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51.
52.
Caligiuri A Bertolani C Guerra CT Aleffi S Galastri S Trappoliere M Vizzutti F Gelmini S Laffi G Pinzani M Marra F 《Hepatology (Baltimore, Md.)》2008,47(2):668-676
Adiponectin limits the development of liver fibrosis and activates adenosine monophosphate-activated protein kinase (AMPK). AMPK is a sensor of the cellular energy status, but its possible modulation of the fibrogenic properties of hepatic stellate cells (HSCs) has not been established. In this study, we investigated the role of AMPK activation in the biology of activated human HSCs. A time-dependent activation of AMPK was observed in response to a number of stimuli, including globular adiponectin, 5-aminoimidazole-4-carboxamide-1-beta-4-ribofuranoside (AICAR), or metformin. All these compounds significantly inhibited platelet-derived growth factor (PDGF)-stimulated proliferation and migration of human HSCs and reduced the secretion of monocyte chemoattractant protein-1. In addition, AICAR limited the secretion of type I procollagen. Knockdown of AMPK by gene silencing increased the mitogenic effects of PDGF, confirming the negative modulation exerted by this pathway on HSCs. AMPK activation did not reduce PDGF-dependent activation of extracellular signal-regulated kinase (ERK) or Akt at early time points, whereas a marked inhibition was observed 24 hours after addition of PDGF, reflecting a block in cell cycle progression. In contrast, AICAR blocked short-term phosphorylation of ribosomal S6 kinase (p70(S6K)) and 4E binding protein-1 (4EBP1), 2 downstream effectors of the mammalian target of rapamycin (mTOR) pathway, by PDGF. The ability of interleukin-a (IL-1) to activate nuclear factor kappa B (NF-kappaB) was also reduced by AICAR. CONCLUSION: Activation of AMPK negatively modulates the activated phenotype of HSCs. 相似文献
53.
Nilsson L Faldella G Jacquet JM Storsaeter J Silfverdal SA Ekholm L 《Scandinavian journal of infectious diseases》2005,37(3):221-229
Healthy 4-6 y old children from Italy and Sweden immunized with DTPa and inactivated or oral polio vaccines at 3, 5 and 11-12 months of age, received 1 dose of combined DTPa-IPV (n = 211) or DTPa + IPV as separate doses (n = 205) in a randomized trial. The pre-booster seroprotection rates were similar in each group and were above 60% against all antigens except diphtheria (31.3% and 37.0%) and PT (21.5% and 25.9%) in the DTPa-IPV and DTPa + IPV groups, respectively. At least 99.5% of subjects had seroprotective antibody levels against diphtheria, tetanus and polioviruses and > or = 96% showed a vaccine response to each pertussis antigen after vaccination. Post-booster antibody levels increased at least 51-fold for anti-diphtheria and anti-tetanus, at least 18-fold for anti-pertussis antibodies and at least 32-fold for antibodies against all 3 poliovirus types, compared to prior levels. DTPa-IPV was comparable to DTPa + IPV in terms of seroprotection rates and mean antibody levels against each vaccine antigen. Similar reactogenicity profiles were observed between groups including swelling > 50 mm [13% (9.1, 18.7) vs 17% (12.4, 23.4)] or involving an adjacent joint [0% (-,-) vs 1.5% (0.3, 4.3)] and were consistent with previous reports. The combined DTPa-IPV vaccine could be used to add DTP valences to the IPV vaccine currently given to children in Scandinavia and Italy at 4-6 y of age and reinforce protection against 4 diseases. 相似文献
54.
Morphological evidence of Campylobacter pylori pathogenicity in chronic gastritis and peptic ulcer 总被引:2,自引:0,他引:2
R Fiocca L Villani C De Giacomo M Perego E Trespi E Solcia 《Acta gastro-enterologica Belgica》1989,52(3-4):324-335
Campylobacter pylori (CP) were found in 84% of 384 patients with chronic gastritis and in none of 49 subjects without inflammation. CP were present in similar percentages among patients with active (90%) or healed peptic ulcer (84%), as well as in non-ulcerous dyspepsia complicated by gastritis (91%). Cytoplasmic vacuolization and swelling of foveolar-superficial cells with adhering bacteria, micropapillae and microerosions were commonly found in CP-infected mucosa. In 100 cases with gastritis both intraepithelial granulocytes and epithelial lesions were prominent features of heavily CP-infected antral mucosa. The occurrence of some cases with abundant, adhering CP but lacking epithelial lesions is in keeping with the different ability of various CP-strains to produce cytotoxins. In 16 of 19 children with type B chronic gastritis antibacterial therapy eradicated CP. This was followed by resolution or striking improvement of gastritis and disappearance of epithelial lesions. These data provide further morphological evidence of direct cytotoxic activity of CP toward gastric mucosal cells. 相似文献
55.
Silvia Varani Rita Ostan Luca Franchini Giacomo Ercolani Raffaella Pannuti Guido Biasco Eduardo Bruera 《Journal of pain and symptom management》2021,61(2):e4-e12
ContextProviding palliative care (PC) at home for patients with advanced cancer has become essential during the COVID-19 emergency. Nevertheless, the home PC professionals (PCPs) faced a challenging situation because of increased number of discharged patients, reduced availability of health-care facilities, and physical/relational barriers between them and patients.ObjectivesThis study aimed to investigate the impact of COVID-19 pandemic on burnout and psychological morbidity among home PCPs in Italy.MethodsOne hundred and ninety-eight PC physicians and nurses working in home assistance in Italy were invited to participate. The results obtained by the investigation conducted during the COVID-19 emergency (COVID2020) were compared with data collected in 2016 in the same setting (BURNOUT2016). The questionnaires (socio-demographics, Maslach Burnout Inventory and General Health Questionnaire-12) were the same for both the surveys. The PCPs participating in COVID2020 survey (n = 145) were mostly the same (70%) who participated in the BURNOUT2016 study (n = 179).ResultsOne hundred and forty-five PCPs participated in the study (response rate 73.2%). During the COVID-19 emergency, home PCPs presented a lower burnout frequency (P < .001) and higher level of personal accomplishment than in 2016 (P = .047). Conversely, the risk for psychological morbidity was significantly higher during the pandemic (P < .001).ConclusionsIn the age of COVID-19, the awareness of being at the forefront of containing the pandemic along with the sense of responsibility toward their high-risk patients may arouse PCPs' psychological distress, but, on the other hand, this condition may improve their sense of professional satisfaction and personal accomplishment. 相似文献
56.
Carmen Barba Massimo Cossu Renzo Guerrini Giancarlo Di Gennaro Flavio Villani Luca De Palma Laura Grisotto Alessandro Consales Domenica Battaglia Nelia Zamponi Piergiorgio dOrio Martina Revay Michele Rizzi Sara Casciato Vincenzo Esposito Pier Paolo Quarato Roberta Di Giacomo Giuseppe Didato Chiara Pastori Giusy Carfi Pavia Simona Pellacani Giulia Matta Mattia Pacetti Gianpiero Tamburrini Elisabetta Cesaroni Gabriella Colicchio Giampaolo Vatti Sofia Asioli Massimo Caulo Carlo Efisio Marras Laura Tassi 《Epilepsia》2021,62(1):128-142
57.
Giacomo Ramponi Marco Folci Maria De Santis Jan G.M.C. Damoiseaux Carlo Selmi Enrico Brunetta 《Autoimmunity reviews》2021,20(3):102759
Anti-neutrophil cytoplasmic antibodies (ANCA) are a group of autoantibodies, predominantly IgG, involved in the pathogenesis of several autoimmune disorders, detected either through indirect immunofluorescence or enzyme-linked immunosorbent assay. By means of indirect immunofluorescence, the main patterns are C-ANCA (cytoplasmic) and P-ANCA (perinuclear), while proteinase 3 (PR3) and myeloperoxidase (MPO) represent the main autoantigens in granulomatosis with polyangiitis and microscopic polyangiitis, both belonging to the family of ANCA-associated vasculitis (AAV). While several experiments established the pathogenicity of MPO-ANCA, evidence remains elusive for PR3-ANCA and an additional target antigen, i.e. LAMP2, has been postulated with specific clinical relevance. The presence of a subset of AAV without ANCA may be explained by the presence of further target antigens or the presence of molecules in blood which make ANCA undetectable. A rise in ANCA titers is not necessarily predictive of a flare of disease in AAV if not accompanied by clinical manifestations. ANCA may develop through variable mechanisms, such as autoantigen complementarity, apoptosis impairment, neutrophil extracellular traps dysfunction and molecular mimicry. We will provide herein a comprehensive review of the available evidence on the biological mechanisms, pathogenetic role, and clinical implications of ANCA testing and disease management. Further, we will address the remaining open challenges in the field, including the role of ANCA in inflammatory bowel disease and in cocaine-induced vasculitis. 相似文献
58.
Daniela Di Giacomo Pascaline Gaildrat Anna Abuli Julie Abdat Thierry Frébourg Mario Tosi Alexandra Martins 《Human mutation》2013,34(11):1547-1557
Exonic variants can alter pre‐mRNA splicing either by changing splice sites or by modifying splicing regulatory elements. Often these effects are difficult to predict and are only detected by performing RNA analyses. Here, we analyzed, in a minigene assay, 26 variants identified in the exon 7 of BRCA2, a cancer predisposition gene. Our results revealed eight new exon skipping mutations in this exon: one directly altering the 5′ splice site and seven affecting potential regulatory elements. This brings the number of splicing regulatory mutations detected in BRCA2 exon 7 to a total of 11, a remarkably high number considering the total number of variants reported in this exon (n = 36), all tested in our minigene assay. We then exploited this large set of splicing data to test the predictive value of splicing regulator hexamers’ scores recently established by Ke et al. ( 2011 ). Comparisons of hexamer‐based predictions with our experimental data revealed high sensitivity in detecting variants that increased exon skipping, an important feature for prescreening variants before RNA analysis. In conclusion, hexamer scores represent a promising tool for predicting the biological consequences of exonic variants and may have important applications for the interpretation of variants detected by high‐throughput sequencing. 相似文献
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