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Anania Pasquale Battaglini Denise Balestrino Alberto DAndrea Alessandro Prior Alessandro Ceraudo Marco Rossi Diego Criminelli Zona Gianluigi Fiaschi Pietro 《Neurosurgical review》2021,44(3):1243-1253
Neurosurgical Review - Posterior cranial fossa tumours frequently develop hydrocephalus as first presentation in up to 80% of paediatric patients and 21.4% of adults, although it resolves after... 相似文献
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A Novel Iterative Penalty Method to Enforce Boundary Conditions in Finite Volume POD-Galerkin Reduced Order Models for Fluid Dynamics Problems
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S. Kelbij Star Giovanni Stabile Francesco Belloni Gianluigi Rozza & Joris Degroote 《Communications In Computational Physics》2021,30(1):34-66
A Finite-Volume based POD-Galerkin reduced order model is developed for
fluid dynamics problems where the (time-dependent) boundary conditions are controlled using two different boundary control strategies: the lifting function method,
whose aim is to obtain homogeneous basis functions for the reduced basis space and
the penalty method where the boundary conditions are enforced in the reduced order
model using a penalty factor. The penalty method is improved by using an iterative
solver for the determination of the penalty factor rather than tuning the factor with a
sensitivity analysis or numerical experimentation.The boundary control methods are compared and tested for two cases: the classical lid driven cavity benchmark problem and a Y-junction flow case with two inlet
channels and one outlet channel. The results show that the boundaries of the reduced
order model can be controlled with the boundary control methods and the same order
of accuracy is achieved for the velocity and pressure fields. Finally, the reduced order
models are 270-308 times faster than the full order models for the lid driven cavity test
case and 13-24 times for the Y-junction test case. 相似文献
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Donato Gemmati Alessia Ongaro Gian L Scapoli Matteo Della Porta Silvia Tognazzo Maria L Serino Eros Di Bona Francesco Rodeghiero Giuseppe Gilli Roberto Reverberi Angelo Caruso Michela Pasello Agnese Pellati Monica De Mattei 《Cancer epidemiology, biomarkers & prevention》2004,13(5):787-794
Folate and methionine metabolism is involved in DNA synthesis and methylation processes. Polymorphisms in the genes of folate metabolism enzymes have been associated with some forms of cancer. In a case-control study, we evaluated whether four common polymorphisms in methylenetetrahydrofolate reductase (MTHFR C677T and A1298C), methionine synthase (MS A2756G), and methionine synthase reductase (MTRR A66G) genes may have a role in altering susceptibility to adult acute lymphoblastic leukemia (ALL) and non-Hodgkin's lymphoma (NHL). We analyzed DNA of 120 adult ALL, 200 NHL, and 257 healthy control subjects. Individual carrying the MTHFR 677TT genotype showed a 3.6-fold decreased ALL risk [odds ratio (OR) 0.28, 95% confidence interval (95% CI) 0.12-0.72] than wild-types. Similarly, MS 2756GG individuals showed a 5.0-fold decreased ALL risk (OR 0.20, 95% CI 0.02-1.45) than wild-types. In combined results, subjects with the MTHFR 677CT/TT and MS 2756AG/GG genotypes revealed a 3.6-fold ALL risk reduction (OR 0.28, 95% CI 0.14-0.58) and those with the MTHFR 677TT and MTRR 66AG genotypes revealed a 4.2-fold ALL risk reduction (OR 0.24, 95% CI 0.06-0.81). Finally, those with the MS 2756AG/GG and MTRR 66AG/GG genotypes revealed a 2.2-fold ALL risk reduction (OR 0.45, 95% CI 0.10-0.85). Single analysis for NHL did not show any significant difference for all the polymorphisms investigated, but in the low-grade NHL subgroup, we found a 2.0-fold risk reduction for the MTRR 66GG homozygous genotype (OR 0.50, 95% CI 0.25-0.99), which was higher (OR 0.37, 95% CI 0.14-0.85) when analyzed in combination with MS 2756AA genotype. These data are in accordance with the hypothesis that polymorphisms in the genes for folate and methionine metabolism might play a greater role in the occurrence of ALL than NHL by influencing DNA synthesis and/or DNA methylation. 相似文献
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Valeria Masciullo Tommaso Susini Alessandra Zamparelli Alessandro Bovicelli Corrado Minimo Daniela Massi Gianluigi Taddei Nicola Maggiano Pierandrea De Iaco Marcello Ceccaroni Luciano Bovicelli Gianni Amunni Salvatore Mancuso Giovanni Scambia Antonio Giordano 《Clinical cancer research》2003,9(14):5332-5338
PURPOSE: p27(Kip1) is a member of the Cip1/Kip1 family of cyclin-dependent kinase inhibitors and is a potential tumor suppressor gene. Low levels of p27 are associated with poor prognosis in a variety of gynecological tumors, including breast, ovarian, and cervical carcinomas. The role of p27 in endometrial cancer remains controversial. EXPERIMENTAL DESIGN: In the present study, p27 protein expression was investigated by immunohistochemistry in a series of 217 endometrial adenocarcinomas and, where present, in synchronous normal endometrium, simple and complex hyperplasia (with or without atypia), and cystic atrophy. The relationship between p27 expression and clinical outcome was also evaluated. RESULTS: Immunohistochemical analysis revealed a significant loss of p27 expression from normal (33%) through hyperplastic endometrium (50%) to endometrial adenocarcinomas (71%; P = 0.001). In addition to nuclear staining, cytoplasmic localization of p27 was noted in 193 (91%) of 217 specimens examined. When the clinical outcome of the patients was evaluated in relation to p27 status, we found no significant correlation between the presence of p27 staining and clinicopathological parameters or survival. CONCLUSIONS: These data indicate that p27 expression could progressively decrease from normal endometrium through hyperplastic endometrium to invasive endometrial carcinomas, suggesting that loss of this tumor suppressor may represent a novel and distinct molecular alteration involved in estrogen-related endometrial adenocarcinomas (type I). Despite the suggested role of the p27 protein in determining the prognosis of several human tumors, it was not found to be a predictor of clinical outcome in this large group of patients with endometrial cancer. 相似文献
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I. Barrai G. Formica R. Barale C. Scapoli R. Canella M. Beretta 《Annals of human biology》2013,40(1):7-18
The distribution of surnames in the emigrants from the population of the town of Ferrara in the period 1981–88 was studied by sex and by place of birth, namely Ferrara versus other places. Emigrants born in Ferrara were defined as first time emigrants and those who had previously immigrated to Ferrara were defined second time emigrants. It was found that random isonymy is smaller in second time emigrants. Sex ratio is not different in the two types of emigrants. As indicators of the abundance of surnames in a distribution, the common ecological indexes derived from entropy were used and compared between types of emigrants. It was found that redundancy, as isonymy, is larger in first time emigrants than in second time emigrants. It was observed that second time emigrants were consistently and significantly older than first time emigrants, and that a considerable fraction of them, (22·4%) returned to their place of birth. A sexual dimorphism in age at emigration was observed in second time emigrants, females emigrating at an older age than males. 相似文献
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Francesco Venturelli Giuliano Carrozzi Letizia Sampaolo Lara Bolognesi Sandro Baldissera Nicoletta Bertozzi Stefano Campostrini Benedetta Contoli Gianluigi Ferrante Maria Masocco Valentina Minardi Angelo D'Argenzio Pirous F Moghadam Luana Penna Alberto Perra Elisa Quarchioni Mauro Ramigni Massimo O Trinito Stefania Salmaso 《Lancet》2014
BackgroundInfluenza is an important public health problem, with potential severe consequences among people with chronic diseases. The aim of this study was to obtain reliable measures of seasonal influenza vaccine uptake in this population, otherwise not available in Italy.MethodsProgressi delle Aziende Sanitarie per la Salute in Italia (PASSI) is a nationwide surveillance system of health-related behaviours and acceptance of preventive interventions (including influenza immunisation) offered by the Italian National Health Service. Data are collected with telephone interviews at local health unit level for supporting local activities. The survey sample is randomly selected from local health unit lists of adult residents. The trend of annual vaccine coverage since 2008 was estimated for people aged 18–64 years who reported having at least one chronic disease. To obtain a sufficient sample size in subgroups, we analysed the characteristics of vaccinated people in the 2010–13 cumulative dataset. Univariate, multivariate, and logistic regression analyses were undertaken.FindingsIn 2008–13, 13 659 individuals with at least one chronic disease were interviewed. Vaccination coverage fell significantly from 29·7% (95% CI 27·2–32·4) in 2007–08 to 19·9% (18·0–22·1) in 2012–13. During 2010–13, the overall proportion of vaccinated people with a chronic disease was 25·6% (24·5–26·7). Vaccine coverage of people with diabetes (34·3%, 31·7–36·9) or cardiovascular diseases (31·8%, 29·6–34·2) was greater than that of people affected by renal failure, respiratory diseases, tumours, or chronic liver diseases (26·5% [22·5–30·7], 24·9% [23·2–26·7], 22·2% [20·0–24·6], and 20·6% [17·5–24·6], respectively). Vaccination coverage increased with age (from 13·1% [11·0–15·5] in the 18–34 year age group to 33·4% [31·9–35·1] in people aged 50–64 years); it was higher among people with a low educational level than among those with a high educational level, higher in those having economic difficulties than in those with no economic difficulties, and higher among Italian citizens than among non-citizens.InterpretationIn the past few years, prevalence of influenza vaccination in Italian adults with at least one chronic disease was well below the Ministry of Health's goal (75% minimum) and showed a downward trend. A major reason of this evolution is probably the changing public perception of the benefits and risks of vaccines. PASSI is a source of useful data not otherwise available for public health intervention.FundingItalian Ministry of Health. 相似文献