185 research outputs found
The Distrimobs approach for parallelization of pedestrian mobility computations
Simulating pedestrian mobility is a typical centralized problem where each agent must interact with a plurality of other agents in order to make decisions about its local path planning. Distrimobs is a parallel- and distributed-agent–based pedestrian mobility simulator able to represent thousands of agents while keeping a good scalability. The aim of the Distrimobs simulator is to simulate the whole
Carnival of Venice. In this work we present the Distrimobs approach for parallelization of the computations and some experimental results of performance intensive scenarios. These results highlight the scalability and the computational complexity of the simulator
FRAT-up, a Web-based fall-risk assessment tool for elderly people living in the community.
Background: About 30% of people over 65 are subject to at least one unintentional fall a year. Fall prevention protocols and
interventions can decrease the number of falls. To be effective, a prevention strategy requires a prior step to evaluate the fall risk
of the subjects. Despite extensive research, existing assessment tools for fall risk have been insufficient for predicting falls.
Objective: The goal of this study is to present a novel web-based fall-risk assessment tool (FRAT-up) and to evaluate its accuracy
in predicting falls, within a context of community-dwelling persons aged 65 and up.
Methods: FRAT-up is based on the assumption that a subject\u2019s fall risk is given by the contribution of their exposure to each
of the known fall-risk factors. Many scientific studies have investigated the relationship between falls and risk factors. The
majority of these studies adopted statistical approaches, usually providing quantitative information such as odds ratios. FRAT-up
exploits these numerical results to compute how each single factor contributes to the overall fall risk. FRAT-up is based on a
formal ontology that enlists a number of known risk factors, together with quantitative findings in terms of odds ratios. From
such information, an automatic algorithm generates a rule-based probabilistic logic program, that is, a set of rules for each risk
factor. The rule-based program takes the health profile of the subject (in terms of exposure to the risk factors) and computes the
fall risk. A Web-based interface allows users to input health profiles and to visualize the risk assessment for the given subject.
FRAT-up has been evaluated on the InCHIANTI Study dataset, a representative population-based study of older persons living
in the Chianti area (Tuscany, Italy). We compared reported falls with predicted ones and computed performance indicators.
Results: The obtained area under curve of the receiver operating characteristic was 0.642 (95% CI 0.614-0.669), while the Brier
score was 0.174. The Hosmer-Lemeshow test indicated statistical significance of miscalibration.
Conclusions: FRAT-up is a web-based tool for evaluating the fall risk of people aged 65 or up living in the community. Validation
results of fall risks computed by FRAT-up show that its performance is comparable to externally validated state-of-the-art tools.
A prototype is freely available through a web-based interface.
Trial Registration: ClinicalTrials.gov NCT01331512 (The InChianti Follow-Up Study);
http://clinicaltrials.gov/show/NCT01331512 (Archived by WebCite at http://www.webcitation.org/6UDrrRuaR)
Development of a clinical prediction model for the onset of functional decline in people aged 65-75 years: Pooled analysis of four European cohort studies
Background: Identifying those people at increased risk of early functional decline in activities of daily living (ADL) is essential for initiating preventive interventions. The aim of this study is to develop and validate a clinical prediction model for onset of functional decline in ADL in three years of follow-up in older people of 65-75 years old. Methods: Four population-based cohort studies were pooled for the analysis: ActiFE-ULM (Germany), ELSA (United Kingdom), InCHIANTI (Italy), LASA (Netherlands). Included participants were 65-75 years old at baseline and reported no limitations in functional ability in ADL at baseline. Functional decline was assessed with two items on basic ADL and three items on instrumental ADL. Participants who reported at least some limitations at three-year follow-up on any of the five items were classified as experiencing functional decline. Multiple logistic regression analysis was used to develop a prediction model, with subsequent bootstrapping for optimism-correction. We applied internal-external cross-validation by alternating the data from the four cohort studies to assess the discrimination and calibration across the cohorts. Results: Two thousand five hundred sixty community-dwelling people were included in the analyses (mean age 69.7 ± 3.0 years old, 47.4% female) of whom 572 (22.3%) reported functional decline at three-year follow-up. The final prediction model included 10 out of 22 predictors: age, handgrip strength, gait speed, five-repeated chair stands time (non-linear association), body mass index, cardiovascular disease, diabetes, chronic obstructive pulmonary disease, arthritis, and depressive symptoms. The optimism-corrected model showed good discrimination with a C statistic of 0.72. The calibration intercept was 0.06 and the calibration slope was 1.05. Internal-external cross-validation showed consistent performance of the model across the four cohorts. Conclusions: Based on pooled cohort data analyses we were able to show that the onset of functional decline in ADL in three years in older people aged 65-75 years can be predicted by specific physical performance measures, age, body mass index, presence of depressive symptoms, and chronic conditions. The prediction model showed good discrimination and calibration, which remained stable across the four cohorts, supporting external validity of our findings
The p53 Codon 72 Pro/Pro Genotype Identifies Poor-Prognosis Neuroblastoma Patients: Correlation with Reduced Apoptosis and Enhanced Senescence by the p53-72P Isoform.
The p53 gene is rarely mutated in neuroblastoma, but codon 72 polymorphism that modulates its proapoptotic activity might influence cancer risk and clinical outcome. We investigated whether this polymorphism affects neuroblastoma risk and disease outcome and assessed the biologic effects of the p53-72R and p53-72P isoforms in p53-null cells. Comparison of 288 healthy subjects and 286 neuroblastoma patients revealed that the p53-72 polymorphism had no significant impact on the risk of developing neuroblastoma; however, patients with the Pro/Pro genotype had a shorter survival than those with the Arg/Arg or the Arg/Pro genotypes even in the stage 3 and 4 subgroup without MYCN amplification. By Cox regression analysis, the p53 Pro/Pro genotype seems to be an independent marker of poor prognosis (hazard ratio = 2.74; 95% confidence interval = 1.14\u20136.55, P = .014) together with clinical stage, MYCN status, and age at diagnosis. In vitro, p53-72P was less effective than p53-72R in inducing apoptosis and inhibiting survival of p53-null LAN-1 cells treated with etoposide, topotecan, or ionizing radiation but not taxol. By contrast, p53-72P was more effective in promoting p21-dependent accelerated senescence, alone or in the presence of etoposide. Thus, the p53-72 Pro/Pro genotype might be a marker of poor outcome independent of MYCN amplification, possibly improving risk stratification. Moreover, the lower apoptosis and the enhanced accelerated senescence by the p53-72P isoform in response to DNA damage suggest that patients with neuroblastoma with the p53-72 Pro/Pro genotype may benefit from therapeutic protocols that do not rely only on cytotoxic drugs that function, in part, through p53 activation
The largest multicentre data collection on prepectoral breast reconstruction: The iBAG study
Background and Objectives: In the last years, prepectoral breast reconstruction has increased its popularity, becoming a standard reconstructive technique by preserving pectoralis major anatomy and functionality. Nevertheless, the lack of solid and extensive data negatively impacts on surgeons\u2019 correct information about postoperative complication rates and proper patient selection. This study aims to collect the largest evidence on this procedure. Methods: A multicentre retrospective audit, promoted by the Barcelona Hospital, collected the experience of 30 centers on prepectoral breast reconstruction with Braxon ADM. The study had the scientific support of INPECS and IIB societies which provided the online database Clinapsis. Results: A total of 1450 procedures were retrospectively collected in a 6-year period. Mean age 52.4 years, BMI 23.9, follow-up 22.7 months. Reconstruction was carried out after a tumor in 77.1% of the cases, 20.1% had prophylactic surgery, 2.8% had revisions. Diabetes, smoke, and immunosuppression had an influence on complications occurrence, as well as implant weight. Capsular contracture was associated with postoperative radiotherapy, but the overall rate was low (2.1%). Complications led to implant loss in 6.5% of the cases. Conclusions: The international Braxon Audit Group multicentre data collection represents a milestone in the field of breast reconstruction, extensively improving the knowledge of this procedure
Abdominal visceral hernia through a chest wall defect secondary to open-window thoracostomy
Chirurgia per carcinoma mammario con modalità day- o one-day surgery: un’esperienza di 12 anni
adjuvant treatment with tamoxifene and B- Interferon in premonopausal and postmenopausal women with breast cancer
- …