blood pH values, significant negative correlations were seen in both cases. NPBI was correlated with iron release seen in all the newborns and a significant part of the released iron could be recovered into the incubation medium at the end of the incubation. 相似文献
46.
Valentina Sanghez Maria Teresa Russo Maria Antonietta Ajmone‐Cat Emanuele Cacci Alberto Martire Patrizia Popoli Germana Falcone Flavia Michelini Marco Crescenzi Paolo Degan Luisa Minghetti Margherita Bignami Gemma Calamandrei 《Aging cell》2013,12(4):695-705
The contribution that oxidative damage to DNA and/or RNA makes to the aging process remains undefined. In this study, we used the hMTH1‐Tg mouse model to investigate how oxidative damage to nucleic acids affects aging. hMTH1‐Tg mice express high levels of the hMTH1 hydrolase that degrades 8‐oxodGTP and 8‐oxoGTP and excludes 8‐oxoguanine from both DNA and RNA. Compared to wild‐type animals, hMTH1‐overexpressing mice have significantly lower steady‐state levels of 8‐oxoguanine in both nuclear and mitochondrial DNA of several organs, including the brain. hMTH1 overexpression prevents the age‐dependent accumulation of DNA 8‐oxoguanine that occurs in wild‐type mice. These lower levels of oxidized guanines are associated with increased longevity and hMTH1‐Tg animals live significantly longer than their wild‐type littermates. Neither lipid oxidation nor overall antioxidant status is significantly affected by hMTH1 overexpression. At the cellular level, neurospheres derived from adult hMTH1‐Tg neural progenitor cells display increased proliferative capacity and primary fibroblasts from hMTH1‐Tg embryos do not undergo overt senescence in vitro. The significantly lower levels of oxidized DNA/RNA in transgenic animals are associated with behavioral changes. These mice show reduced anxiety and enhanced investigation of environmental and social cues. Longevity conferred by overexpression of a single nucleotide hydrolase in hMTH1‐Tg animals is an example of lifespan extension associated with healthy aging. It provides a link between aging and oxidative damage to nucleic acids. 相似文献
47.
Daniel C. Capaldi Alessandra Eleuteri Qin Chen Raymond F. Schinazi 《Nucleosides, nucleotides & nucleic acids》2013,32(4):403-416
Abstract The synthesis of pyrimidine nucleosides, cis-N-1-[(2-hydroxymethyl)-1,3-dioxan-5-yl]uracil (4) cis-N-1-[(2-hydroxymethyl)-1,3-dioxan-5-yl]thymine (5) and cis-N-1-[(2-hydroxymethyl)-1,3-dioxan-5-yl]cytosine (6) and their corresponding trans isomers is described. Compound 4 showed modest, selective activity against human immunodeficiency virus in acutely infected primary human lymphocytes. 相似文献
48.
Alessandra Eleuteri Daniel C. Capaldi Douglas L. Cole Vasulinga T. Ravikumar 《Nucleosides, nucleotides & nucleic acids》2013,32(8):1879-1882
Abstract An efficient, safe and cost effective synthesis of deoxyribonucleoside phosphoramidites is described. The amine hydrochloride produced as a by-product during the synthesis of nucleoside phosphorbisamidite is used as an internal activator in the synthesis of phosphoramidites. 相似文献
49.
Selwyn J. Hurwitz Li Ma Alessandra Eleuteri Janis Wright Josef Moravek Raymond F. Schinazi 《Nucleosides, nucleotides & nucleic acids》2013,32(3):691-702
Abstract The cellular pharmacology of the D- and L-enantiomers of β-5-o-carboranyl-2′-deoxyuridine (CDU), compounds designed for boron neutron capture therapy (BNCT), were studied using human CEM lymphoblast and U-251 glioblastoma cells, at a physiologically achievable concentration (1 μM). Accumulation of the enantiomers was rapid and indistinguishable, reaching cellular concentrations > 40-fold higher than extracellular levels, with ~5% persisting in cells after incubation in fresh medium for more than 2 hr. Uptake was not affected by nucleoside uptake inhibitors, but was inhibited by the purine base uptake inhibitor papaverine. 相似文献
50.
Laura Bonfili Massimiliano Cuccioloni Valentina Cecarini Matteo Mozzicafreddo Francesco Alessandro Palermo Paolo Cocci Mauro Angeletti Anna Maria Eleuteri 《Apoptosis : an international journal on programmed cell death》2013,18(10):1188-1200
Ghrelin is a metabolism-regulating hormone recently investigated for its role in cancer survival and progression. Controversially, ghrelin may act as either anti-apoptotic or pro-apoptotic factor in different cancer cells, suggesting that the effects are cell type dependent. Limited data are currently available on the effects exerted by ghrelin on intracellular proteolytic pathways in cancer. Both the lysosomal and the proteasomal systems are fundamental in cellular proliferation and apoptosis regulation. With the aim of exploring if the proteasome and autophagy may be possible targets of ghrelin in cancer, we exposed human colorectal adenocarcinoma cells to ghrelin. Preliminary in vitro fluorimetric assays evidenced for the first time a direct inhibition of 20S proteasomes by ghrelin, particularly evident for the trypsin-like activity. Moreover, 1 μM ghrelin induced apoptosis in colorectal adenocarcinoma cells by inhibiting the ubiquitin–proteasome system and by activating autophagy, with p53 having an “interactive” role. 相似文献